The United States continues to confront an opioid crisis that also affects older adults. According to the Substance Abuse and Mental Health Services Administration from 1999 to 2010, there has been a 4-fold increase in opioid overdose deaths.¹ Between 2010 and 2015, the rate of opioid-related inpatient stays and emergency department (ED) visits for people aged ≥ 65 years increased by 34% and 74%, respectively, and opioid-related overdose deaths continue to increase among older patients.^1,2

Background

Chronic pain is estimated to affect 50 million US adults.³ Individuals receiving long-term opioid therapy may not have experienced relief with other medications or cannot take them for medical safety reasons. Losing access to opioid prescriptions can contribute to misuse of illicit opioids. Implementing best practices for prescription opioid management in older adults is challenging. Older adults have a high prevalence of chronic pain, which is linked to disability and loss of function, reduced mobility, falls, depression, anxiety, sleep disorders, social isolation, and suicide or suicidal ideation.⁴ Until recently, chronic pain in older adults was often treated primarily with long-term opioid prescriptions, despite little evidence for the effectiveness of that treatment for chronic conditions. The prevalence of long-term opioid use in adults has increased from 1.8% (1999-2000) to 5.4% (2013-2014), and 25% of adult long-term opioid users are aged ≥ 65 years.⁵

Older adults are especially vulnerable to developing adverse events (AEs) from opioid use, including constipation, confusion, nausea, falls, and overdose. These factors make safe prescribing more challenging even when opioids are an appropriate therapeutic choice. Older adults often have multiple chronic conditions and take multiple medications that increase risk of AEs due to drug-disease and drug-drug interactions. Finding appropriate alternatives for pain management can be challenging in the presence of dementia if other pharmacologic options are contraindicated or mobility issues limit access to other therapeutic options.

Pain treatment plans should be based on realistic functional goals using a shared decision-making approach accounting for patient and provider expectations. All reasonable nondrug and nonopioid treatments should be considered before opioids are initiated. A comprehensive, person-centered, approach to pain management in older adults that includes opioids, other medications, and complementary and integrative care could improve both pain control and function,and reduce the harms of unnecessary opioid exposure.⁶ A validated risk review should be performed and documented on all patients starting opioids except patients enrolled in hospice care.

In 2018, the US Department of Veterans Affairs (VA) required all facilities to complete case reviews for veterans identified in the Stratification Tool for Opioid Risk Mitigation (STORM) dashboard as being at particularly high risk for AEs among patients prescribed opioids.⁷ We present our experience with a 1-year management of 48 high-risk older patients receiving chronic prescription opioid therapy. These patients obtained all their care at the VA with complete record documentation.

Methods

The Tennessee Valley Healthcare System (TVHS) is an integrated VA health care system with > 100,000 veteran patients in middle Tennessee with 2 medical centers 40 miles apart, and 12 community-based outpatient clinics. In 2011, TVHS developed a geriatric patient-centered medical home model for geriatric primary care—the geriatric patient aligned care team (GeriPACT).⁸ GeriPACT consists of a GeriPACT primary care provider (geriatrician or geriatric nurse practitioner with a panel of about 800 outpatients), social worker, clinical pharmacist, registered nurse care manager, licensed vocational nurse, and clerical staff. GeriPACT is a special population PACT within primary care for complex geriatric and other high-risk vulnerable veterans providing integrated, interdisciplinary assessment and longitudinal management, and coordination of both VA and non-VA-funded (eg, Medicare and Medicaid) services for patients and caregivers. GeriPACT at the Nashville TVHS campus has an enrollment of 745 patients of whom 48 receive chronic prescription opioid therapy. The practice is supported by the VA Computerized Patients Record System (CPRS), including the electronic patient portal, My healtheVet, with telemedicine capabilities. Data were collected by chart review with operations data extracted from the Veterans Health Information System and Technology Architecture.

Best practices for prescription opioids for chronic pain follow the US Department of Health and Human Services Interagency Task Force pain management recommendations.⁴ These include: (1) Effective pain evaluation and management, including diagnostic evaluation and indicated referrals; (2) appropriately prescribed opioids when indicated; and (3) active management of opioid users to prevent AEs and misuse. Strategies used in GeriPACT were adopted from the pain management task force and designed to address needs and challenges associated with responsible chronic opioid prescribing (Table 1).

Results

Chronic opioid patients comprised 6.4% of the GeriPACT population. These patients had many comorbidities, including diabetes mellitus (35%), pulmonary disease (25%), congestive heart failure (18.8%), and dementia (8%). There were 54% with estimated glomerular filtration rates (eGFR) < 60 mL/min, indicating at least stage 3 chronic kidney disease (Table 2). Patients had an average RIOSORD Score of 21 and a 14% risk of opioid induced respiratory depression, and 20% received mental health services.

The mean CAN score was 83.1, suggesting a 1-year risk of 20% for a major AE and 5% mortality risk. Many patients with chronic opioid use were transferred to GeriPACT from primary care due to presence of complex medical issues in addition to need for chronic pain management. In this population, 8% were coprescribed benzodiazepines and opioids. Consults were obtained from interventional pain for 37.5% of patients and palliative care for 27% of patients, the majority for goals of care related to chronic illness and advance directive discussions, and in 1 patient for pain and symptom management. The majority of patients (81%) had advance care planning documents or discussions documented in the electronic health record, and 87.5% of patients received home and community-based support in addition to GeriPACT care.

Medication Reduction

Pharmacists routinely counseled patients regarding the appropriate timing of refills and made monthly calls to request refills of controlled drugs. Three patients agreed to opioid dose reduction due to improved clinical status. Two patients had 25% and 30% dose reductions, respectively, and 1 patient was able to be discontinue opioids. This was achieved through reduction of therapy and or substitution of alternative nonopioid pain medications. One patient was initiated on a slow benzodiazepine taper schedule after decades of benzodiazepine use in addition to engagement with a whole health coach and primary care mental health integration provider. Another patient was disenrolled from the clinic because of repeated nonadherence and positive UDSs for polysubstance use disorder.

Accidental Overdoses

There were 2 patients with accidental overdoses who survived, both on high morphine equivalent daily doses (MEDDs). One patient was admitted to the intensive care unit for increasing confusion after taking more than the prescribed opioids (120 mg MEDD) due to uncontrolled pain for 2 months following surgery. The second patient was taking 66 mg MEDD with multiple risk factors for respiratory depression (severe chronic obstructive pulmonary disease requiring oxygen, obstructive sleep apnea, and concomitant benzodiazepine use) who repeatedly refused tapering of opioids and benzodiazepines. He was found unresponsive in respiratory depression by home health staff. Both patients had naloxone kits in their home that were not administered.

Urine Drug Screening

There was an occasional negative opioid UDS attributed to patients on a low-dose opioid administered more than 24 hours before. Five patients (10.4%) had positive UDSs. Two patients were positive for cocaine, and because of chronic persistent pain and complex medical problems cared for in the clinic, counseled and continued on therapy with no repeat infractions. Two patients were positive for cannabinoids attributed to CBD oil products, which are legal in Tennessee. One patient had repeated positive UDSs for polysubstance abuse and was terminated from the clinic, preferring to use cannabinoids and other substances illegally. Meperidine, fentanyl, tramadol, and other synthetic opioids are not detected on a routine UDS.

Discussion

Primary care is critical in optimizing the prescribing and use of opioids in older adults. The patient-centered medical home can give health care providers the tools and support to provide evidence—based pain management for their older adult patients and to facilitate prescription and monitoring of appropriate opioid use to minimizing AEs and OUD risk. This includes a reliable health information technology monitoring system as part of a collaborative, person-centered care practice capable of managing frail older patients with multiple chronic conditions as well as social risk factors. GeriPACT was able to implement guideline—based evaluation and treatment of chronic pain patients through optimal management of opioids, risk reduction, and monitoring and management of AEs, misuse, and dose tapering using shared decision-making strategies when appropriate.

Complex older patients on chronic opioid treatment can do well and are best managed by an interdisciplinary team. Our panel had a high prevalence of chronic opioid patients and a high expected mortality based on the severity of comorbidities. Patients had frequent access to care with utilization of many support services. Patients received care for many chronic illnesses at the same time they received opioid therapy and generally were satisfied and adherent to their treatment plan. Published reports of the prevalence of coprescribing of benzodiazepines and opioids of 1.1 to 2.7% in the general population, may be lower than our veteran population.¹⁴ Despite the fact that nearly 20% of the population had a history of opioid misuse, only 1 patient was terminated from the clinic because of repeated episodes of polysubstance use disorder.

GeriPACT has the capability to be responsive to the changing needs of older chronic pain patients as a learning health system using continuous process improvement with frequent team meetings and interdisciplinary care.¹⁵ Our experience with chronic pain management demonstrates the feasibility and quality of guideline-based management and enhances our understanding of the intersection of care, chronic pain management, and opioid use disorder in older adults.

Limitations

Our experience with this population of older veterans may not be applicable to other geriatric populations. While all patients received their primary care at VA and patients were seen regularly, our data may not account for possible use of some community services, including hospitalization and long-term care.

Conclusions

Guideline-based patient-centered medical home management of patients with chronic pain treated with opioids can be an effective model to maintain and improve measures of health and well-being in older patients. Primary care management is critical in optimizing the prescribing and use of opioids in older adults. These complex older patients are best managed by an interdisciplinary team.

Acknowledgments

This work was supported in part by the Geriatric Workforce Enhancement Program, HRSA Grant: 1-U1Q-HP 033085-01-00.

The United States continues to confront an opioid crisis that also affects older adults. According to the Substance Abuse and Mental Health Services Administration from 1999 to 2010, there has been a 4-fold increase in opioid overdose deaths.¹ Between 2010 and 2015, the rate of opioid-related inpatient stays and emergency department (ED) visits for people aged ≥ 65 years increased by 34% and 74%, respectively, and opioid-related overdose deaths continue to increase among older patients.^1,2

Background

Chronic pain is estimated to affect 50 million US adults.³ Individuals receiving long-term opioid therapy may not have experienced relief with other medications or cannot take them for medical safety reasons. Losing access to opioid prescriptions can contribute to misuse of illicit opioids. Implementing best practices for prescription opioid management in older adults is challenging. Older adults have a high prevalence of chronic pain, which is linked to disability and loss of function, reduced mobility, falls, depression, anxiety, sleep disorders, social isolation, and suicide or suicidal ideation.⁴ Until recently, chronic pain in older adults was often treated primarily with long-term opioid prescriptions, despite little evidence for the effectiveness of that treatment for chronic conditions. The prevalence of long-term opioid use in adults has increased from 1.8% (1999-2000) to 5.4% (2013-2014), and 25% of adult long-term opioid users are aged ≥ 65 years.⁵

Older adults are especially vulnerable to developing adverse events (AEs) from opioid use, including constipation, confusion, nausea, falls, and overdose. These factors make safe prescribing more challenging even when opioids are an appropriate therapeutic choice. Older adults often have multiple chronic conditions and take multiple medications that increase risk of AEs due to drug-disease and drug-drug interactions. Finding appropriate alternatives for pain management can be challenging in the presence of dementia if other pharmacologic options are contraindicated or mobility issues limit access to other therapeutic options.

Pain treatment plans should be based on realistic functional goals using a shared decision-making approach accounting for patient and provider expectations. All reasonable nondrug and nonopioid treatments should be considered before opioids are initiated. A comprehensive, person-centered, approach to pain management in older adults that includes opioids, other medications, and complementary and integrative care could improve both pain control and function,and reduce the harms of unnecessary opioid exposure.⁶ A validated risk review should be performed and documented on all patients starting opioids except patients enrolled in hospice care.

In 2018, the US Department of Veterans Affairs (VA) required all facilities to complete case reviews for veterans identified in the Stratification Tool for Opioid Risk Mitigation (STORM) dashboard as being at particularly high risk for AEs among patients prescribed opioids.⁷ We present our experience with a 1-year management of 48 high-risk older patients receiving chronic prescription opioid therapy. These patients obtained all their care at the VA with complete record documentation.

Methods

The Tennessee Valley Healthcare System (TVHS) is an integrated VA health care system with > 100,000 veteran patients in middle Tennessee with 2 medical centers 40 miles apart, and 12 community-based outpatient clinics. In 2011, TVHS developed a geriatric patient-centered medical home model for geriatric primary care—the geriatric patient aligned care team (GeriPACT).⁸ GeriPACT consists of a GeriPACT primary care provider (geriatrician or geriatric nurse practitioner with a panel of about 800 outpatients), social worker, clinical pharmacist, registered nurse care manager, licensed vocational nurse, and clerical staff. GeriPACT is a special population PACT within primary care for complex geriatric and other high-risk vulnerable veterans providing integrated, interdisciplinary assessment and longitudinal management, and coordination of both VA and non-VA-funded (eg, Medicare and Medicaid) services for patients and caregivers. GeriPACT at the Nashville TVHS campus has an enrollment of 745 patients of whom 48 receive chronic prescription opioid therapy. The practice is supported by the VA Computerized Patients Record System (CPRS), including the electronic patient portal, My healtheVet, with telemedicine capabilities. Data were collected by chart review with operations data extracted from the Veterans Health Information System and Technology Architecture.

Best practices for prescription opioids for chronic pain follow the US Department of Health and Human Services Interagency Task Force pain management recommendations.⁴ These include: (1) Effective pain evaluation and management, including diagnostic evaluation and indicated referrals; (2) appropriately prescribed opioids when indicated; and (3) active management of opioid users to prevent AEs and misuse. Strategies used in GeriPACT were adopted from the pain management task force and designed to address needs and challenges associated with responsible chronic opioid prescribing (Table 1).

Results

Chronic opioid patients comprised 6.4% of the GeriPACT population. These patients had many comorbidities, including diabetes mellitus (35%), pulmonary disease (25%), congestive heart failure (18.8%), and dementia (8%). There were 54% with estimated glomerular filtration rates (eGFR) < 60 mL/min, indicating at least stage 3 chronic kidney disease (Table 2). Patients had an average RIOSORD Score of 21 and a 14% risk of opioid induced respiratory depression, and 20% received mental health services.

The mean CAN score was 83.1, suggesting a 1-year risk of 20% for a major AE and 5% mortality risk. Many patients with chronic opioid use were transferred to GeriPACT from primary care due to presence of complex medical issues in addition to need for chronic pain management. In this population, 8% were coprescribed benzodiazepines and opioids. Consults were obtained from interventional pain for 37.5% of patients and palliative care for 27% of patients, the majority for goals of care related to chronic illness and advance directive discussions, and in 1 patient for pain and symptom management. The majority of patients (81%) had advance care planning documents or discussions documented in the electronic health record, and 87.5% of patients received home and community-based support in addition to GeriPACT care.

Medication Reduction

Pharmacists routinely counseled patients regarding the appropriate timing of refills and made monthly calls to request refills of controlled drugs. Three patients agreed to opioid dose reduction due to improved clinical status. Two patients had 25% and 30% dose reductions, respectively, and 1 patient was able to be discontinue opioids. This was achieved through reduction of therapy and or substitution of alternative nonopioid pain medications. One patient was initiated on a slow benzodiazepine taper schedule after decades of benzodiazepine use in addition to engagement with a whole health coach and primary care mental health integration provider. Another patient was disenrolled from the clinic because of repeated nonadherence and positive UDSs for polysubstance use disorder.

Accidental Overdoses

There were 2 patients with accidental overdoses who survived, both on high morphine equivalent daily doses (MEDDs). One patient was admitted to the intensive care unit for increasing confusion after taking more than the prescribed opioids (120 mg MEDD) due to uncontrolled pain for 2 months following surgery. The second patient was taking 66 mg MEDD with multiple risk factors for respiratory depression (severe chronic obstructive pulmonary disease requiring oxygen, obstructive sleep apnea, and concomitant benzodiazepine use) who repeatedly refused tapering of opioids and benzodiazepines. He was found unresponsive in respiratory depression by home health staff. Both patients had naloxone kits in their home that were not administered.

Urine Drug Screening

There was an occasional negative opioid UDS attributed to patients on a low-dose opioid administered more than 24 hours before. Five patients (10.4%) had positive UDSs. Two patients were positive for cocaine, and because of chronic persistent pain and complex medical problems cared for in the clinic, counseled and continued on therapy with no repeat infractions. Two patients were positive for cannabinoids attributed to CBD oil products, which are legal in Tennessee. One patient had repeated positive UDSs for polysubstance abuse and was terminated from the clinic, preferring to use cannabinoids and other substances illegally. Meperidine, fentanyl, tramadol, and other synthetic opioids are not detected on a routine UDS.

Discussion

Primary care is critical in optimizing the prescribing and use of opioids in older adults. The patient-centered medical home can give health care providers the tools and support to provide evidence—based pain management for their older adult patients and to facilitate prescription and monitoring of appropriate opioid use to minimizing AEs and OUD risk. This includes a reliable health information technology monitoring system as part of a collaborative, person-centered care practice capable of managing frail older patients with multiple chronic conditions as well as social risk factors. GeriPACT was able to implement guideline—based evaluation and treatment of chronic pain patients through optimal management of opioids, risk reduction, and monitoring and management of AEs, misuse, and dose tapering using shared decision-making strategies when appropriate.

Complex older patients on chronic opioid treatment can do well and are best managed by an interdisciplinary team. Our panel had a high prevalence of chronic opioid patients and a high expected mortality based on the severity of comorbidities. Patients had frequent access to care with utilization of many support services. Patients received care for many chronic illnesses at the same time they received opioid therapy and generally were satisfied and adherent to their treatment plan. Published reports of the prevalence of coprescribing of benzodiazepines and opioids of 1.1 to 2.7% in the general population, may be lower than our veteran population.¹⁴ Despite the fact that nearly 20% of the population had a history of opioid misuse, only 1 patient was terminated from the clinic because of repeated episodes of polysubstance use disorder.

GeriPACT has the capability to be responsive to the changing needs of older chronic pain patients as a learning health system using continuous process improvement with frequent team meetings and interdisciplinary care.¹⁵ Our experience with chronic pain management demonstrates the feasibility and quality of guideline-based management and enhances our understanding of the intersection of care, chronic pain management, and opioid use disorder in older adults.

Limitations

Our experience with this population of older veterans may not be applicable to other geriatric populations. While all patients received their primary care at VA and patients were seen regularly, our data may not account for possible use of some community services, including hospitalization and long-term care.

Conclusions

Guideline-based patient-centered medical home management of patients with chronic pain treated with opioids can be an effective model to maintain and improve measures of health and well-being in older patients. Primary care management is critical in optimizing the prescribing and use of opioids in older adults. These complex older patients are best managed by an interdisciplinary team.

Acknowledgments

This work was supported in part by the Geriatric Workforce Enhancement Program, HRSA Grant: 1-U1Q-HP 033085-01-00.

The United States continues to confront an opioid crisis that also affects older adults. According to the Substance Abuse and Mental Health Services Administration from 1999 to 2010, there has been a 4-fold increase in opioid overdose deaths.¹ Between 2010 and 2015, the rate of opioid-related inpatient stays and emergency department (ED) visits for people aged ≥ 65 years increased by 34% and 74%, respectively, and opioid-related overdose deaths continue to increase among older patients.^1,2

Background

Chronic pain is estimated to affect 50 million US adults.³ Individuals receiving long-term opioid therapy may not have experienced relief with other medications or cannot take them for medical safety reasons. Losing access to opioid prescriptions can contribute to misuse of illicit opioids. Implementing best practices for prescription opioid management in older adults is challenging. Older adults have a high prevalence of chronic pain, which is linked to disability and loss of function, reduced mobility, falls, depression, anxiety, sleep disorders, social isolation, and suicide or suicidal ideation.⁴ Until recently, chronic pain in older adults was often treated primarily with long-term opioid prescriptions, despite little evidence for the effectiveness of that treatment for chronic conditions. The prevalence of long-term opioid use in adults has increased from 1.8% (1999-2000) to 5.4% (2013-2014), and 25% of adult long-term opioid users are aged ≥ 65 years.⁵

Older adults are especially vulnerable to developing adverse events (AEs) from opioid use, including constipation, confusion, nausea, falls, and overdose. These factors make safe prescribing more challenging even when opioids are an appropriate therapeutic choice. Older adults often have multiple chronic conditions and take multiple medications that increase risk of AEs due to drug-disease and drug-drug interactions. Finding appropriate alternatives for pain management can be challenging in the presence of dementia if other pharmacologic options are contraindicated or mobility issues limit access to other therapeutic options.

Pain treatment plans should be based on realistic functional goals using a shared decision-making approach accounting for patient and provider expectations. All reasonable nondrug and nonopioid treatments should be considered before opioids are initiated. A comprehensive, person-centered, approach to pain management in older adults that includes opioids, other medications, and complementary and integrative care could improve both pain control and function,and reduce the harms of unnecessary opioid exposure.⁶ A validated risk review should be performed and documented on all patients starting opioids except patients enrolled in hospice care.

In 2018, the US Department of Veterans Affairs (VA) required all facilities to complete case reviews for veterans identified in the Stratification Tool for Opioid Risk Mitigation (STORM) dashboard as being at particularly high risk for AEs among patients prescribed opioids.⁷ We present our experience with a 1-year management of 48 high-risk older patients receiving chronic prescription opioid therapy. These patients obtained all their care at the VA with complete record documentation.

Methods

The Tennessee Valley Healthcare System (TVHS) is an integrated VA health care system with > 100,000 veteran patients in middle Tennessee with 2 medical centers 40 miles apart, and 12 community-based outpatient clinics. In 2011, TVHS developed a geriatric patient-centered medical home model for geriatric primary care—the geriatric patient aligned care team (GeriPACT).⁸ GeriPACT consists of a GeriPACT primary care provider (geriatrician or geriatric nurse practitioner with a panel of about 800 outpatients), social worker, clinical pharmacist, registered nurse care manager, licensed vocational nurse, and clerical staff. GeriPACT is a special population PACT within primary care for complex geriatric and other high-risk vulnerable veterans providing integrated, interdisciplinary assessment and longitudinal management, and coordination of both VA and non-VA-funded (eg, Medicare and Medicaid) services for patients and caregivers. GeriPACT at the Nashville TVHS campus has an enrollment of 745 patients of whom 48 receive chronic prescription opioid therapy. The practice is supported by the VA Computerized Patients Record System (CPRS), including the electronic patient portal, My healtheVet, with telemedicine capabilities. Data were collected by chart review with operations data extracted from the Veterans Health Information System and Technology Architecture.

Best practices for prescription opioids for chronic pain follow the US Department of Health and Human Services Interagency Task Force pain management recommendations.⁴ These include: (1) Effective pain evaluation and management, including diagnostic evaluation and indicated referrals; (2) appropriately prescribed opioids when indicated; and (3) active management of opioid users to prevent AEs and misuse. Strategies used in GeriPACT were adopted from the pain management task force and designed to address needs and challenges associated with responsible chronic opioid prescribing (Table 1).

Results

Chronic opioid patients comprised 6.4% of the GeriPACT population. These patients had many comorbidities, including diabetes mellitus (35%), pulmonary disease (25%), congestive heart failure (18.8%), and dementia (8%). There were 54% with estimated glomerular filtration rates (eGFR) < 60 mL/min, indicating at least stage 3 chronic kidney disease (Table 2). Patients had an average RIOSORD Score of 21 and a 14% risk of opioid induced respiratory depression, and 20% received mental health services.

The mean CAN score was 83.1, suggesting a 1-year risk of 20% for a major AE and 5% mortality risk. Many patients with chronic opioid use were transferred to GeriPACT from primary care due to presence of complex medical issues in addition to need for chronic pain management. In this population, 8% were coprescribed benzodiazepines and opioids. Consults were obtained from interventional pain for 37.5% of patients and palliative care for 27% of patients, the majority for goals of care related to chronic illness and advance directive discussions, and in 1 patient for pain and symptom management. The majority of patients (81%) had advance care planning documents or discussions documented in the electronic health record, and 87.5% of patients received home and community-based support in addition to GeriPACT care.

Medication Reduction

Pharmacists routinely counseled patients regarding the appropriate timing of refills and made monthly calls to request refills of controlled drugs. Three patients agreed to opioid dose reduction due to improved clinical status. Two patients had 25% and 30% dose reductions, respectively, and 1 patient was able to be discontinue opioids. This was achieved through reduction of therapy and or substitution of alternative nonopioid pain medications. One patient was initiated on a slow benzodiazepine taper schedule after decades of benzodiazepine use in addition to engagement with a whole health coach and primary care mental health integration provider. Another patient was disenrolled from the clinic because of repeated nonadherence and positive UDSs for polysubstance use disorder.

Accidental Overdoses

There were 2 patients with accidental overdoses who survived, both on high morphine equivalent daily doses (MEDDs). One patient was admitted to the intensive care unit for increasing confusion after taking more than the prescribed opioids (120 mg MEDD) due to uncontrolled pain for 2 months following surgery. The second patient was taking 66 mg MEDD with multiple risk factors for respiratory depression (severe chronic obstructive pulmonary disease requiring oxygen, obstructive sleep apnea, and concomitant benzodiazepine use) who repeatedly refused tapering of opioids and benzodiazepines. He was found unresponsive in respiratory depression by home health staff. Both patients had naloxone kits in their home that were not administered.

Urine Drug Screening

There was an occasional negative opioid UDS attributed to patients on a low-dose opioid administered more than 24 hours before. Five patients (10.4%) had positive UDSs. Two patients were positive for cocaine, and because of chronic persistent pain and complex medical problems cared for in the clinic, counseled and continued on therapy with no repeat infractions. Two patients were positive for cannabinoids attributed to CBD oil products, which are legal in Tennessee. One patient had repeated positive UDSs for polysubstance abuse and was terminated from the clinic, preferring to use cannabinoids and other substances illegally. Meperidine, fentanyl, tramadol, and other synthetic opioids are not detected on a routine UDS.

Discussion

Primary care is critical in optimizing the prescribing and use of opioids in older adults. The patient-centered medical home can give health care providers the tools and support to provide evidence—based pain management for their older adult patients and to facilitate prescription and monitoring of appropriate opioid use to minimizing AEs and OUD risk. This includes a reliable health information technology monitoring system as part of a collaborative, person-centered care practice capable of managing frail older patients with multiple chronic conditions as well as social risk factors. GeriPACT was able to implement guideline—based evaluation and treatment of chronic pain patients through optimal management of opioids, risk reduction, and monitoring and management of AEs, misuse, and dose tapering using shared decision-making strategies when appropriate.

Complex older patients on chronic opioid treatment can do well and are best managed by an interdisciplinary team. Our panel had a high prevalence of chronic opioid patients and a high expected mortality based on the severity of comorbidities. Patients had frequent access to care with utilization of many support services. Patients received care for many chronic illnesses at the same time they received opioid therapy and generally were satisfied and adherent to their treatment plan. Published reports of the prevalence of coprescribing of benzodiazepines and opioids of 1.1 to 2.7% in the general population, may be lower than our veteran population.¹⁴ Despite the fact that nearly 20% of the population had a history of opioid misuse, only 1 patient was terminated from the clinic because of repeated episodes of polysubstance use disorder.

GeriPACT has the capability to be responsive to the changing needs of older chronic pain patients as a learning health system using continuous process improvement with frequent team meetings and interdisciplinary care.¹⁵ Our experience with chronic pain management demonstrates the feasibility and quality of guideline-based management and enhances our understanding of the intersection of care, chronic pain management, and opioid use disorder in older adults.

Limitations

Our experience with this population of older veterans may not be applicable to other geriatric populations. While all patients received their primary care at VA and patients were seen regularly, our data may not account for possible use of some community services, including hospitalization and long-term care.

Conclusions

Guideline-based patient-centered medical home management of patients with chronic pain treated with opioids can be an effective model to maintain and improve measures of health and well-being in older patients. Primary care management is critical in optimizing the prescribing and use of opioids in older adults. These complex older patients are best managed by an interdisciplinary team.

Acknowledgments

This work was supported in part by the Geriatric Workforce Enhancement Program, HRSA Grant: 1-U1Q-HP 033085-01-00.

Parkinson disease (PD) is the second most common neurodegenerative disorder after Alzheimer disease.¹ Age-standardized incidence rates of PD in population-based studies in Europe and the United States range from 8.6 to 19.0 per 100,000 individuals, using a strict diagnostic criterion for PD.² The negative impact of PD on health-related quality of life imposes a heavy burden on veterans. According to the US Department of Veterans Affairs (VA) National Parkinson’s Disease Consortium, the VA has as many as 50,000 patients with PD under its care. Because of this demand, the VA has strived to revolutionize available services for veterans with PD and related movement disorders.³

The classic motor symptoms of resting tremors, bradykinesia, postural instability, and rigidity of this progressive neurodegenerative disorder is a significant cause of functional limitations that lead to increased falls and inability to perform activities of daily living that challenges the individual and caregiver. ⁴ Rehabilitation has been considered as an adjuvant to surgical and medical treatments for PD to maximize function and minimize complications. High-intensity multimodal exercise boot camps and therapy that focuses on intensely exercising high-amplitude movements, have been shown to improve motor performance in PD.^5,6 Available evidence has shown that exercise-dependent plasticity is the main mechanism underlying the effects of physiotherapy because it increases synaptic strength and affects neurotransmission.⁷ Although there is no consensus on the optimal approach for rehabilitation, innovative techniques have been proposed and studied. One such approach involves virtual reality (VR), which has begun to attract attention for its potential use during rehabilitation.⁸

VR is a simulated experience created by computer-based technology that grants users access to a virtual environment. There are 2 categories of VR: immersive and nonimmersive. Immersive VR is the most direct experience of virtual environments and usually is implemented through a head-mounted display. These displays have monitors in front of each eye, which can provide monocular or biocular imaging with the most common display being small liquid crystal display (LCD) panels.

Nonimmersive VR typically allows a participant to view a virtual environment by using standard high-resolution monitors rather than a headset or an immersive screen room. Many systems are readily available to the general public as electronic interactive entertainment (ie, video games). Interaction with the virtual world happens through interfaces such as keyboards and controllers while viewing a television or computer monitor. These systems often are more accessible and affordable when compared with immersive VR, although this is changing rapidly.

VR therapy is a noninvasive therapeutic alternative modality for PD. This review aims to study the use of VR to treat PD from a rehabilitative standpoint. Although not the only review on the topic, this systematic review is the first to examine the differences between immersive and nonimmersive VR rehabilitation for PD. VR technology is evolving rapidly and the research behind its clinical applications is steadily growing, especially as accessibility improves. This review also is an updated summary of the current literature on the effectiveness of VR therapy during PD rehabilitation.

Methods

Starting in July 2019, the authors searched several databases (PubMed, Google Scholar, Cochrane, and the Physiotherapy Evidence Database [PEDro]) for articles by using the keyword “Parkinson’s disease” combined with either “virtual reality” or “video games.” To find studies specific to rehabilitation, searches included the additional keyword: “rehabilitation.” After compiling an initial set of 89 articles, titles were reviewed to eliminate duplicates. The authors then read the abstracts to exclude study protocols, systematic reviews, and studies that used VR but did not focus on PD or any therapeutic outcome.

Articles were sorted into immersive or nonimmersive virtual reality categories. To be included as immersive VR, studies had to use any type of VR headset or full-scale VR room. Anything less immersive or similar to a traditional video game was included in the nonimmersive VR category. Articles that met inclusion criteria were selected for the systematic review. Criteria for inclusion in this review were: (1) English language; (2) included a study population focused on PD; (3) used some form of VR therapy; and (4) assessed potential rehabilitation by quantitative outcome measures. Only articles published in peer-reviewed journals were included.

Data were extracted into 2 tables specifically modified for this review: immersive and nonimmersive VR. Extracted data included study author name and publication date, study design, methodologic quality, sample size and group allocation, symptom progression via the Hoehn and Yahr Scale (1 to 5), VR modality, presence of control groups, primary outcomes, and primary findings.

Results

This review is reported according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PRISMA).¹⁰ After screening and assessment, 28 articles met inclusion criteria for this review: 7 using immersive VR and 21 using nonimmersive VR (Figure). The immersive studies included 2 RCTs (both with PEDro scores of 5), 1 controlled study with a PEDro score of 5, 1 pre-post pilot study, and 3 cohort studies (Table 2). The nonimmersive studies included 13 RCTs with an average PEDro score of 5.8; 2 pre-post pilot studies, 1 repeated measures study with a historic control, 1 non-RCT, 2 pre-post prospective studies, and 2 cohort studies (1 retrospective and 1 prospective) (Table 3).

Several outcome and assessment tools were used; the most common measures were related to gait, balance, kinematics, and VR feasibility. Studies varied in VR modalities and protocol, ranging from 21 sessions of Nintendo Wii Fit gaming for 7 weeks to 1 session of VR headset use.

Immersive VR

There were fewer immersive VR studies and these studies had lower mean PEDro scores when compared with nonimmersive VR studies. The VR modalities in the immersive studies used a VR headset or a multisensory immersive system that included polarized glasses. All the studies showed positive improvement in primary outcomes with the exception of Ma and colleagues,which showed no difference in success rates or kinematics with moving balls, and only showed improvement in reaching for stationary balls.¹¹ The mean number of participants in the studies was 18.4.

All 7 studies had each participant complete tasks without VR then with the VR therapy. None of the studies compared immersive VR therapy with more conventional therapies. Robles-Garcia and colleagues compared 2 VR groups where the experimental group imitated an avatar’s finger tapping in the VR system while the control group lacked this imitation.¹² The authors found that adding that imitation to the VR group lead to an increase in movement amplitude.

Among the immersive VR studies, only Janeh and colleagues commented on possible adverse effects (AEs) and found that VR was a safe method without AEs of discomfort or simulator sickness.¹³ The other 6 studies did not make any mention or discussion of AEs related to the training.

Nonimmersive VR

VR modalities used in nonimmersive studies included consumer video gaming systems. Nintendo Wii and Microsoft Xbox Kinect were most commonly used. Among the 21 studies, 14 compared VR therapy with a type of traditional exercise (eg, treadmill training, stretching exercises, balance training). The mean number of participants of the studies was 28.3.

Five studies showed a difference between the VR and traditional training groups.^14-18 However, 9 studies showed positive improvement in both groups and found no between-group differences.^19-25 Among the remaining 7 studies, all showed improvement in primary outcomes after adding VR interventional therapy. In 1 RCT, 3 groups were compared (no intervention, Nintendo Wii, and Xbox Kinect) for gait tests, anxiety levels, memory, and attention.²⁶ The authors found that only the Nintendo Wii group showed improvement in outcomes. A prospective cohort study was the only one to compare different doses of VR therapy (10 sessions vs 15 sessions of Nintendo Wii Fit).²⁷ The authors found that both groups demonstrated the same amount of improvement on balance performances with no group effect.

Ten studiesreported no AEs during the training, but also did not define what was considered an AE.^{15,16,19,22-25,27-29} Eight studies did not make any mention of AEs.^{14,17,21,26,27,30-32} Yen and colleagues reported no AEs during training except for the patients’ tendency to fall.²⁰ However, therapists supervised the patients to avoid falls and no falls occurred. Nuic and colleaguesreported 3 serious AEs, unrelated to the training: severe pneumonia (n = 1) and deep-brain stimulation generator replacement (n = 2).³³ During the video game training sessions no specific AEs occurred. Only Pompeu and colleagues defined an AE as any untoward medical occurrence such as convulsion, syncope, dizziness, vertigo, falls, or any medical condition that required hospitalization or disability.³⁴ One researcher registered the occurrence of any AE; however, none occurred during the study period.

Discussion

This systematic review demonstrates that VR therapy is a promising addition to rehabilitation for PD. Evidence supporting VR therapy is limited, but is continually expanding, and current evidence has shown improvement in assessments and rehabilitative outcomes involving PD. Most nonimmersive studies have shown that VR therapy does not lead to better outcomes when compared with traditional therapy but also is not harmful and does provide similar improvement. Immersive VR studies, on the other hand, have not compared therapy with conventional training extensively, and tend to focus more on time for task completion or movement.

There were fewer immersive VR studies than nonimmersive VR studies. This could be because of the increased technological difficulty and demand to correctly execute immersive VR modalities, as well as the—until recently—substantial expense. This might be another reason why the mean PEDro scores for immersive VR RCTs were lower than the mean scores found in nonimmersive RCTs.

Limitations

This review was limited by several factors related to the included studies. A variety of rating scales were used in the immersive and nonimmersive VR studies. Although there was some general overlap with common measurements such as gait, balance, kinematics, and VR feasibility, no studies had the same primary and secondary outcomes. Such heterogeneity in protocols and outcomes limited our ability to draw conclusions from these differing studies. Additionally, the average number of participants of both immersive and nonimmersive studies were small and the statistical significance of findings should be interpreted with caution. Finally, VR devices and systems differed between studies, further limiting comparisons. Although these factors limit this systematic review, we can still identify treatment and research implications. Adequately powered future studies with standardized protocols would further improve the available evidence and support for VR as an intervention.

Conclusions

VR therapy is a promising rehabilitation modality for PD. Additional investigations of VR therapy and PD should include direct comparisons between immersive and nonimmersive VR therapies. It could be hypothesized that the greater immersion and engagement potential of immersive VR would demonstrate greater functional improvement compared with nonimmersive VR, but there is no data to support this for PD. VR therapy for PD appears to be a relatively safe alternative or adjunct to traditional therapy with a potentially positive impact on a variety of symptoms and is growing as an innovative therapeutic approach for PD patients.

Parkinson disease (PD) is the second most common neurodegenerative disorder after Alzheimer disease.¹ Age-standardized incidence rates of PD in population-based studies in Europe and the United States range from 8.6 to 19.0 per 100,000 individuals, using a strict diagnostic criterion for PD.² The negative impact of PD on health-related quality of life imposes a heavy burden on veterans. According to the US Department of Veterans Affairs (VA) National Parkinson’s Disease Consortium, the VA has as many as 50,000 patients with PD under its care. Because of this demand, the VA has strived to revolutionize available services for veterans with PD and related movement disorders.³

The classic motor symptoms of resting tremors, bradykinesia, postural instability, and rigidity of this progressive neurodegenerative disorder is a significant cause of functional limitations that lead to increased falls and inability to perform activities of daily living that challenges the individual and caregiver. ⁴ Rehabilitation has been considered as an adjuvant to surgical and medical treatments for PD to maximize function and minimize complications. High-intensity multimodal exercise boot camps and therapy that focuses on intensely exercising high-amplitude movements, have been shown to improve motor performance in PD.^5,6 Available evidence has shown that exercise-dependent plasticity is the main mechanism underlying the effects of physiotherapy because it increases synaptic strength and affects neurotransmission.⁷ Although there is no consensus on the optimal approach for rehabilitation, innovative techniques have been proposed and studied. One such approach involves virtual reality (VR), which has begun to attract attention for its potential use during rehabilitation.⁸

VR is a simulated experience created by computer-based technology that grants users access to a virtual environment. There are 2 categories of VR: immersive and nonimmersive. Immersive VR is the most direct experience of virtual environments and usually is implemented through a head-mounted display. These displays have monitors in front of each eye, which can provide monocular or biocular imaging with the most common display being small liquid crystal display (LCD) panels.

Nonimmersive VR typically allows a participant to view a virtual environment by using standard high-resolution monitors rather than a headset or an immersive screen room. Many systems are readily available to the general public as electronic interactive entertainment (ie, video games). Interaction with the virtual world happens through interfaces such as keyboards and controllers while viewing a television or computer monitor. These systems often are more accessible and affordable when compared with immersive VR, although this is changing rapidly.

VR therapy is a noninvasive therapeutic alternative modality for PD. This review aims to study the use of VR to treat PD from a rehabilitative standpoint. Although not the only review on the topic, this systematic review is the first to examine the differences between immersive and nonimmersive VR rehabilitation for PD. VR technology is evolving rapidly and the research behind its clinical applications is steadily growing, especially as accessibility improves. This review also is an updated summary of the current literature on the effectiveness of VR therapy during PD rehabilitation.

Methods

Starting in July 2019, the authors searched several databases (PubMed, Google Scholar, Cochrane, and the Physiotherapy Evidence Database [PEDro]) for articles by using the keyword “Parkinson’s disease” combined with either “virtual reality” or “video games.” To find studies specific to rehabilitation, searches included the additional keyword: “rehabilitation.” After compiling an initial set of 89 articles, titles were reviewed to eliminate duplicates. The authors then read the abstracts to exclude study protocols, systematic reviews, and studies that used VR but did not focus on PD or any therapeutic outcome.

Articles were sorted into immersive or nonimmersive virtual reality categories. To be included as immersive VR, studies had to use any type of VR headset or full-scale VR room. Anything less immersive or similar to a traditional video game was included in the nonimmersive VR category. Articles that met inclusion criteria were selected for the systematic review. Criteria for inclusion in this review were: (1) English language; (2) included a study population focused on PD; (3) used some form of VR therapy; and (4) assessed potential rehabilitation by quantitative outcome measures. Only articles published in peer-reviewed journals were included.

Data were extracted into 2 tables specifically modified for this review: immersive and nonimmersive VR. Extracted data included study author name and publication date, study design, methodologic quality, sample size and group allocation, symptom progression via the Hoehn and Yahr Scale (1 to 5), VR modality, presence of control groups, primary outcomes, and primary findings.

Results

This review is reported according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PRISMA).¹⁰ After screening and assessment, 28 articles met inclusion criteria for this review: 7 using immersive VR and 21 using nonimmersive VR (Figure). The immersive studies included 2 RCTs (both with PEDro scores of 5), 1 controlled study with a PEDro score of 5, 1 pre-post pilot study, and 3 cohort studies (Table 2). The nonimmersive studies included 13 RCTs with an average PEDro score of 5.8; 2 pre-post pilot studies, 1 repeated measures study with a historic control, 1 non-RCT, 2 pre-post prospective studies, and 2 cohort studies (1 retrospective and 1 prospective) (Table 3).

Several outcome and assessment tools were used; the most common measures were related to gait, balance, kinematics, and VR feasibility. Studies varied in VR modalities and protocol, ranging from 21 sessions of Nintendo Wii Fit gaming for 7 weeks to 1 session of VR headset use.

Immersive VR

There were fewer immersive VR studies and these studies had lower mean PEDro scores when compared with nonimmersive VR studies. The VR modalities in the immersive studies used a VR headset or a multisensory immersive system that included polarized glasses. All the studies showed positive improvement in primary outcomes with the exception of Ma and colleagues,which showed no difference in success rates or kinematics with moving balls, and only showed improvement in reaching for stationary balls.¹¹ The mean number of participants in the studies was 18.4.

All 7 studies had each participant complete tasks without VR then with the VR therapy. None of the studies compared immersive VR therapy with more conventional therapies. Robles-Garcia and colleagues compared 2 VR groups where the experimental group imitated an avatar’s finger tapping in the VR system while the control group lacked this imitation.¹² The authors found that adding that imitation to the VR group lead to an increase in movement amplitude.

Among the immersive VR studies, only Janeh and colleagues commented on possible adverse effects (AEs) and found that VR was a safe method without AEs of discomfort or simulator sickness.¹³ The other 6 studies did not make any mention or discussion of AEs related to the training.

Nonimmersive VR

VR modalities used in nonimmersive studies included consumer video gaming systems. Nintendo Wii and Microsoft Xbox Kinect were most commonly used. Among the 21 studies, 14 compared VR therapy with a type of traditional exercise (eg, treadmill training, stretching exercises, balance training). The mean number of participants of the studies was 28.3.

Five studies showed a difference between the VR and traditional training groups.^14-18 However, 9 studies showed positive improvement in both groups and found no between-group differences.^19-25 Among the remaining 7 studies, all showed improvement in primary outcomes after adding VR interventional therapy. In 1 RCT, 3 groups were compared (no intervention, Nintendo Wii, and Xbox Kinect) for gait tests, anxiety levels, memory, and attention.²⁶ The authors found that only the Nintendo Wii group showed improvement in outcomes. A prospective cohort study was the only one to compare different doses of VR therapy (10 sessions vs 15 sessions of Nintendo Wii Fit).²⁷ The authors found that both groups demonstrated the same amount of improvement on balance performances with no group effect.

Ten studiesreported no AEs during the training, but also did not define what was considered an AE.^{15,16,19,22-25,27-29} Eight studies did not make any mention of AEs.^{14,17,21,26,27,30-32} Yen and colleagues reported no AEs during training except for the patients’ tendency to fall.²⁰ However, therapists supervised the patients to avoid falls and no falls occurred. Nuic and colleaguesreported 3 serious AEs, unrelated to the training: severe pneumonia (n = 1) and deep-brain stimulation generator replacement (n = 2).³³ During the video game training sessions no specific AEs occurred. Only Pompeu and colleagues defined an AE as any untoward medical occurrence such as convulsion, syncope, dizziness, vertigo, falls, or any medical condition that required hospitalization or disability.³⁴ One researcher registered the occurrence of any AE; however, none occurred during the study period.

Discussion

This systematic review demonstrates that VR therapy is a promising addition to rehabilitation for PD. Evidence supporting VR therapy is limited, but is continually expanding, and current evidence has shown improvement in assessments and rehabilitative outcomes involving PD. Most nonimmersive studies have shown that VR therapy does not lead to better outcomes when compared with traditional therapy but also is not harmful and does provide similar improvement. Immersive VR studies, on the other hand, have not compared therapy with conventional training extensively, and tend to focus more on time for task completion or movement.

There were fewer immersive VR studies than nonimmersive VR studies. This could be because of the increased technological difficulty and demand to correctly execute immersive VR modalities, as well as the—until recently—substantial expense. This might be another reason why the mean PEDro scores for immersive VR RCTs were lower than the mean scores found in nonimmersive RCTs.

Limitations

This review was limited by several factors related to the included studies. A variety of rating scales were used in the immersive and nonimmersive VR studies. Although there was some general overlap with common measurements such as gait, balance, kinematics, and VR feasibility, no studies had the same primary and secondary outcomes. Such heterogeneity in protocols and outcomes limited our ability to draw conclusions from these differing studies. Additionally, the average number of participants of both immersive and nonimmersive studies were small and the statistical significance of findings should be interpreted with caution. Finally, VR devices and systems differed between studies, further limiting comparisons. Although these factors limit this systematic review, we can still identify treatment and research implications. Adequately powered future studies with standardized protocols would further improve the available evidence and support for VR as an intervention.

Conclusions

VR therapy is a promising rehabilitation modality for PD. Additional investigations of VR therapy and PD should include direct comparisons between immersive and nonimmersive VR therapies. It could be hypothesized that the greater immersion and engagement potential of immersive VR would demonstrate greater functional improvement compared with nonimmersive VR, but there is no data to support this for PD. VR therapy for PD appears to be a relatively safe alternative or adjunct to traditional therapy with a potentially positive impact on a variety of symptoms and is growing as an innovative therapeutic approach for PD patients.

Parkinson disease (PD) is the second most common neurodegenerative disorder after Alzheimer disease.¹ Age-standardized incidence rates of PD in population-based studies in Europe and the United States range from 8.6 to 19.0 per 100,000 individuals, using a strict diagnostic criterion for PD.² The negative impact of PD on health-related quality of life imposes a heavy burden on veterans. According to the US Department of Veterans Affairs (VA) National Parkinson’s Disease Consortium, the VA has as many as 50,000 patients with PD under its care. Because of this demand, the VA has strived to revolutionize available services for veterans with PD and related movement disorders.³

The classic motor symptoms of resting tremors, bradykinesia, postural instability, and rigidity of this progressive neurodegenerative disorder is a significant cause of functional limitations that lead to increased falls and inability to perform activities of daily living that challenges the individual and caregiver. ⁴ Rehabilitation has been considered as an adjuvant to surgical and medical treatments for PD to maximize function and minimize complications. High-intensity multimodal exercise boot camps and therapy that focuses on intensely exercising high-amplitude movements, have been shown to improve motor performance in PD.^5,6 Available evidence has shown that exercise-dependent plasticity is the main mechanism underlying the effects of physiotherapy because it increases synaptic strength and affects neurotransmission.⁷ Although there is no consensus on the optimal approach for rehabilitation, innovative techniques have been proposed and studied. One such approach involves virtual reality (VR), which has begun to attract attention for its potential use during rehabilitation.⁸

VR is a simulated experience created by computer-based technology that grants users access to a virtual environment. There are 2 categories of VR: immersive and nonimmersive. Immersive VR is the most direct experience of virtual environments and usually is implemented through a head-mounted display. These displays have monitors in front of each eye, which can provide monocular or biocular imaging with the most common display being small liquid crystal display (LCD) panels.

Nonimmersive VR typically allows a participant to view a virtual environment by using standard high-resolution monitors rather than a headset or an immersive screen room. Many systems are readily available to the general public as electronic interactive entertainment (ie, video games). Interaction with the virtual world happens through interfaces such as keyboards and controllers while viewing a television or computer monitor. These systems often are more accessible and affordable when compared with immersive VR, although this is changing rapidly.

VR therapy is a noninvasive therapeutic alternative modality for PD. This review aims to study the use of VR to treat PD from a rehabilitative standpoint. Although not the only review on the topic, this systematic review is the first to examine the differences between immersive and nonimmersive VR rehabilitation for PD. VR technology is evolving rapidly and the research behind its clinical applications is steadily growing, especially as accessibility improves. This review also is an updated summary of the current literature on the effectiveness of VR therapy during PD rehabilitation.

Methods

Starting in July 2019, the authors searched several databases (PubMed, Google Scholar, Cochrane, and the Physiotherapy Evidence Database [PEDro]) for articles by using the keyword “Parkinson’s disease” combined with either “virtual reality” or “video games.” To find studies specific to rehabilitation, searches included the additional keyword: “rehabilitation.” After compiling an initial set of 89 articles, titles were reviewed to eliminate duplicates. The authors then read the abstracts to exclude study protocols, systematic reviews, and studies that used VR but did not focus on PD or any therapeutic outcome.

Articles were sorted into immersive or nonimmersive virtual reality categories. To be included as immersive VR, studies had to use any type of VR headset or full-scale VR room. Anything less immersive or similar to a traditional video game was included in the nonimmersive VR category. Articles that met inclusion criteria were selected for the systematic review. Criteria for inclusion in this review were: (1) English language; (2) included a study population focused on PD; (3) used some form of VR therapy; and (4) assessed potential rehabilitation by quantitative outcome measures. Only articles published in peer-reviewed journals were included.

Data were extracted into 2 tables specifically modified for this review: immersive and nonimmersive VR. Extracted data included study author name and publication date, study design, methodologic quality, sample size and group allocation, symptom progression via the Hoehn and Yahr Scale (1 to 5), VR modality, presence of control groups, primary outcomes, and primary findings.

Results

This review is reported according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PRISMA).¹⁰ After screening and assessment, 28 articles met inclusion criteria for this review: 7 using immersive VR and 21 using nonimmersive VR (Figure). The immersive studies included 2 RCTs (both with PEDro scores of 5), 1 controlled study with a PEDro score of 5, 1 pre-post pilot study, and 3 cohort studies (Table 2). The nonimmersive studies included 13 RCTs with an average PEDro score of 5.8; 2 pre-post pilot studies, 1 repeated measures study with a historic control, 1 non-RCT, 2 pre-post prospective studies, and 2 cohort studies (1 retrospective and 1 prospective) (Table 3).

Several outcome and assessment tools were used; the most common measures were related to gait, balance, kinematics, and VR feasibility. Studies varied in VR modalities and protocol, ranging from 21 sessions of Nintendo Wii Fit gaming for 7 weeks to 1 session of VR headset use.

Immersive VR

There were fewer immersive VR studies and these studies had lower mean PEDro scores when compared with nonimmersive VR studies. The VR modalities in the immersive studies used a VR headset or a multisensory immersive system that included polarized glasses. All the studies showed positive improvement in primary outcomes with the exception of Ma and colleagues,which showed no difference in success rates or kinematics with moving balls, and only showed improvement in reaching for stationary balls.¹¹ The mean number of participants in the studies was 18.4.

All 7 studies had each participant complete tasks without VR then with the VR therapy. None of the studies compared immersive VR therapy with more conventional therapies. Robles-Garcia and colleagues compared 2 VR groups where the experimental group imitated an avatar’s finger tapping in the VR system while the control group lacked this imitation.¹² The authors found that adding that imitation to the VR group lead to an increase in movement amplitude.

Among the immersive VR studies, only Janeh and colleagues commented on possible adverse effects (AEs) and found that VR was a safe method without AEs of discomfort or simulator sickness.¹³ The other 6 studies did not make any mention or discussion of AEs related to the training.

Nonimmersive VR

VR modalities used in nonimmersive studies included consumer video gaming systems. Nintendo Wii and Microsoft Xbox Kinect were most commonly used. Among the 21 studies, 14 compared VR therapy with a type of traditional exercise (eg, treadmill training, stretching exercises, balance training). The mean number of participants of the studies was 28.3.

Five studies showed a difference between the VR and traditional training groups.^14-18 However, 9 studies showed positive improvement in both groups and found no between-group differences.^19-25 Among the remaining 7 studies, all showed improvement in primary outcomes after adding VR interventional therapy. In 1 RCT, 3 groups were compared (no intervention, Nintendo Wii, and Xbox Kinect) for gait tests, anxiety levels, memory, and attention.²⁶ The authors found that only the Nintendo Wii group showed improvement in outcomes. A prospective cohort study was the only one to compare different doses of VR therapy (10 sessions vs 15 sessions of Nintendo Wii Fit).²⁷ The authors found that both groups demonstrated the same amount of improvement on balance performances with no group effect.

Ten studiesreported no AEs during the training, but also did not define what was considered an AE.^{15,16,19,22-25,27-29} Eight studies did not make any mention of AEs.^{14,17,21,26,27,30-32} Yen and colleagues reported no AEs during training except for the patients’ tendency to fall.²⁰ However, therapists supervised the patients to avoid falls and no falls occurred. Nuic and colleaguesreported 3 serious AEs, unrelated to the training: severe pneumonia (n = 1) and deep-brain stimulation generator replacement (n = 2).³³ During the video game training sessions no specific AEs occurred. Only Pompeu and colleagues defined an AE as any untoward medical occurrence such as convulsion, syncope, dizziness, vertigo, falls, or any medical condition that required hospitalization or disability.³⁴ One researcher registered the occurrence of any AE; however, none occurred during the study period.

Discussion

This systematic review demonstrates that VR therapy is a promising addition to rehabilitation for PD. Evidence supporting VR therapy is limited, but is continually expanding, and current evidence has shown improvement in assessments and rehabilitative outcomes involving PD. Most nonimmersive studies have shown that VR therapy does not lead to better outcomes when compared with traditional therapy but also is not harmful and does provide similar improvement. Immersive VR studies, on the other hand, have not compared therapy with conventional training extensively, and tend to focus more on time for task completion or movement.

There were fewer immersive VR studies than nonimmersive VR studies. This could be because of the increased technological difficulty and demand to correctly execute immersive VR modalities, as well as the—until recently—substantial expense. This might be another reason why the mean PEDro scores for immersive VR RCTs were lower than the mean scores found in nonimmersive RCTs.

Limitations

This review was limited by several factors related to the included studies. A variety of rating scales were used in the immersive and nonimmersive VR studies. Although there was some general overlap with common measurements such as gait, balance, kinematics, and VR feasibility, no studies had the same primary and secondary outcomes. Such heterogeneity in protocols and outcomes limited our ability to draw conclusions from these differing studies. Additionally, the average number of participants of both immersive and nonimmersive studies were small and the statistical significance of findings should be interpreted with caution. Finally, VR devices and systems differed between studies, further limiting comparisons. Although these factors limit this systematic review, we can still identify treatment and research implications. Adequately powered future studies with standardized protocols would further improve the available evidence and support for VR as an intervention.

Conclusions

VR therapy is a promising rehabilitation modality for PD. Additional investigations of VR therapy and PD should include direct comparisons between immersive and nonimmersive VR therapies. It could be hypothesized that the greater immersion and engagement potential of immersive VR would demonstrate greater functional improvement compared with nonimmersive VR, but there is no data to support this for PD. VR therapy for PD appears to be a relatively safe alternative or adjunct to traditional therapy with a potentially positive impact on a variety of symptoms and is growing as an innovative therapeutic approach for PD patients.

Surgical treatment of degenerative lumbar spine disease has been rising steadily in the United States, and an increasing fraction of surgery involves lumbar fusion.^1,2 Various techniques are used to accomplish a lumbar fusion, including noninstrumented fusion, anterior lumbar interbody fusion (ALIF), lateral lumbar interbody fusion (XLIF, OLIF), posterior pedicle screw fusion, posterior cortical screw fusion, posterior interbody fusion (TLIF, PLIF), and interspinous process fusion. Rigid, metallic fusion hardware provides high stability and fusion rates, but it likely leads to stress shielding and adjacent segment disease.³ There is interest in less rigid and dynamic stabilization techniques to reduce the risk of adjacent segment disease, such as polyetheretherketone (PEEK) rods, which have been available since 2007. However, literature regarding PEEK rod utility is sparse and of mixed outcomes.^3,4 Additional patient reported outcome (PRO) information would be useful to both surgeons and patients. Using institutional data, this review was designed to examine our experience with PEEK rod lumbar fusion and to document PROs.

Methods

The study was approved by the institutional review board at the US Department of Veterans Affairs (VA) Portland Health Care System (VAPHCS) in Oregon with a waiver of authorization. In this retrospective, single center study, data were queried from the senior author’s (DAR) case logs from VA Computerized Patient Record System (CPRS). Electronic medical records, imaging, and PROs of all consecutive patients undergoing lumbar fusion at 1 or 2 levels with PEEK rods for degenerative disease were retrospectively reviewed. Cases of trauma, malignancy, or infection were excluded. From March 2011 through October 2019, 108 patients underwent lumbar fusion with PEEK rods.

Surgeries were conducted on a Mizuho OSI Jackson Table via bilateral 3 to 4 cm Wiltse incisions using the Medtronic Quadrant retractor system. Medtronic O-Arm images were acquired and delivered to a Medtronic Stealth Station for navigation of the screws. Monopolar coagulation was not used. PEEK pedicle screws were placed and verified with a second O-Arm spin before placing lordotic PEEK rods in the screw heads. No attempt was made to reduce any spondylolisthesis, but distraction was used to open the foramina and indirectly decompress the canal. An interbody device was placed only in treatment of multiply recurrent disc protrusion. After decortication of the transverse processes and facets, intertransverse fusion constructs consisting of calcium hydroxyapatite soaked in autologous bone marrow blood and wrapped in 6-mg bone morphogenetic protein-soaked sponges were placed on the bone. If canal decompression was indicated, a Medtronic Metrx retractor tube was then placed through one of the incisions and decompression carried out. Wounds were closed with absorbable suture. No bracing was used postoperatively. Figure 1 shows a typical single level PEEK rod fusion construct.

Statistical Analysis

Pre- and postoperative pairwise t tests were completed for patients with a complete data, using SAS 9.2 statistical package. Data are presented as standard deviation (SD) of the mean.

Results

Following application of the inclusion/exclusion criteria, 108 patients had undergone lumbar fusion with PEEK rods. Mean (SD) patient age was 60.2 (10.3) years and 88 patients were male (Table 1). Most surgeries were at L5-S1 and L4-5. There were 97 single-level fusions and 11 bilevel fusions. Seventy-four procedures were for spondylolisthesis, 23 for foraminal stenosis, 5 for degenerative disc disease, 3 for coronal imbalance with foraminal stenosis, 2 for pseudarthrosis after surgery elsewhere, and 1 for multiple recurrent disc herniation (Table 2). Twenty-five patients (23.1%) were current tobacco users and 28 (25.9%) were former smokers, 26 (24.1%) had diabetes mellitus (DM), 16 (14.8%) had low bone density by dual energy X-ray absorptiometry (DEXA) imaging, 35 (32.4%) had depression, and 7 (6.5%) were taking an immunosuppressive agent (chronic steroids, biological response modifiers, or methotrexate). Mean body mass index was 30.1.

Surgical Procedure

Of the 108 patients, the first 18 underwent a procedure with fluoroscopic guidance and the Medtronic FluoroNav and Stealth Systems. The next 90 patients underwent a procedure with O-Arm intraoperative CT scanning and Stealth frameless stereotactic navigation. The mean (SD) length of stay was 1.7 (1.3) days. There were no wound infections and no new neurologic deficits. Mean (SD) follow up time was 30.3 (21.8) months.

Imaging

Final imaging was by radiograph in 73 patients, CT in 31, and magnetic resonance imaging (MRI) in 3 (1 patient had no imaging). Sixty-seven patients (62.0%) had a bilateral arthrodesis, and 15 (13.9%) had at least a unilateral arthrodesis. MRI was not used to assess arthrodesis. Eight patients (7.4%) had no definite arthrodesis. Seventeen patients had inadequate or early imaging from which a fusion determination could not be made. Of 81 patients with > 11 months of follow up, 58 (71.6%) had a bilateral arthrodesis, 12 (14.8%) had a unilateral arthrodesis, 8 (9.9%) had no arthrodesis, and 3 (3.7%) were indeterminate.

No patient had any revision fusion surgery at the index level during follow up. Two patients had adjacent level fusions at 27 and 60 months after the index procedure. One patient had a laminectomy at an adjacent segment at 18 months postfusion, and 1 had a foraminotomy at an adjacent segment 89 months post fusion (Figure 3). Overall, there were 4 (3.7%) adjacent segment surgeries at a mean of 48.5 months after surgery. One patient had a sacro-iliac joint fusion below an L5-S1 fusion 17 months prior for persisting pain after the fusion procedure.

Patient Reported Outcomes

Preoperative SF-36 PF and ODI scores were available for 81 patients (Table 3). Postoperative SF-36 PF scores were obtained at 3 months for 65 of these patients, and at 1 year for 63 patients. Postoperative ODI scores were obtained at 3 months for 65 patients, and at 1 year for 55 patients. Among the 65 patients with completed SF-36 scores at 3 months, a mean increase of 22.4 (95% CI, 17-27; P < .001) was noted, and for the 63 patients at 1 year a mean increase of 30.3 (95% CI, 25-35; P < .001) was noted. Among the 65 patients with completed ODI scores at 3 months, a mean decrease of 6.8 (95% CI, 4.9-8.6; P < .001) was noted, and for the 55 patients with completed ODI scores at 1 year a mean decrease of 10.3 (n = 55; 95% CI, 8.4-12.2; P < .001) was noted.

Cost

We compared the hardware cost of a single level construct consisting of 4 pedicle screws, 4 locking caps, and 2 rods using a PEEK system with that of 2 other titanium construct systems. At VAPHCS, the PEEK system cost was about 71% of the cost of 2 other titanium construct systems and 62% of the cost when compared with Medtronic titanium rods.

Discussion

PEEK is useful for spine and cranial implants. It is inert and fully biocompatible with a modulus of elasticity between that of cortical and cancellous bone, and much lower than that of titanium, and is therefore considered to be semirigid.^3,4,6 PEEK rods are intermediate in stiffness between titanium rods (110 Gigapascals) and dynamic devices such as the Zimmer Biomet DYNESYS dynamic stabilization system or the Premia Spine TOPS system.³ Carbon fiber rods and carbon fiber reinforced PEEK implants are other semirigid rod alternatives.^7,8 PEEK rods for posterior lumbar fusion surgery were introduced in 2007. Li and colleagues provide a thorough review of the biomechanical properties of PEEK rods.³

PEEK is thought to have several advantages when compared with titanium. These advantages include more physiologic load sharing and reduction in stress shielding, improved durability, reduced risk of failure in osteoporotic bone, less wear debris, no change in bone forming environment, and imaging radiolucency.^4,9 Spinal PEEK cages have been reported to allow more uniform radiation dose distribution compared with metal constructs, an advantage that also may pertain to PEEK rods.¹⁰ Disadvantages of PEEK rods include an inability to detect rod breakage easily, lack of data on the use in more than minimally unstable clinical situations, and greater expense, although this was not the authors’ observation.^3,4,11

Importantly, it has been reported that PEEK rods permit a greater range of motion in all planes when compared with titanium rods.⁹ Polyetheretherketone rods unload the bone screw interface and increased the anterior column load to a more physiologic 75% when compared with titanium rods.^6,9 However, in another biomechanical study that compared titanium rods, PEEK rods, and a dynamic stabilization device, it was reported that anterior load sharing was 55%, 59%, and 75%, respectively.¹² This indicated that PEEK rods are closer to metal rods than truly dynamic devices for anterior load sharing. The endurance limit of a PEEK rod construct was similar to that of clinically useful metal systems.⁹ PEEK rods resulted in no increase in postfatigue motion compared with titanium rods in a biomechanical model.¹³ Intradiscal pressures at PEEK instrumented segments were similar to uninstrumented segments and greater than those with titanium rod constructs.¹⁴ Intradiscal pressures at adjacent segments were highest with dynamic devices, intermediate with semirigid rods, and lowest with rigid constructs; however, stress values at adjacent segments were lower in PEEK than titanium constructs in any direction of motion.^15,16

Fusion Rates

The use of PEEK rods in lumbar fusion has been reported previously.^3,4,17,18 However, these studies featured small sample sizes, short follow up times, and contradictory results.⁴ Of 8 outcome reports found in a systematic review, 2 studies reported on procedures designed to create nonfusion outcomes (a third similar trial from 2013 was not included in the systematic review), and 1 study reported only on the condition of PEEK rods removed at subsequent surgery.^3,19-21 Reported fusion rates varied from 86 to 100%.

In 42 patients with PEEK rod fusions who were followed for a mean of 31.4 months, 5 patients required adjacent segment surgery and 3 patients were treated for interbody cage migration and nonunion.¹⁷ Radiographic fusion rate was 86%. These authors concluded that PEEK rod fusion results were similar to those of other constructs, but not better, or perhaps worse than, metal rods.

Other studies have reported better results with PEEK.^{11,18,19,22-24} Highsmith and colleagues reported on 3 successful example cases of the use of PEEK rods.¹¹ De Iure and colleagues reported on 30 cases up to 5 levels (mean, 2.9) using autograft bone, with a mean follow up of 18 months.²³ Results were reported as satisfactory. Three patients had radiographic nonunions, 1 of which required revision for asymptomatic screw loosening at the cranial end of the construct. Qi and colleagues, reported on 20 patients with PEEK rods compared to 21 patients with titanium alloy rods.²⁴ Both groups had similar clinical outcomes, structural parameters, and 100% fusion rates. Athanasakopoulos and colleagues reported on 52 patients with up to 3 level fusions followed for a mean of 3 years.²² There were significant improvements in PROs: at 1 year 96% had radiographic union. Two patients had screw breakage, 1 of whom required revision to a metal rod construct. Colangeli and colleagues reported on 12 patients treated with PEEK rods compared with 12 who were treated with a dynamic system.¹⁸ They reported significant improvements, no complications, and 100% fusion at 6 months. Huang and colleagues reported on 38 patients intended to undergo a nonfusion procedure with 2 years of follow up.¹⁹ They reported good outcomes and 1 case of screw loosening. As no fusion was intended, no fusion outcomes were reported. All these studies suggested that longer follow up and more patients would be needed to assess the role of PEEK rods in lumbar fusion.³

Our results show a radiographic fusion rate of 86.4% and a radiographic nonunion rate of 9.9% in patients followed for at least 12 months. There was no clinical need for revision fusion at the index level. In our retrospective review, patients had high levels of smoking, DM, depression, immunosuppression, and obesity, which may negatively influence radiographic fusion rates when compared with other studies with 100% reported fusion rates. There was no instance of construct breakage or screw breakout, indicating that PEEK rods may allow enough flexibility to avoid construct failure under stress as in a fall.

Patient Reported Outcomes

Recent large studies were reviewed to assess the pre- and postoperative patient PROs reported in comparison with our study population (Table 4). In the Swedish Spine Registry analysis of 765 patients with 3 different types of lumbar fusion, the mean preoperative ODI score was 37 and mean SF-36 physical component score (PCS) was 35 for the most similar approach (posterolateral fusion with instrumentation).²⁵ At 1 year postoperation, the mean ODI was 26 and mean SF-36 PCS was 43. In the Spine Patient Outcomes Research Trial (SPORT) spondylolisthesis trial of 3 fusion types, the mean preoperative ODI was 41.2 and mean SF-36 PF score was 31.2 for the most similar approach (posterolateral instrumented fusion with pedicle screws).²⁶ Postoperative ODI scores at 1 year decreased by a mean 20.9 points and mean SF-36 PF scores increased by 29.9.

We report a mean preoperative SF-36 PF score of 28.9, which is lower than the SPORT study score for posterolateral fusion with instrumentation and the Swedish Study score for posterolateral instrumented fusion with pedicle screws. Similarly, our mean ODI score of 24.8 was better than the scores reported in the Swedish and SPORT studies. Our mean SF-36 PF score at 1 year postoperation was 59.3, compared with 58.5 for the SPORT study group and 46.0 in the Swedish study group. Mean ODI score at 1 year postoperatively was 14.5, which is better than the scores reported in the Swedish and SPORT studies.

Minimally clinically important difference (MCID) is a parameter used to gauge the efficacy of spine surgery. The utility of the MCID based upon PROs has been questioned in lumbar fusion surgery, as it has been thought to measure if the patient is “feeling” rather than “doing” better, the latter of which can be better measured by functional performance measures and objective, external socioeconomic anchors such as return to work and health care costs.²⁷ Nevertheless, validated PROs are reported widely in the spine surgery literature. The MCID in the SF-36 is not well established and can depend upon whether the scores are at the extremes or more in the central range and whether there is large variability in the scores.²⁸ Rheumatoid arthritis was estimated to be 7.1 points on the PF scale and 7.2 on the physical component summary (PCS).²⁹ For total knee replacement, it has been estimated to be 10 points on the SF-36 PCS.³⁰ Lumbar surgery was estimated to be 4.9 points for the SF-36 PCS and 12.8 points for the ODI.³¹ And the SPORT trial it has been estimated that a 30% change in the possible gain (or loss) may be an appropriate criterion.²⁸

With a preoperative mean SF-36 PF of 28.9, a 30% improvement in the available range (70.1) would be 21 points, making our data mean improvement of 30 points above the MCID. With a mean preoperative ODI of 24.6, a 30% improvement in the available range (25.4) would be 7.6 points, making our data mean improvement of 10.3 points better than the MCID. Therefore, our outcome results are comparable with other lumbar fusion outcome studies in terms of degree of disability prior to surgery and amount of improvement from surgery.

Adjacent Segment Disease

The precise factors resulting in adjacent segment disease are not fully defined.^3,32 In reviews of lumbar adjacent segment disease, reported rates ranged from 2.5% at 1 year up to 80 to 100% at 10 years, with lower rates with noninstrumented fusions.^4,32-34 Annual incidence of symptomatic adjacent segment disease following lumbar fusion ranges from 0.6 to 3.9% per year.^32,35,36 Mismatch between lumbar lordosis and pelvic incidence after fusion is thought to lead to higher rates of adjacent segment disease, as can a laminectomy at an adjacent segment.^32,36 Percutaneous fusion techniques or use of the Wiltse approach may lower the risk of adjacent segment disease due to avoidance of facet capsule disruption.^37,38

Dynamic stabilization techniques do not appear be clearly protective against adjacent segment disease, although biomechanical models suggest that they may do so.^33,39,40 A review by Wang and colleagues pooled studies to assess the risk of lumbar adjacent segment disease in spinal fusion to compare to disc arthroplasty and concluded that fusion carried a higher risk of adjacent segment disease.⁴¹ Definitive data on other types of motion preservation devices is lacking.³We show 3 adjacent segment fusions and 1 laminectomy have been needed in 108 patients and at a mean of 46 months after the index procedure and over 2.5 years of mean overall follow up. This is a low adjacent segment surgery rate compared to the historical data cited above, and may suggest some advantage for PEEK rods over more rigid constructs.

Strengths and Limitations

Strengths of this study include larger numbers than prior series of PEEK rod use and use in a population with high comorbidities linked to poor results without reduction in good outcomes. PEEK rods as used at the VAPHCS do not result in higher instrumentation costs than all metal constructs.

Study limitations include the retrospective nature with loss of follow up on some patients and incomplete radiographic and PROs in some patients. The use of 100% stereotactic guidance, the avoidance of interbody devices, and the off-label use of bone morphogenetic protein as part of the fusion construct introduce additional variables that may influence comparison to other studies. To avoid unnecessary radiation exposure, flexion extension films or CT scans were not routinely obtained if patients were doing well.⁴² Additionally, the degree of motion on dynamic views that would differentiate pseudarthrosis from arthrodesis has not been defined.⁵

Conclusions

The results presented show that lumbar fusion with PEEK rods can be undertaken with short hospitalization times and low complication rates, produce satisfactory clinical improvements, and result in radiographic fusion rates similar to metal constructs. Low rates of hardware failure or need for revision surgery were found. Preliminarily results of low rates of adjacent segment surgery are comparable with previously published metal construct rates. Longer follow up is needed to confirm these findings and to investigate whether semirigid constructs truly offer some protection from adjacent segment disease when compared to all metal constructs.

Acknowledgments
The authors thank Shirley McCartney, PhD, for editorial assistance.

Surgical treatment of degenerative lumbar spine disease has been rising steadily in the United States, and an increasing fraction of surgery involves lumbar fusion.^1,2 Various techniques are used to accomplish a lumbar fusion, including noninstrumented fusion, anterior lumbar interbody fusion (ALIF), lateral lumbar interbody fusion (XLIF, OLIF), posterior pedicle screw fusion, posterior cortical screw fusion, posterior interbody fusion (TLIF, PLIF), and interspinous process fusion. Rigid, metallic fusion hardware provides high stability and fusion rates, but it likely leads to stress shielding and adjacent segment disease.³ There is interest in less rigid and dynamic stabilization techniques to reduce the risk of adjacent segment disease, such as polyetheretherketone (PEEK) rods, which have been available since 2007. However, literature regarding PEEK rod utility is sparse and of mixed outcomes.^3,4 Additional patient reported outcome (PRO) information would be useful to both surgeons and patients. Using institutional data, this review was designed to examine our experience with PEEK rod lumbar fusion and to document PROs.

Methods

The study was approved by the institutional review board at the US Department of Veterans Affairs (VA) Portland Health Care System (VAPHCS) in Oregon with a waiver of authorization. In this retrospective, single center study, data were queried from the senior author’s (DAR) case logs from VA Computerized Patient Record System (CPRS). Electronic medical records, imaging, and PROs of all consecutive patients undergoing lumbar fusion at 1 or 2 levels with PEEK rods for degenerative disease were retrospectively reviewed. Cases of trauma, malignancy, or infection were excluded. From March 2011 through October 2019, 108 patients underwent lumbar fusion with PEEK rods.

Surgeries were conducted on a Mizuho OSI Jackson Table via bilateral 3 to 4 cm Wiltse incisions using the Medtronic Quadrant retractor system. Medtronic O-Arm images were acquired and delivered to a Medtronic Stealth Station for navigation of the screws. Monopolar coagulation was not used. PEEK pedicle screws were placed and verified with a second O-Arm spin before placing lordotic PEEK rods in the screw heads. No attempt was made to reduce any spondylolisthesis, but distraction was used to open the foramina and indirectly decompress the canal. An interbody device was placed only in treatment of multiply recurrent disc protrusion. After decortication of the transverse processes and facets, intertransverse fusion constructs consisting of calcium hydroxyapatite soaked in autologous bone marrow blood and wrapped in 6-mg bone morphogenetic protein-soaked sponges were placed on the bone. If canal decompression was indicated, a Medtronic Metrx retractor tube was then placed through one of the incisions and decompression carried out. Wounds were closed with absorbable suture. No bracing was used postoperatively. Figure 1 shows a typical single level PEEK rod fusion construct.

Statistical Analysis

Pre- and postoperative pairwise t tests were completed for patients with a complete data, using SAS 9.2 statistical package. Data are presented as standard deviation (SD) of the mean.

Results

Following application of the inclusion/exclusion criteria, 108 patients had undergone lumbar fusion with PEEK rods. Mean (SD) patient age was 60.2 (10.3) years and 88 patients were male (Table 1). Most surgeries were at L5-S1 and L4-5. There were 97 single-level fusions and 11 bilevel fusions. Seventy-four procedures were for spondylolisthesis, 23 for foraminal stenosis, 5 for degenerative disc disease, 3 for coronal imbalance with foraminal stenosis, 2 for pseudarthrosis after surgery elsewhere, and 1 for multiple recurrent disc herniation (Table 2). Twenty-five patients (23.1%) were current tobacco users and 28 (25.9%) were former smokers, 26 (24.1%) had diabetes mellitus (DM), 16 (14.8%) had low bone density by dual energy X-ray absorptiometry (DEXA) imaging, 35 (32.4%) had depression, and 7 (6.5%) were taking an immunosuppressive agent (chronic steroids, biological response modifiers, or methotrexate). Mean body mass index was 30.1.

Surgical Procedure

Of the 108 patients, the first 18 underwent a procedure with fluoroscopic guidance and the Medtronic FluoroNav and Stealth Systems. The next 90 patients underwent a procedure with O-Arm intraoperative CT scanning and Stealth frameless stereotactic navigation. The mean (SD) length of stay was 1.7 (1.3) days. There were no wound infections and no new neurologic deficits. Mean (SD) follow up time was 30.3 (21.8) months.

Imaging

Final imaging was by radiograph in 73 patients, CT in 31, and magnetic resonance imaging (MRI) in 3 (1 patient had no imaging). Sixty-seven patients (62.0%) had a bilateral arthrodesis, and 15 (13.9%) had at least a unilateral arthrodesis. MRI was not used to assess arthrodesis. Eight patients (7.4%) had no definite arthrodesis. Seventeen patients had inadequate or early imaging from which a fusion determination could not be made. Of 81 patients with > 11 months of follow up, 58 (71.6%) had a bilateral arthrodesis, 12 (14.8%) had a unilateral arthrodesis, 8 (9.9%) had no arthrodesis, and 3 (3.7%) were indeterminate.

No patient had any revision fusion surgery at the index level during follow up. Two patients had adjacent level fusions at 27 and 60 months after the index procedure. One patient had a laminectomy at an adjacent segment at 18 months postfusion, and 1 had a foraminotomy at an adjacent segment 89 months post fusion (Figure 3). Overall, there were 4 (3.7%) adjacent segment surgeries at a mean of 48.5 months after surgery. One patient had a sacro-iliac joint fusion below an L5-S1 fusion 17 months prior for persisting pain after the fusion procedure.

Patient Reported Outcomes

Preoperative SF-36 PF and ODI scores were available for 81 patients (Table 3). Postoperative SF-36 PF scores were obtained at 3 months for 65 of these patients, and at 1 year for 63 patients. Postoperative ODI scores were obtained at 3 months for 65 patients, and at 1 year for 55 patients. Among the 65 patients with completed SF-36 scores at 3 months, a mean increase of 22.4 (95% CI, 17-27; P < .001) was noted, and for the 63 patients at 1 year a mean increase of 30.3 (95% CI, 25-35; P < .001) was noted. Among the 65 patients with completed ODI scores at 3 months, a mean decrease of 6.8 (95% CI, 4.9-8.6; P < .001) was noted, and for the 55 patients with completed ODI scores at 1 year a mean decrease of 10.3 (n = 55; 95% CI, 8.4-12.2; P < .001) was noted.

Cost

We compared the hardware cost of a single level construct consisting of 4 pedicle screws, 4 locking caps, and 2 rods using a PEEK system with that of 2 other titanium construct systems. At VAPHCS, the PEEK system cost was about 71% of the cost of 2 other titanium construct systems and 62% of the cost when compared with Medtronic titanium rods.

Discussion

PEEK is useful for spine and cranial implants. It is inert and fully biocompatible with a modulus of elasticity between that of cortical and cancellous bone, and much lower than that of titanium, and is therefore considered to be semirigid.^3,4,6 PEEK rods are intermediate in stiffness between titanium rods (110 Gigapascals) and dynamic devices such as the Zimmer Biomet DYNESYS dynamic stabilization system or the Premia Spine TOPS system.³ Carbon fiber rods and carbon fiber reinforced PEEK implants are other semirigid rod alternatives.^7,8 PEEK rods for posterior lumbar fusion surgery were introduced in 2007. Li and colleagues provide a thorough review of the biomechanical properties of PEEK rods.³

PEEK is thought to have several advantages when compared with titanium. These advantages include more physiologic load sharing and reduction in stress shielding, improved durability, reduced risk of failure in osteoporotic bone, less wear debris, no change in bone forming environment, and imaging radiolucency.^4,9 Spinal PEEK cages have been reported to allow more uniform radiation dose distribution compared with metal constructs, an advantage that also may pertain to PEEK rods.¹⁰ Disadvantages of PEEK rods include an inability to detect rod breakage easily, lack of data on the use in more than minimally unstable clinical situations, and greater expense, although this was not the authors’ observation.^3,4,11

Importantly, it has been reported that PEEK rods permit a greater range of motion in all planes when compared with titanium rods.⁹ Polyetheretherketone rods unload the bone screw interface and increased the anterior column load to a more physiologic 75% when compared with titanium rods.^6,9 However, in another biomechanical study that compared titanium rods, PEEK rods, and a dynamic stabilization device, it was reported that anterior load sharing was 55%, 59%, and 75%, respectively.¹² This indicated that PEEK rods are closer to metal rods than truly dynamic devices for anterior load sharing. The endurance limit of a PEEK rod construct was similar to that of clinically useful metal systems.⁹ PEEK rods resulted in no increase in postfatigue motion compared with titanium rods in a biomechanical model.¹³ Intradiscal pressures at PEEK instrumented segments were similar to uninstrumented segments and greater than those with titanium rod constructs.¹⁴ Intradiscal pressures at adjacent segments were highest with dynamic devices, intermediate with semirigid rods, and lowest with rigid constructs; however, stress values at adjacent segments were lower in PEEK than titanium constructs in any direction of motion.^15,16

Fusion Rates

The use of PEEK rods in lumbar fusion has been reported previously.^3,4,17,18 However, these studies featured small sample sizes, short follow up times, and contradictory results.⁴ Of 8 outcome reports found in a systematic review, 2 studies reported on procedures designed to create nonfusion outcomes (a third similar trial from 2013 was not included in the systematic review), and 1 study reported only on the condition of PEEK rods removed at subsequent surgery.^3,19-21 Reported fusion rates varied from 86 to 100%.

In 42 patients with PEEK rod fusions who were followed for a mean of 31.4 months, 5 patients required adjacent segment surgery and 3 patients were treated for interbody cage migration and nonunion.¹⁷ Radiographic fusion rate was 86%. These authors concluded that PEEK rod fusion results were similar to those of other constructs, but not better, or perhaps worse than, metal rods.

Other studies have reported better results with PEEK.^{11,18,19,22-24} Highsmith and colleagues reported on 3 successful example cases of the use of PEEK rods.¹¹ De Iure and colleagues reported on 30 cases up to 5 levels (mean, 2.9) using autograft bone, with a mean follow up of 18 months.²³ Results were reported as satisfactory. Three patients had radiographic nonunions, 1 of which required revision for asymptomatic screw loosening at the cranial end of the construct. Qi and colleagues, reported on 20 patients with PEEK rods compared to 21 patients with titanium alloy rods.²⁴ Both groups had similar clinical outcomes, structural parameters, and 100% fusion rates. Athanasakopoulos and colleagues reported on 52 patients with up to 3 level fusions followed for a mean of 3 years.²² There were significant improvements in PROs: at 1 year 96% had radiographic union. Two patients had screw breakage, 1 of whom required revision to a metal rod construct. Colangeli and colleagues reported on 12 patients treated with PEEK rods compared with 12 who were treated with a dynamic system.¹⁸ They reported significant improvements, no complications, and 100% fusion at 6 months. Huang and colleagues reported on 38 patients intended to undergo a nonfusion procedure with 2 years of follow up.¹⁹ They reported good outcomes and 1 case of screw loosening. As no fusion was intended, no fusion outcomes were reported. All these studies suggested that longer follow up and more patients would be needed to assess the role of PEEK rods in lumbar fusion.³

Our results show a radiographic fusion rate of 86.4% and a radiographic nonunion rate of 9.9% in patients followed for at least 12 months. There was no clinical need for revision fusion at the index level. In our retrospective review, patients had high levels of smoking, DM, depression, immunosuppression, and obesity, which may negatively influence radiographic fusion rates when compared with other studies with 100% reported fusion rates. There was no instance of construct breakage or screw breakout, indicating that PEEK rods may allow enough flexibility to avoid construct failure under stress as in a fall.

Patient Reported Outcomes

Recent large studies were reviewed to assess the pre- and postoperative patient PROs reported in comparison with our study population (Table 4). In the Swedish Spine Registry analysis of 765 patients with 3 different types of lumbar fusion, the mean preoperative ODI score was 37 and mean SF-36 physical component score (PCS) was 35 for the most similar approach (posterolateral fusion with instrumentation).²⁵ At 1 year postoperation, the mean ODI was 26 and mean SF-36 PCS was 43. In the Spine Patient Outcomes Research Trial (SPORT) spondylolisthesis trial of 3 fusion types, the mean preoperative ODI was 41.2 and mean SF-36 PF score was 31.2 for the most similar approach (posterolateral instrumented fusion with pedicle screws).²⁶ Postoperative ODI scores at 1 year decreased by a mean 20.9 points and mean SF-36 PF scores increased by 29.9.

We report a mean preoperative SF-36 PF score of 28.9, which is lower than the SPORT study score for posterolateral fusion with instrumentation and the Swedish Study score for posterolateral instrumented fusion with pedicle screws. Similarly, our mean ODI score of 24.8 was better than the scores reported in the Swedish and SPORT studies. Our mean SF-36 PF score at 1 year postoperation was 59.3, compared with 58.5 for the SPORT study group and 46.0 in the Swedish study group. Mean ODI score at 1 year postoperatively was 14.5, which is better than the scores reported in the Swedish and SPORT studies.

Minimally clinically important difference (MCID) is a parameter used to gauge the efficacy of spine surgery. The utility of the MCID based upon PROs has been questioned in lumbar fusion surgery, as it has been thought to measure if the patient is “feeling” rather than “doing” better, the latter of which can be better measured by functional performance measures and objective, external socioeconomic anchors such as return to work and health care costs.²⁷ Nevertheless, validated PROs are reported widely in the spine surgery literature. The MCID in the SF-36 is not well established and can depend upon whether the scores are at the extremes or more in the central range and whether there is large variability in the scores.²⁸ Rheumatoid arthritis was estimated to be 7.1 points on the PF scale and 7.2 on the physical component summary (PCS).²⁹ For total knee replacement, it has been estimated to be 10 points on the SF-36 PCS.³⁰ Lumbar surgery was estimated to be 4.9 points for the SF-36 PCS and 12.8 points for the ODI.³¹ And the SPORT trial it has been estimated that a 30% change in the possible gain (or loss) may be an appropriate criterion.²⁸

With a preoperative mean SF-36 PF of 28.9, a 30% improvement in the available range (70.1) would be 21 points, making our data mean improvement of 30 points above the MCID. With a mean preoperative ODI of 24.6, a 30% improvement in the available range (25.4) would be 7.6 points, making our data mean improvement of 10.3 points better than the MCID. Therefore, our outcome results are comparable with other lumbar fusion outcome studies in terms of degree of disability prior to surgery and amount of improvement from surgery.

Adjacent Segment Disease

The precise factors resulting in adjacent segment disease are not fully defined.^3,32 In reviews of lumbar adjacent segment disease, reported rates ranged from 2.5% at 1 year up to 80 to 100% at 10 years, with lower rates with noninstrumented fusions.^4,32-34 Annual incidence of symptomatic adjacent segment disease following lumbar fusion ranges from 0.6 to 3.9% per year.^32,35,36 Mismatch between lumbar lordosis and pelvic incidence after fusion is thought to lead to higher rates of adjacent segment disease, as can a laminectomy at an adjacent segment.^32,36 Percutaneous fusion techniques or use of the Wiltse approach may lower the risk of adjacent segment disease due to avoidance of facet capsule disruption.^37,38

Dynamic stabilization techniques do not appear be clearly protective against adjacent segment disease, although biomechanical models suggest that they may do so.^33,39,40 A review by Wang and colleagues pooled studies to assess the risk of lumbar adjacent segment disease in spinal fusion to compare to disc arthroplasty and concluded that fusion carried a higher risk of adjacent segment disease.⁴¹ Definitive data on other types of motion preservation devices is lacking.³We show 3 adjacent segment fusions and 1 laminectomy have been needed in 108 patients and at a mean of 46 months after the index procedure and over 2.5 years of mean overall follow up. This is a low adjacent segment surgery rate compared to the historical data cited above, and may suggest some advantage for PEEK rods over more rigid constructs.

Strengths and Limitations

Strengths of this study include larger numbers than prior series of PEEK rod use and use in a population with high comorbidities linked to poor results without reduction in good outcomes. PEEK rods as used at the VAPHCS do not result in higher instrumentation costs than all metal constructs.

Study limitations include the retrospective nature with loss of follow up on some patients and incomplete radiographic and PROs in some patients. The use of 100% stereotactic guidance, the avoidance of interbody devices, and the off-label use of bone morphogenetic protein as part of the fusion construct introduce additional variables that may influence comparison to other studies. To avoid unnecessary radiation exposure, flexion extension films or CT scans were not routinely obtained if patients were doing well.⁴² Additionally, the degree of motion on dynamic views that would differentiate pseudarthrosis from arthrodesis has not been defined.⁵

Conclusions

The results presented show that lumbar fusion with PEEK rods can be undertaken with short hospitalization times and low complication rates, produce satisfactory clinical improvements, and result in radiographic fusion rates similar to metal constructs. Low rates of hardware failure or need for revision surgery were found. Preliminarily results of low rates of adjacent segment surgery are comparable with previously published metal construct rates. Longer follow up is needed to confirm these findings and to investigate whether semirigid constructs truly offer some protection from adjacent segment disease when compared to all metal constructs.

Acknowledgments
The authors thank Shirley McCartney, PhD, for editorial assistance.

Surgical treatment of degenerative lumbar spine disease has been rising steadily in the United States, and an increasing fraction of surgery involves lumbar fusion.^1,2 Various techniques are used to accomplish a lumbar fusion, including noninstrumented fusion, anterior lumbar interbody fusion (ALIF), lateral lumbar interbody fusion (XLIF, OLIF), posterior pedicle screw fusion, posterior cortical screw fusion, posterior interbody fusion (TLIF, PLIF), and interspinous process fusion. Rigid, metallic fusion hardware provides high stability and fusion rates, but it likely leads to stress shielding and adjacent segment disease.³ There is interest in less rigid and dynamic stabilization techniques to reduce the risk of adjacent segment disease, such as polyetheretherketone (PEEK) rods, which have been available since 2007. However, literature regarding PEEK rod utility is sparse and of mixed outcomes.^3,4 Additional patient reported outcome (PRO) information would be useful to both surgeons and patients. Using institutional data, this review was designed to examine our experience with PEEK rod lumbar fusion and to document PROs.

Methods

The study was approved by the institutional review board at the US Department of Veterans Affairs (VA) Portland Health Care System (VAPHCS) in Oregon with a waiver of authorization. In this retrospective, single center study, data were queried from the senior author’s (DAR) case logs from VA Computerized Patient Record System (CPRS). Electronic medical records, imaging, and PROs of all consecutive patients undergoing lumbar fusion at 1 or 2 levels with PEEK rods for degenerative disease were retrospectively reviewed. Cases of trauma, malignancy, or infection were excluded. From March 2011 through October 2019, 108 patients underwent lumbar fusion with PEEK rods.

Surgeries were conducted on a Mizuho OSI Jackson Table via bilateral 3 to 4 cm Wiltse incisions using the Medtronic Quadrant retractor system. Medtronic O-Arm images were acquired and delivered to a Medtronic Stealth Station for navigation of the screws. Monopolar coagulation was not used. PEEK pedicle screws were placed and verified with a second O-Arm spin before placing lordotic PEEK rods in the screw heads. No attempt was made to reduce any spondylolisthesis, but distraction was used to open the foramina and indirectly decompress the canal. An interbody device was placed only in treatment of multiply recurrent disc protrusion. After decortication of the transverse processes and facets, intertransverse fusion constructs consisting of calcium hydroxyapatite soaked in autologous bone marrow blood and wrapped in 6-mg bone morphogenetic protein-soaked sponges were placed on the bone. If canal decompression was indicated, a Medtronic Metrx retractor tube was then placed through one of the incisions and decompression carried out. Wounds were closed with absorbable suture. No bracing was used postoperatively. Figure 1 shows a typical single level PEEK rod fusion construct.

Statistical Analysis

Pre- and postoperative pairwise t tests were completed for patients with a complete data, using SAS 9.2 statistical package. Data are presented as standard deviation (SD) of the mean.

Results

Following application of the inclusion/exclusion criteria, 108 patients had undergone lumbar fusion with PEEK rods. Mean (SD) patient age was 60.2 (10.3) years and 88 patients were male (Table 1). Most surgeries were at L5-S1 and L4-5. There were 97 single-level fusions and 11 bilevel fusions. Seventy-four procedures were for spondylolisthesis, 23 for foraminal stenosis, 5 for degenerative disc disease, 3 for coronal imbalance with foraminal stenosis, 2 for pseudarthrosis after surgery elsewhere, and 1 for multiple recurrent disc herniation (Table 2). Twenty-five patients (23.1%) were current tobacco users and 28 (25.9%) were former smokers, 26 (24.1%) had diabetes mellitus (DM), 16 (14.8%) had low bone density by dual energy X-ray absorptiometry (DEXA) imaging, 35 (32.4%) had depression, and 7 (6.5%) were taking an immunosuppressive agent (chronic steroids, biological response modifiers, or methotrexate). Mean body mass index was 30.1.

Surgical Procedure

Of the 108 patients, the first 18 underwent a procedure with fluoroscopic guidance and the Medtronic FluoroNav and Stealth Systems. The next 90 patients underwent a procedure with O-Arm intraoperative CT scanning and Stealth frameless stereotactic navigation. The mean (SD) length of stay was 1.7 (1.3) days. There were no wound infections and no new neurologic deficits. Mean (SD) follow up time was 30.3 (21.8) months.

Imaging

Final imaging was by radiograph in 73 patients, CT in 31, and magnetic resonance imaging (MRI) in 3 (1 patient had no imaging). Sixty-seven patients (62.0%) had a bilateral arthrodesis, and 15 (13.9%) had at least a unilateral arthrodesis. MRI was not used to assess arthrodesis. Eight patients (7.4%) had no definite arthrodesis. Seventeen patients had inadequate or early imaging from which a fusion determination could not be made. Of 81 patients with > 11 months of follow up, 58 (71.6%) had a bilateral arthrodesis, 12 (14.8%) had a unilateral arthrodesis, 8 (9.9%) had no arthrodesis, and 3 (3.7%) were indeterminate.

No patient had any revision fusion surgery at the index level during follow up. Two patients had adjacent level fusions at 27 and 60 months after the index procedure. One patient had a laminectomy at an adjacent segment at 18 months postfusion, and 1 had a foraminotomy at an adjacent segment 89 months post fusion (Figure 3). Overall, there were 4 (3.7%) adjacent segment surgeries at a mean of 48.5 months after surgery. One patient had a sacro-iliac joint fusion below an L5-S1 fusion 17 months prior for persisting pain after the fusion procedure.

Patient Reported Outcomes

Preoperative SF-36 PF and ODI scores were available for 81 patients (Table 3). Postoperative SF-36 PF scores were obtained at 3 months for 65 of these patients, and at 1 year for 63 patients. Postoperative ODI scores were obtained at 3 months for 65 patients, and at 1 year for 55 patients. Among the 65 patients with completed SF-36 scores at 3 months, a mean increase of 22.4 (95% CI, 17-27; P < .001) was noted, and for the 63 patients at 1 year a mean increase of 30.3 (95% CI, 25-35; P < .001) was noted. Among the 65 patients with completed ODI scores at 3 months, a mean decrease of 6.8 (95% CI, 4.9-8.6; P < .001) was noted, and for the 55 patients with completed ODI scores at 1 year a mean decrease of 10.3 (n = 55; 95% CI, 8.4-12.2; P < .001) was noted.

Cost

We compared the hardware cost of a single level construct consisting of 4 pedicle screws, 4 locking caps, and 2 rods using a PEEK system with that of 2 other titanium construct systems. At VAPHCS, the PEEK system cost was about 71% of the cost of 2 other titanium construct systems and 62% of the cost when compared with Medtronic titanium rods.

Discussion

PEEK is useful for spine and cranial implants. It is inert and fully biocompatible with a modulus of elasticity between that of cortical and cancellous bone, and much lower than that of titanium, and is therefore considered to be semirigid.^3,4,6 PEEK rods are intermediate in stiffness between titanium rods (110 Gigapascals) and dynamic devices such as the Zimmer Biomet DYNESYS dynamic stabilization system or the Premia Spine TOPS system.³ Carbon fiber rods and carbon fiber reinforced PEEK implants are other semirigid rod alternatives.^7,8 PEEK rods for posterior lumbar fusion surgery were introduced in 2007. Li and colleagues provide a thorough review of the biomechanical properties of PEEK rods.³

PEEK is thought to have several advantages when compared with titanium. These advantages include more physiologic load sharing and reduction in stress shielding, improved durability, reduced risk of failure in osteoporotic bone, less wear debris, no change in bone forming environment, and imaging radiolucency.^4,9 Spinal PEEK cages have been reported to allow more uniform radiation dose distribution compared with metal constructs, an advantage that also may pertain to PEEK rods.¹⁰ Disadvantages of PEEK rods include an inability to detect rod breakage easily, lack of data on the use in more than minimally unstable clinical situations, and greater expense, although this was not the authors’ observation.^3,4,11

Importantly, it has been reported that PEEK rods permit a greater range of motion in all planes when compared with titanium rods.⁹ Polyetheretherketone rods unload the bone screw interface and increased the anterior column load to a more physiologic 75% when compared with titanium rods.^6,9 However, in another biomechanical study that compared titanium rods, PEEK rods, and a dynamic stabilization device, it was reported that anterior load sharing was 55%, 59%, and 75%, respectively.¹² This indicated that PEEK rods are closer to metal rods than truly dynamic devices for anterior load sharing. The endurance limit of a PEEK rod construct was similar to that of clinically useful metal systems.⁹ PEEK rods resulted in no increase in postfatigue motion compared with titanium rods in a biomechanical model.¹³ Intradiscal pressures at PEEK instrumented segments were similar to uninstrumented segments and greater than those with titanium rod constructs.¹⁴ Intradiscal pressures at adjacent segments were highest with dynamic devices, intermediate with semirigid rods, and lowest with rigid constructs; however, stress values at adjacent segments were lower in PEEK than titanium constructs in any direction of motion.^15,16

Fusion Rates

The use of PEEK rods in lumbar fusion has been reported previously.^3,4,17,18 However, these studies featured small sample sizes, short follow up times, and contradictory results.⁴ Of 8 outcome reports found in a systematic review, 2 studies reported on procedures designed to create nonfusion outcomes (a third similar trial from 2013 was not included in the systematic review), and 1 study reported only on the condition of PEEK rods removed at subsequent surgery.^3,19-21 Reported fusion rates varied from 86 to 100%.

In 42 patients with PEEK rod fusions who were followed for a mean of 31.4 months, 5 patients required adjacent segment surgery and 3 patients were treated for interbody cage migration and nonunion.¹⁷ Radiographic fusion rate was 86%. These authors concluded that PEEK rod fusion results were similar to those of other constructs, but not better, or perhaps worse than, metal rods.

Other studies have reported better results with PEEK.^{11,18,19,22-24} Highsmith and colleagues reported on 3 successful example cases of the use of PEEK rods.¹¹ De Iure and colleagues reported on 30 cases up to 5 levels (mean, 2.9) using autograft bone, with a mean follow up of 18 months.²³ Results were reported as satisfactory. Three patients had radiographic nonunions, 1 of which required revision for asymptomatic screw loosening at the cranial end of the construct. Qi and colleagues, reported on 20 patients with PEEK rods compared to 21 patients with titanium alloy rods.²⁴ Both groups had similar clinical outcomes, structural parameters, and 100% fusion rates. Athanasakopoulos and colleagues reported on 52 patients with up to 3 level fusions followed for a mean of 3 years.²² There were significant improvements in PROs: at 1 year 96% had radiographic union. Two patients had screw breakage, 1 of whom required revision to a metal rod construct. Colangeli and colleagues reported on 12 patients treated with PEEK rods compared with 12 who were treated with a dynamic system.¹⁸ They reported significant improvements, no complications, and 100% fusion at 6 months. Huang and colleagues reported on 38 patients intended to undergo a nonfusion procedure with 2 years of follow up.¹⁹ They reported good outcomes and 1 case of screw loosening. As no fusion was intended, no fusion outcomes were reported. All these studies suggested that longer follow up and more patients would be needed to assess the role of PEEK rods in lumbar fusion.³

Our results show a radiographic fusion rate of 86.4% and a radiographic nonunion rate of 9.9% in patients followed for at least 12 months. There was no clinical need for revision fusion at the index level. In our retrospective review, patients had high levels of smoking, DM, depression, immunosuppression, and obesity, which may negatively influence radiographic fusion rates when compared with other studies with 100% reported fusion rates. There was no instance of construct breakage or screw breakout, indicating that PEEK rods may allow enough flexibility to avoid construct failure under stress as in a fall.

Patient Reported Outcomes

Recent large studies were reviewed to assess the pre- and postoperative patient PROs reported in comparison with our study population (Table 4). In the Swedish Spine Registry analysis of 765 patients with 3 different types of lumbar fusion, the mean preoperative ODI score was 37 and mean SF-36 physical component score (PCS) was 35 for the most similar approach (posterolateral fusion with instrumentation).²⁵ At 1 year postoperation, the mean ODI was 26 and mean SF-36 PCS was 43. In the Spine Patient Outcomes Research Trial (SPORT) spondylolisthesis trial of 3 fusion types, the mean preoperative ODI was 41.2 and mean SF-36 PF score was 31.2 for the most similar approach (posterolateral instrumented fusion with pedicle screws).²⁶ Postoperative ODI scores at 1 year decreased by a mean 20.9 points and mean SF-36 PF scores increased by 29.9.

We report a mean preoperative SF-36 PF score of 28.9, which is lower than the SPORT study score for posterolateral fusion with instrumentation and the Swedish Study score for posterolateral instrumented fusion with pedicle screws. Similarly, our mean ODI score of 24.8 was better than the scores reported in the Swedish and SPORT studies. Our mean SF-36 PF score at 1 year postoperation was 59.3, compared with 58.5 for the SPORT study group and 46.0 in the Swedish study group. Mean ODI score at 1 year postoperatively was 14.5, which is better than the scores reported in the Swedish and SPORT studies.

Minimally clinically important difference (MCID) is a parameter used to gauge the efficacy of spine surgery. The utility of the MCID based upon PROs has been questioned in lumbar fusion surgery, as it has been thought to measure if the patient is “feeling” rather than “doing” better, the latter of which can be better measured by functional performance measures and objective, external socioeconomic anchors such as return to work and health care costs.²⁷ Nevertheless, validated PROs are reported widely in the spine surgery literature. The MCID in the SF-36 is not well established and can depend upon whether the scores are at the extremes or more in the central range and whether there is large variability in the scores.²⁸ Rheumatoid arthritis was estimated to be 7.1 points on the PF scale and 7.2 on the physical component summary (PCS).²⁹ For total knee replacement, it has been estimated to be 10 points on the SF-36 PCS.³⁰ Lumbar surgery was estimated to be 4.9 points for the SF-36 PCS and 12.8 points for the ODI.³¹ And the SPORT trial it has been estimated that a 30% change in the possible gain (or loss) may be an appropriate criterion.²⁸

With a preoperative mean SF-36 PF of 28.9, a 30% improvement in the available range (70.1) would be 21 points, making our data mean improvement of 30 points above the MCID. With a mean preoperative ODI of 24.6, a 30% improvement in the available range (25.4) would be 7.6 points, making our data mean improvement of 10.3 points better than the MCID. Therefore, our outcome results are comparable with other lumbar fusion outcome studies in terms of degree of disability prior to surgery and amount of improvement from surgery.

Adjacent Segment Disease

The precise factors resulting in adjacent segment disease are not fully defined.^3,32 In reviews of lumbar adjacent segment disease, reported rates ranged from 2.5% at 1 year up to 80 to 100% at 10 years, with lower rates with noninstrumented fusions.^4,32-34 Annual incidence of symptomatic adjacent segment disease following lumbar fusion ranges from 0.6 to 3.9% per year.^32,35,36 Mismatch between lumbar lordosis and pelvic incidence after fusion is thought to lead to higher rates of adjacent segment disease, as can a laminectomy at an adjacent segment.^32,36 Percutaneous fusion techniques or use of the Wiltse approach may lower the risk of adjacent segment disease due to avoidance of facet capsule disruption.^37,38

Dynamic stabilization techniques do not appear be clearly protective against adjacent segment disease, although biomechanical models suggest that they may do so.^33,39,40 A review by Wang and colleagues pooled studies to assess the risk of lumbar adjacent segment disease in spinal fusion to compare to disc arthroplasty and concluded that fusion carried a higher risk of adjacent segment disease.⁴¹ Definitive data on other types of motion preservation devices is lacking.³We show 3 adjacent segment fusions and 1 laminectomy have been needed in 108 patients and at a mean of 46 months after the index procedure and over 2.5 years of mean overall follow up. This is a low adjacent segment surgery rate compared to the historical data cited above, and may suggest some advantage for PEEK rods over more rigid constructs.

Strengths and Limitations

Strengths of this study include larger numbers than prior series of PEEK rod use and use in a population with high comorbidities linked to poor results without reduction in good outcomes. PEEK rods as used at the VAPHCS do not result in higher instrumentation costs than all metal constructs.

Study limitations include the retrospective nature with loss of follow up on some patients and incomplete radiographic and PROs in some patients. The use of 100% stereotactic guidance, the avoidance of interbody devices, and the off-label use of bone morphogenetic protein as part of the fusion construct introduce additional variables that may influence comparison to other studies. To avoid unnecessary radiation exposure, flexion extension films or CT scans were not routinely obtained if patients were doing well.⁴² Additionally, the degree of motion on dynamic views that would differentiate pseudarthrosis from arthrodesis has not been defined.⁵

Conclusions

The results presented show that lumbar fusion with PEEK rods can be undertaken with short hospitalization times and low complication rates, produce satisfactory clinical improvements, and result in radiographic fusion rates similar to metal constructs. Low rates of hardware failure or need for revision surgery were found. Preliminarily results of low rates of adjacent segment surgery are comparable with previously published metal construct rates. Longer follow up is needed to confirm these findings and to investigate whether semirigid constructs truly offer some protection from adjacent segment disease when compared to all metal constructs.

Acknowledgments
The authors thank Shirley McCartney, PhD, for editorial assistance.

The Veterans Health Administration (VHA), 1 of 3 administrative branches in the US Department of Veterans Affairs (VA), is the largest integrated health care system in the United States.¹ The VHA has 4 missions: providing health care to eligible veterans; supporting research to benefit veterans and the larger society; providing education for health care trainees; and supporting emergency response.¹ In service of these goals, VA has academic affiliations with universities throughout the country, offering unique, extensive training and research opportunities. Both the VA and the affiliate benefit from these partnerships. For example, VA affiliations with University of California (UC) medical schools benefit veteran care while facilitating the UC academic mission. Through these affiliations, trainees who learn within the VHA’s highly effective integrated care model become health care professionals (HCPs) who are prepared to enter health care systems in California and meet the state’s demand for high-quality integrated care with an emphasis on primary care, mental health care, and care for aging populations.^2,3

This report explores the history of the VHA, current veteran demographics and needs, VA academic affiliations, and the integrated care model of training in all VHA facilities. The VA and UC academic affiliation is described further with regard to shared research and educational functions. Finally, we identify potential risks to academic affiliations associated with increased VA reliance on community-based care following the implementation of recent legislation. We provide suggestions for VA academic affiliates to help assess and guide the potential impact of increased VA-managed community care.

VHA Resources

The VHA serves more than 9 million veterans through 170 medical centers and 1,074 outpatient care sites.¹ In fiscal year 2017, the VA provided 109 million outpatient visits, and treated 615,000 inpatient medicine/surgical patients and 149,000 patients in inpatient mental health.⁴ The VHA focuses on the distinct concerns of veterans, which arise from military service as well as their broader health care needs. Veterans have higher rates of medical and mental health conditions than those of the general public; different cohorts in this population experience distinct medical and mental health concerns (Table 1).⁵

In addition, although veterans are disproportionately older men, the population is diversifying.⁶ For example, the number of female veterans is growing; furthermore, changes in the law now allow lesbian, gay, bisexual, and transgender (LGBT) individuals to serve openly, which has both reduced barriers for this population and allowed for LGBT veterans who were not eligible for VA care due to less than honorable discharges to have those discharges upgraded. As a result, care has been tailored to include the development of Women Veterans Program Managers and related services and LGBT and related identities resources such as LGBT Veteran Care Coordinators in every VA facility nationwide.^7,8 The VA continues to adapt to serve all veterans; part of this adaptation is training HCPs to provide veteran-centered care for a growing and diversifying population.

VHA Resources in California

California has the largest population of veterans in the United States (Table 2).^9,10 Of the 9,116,200 VA enrollees nationwide, 760,910 (8%) reside in California, and of those, 463,410 had at least 1 VA visit in the past year.^3,10 The VHA is organized into 21 Veterans Integrated Service Networks (VISNs) that include multiple health care systems in the region associated with each VISN. California is part of VISN 21 (Northern California, Nevada, and Pacific Islands) and VISN 22 (Southern California, Nevada, and New Mexico). Among veterans who served in the recent Iraq and Afghanistan conflicts, 5.5% accessed care in VISN 21 and 9.3% accessed care in VISN 22.¹¹ The VHA provides critical infrastructure for meeting complex veteran needs, as well as related specialized training, education, and research for HCPs. This specialization has been the basis for the broad system of affiliations between VA and academic systems.

The VA continues to be a high priority in the federal budget process.¹² In 2017, slightly more than 9% of the VA health care budget, $6.4 billion, was spent on medical care in California.¹⁰ Consequently, California has a noteworthy portion of VA infrastructure (Table 3).^13,14 California has 8 VA medical centers (VAMCs) with hospital service (Fresno, Loma Linda, Long Beach, Palo Alto, Sacramento, San Diego, San Francisco, West Los Angeles), 3 VAMCs without hospital service (2 locations in the Palo Alto system and Sepulveda), 1 stand-alone extended-care facility (Martinez Community Living Center), and 1 stand-alone residential care facility (San Diego Domiciliary).⁹ The vast VA infrastructure in California and large population of veterans creates a strong demand for HCPs in the state.

VA Education and Collaboration

VA has been training clinicians and scholars since 1946, when VA academic affiliations were established by Memorandum Number 2.^15,16 Today, the VA is the largest educator of HCPs in the United States.¹⁷ In 2015, an estimated $10.3 to $12.5 billion was spent on mandatory Medicare graduate medical education (GME).¹⁸ In 2017, the VA spent $1.78 billion of discretionary funding on GME to fund 11,000 full-time equivalent (FTE) slots, leading to > 43,000 physician residents (> 30% of all physician residents) spending part of their training in a VHA facility.^18,19

This training mission has multiple benefits. It provides the VA with access to new HCPs who have the necessary training in veteran-specific needs, while supporting the national need for HCPs. In 2018, 120,890 clinical trainees received some or all of their training in the VA system.²⁰ Of the 152 US medical schools that are accredited by the Liaison Committee on Medical Education, 95% collaborate with the VA for training while 100% of the 34 doctor of osteopathic medicine programs have VA training collaborations.²⁰ The VA currently has an additional 18 partnerships with nursing schools.²¹ Further, 1,800 college and universities, including Hispanic-serving institutions and historically black colleges and universities, have VHA affiliations that provide training for more than 40 clinical health profession education programs.¹⁷

This training model has been successful in supporting VA staffing, as health care providers who trained in the VA are more likely to work in the VA.²² Among current VA employees, > 80% of optometrists, > 70% of podiatrists and psychologists, and > 60% of physicians received some part of their training in the VA system.²³ In combination with recent increased funding for staffing, the ability of the VA to directly hire trainees in identified professions, and the expansion of loan forgiveness to high-demand specialties (eg, psychiatry), the training partnership between the VA and affiliates has been critical in maintaining the needed VA workforce.^22,24,25

The VA Office of Academic Affiliations is responsible for all graduate medical and dental education administration in the VA system, which makes up 85% of its total budget. For each trainee, the VA provides approximately $60,000 toward their stipend in exchange for training and patient care time at a VHA hospital (Kenneth R. Jones, PhD, email communication, August 27, 2018).

California Health Care Education

The UC public university system, founded in 1869, currently has 10 campuses with a combined student body of > 280,000 students, along with 227,000 faculty and staff members.²⁶ For every research dollar provided by California, the UC secures $7 in federal and private funding.²⁶ The UC has 6 medical centers (Davis, Irvine, Los Angeles, Riverside, San Diego, and San Francisco); each is affiliated with at least 1 local VAMC.^27,28

California trains a substantial share of health care trainees. In 2016, there were 10,429 physician residents in training in California.²⁹ In 2017/2018, the San Francisco VAMC trained 1,178 medical students/residents, 57 pharmacy students, 25 nurse practitioner students, 19 optometry interns/students/residents, 11 dental students/residents, and 3 physical therapy students.²⁰ In total, 6,223 UC health professions students were trained in VHA facilities during the 2017/2018 training year (Table 4).²⁰ As of 2016, there were 105,907 physicians in California, and of those, 57% completed their GME in California.²⁹ In California in 2015, 74 GME-sponsoring institutions graduated 3,568 residents and fellows, an increase of 10% since 1997.³⁰ Of these sponsoring institutions, 6 of the top 8 programs were UC schools that graduated 48.4% (1,727) of all California residents and fellows in 2015.³⁰

VA Research Collaborations

The VA Office of Research and Development has existed for more than 90 years with a mission to improve veteran health and well-being via research and attract, train, and retain high-caliber researchers. VA provides a rich environment to conduct observational and interventional research due to its large, diverse veteran population, institutional support, and integrated information system with extensive EHR data.⁴¹ The success of the VA in facilitating research is evidenced by the fact that 3 VA investigators have been awarded Nobel prizes, and 7 have received Lasker Foundation Awards.⁴² The size of the VA allows for innovative large-scale research, such as the Million Veteran Program (MVP). The MVP study developed a mega-biobank of VA health records, questionnaires, and blood samples from nearly 1 million veterans to study genetic influences on health and disease and integrate genetic testing into health care delivery.⁴³ In addition to producing high-quality, innovative research, more than 60% of VA investigators also provide direct patient care.⁴²

VA research areas of focus include homelessness, polytrauma, traumatic brain injury, hearing and vision loss, spinal cord injury, mental health, pain management, precision medicine, prosthetics and amputation care, women’s health, and chronic diseases, such as Parkinson and Alzheimer diseases.⁴⁴ The VA estimates that, in 2021, total VA research spending will include a request of $787 million in addition to $370 million from the National Institutes of Health, the Department of Defense, and the Centers for Disease Control and Prevention, and $170 million from other nonfederal sources, for a projected total of $1.3 billion. This budget will support 2,200 projects with direct research and reimbursable employment of 3,275 FTEs,which are key to supporting VA academic affiliations.⁴⁵ These funds translate into substantial benefits to the UC system, including shared research and training resources, grant-funding opportunities for UC faculty, and the ability to recruit top researchers, educators, and clinicians to its institutions.

VA Reliance on Community Care 

The current VHA model is an integrated health care system that provides comprehensive, wraparound services to enrolled veterans, which are cost-effective, high quality, and consistently found to have equal or superior quality of care compared with that in the community.^6,46-50 Despite public criticism about wait times and access to care in the VA system, one study showed that VA wait-time statistics were comparable with or faster than those for community HCPs.^51,52 However, VA care coordination has undergone several changes to address these public criticisms, namely, the Veterans Access, Choice and Accountability Act of 2014 (38 USC § 1703 VACAA) and the VA MISSION Act of 2018 (42 USC § 274). VACAA was designed to increase access to care for veterans who live ≥ 40 miles from VA health care facilities or who are unable to been seen within 30 days of their preferred or clinically appropriate date.⁵³ More than 2 million veterans (almost 25% of VHA-enrolled veterans) have received community care since the inception of VACAA in 2014.⁵⁴

Recently, the MISSION Act mandated developing additional VA-coordinated community-based care through the establishment of a Veterans Community Care Program, which was established using existing VA 2019 fiscal year funds and did not include additional appropriations despite expanded criteria for community care referrals.⁵⁵ Without additional future appropriations, VA funds would be shifted from VA care into community care. While increasing access to community care has in some cases led to care that is faster and closer and that was previously inaccessible in local VA specialty care, these efforts could reduce veteran engagement with the VA system.⁵⁶

The changes implemented in VACAA and the VA MISSION Act were driven by important and valid concerns, including evidence of VA staff and officials covering up service deficiencies.⁵¹ Veterans in rural areas often have limited access to VA resources, and long travel to VAMCs or clinics can be an impediment. Veterans who have chosen community care tended to be those who have poorer health status, who live further away from VA facilities, women, and those who identified as White or Hispanic.^56,57 While VA health care is on average equivalent to or better than community resources, there is significant variability in quality within the VA system. Advocates have argued that providing competition and choice for veterans places pressure on the VA to improve care where it is not meeting expectations. Therefore, access to community care is an important resource for veterans and needs to be implemented effectively and efficiently to help veterans receive the care they need. However, expansion of community care access, depending on how it is implemented, also can have effects on academic partnerships and the education and research missions that should be incorporated into planning.

Each VA health care system receives funding through the Veterans Equitable Reimbursement Allocation (VERA), which provides funds largely based on the number of enrolled veterans and the complexity of the care they receive.⁵⁸ One potential implication of the shift among veterans to community care is a reduction in patients enrolled in VA programs, thus decreasing funding given to the VA to allocate for training and research. By definition, increased VA-managed community care means less opportunity for integrated training that brings together primary, mental health, and substance use care to meet patient needs. The Center for Medicare and Medicaid Services has developed a national initiative to help states develop programs in integrated care, particularly for individuals who are eligible for both Medicare and Medicaid.⁵⁹ For states to develop integrated care, they need trainees who function well in this model. Integrated care training is particularly vulnerable to disruption because any portion of a veteran’s care being transferred to the community can impede integration. In effect, training in integrated care, likely the most efficient and cost-effective approach to health care for reasons discussed earlier, could be reduced as providers and trainees are required to manage and coordinate patient care between separate institutions.³⁵

Educational Impact

The shift in usage from VA to community care has potential implications for academic affiliates, particularly in education and research.⁶⁰ If more people are served in community settings, potentially some VAMCs could be reduced, realigned, or closed. If this restructuring happens, academic partnerships could be impacted negatively. The VA is instituting an Infrastructure Review Commission with the task of examining current VA utilization. If a VA site with an academic affiliate was considered for realignment or closure, the reduction would eliminate the ability of the academic affiliate to provide education and research collaborations at that site.

In a less drastic manner, increasing care in the community may change opportunities for academic affiliates to partner with the VA. As noted, the UC system and California veterans benefit immensely from the VHA as an integrated health care system with dedicated missions of education and research. This partnership is a model in which the VA is the primary source of care for eligible enrolled veterans and provides integrated comprehensive services. If the VA moves to serving primarily as a coordinator of community HCPs rather than a direct provider of health care, academic affiliates would need to make major adjustments to both the education and training models. This change could particularly affect specialty training programs that rely on having adequate volumes of patients to provide an extensive experience to meet training needs. If fewer veterans receive care directly from the VA and are instead dispersed in the community, that will reduce the ability of academic faculty to participate in the education of medical and affiliated trainees and to participate in research in VA settings. It is unclear what other model could replace such a system and be as beneficial to the VA and the academic partners with which it is currently affiliated.

Given the needs that led to the VA increasing access to care and the potential implications discussed for the VA and partnerships with academic affiliates, VA health care systems and academic affiliate partners should consider several steps. These steps involve assessment, coordination, and promotion.

Both the VA and academic affiliates would benefit if the VA shared assessment data on the use of community care, particularly identifying changes that relate to key training and/or research missions. Such data sharing can be critical to determine whether any risks (or potential opportunities) need to be addressed. In addition, increasing research on the outcomes related to both VA care and community-based care is of high value to determine whether the current changes are achieving intended goals. The VA recently funded such work through its research service, and such work is critical for guiding future policy for the VA and for the affiliates.

Coordination among the VA, academic affiliates, and community partners is vital for change. The issue of community care expansion should be a standing item on coordination meetings and shared governance councils between the institutions. It may make sense to establish specific workgroups or committees to coordinate tracking and assessment of the effect of community care expansion on the shared academic mission. One way to address the potential effect of increased community care on the research and education missions would be to include community partners into the partnerships. This strategy could potentially take a number of different forms, from providing education and training to community HCPs, having VA trainees rotate to community settings, or inviting community settings to be research sites for clinical trials. Such partnerships could potentially improve patient care and support the other academic missions. Coordination could be meaningfully improved by having community HCPs access the VA EHR, thus easing communications. Funding is available for EHR access in the VA MISSION Act and should be a high priority as community care expands. The more that community partners can access and connect with the VA EHR the better they will be able to coordinate care.

Third, the VA and its academic partners need to promote and educate veterans, their families, and their advocates on the benefits that are available through VA care and that are enhanced through academic partnerships. While the VA has been the target of justified criticism, many of its strengths addressed here are not broadly recognized. The VA could promote its sharing of staff and resources with the top academic health care institutions in an area and that veterans often have access to resources that otherwise would not be available without the academic affiliate. Making sure veterans are aware of the benefits available can potentially mitigate the need for community care.

Conclusions

Given changes from VACAA and the VA MISSION Act, VA and academic affiliates should be active partners in planning for future health care by providing input and feedback on VA structure to help shape federal and state systems moving forward. Institutions can take steps to steer their futures and meet growing clinical, training, and research needs. The VA and its academic partners in health care research are well positioned to develop projects to assess the effects of these changes. Evaluation of key variables including patient care, education, and research productivity are warranted to guide policymakers as they assess whether these changes in the VA are achieving the expressed goals of improving veteran care. Other opportunities to collaborate in the wake of the MISSION Act remain to be discovered within each academic affiliation. By strengthening working relationships between VA and academic teams, these deeply important partnerships can continue to produce clinical, research, and education outcomes that meet the needs of our veterans, our federal and state health care systems, and our country.

Acknowledgments

Dr. Sells was supported by the Department of Veterans Affairs, Veterans Health Administration, Office of Academic Affiliations VA Quality Scholars Advanced Fellowship Program.

The Veterans Health Administration (VHA), 1 of 3 administrative branches in the US Department of Veterans Affairs (VA), is the largest integrated health care system in the United States.¹ The VHA has 4 missions: providing health care to eligible veterans; supporting research to benefit veterans and the larger society; providing education for health care trainees; and supporting emergency response.¹ In service of these goals, VA has academic affiliations with universities throughout the country, offering unique, extensive training and research opportunities. Both the VA and the affiliate benefit from these partnerships. For example, VA affiliations with University of California (UC) medical schools benefit veteran care while facilitating the UC academic mission. Through these affiliations, trainees who learn within the VHA’s highly effective integrated care model become health care professionals (HCPs) who are prepared to enter health care systems in California and meet the state’s demand for high-quality integrated care with an emphasis on primary care, mental health care, and care for aging populations.^2,3

This report explores the history of the VHA, current veteran demographics and needs, VA academic affiliations, and the integrated care model of training in all VHA facilities. The VA and UC academic affiliation is described further with regard to shared research and educational functions. Finally, we identify potential risks to academic affiliations associated with increased VA reliance on community-based care following the implementation of recent legislation. We provide suggestions for VA academic affiliates to help assess and guide the potential impact of increased VA-managed community care.

VHA Resources

The VHA serves more than 9 million veterans through 170 medical centers and 1,074 outpatient care sites.¹ In fiscal year 2017, the VA provided 109 million outpatient visits, and treated 615,000 inpatient medicine/surgical patients and 149,000 patients in inpatient mental health.⁴ The VHA focuses on the distinct concerns of veterans, which arise from military service as well as their broader health care needs. Veterans have higher rates of medical and mental health conditions than those of the general public; different cohorts in this population experience distinct medical and mental health concerns (Table 1).⁵

In addition, although veterans are disproportionately older men, the population is diversifying.⁶ For example, the number of female veterans is growing; furthermore, changes in the law now allow lesbian, gay, bisexual, and transgender (LGBT) individuals to serve openly, which has both reduced barriers for this population and allowed for LGBT veterans who were not eligible for VA care due to less than honorable discharges to have those discharges upgraded. As a result, care has been tailored to include the development of Women Veterans Program Managers and related services and LGBT and related identities resources such as LGBT Veteran Care Coordinators in every VA facility nationwide.^7,8 The VA continues to adapt to serve all veterans; part of this adaptation is training HCPs to provide veteran-centered care for a growing and diversifying population.

VHA Resources in California

California has the largest population of veterans in the United States (Table 2).^9,10 Of the 9,116,200 VA enrollees nationwide, 760,910 (8%) reside in California, and of those, 463,410 had at least 1 VA visit in the past year.^3,10 The VHA is organized into 21 Veterans Integrated Service Networks (VISNs) that include multiple health care systems in the region associated with each VISN. California is part of VISN 21 (Northern California, Nevada, and Pacific Islands) and VISN 22 (Southern California, Nevada, and New Mexico). Among veterans who served in the recent Iraq and Afghanistan conflicts, 5.5% accessed care in VISN 21 and 9.3% accessed care in VISN 22.¹¹ The VHA provides critical infrastructure for meeting complex veteran needs, as well as related specialized training, education, and research for HCPs. This specialization has been the basis for the broad system of affiliations between VA and academic systems.

The VA continues to be a high priority in the federal budget process.¹² In 2017, slightly more than 9% of the VA health care budget, $6.4 billion, was spent on medical care in California.¹⁰ Consequently, California has a noteworthy portion of VA infrastructure (Table 3).^13,14 California has 8 VA medical centers (VAMCs) with hospital service (Fresno, Loma Linda, Long Beach, Palo Alto, Sacramento, San Diego, San Francisco, West Los Angeles), 3 VAMCs without hospital service (2 locations in the Palo Alto system and Sepulveda), 1 stand-alone extended-care facility (Martinez Community Living Center), and 1 stand-alone residential care facility (San Diego Domiciliary).⁹ The vast VA infrastructure in California and large population of veterans creates a strong demand for HCPs in the state.

VA Education and Collaboration

VA has been training clinicians and scholars since 1946, when VA academic affiliations were established by Memorandum Number 2.^15,16 Today, the VA is the largest educator of HCPs in the United States.¹⁷ In 2015, an estimated $10.3 to $12.5 billion was spent on mandatory Medicare graduate medical education (GME).¹⁸ In 2017, the VA spent $1.78 billion of discretionary funding on GME to fund 11,000 full-time equivalent (FTE) slots, leading to > 43,000 physician residents (> 30% of all physician residents) spending part of their training in a VHA facility.^18,19

This training mission has multiple benefits. It provides the VA with access to new HCPs who have the necessary training in veteran-specific needs, while supporting the national need for HCPs. In 2018, 120,890 clinical trainees received some or all of their training in the VA system.²⁰ Of the 152 US medical schools that are accredited by the Liaison Committee on Medical Education, 95% collaborate with the VA for training while 100% of the 34 doctor of osteopathic medicine programs have VA training collaborations.²⁰ The VA currently has an additional 18 partnerships with nursing schools.²¹ Further, 1,800 college and universities, including Hispanic-serving institutions and historically black colleges and universities, have VHA affiliations that provide training for more than 40 clinical health profession education programs.¹⁷

This training model has been successful in supporting VA staffing, as health care providers who trained in the VA are more likely to work in the VA.²² Among current VA employees, > 80% of optometrists, > 70% of podiatrists and psychologists, and > 60% of physicians received some part of their training in the VA system.²³ In combination with recent increased funding for staffing, the ability of the VA to directly hire trainees in identified professions, and the expansion of loan forgiveness to high-demand specialties (eg, psychiatry), the training partnership between the VA and affiliates has been critical in maintaining the needed VA workforce.^22,24,25

The VA Office of Academic Affiliations is responsible for all graduate medical and dental education administration in the VA system, which makes up 85% of its total budget. For each trainee, the VA provides approximately $60,000 toward their stipend in exchange for training and patient care time at a VHA hospital (Kenneth R. Jones, PhD, email communication, August 27, 2018).

California Health Care Education

The UC public university system, founded in 1869, currently has 10 campuses with a combined student body of > 280,000 students, along with 227,000 faculty and staff members.²⁶ For every research dollar provided by California, the UC secures $7 in federal and private funding.²⁶ The UC has 6 medical centers (Davis, Irvine, Los Angeles, Riverside, San Diego, and San Francisco); each is affiliated with at least 1 local VAMC.^27,28

California trains a substantial share of health care trainees. In 2016, there were 10,429 physician residents in training in California.²⁹ In 2017/2018, the San Francisco VAMC trained 1,178 medical students/residents, 57 pharmacy students, 25 nurse practitioner students, 19 optometry interns/students/residents, 11 dental students/residents, and 3 physical therapy students.²⁰ In total, 6,223 UC health professions students were trained in VHA facilities during the 2017/2018 training year (Table 4).²⁰ As of 2016, there were 105,907 physicians in California, and of those, 57% completed their GME in California.²⁹ In California in 2015, 74 GME-sponsoring institutions graduated 3,568 residents and fellows, an increase of 10% since 1997.³⁰ Of these sponsoring institutions, 6 of the top 8 programs were UC schools that graduated 48.4% (1,727) of all California residents and fellows in 2015.³⁰

VA Research Collaborations

The VA Office of Research and Development has existed for more than 90 years with a mission to improve veteran health and well-being via research and attract, train, and retain high-caliber researchers. VA provides a rich environment to conduct observational and interventional research due to its large, diverse veteran population, institutional support, and integrated information system with extensive EHR data.⁴¹ The success of the VA in facilitating research is evidenced by the fact that 3 VA investigators have been awarded Nobel prizes, and 7 have received Lasker Foundation Awards.⁴² The size of the VA allows for innovative large-scale research, such as the Million Veteran Program (MVP). The MVP study developed a mega-biobank of VA health records, questionnaires, and blood samples from nearly 1 million veterans to study genetic influences on health and disease and integrate genetic testing into health care delivery.⁴³ In addition to producing high-quality, innovative research, more than 60% of VA investigators also provide direct patient care.⁴²

VA research areas of focus include homelessness, polytrauma, traumatic brain injury, hearing and vision loss, spinal cord injury, mental health, pain management, precision medicine, prosthetics and amputation care, women’s health, and chronic diseases, such as Parkinson and Alzheimer diseases.⁴⁴ The VA estimates that, in 2021, total VA research spending will include a request of $787 million in addition to $370 million from the National Institutes of Health, the Department of Defense, and the Centers for Disease Control and Prevention, and $170 million from other nonfederal sources, for a projected total of $1.3 billion. This budget will support 2,200 projects with direct research and reimbursable employment of 3,275 FTEs,which are key to supporting VA academic affiliations.⁴⁵ These funds translate into substantial benefits to the UC system, including shared research and training resources, grant-funding opportunities for UC faculty, and the ability to recruit top researchers, educators, and clinicians to its institutions.

VA Reliance on Community Care 

The current VHA model is an integrated health care system that provides comprehensive, wraparound services to enrolled veterans, which are cost-effective, high quality, and consistently found to have equal or superior quality of care compared with that in the community.^6,46-50 Despite public criticism about wait times and access to care in the VA system, one study showed that VA wait-time statistics were comparable with or faster than those for community HCPs.^51,52 However, VA care coordination has undergone several changes to address these public criticisms, namely, the Veterans Access, Choice and Accountability Act of 2014 (38 USC § 1703 VACAA) and the VA MISSION Act of 2018 (42 USC § 274). VACAA was designed to increase access to care for veterans who live ≥ 40 miles from VA health care facilities or who are unable to been seen within 30 days of their preferred or clinically appropriate date.⁵³ More than 2 million veterans (almost 25% of VHA-enrolled veterans) have received community care since the inception of VACAA in 2014.⁵⁴

Recently, the MISSION Act mandated developing additional VA-coordinated community-based care through the establishment of a Veterans Community Care Program, which was established using existing VA 2019 fiscal year funds and did not include additional appropriations despite expanded criteria for community care referrals.⁵⁵ Without additional future appropriations, VA funds would be shifted from VA care into community care. While increasing access to community care has in some cases led to care that is faster and closer and that was previously inaccessible in local VA specialty care, these efforts could reduce veteran engagement with the VA system.⁵⁶

The changes implemented in VACAA and the VA MISSION Act were driven by important and valid concerns, including evidence of VA staff and officials covering up service deficiencies.⁵¹ Veterans in rural areas often have limited access to VA resources, and long travel to VAMCs or clinics can be an impediment. Veterans who have chosen community care tended to be those who have poorer health status, who live further away from VA facilities, women, and those who identified as White or Hispanic.^56,57 While VA health care is on average equivalent to or better than community resources, there is significant variability in quality within the VA system. Advocates have argued that providing competition and choice for veterans places pressure on the VA to improve care where it is not meeting expectations. Therefore, access to community care is an important resource for veterans and needs to be implemented effectively and efficiently to help veterans receive the care they need. However, expansion of community care access, depending on how it is implemented, also can have effects on academic partnerships and the education and research missions that should be incorporated into planning.

Each VA health care system receives funding through the Veterans Equitable Reimbursement Allocation (VERA), which provides funds largely based on the number of enrolled veterans and the complexity of the care they receive.⁵⁸ One potential implication of the shift among veterans to community care is a reduction in patients enrolled in VA programs, thus decreasing funding given to the VA to allocate for training and research. By definition, increased VA-managed community care means less opportunity for integrated training that brings together primary, mental health, and substance use care to meet patient needs. The Center for Medicare and Medicaid Services has developed a national initiative to help states develop programs in integrated care, particularly for individuals who are eligible for both Medicare and Medicaid.⁵⁹ For states to develop integrated care, they need trainees who function well in this model. Integrated care training is particularly vulnerable to disruption because any portion of a veteran’s care being transferred to the community can impede integration. In effect, training in integrated care, likely the most efficient and cost-effective approach to health care for reasons discussed earlier, could be reduced as providers and trainees are required to manage and coordinate patient care between separate institutions.³⁵

Educational Impact

The shift in usage from VA to community care has potential implications for academic affiliates, particularly in education and research.⁶⁰ If more people are served in community settings, potentially some VAMCs could be reduced, realigned, or closed. If this restructuring happens, academic partnerships could be impacted negatively. The VA is instituting an Infrastructure Review Commission with the task of examining current VA utilization. If a VA site with an academic affiliate was considered for realignment or closure, the reduction would eliminate the ability of the academic affiliate to provide education and research collaborations at that site.

In a less drastic manner, increasing care in the community may change opportunities for academic affiliates to partner with the VA. As noted, the UC system and California veterans benefit immensely from the VHA as an integrated health care system with dedicated missions of education and research. This partnership is a model in which the VA is the primary source of care for eligible enrolled veterans and provides integrated comprehensive services. If the VA moves to serving primarily as a coordinator of community HCPs rather than a direct provider of health care, academic affiliates would need to make major adjustments to both the education and training models. This change could particularly affect specialty training programs that rely on having adequate volumes of patients to provide an extensive experience to meet training needs. If fewer veterans receive care directly from the VA and are instead dispersed in the community, that will reduce the ability of academic faculty to participate in the education of medical and affiliated trainees and to participate in research in VA settings. It is unclear what other model could replace such a system and be as beneficial to the VA and the academic partners with which it is currently affiliated.

Given the needs that led to the VA increasing access to care and the potential implications discussed for the VA and partnerships with academic affiliates, VA health care systems and academic affiliate partners should consider several steps. These steps involve assessment, coordination, and promotion.

Both the VA and academic affiliates would benefit if the VA shared assessment data on the use of community care, particularly identifying changes that relate to key training and/or research missions. Such data sharing can be critical to determine whether any risks (or potential opportunities) need to be addressed. In addition, increasing research on the outcomes related to both VA care and community-based care is of high value to determine whether the current changes are achieving intended goals. The VA recently funded such work through its research service, and such work is critical for guiding future policy for the VA and for the affiliates.

Coordination among the VA, academic affiliates, and community partners is vital for change. The issue of community care expansion should be a standing item on coordination meetings and shared governance councils between the institutions. It may make sense to establish specific workgroups or committees to coordinate tracking and assessment of the effect of community care expansion on the shared academic mission. One way to address the potential effect of increased community care on the research and education missions would be to include community partners into the partnerships. This strategy could potentially take a number of different forms, from providing education and training to community HCPs, having VA trainees rotate to community settings, or inviting community settings to be research sites for clinical trials. Such partnerships could potentially improve patient care and support the other academic missions. Coordination could be meaningfully improved by having community HCPs access the VA EHR, thus easing communications. Funding is available for EHR access in the VA MISSION Act and should be a high priority as community care expands. The more that community partners can access and connect with the VA EHR the better they will be able to coordinate care.

Third, the VA and its academic partners need to promote and educate veterans, their families, and their advocates on the benefits that are available through VA care and that are enhanced through academic partnerships. While the VA has been the target of justified criticism, many of its strengths addressed here are not broadly recognized. The VA could promote its sharing of staff and resources with the top academic health care institutions in an area and that veterans often have access to resources that otherwise would not be available without the academic affiliate. Making sure veterans are aware of the benefits available can potentially mitigate the need for community care.

Conclusions

Given changes from VACAA and the VA MISSION Act, VA and academic affiliates should be active partners in planning for future health care by providing input and feedback on VA structure to help shape federal and state systems moving forward. Institutions can take steps to steer their futures and meet growing clinical, training, and research needs. The VA and its academic partners in health care research are well positioned to develop projects to assess the effects of these changes. Evaluation of key variables including patient care, education, and research productivity are warranted to guide policymakers as they assess whether these changes in the VA are achieving the expressed goals of improving veteran care. Other opportunities to collaborate in the wake of the MISSION Act remain to be discovered within each academic affiliation. By strengthening working relationships between VA and academic teams, these deeply important partnerships can continue to produce clinical, research, and education outcomes that meet the needs of our veterans, our federal and state health care systems, and our country.

Acknowledgments

Dr. Sells was supported by the Department of Veterans Affairs, Veterans Health Administration, Office of Academic Affiliations VA Quality Scholars Advanced Fellowship Program.

The Veterans Health Administration (VHA), 1 of 3 administrative branches in the US Department of Veterans Affairs (VA), is the largest integrated health care system in the United States.¹ The VHA has 4 missions: providing health care to eligible veterans; supporting research to benefit veterans and the larger society; providing education for health care trainees; and supporting emergency response.¹ In service of these goals, VA has academic affiliations with universities throughout the country, offering unique, extensive training and research opportunities. Both the VA and the affiliate benefit from these partnerships. For example, VA affiliations with University of California (UC) medical schools benefit veteran care while facilitating the UC academic mission. Through these affiliations, trainees who learn within the VHA’s highly effective integrated care model become health care professionals (HCPs) who are prepared to enter health care systems in California and meet the state’s demand for high-quality integrated care with an emphasis on primary care, mental health care, and care for aging populations.^2,3

This report explores the history of the VHA, current veteran demographics and needs, VA academic affiliations, and the integrated care model of training in all VHA facilities. The VA and UC academic affiliation is described further with regard to shared research and educational functions. Finally, we identify potential risks to academic affiliations associated with increased VA reliance on community-based care following the implementation of recent legislation. We provide suggestions for VA academic affiliates to help assess and guide the potential impact of increased VA-managed community care.

VHA Resources

The VHA serves more than 9 million veterans through 170 medical centers and 1,074 outpatient care sites.¹ In fiscal year 2017, the VA provided 109 million outpatient visits, and treated 615,000 inpatient medicine/surgical patients and 149,000 patients in inpatient mental health.⁴ The VHA focuses on the distinct concerns of veterans, which arise from military service as well as their broader health care needs. Veterans have higher rates of medical and mental health conditions than those of the general public; different cohorts in this population experience distinct medical and mental health concerns (Table 1).⁵

In addition, although veterans are disproportionately older men, the population is diversifying.⁶ For example, the number of female veterans is growing; furthermore, changes in the law now allow lesbian, gay, bisexual, and transgender (LGBT) individuals to serve openly, which has both reduced barriers for this population and allowed for LGBT veterans who were not eligible for VA care due to less than honorable discharges to have those discharges upgraded. As a result, care has been tailored to include the development of Women Veterans Program Managers and related services and LGBT and related identities resources such as LGBT Veteran Care Coordinators in every VA facility nationwide.^7,8 The VA continues to adapt to serve all veterans; part of this adaptation is training HCPs to provide veteran-centered care for a growing and diversifying population.

VHA Resources in California

California has the largest population of veterans in the United States (Table 2).^9,10 Of the 9,116,200 VA enrollees nationwide, 760,910 (8%) reside in California, and of those, 463,410 had at least 1 VA visit in the past year.^3,10 The VHA is organized into 21 Veterans Integrated Service Networks (VISNs) that include multiple health care systems in the region associated with each VISN. California is part of VISN 21 (Northern California, Nevada, and Pacific Islands) and VISN 22 (Southern California, Nevada, and New Mexico). Among veterans who served in the recent Iraq and Afghanistan conflicts, 5.5% accessed care in VISN 21 and 9.3% accessed care in VISN 22.¹¹ The VHA provides critical infrastructure for meeting complex veteran needs, as well as related specialized training, education, and research for HCPs. This specialization has been the basis for the broad system of affiliations between VA and academic systems.

The VA continues to be a high priority in the federal budget process.¹² In 2017, slightly more than 9% of the VA health care budget, $6.4 billion, was spent on medical care in California.¹⁰ Consequently, California has a noteworthy portion of VA infrastructure (Table 3).^13,14 California has 8 VA medical centers (VAMCs) with hospital service (Fresno, Loma Linda, Long Beach, Palo Alto, Sacramento, San Diego, San Francisco, West Los Angeles), 3 VAMCs without hospital service (2 locations in the Palo Alto system and Sepulveda), 1 stand-alone extended-care facility (Martinez Community Living Center), and 1 stand-alone residential care facility (San Diego Domiciliary).⁹ The vast VA infrastructure in California and large population of veterans creates a strong demand for HCPs in the state.

VA Education and Collaboration

VA has been training clinicians and scholars since 1946, when VA academic affiliations were established by Memorandum Number 2.^15,16 Today, the VA is the largest educator of HCPs in the United States.¹⁷ In 2015, an estimated $10.3 to $12.5 billion was spent on mandatory Medicare graduate medical education (GME).¹⁸ In 2017, the VA spent $1.78 billion of discretionary funding on GME to fund 11,000 full-time equivalent (FTE) slots, leading to > 43,000 physician residents (> 30% of all physician residents) spending part of their training in a VHA facility.^18,19

This training mission has multiple benefits. It provides the VA with access to new HCPs who have the necessary training in veteran-specific needs, while supporting the national need for HCPs. In 2018, 120,890 clinical trainees received some or all of their training in the VA system.²⁰ Of the 152 US medical schools that are accredited by the Liaison Committee on Medical Education, 95% collaborate with the VA for training while 100% of the 34 doctor of osteopathic medicine programs have VA training collaborations.²⁰ The VA currently has an additional 18 partnerships with nursing schools.²¹ Further, 1,800 college and universities, including Hispanic-serving institutions and historically black colleges and universities, have VHA affiliations that provide training for more than 40 clinical health profession education programs.¹⁷

This training model has been successful in supporting VA staffing, as health care providers who trained in the VA are more likely to work in the VA.²² Among current VA employees, > 80% of optometrists, > 70% of podiatrists and psychologists, and > 60% of physicians received some part of their training in the VA system.²³ In combination with recent increased funding for staffing, the ability of the VA to directly hire trainees in identified professions, and the expansion of loan forgiveness to high-demand specialties (eg, psychiatry), the training partnership between the VA and affiliates has been critical in maintaining the needed VA workforce.^22,24,25

The VA Office of Academic Affiliations is responsible for all graduate medical and dental education administration in the VA system, which makes up 85% of its total budget. For each trainee, the VA provides approximately $60,000 toward their stipend in exchange for training and patient care time at a VHA hospital (Kenneth R. Jones, PhD, email communication, August 27, 2018).

California Health Care Education

The UC public university system, founded in 1869, currently has 10 campuses with a combined student body of > 280,000 students, along with 227,000 faculty and staff members.²⁶ For every research dollar provided by California, the UC secures $7 in federal and private funding.²⁶ The UC has 6 medical centers (Davis, Irvine, Los Angeles, Riverside, San Diego, and San Francisco); each is affiliated with at least 1 local VAMC.^27,28

California trains a substantial share of health care trainees. In 2016, there were 10,429 physician residents in training in California.²⁹ In 2017/2018, the San Francisco VAMC trained 1,178 medical students/residents, 57 pharmacy students, 25 nurse practitioner students, 19 optometry interns/students/residents, 11 dental students/residents, and 3 physical therapy students.²⁰ In total, 6,223 UC health professions students were trained in VHA facilities during the 2017/2018 training year (Table 4).²⁰ As of 2016, there were 105,907 physicians in California, and of those, 57% completed their GME in California.²⁹ In California in 2015, 74 GME-sponsoring institutions graduated 3,568 residents and fellows, an increase of 10% since 1997.³⁰ Of these sponsoring institutions, 6 of the top 8 programs were UC schools that graduated 48.4% (1,727) of all California residents and fellows in 2015.³⁰

VA Research Collaborations

The VA Office of Research and Development has existed for more than 90 years with a mission to improve veteran health and well-being via research and attract, train, and retain high-caliber researchers. VA provides a rich environment to conduct observational and interventional research due to its large, diverse veteran population, institutional support, and integrated information system with extensive EHR data.⁴¹ The success of the VA in facilitating research is evidenced by the fact that 3 VA investigators have been awarded Nobel prizes, and 7 have received Lasker Foundation Awards.⁴² The size of the VA allows for innovative large-scale research, such as the Million Veteran Program (MVP). The MVP study developed a mega-biobank of VA health records, questionnaires, and blood samples from nearly 1 million veterans to study genetic influences on health and disease and integrate genetic testing into health care delivery.⁴³ In addition to producing high-quality, innovative research, more than 60% of VA investigators also provide direct patient care.⁴²

VA research areas of focus include homelessness, polytrauma, traumatic brain injury, hearing and vision loss, spinal cord injury, mental health, pain management, precision medicine, prosthetics and amputation care, women’s health, and chronic diseases, such as Parkinson and Alzheimer diseases.⁴⁴ The VA estimates that, in 2021, total VA research spending will include a request of $787 million in addition to $370 million from the National Institutes of Health, the Department of Defense, and the Centers for Disease Control and Prevention, and $170 million from other nonfederal sources, for a projected total of $1.3 billion. This budget will support 2,200 projects with direct research and reimbursable employment of 3,275 FTEs,which are key to supporting VA academic affiliations.⁴⁵ These funds translate into substantial benefits to the UC system, including shared research and training resources, grant-funding opportunities for UC faculty, and the ability to recruit top researchers, educators, and clinicians to its institutions.

VA Reliance on Community Care 

The current VHA model is an integrated health care system that provides comprehensive, wraparound services to enrolled veterans, which are cost-effective, high quality, and consistently found to have equal or superior quality of care compared with that in the community.^6,46-50 Despite public criticism about wait times and access to care in the VA system, one study showed that VA wait-time statistics were comparable with or faster than those for community HCPs.^51,52 However, VA care coordination has undergone several changes to address these public criticisms, namely, the Veterans Access, Choice and Accountability Act of 2014 (38 USC § 1703 VACAA) and the VA MISSION Act of 2018 (42 USC § 274). VACAA was designed to increase access to care for veterans who live ≥ 40 miles from VA health care facilities or who are unable to been seen within 30 days of their preferred or clinically appropriate date.⁵³ More than 2 million veterans (almost 25% of VHA-enrolled veterans) have received community care since the inception of VACAA in 2014.⁵⁴

Recently, the MISSION Act mandated developing additional VA-coordinated community-based care through the establishment of a Veterans Community Care Program, which was established using existing VA 2019 fiscal year funds and did not include additional appropriations despite expanded criteria for community care referrals.⁵⁵ Without additional future appropriations, VA funds would be shifted from VA care into community care. While increasing access to community care has in some cases led to care that is faster and closer and that was previously inaccessible in local VA specialty care, these efforts could reduce veteran engagement with the VA system.⁵⁶

The changes implemented in VACAA and the VA MISSION Act were driven by important and valid concerns, including evidence of VA staff and officials covering up service deficiencies.⁵¹ Veterans in rural areas often have limited access to VA resources, and long travel to VAMCs or clinics can be an impediment. Veterans who have chosen community care tended to be those who have poorer health status, who live further away from VA facilities, women, and those who identified as White or Hispanic.^56,57 While VA health care is on average equivalent to or better than community resources, there is significant variability in quality within the VA system. Advocates have argued that providing competition and choice for veterans places pressure on the VA to improve care where it is not meeting expectations. Therefore, access to community care is an important resource for veterans and needs to be implemented effectively and efficiently to help veterans receive the care they need. However, expansion of community care access, depending on how it is implemented, also can have effects on academic partnerships and the education and research missions that should be incorporated into planning.

Each VA health care system receives funding through the Veterans Equitable Reimbursement Allocation (VERA), which provides funds largely based on the number of enrolled veterans and the complexity of the care they receive.⁵⁸ One potential implication of the shift among veterans to community care is a reduction in patients enrolled in VA programs, thus decreasing funding given to the VA to allocate for training and research. By definition, increased VA-managed community care means less opportunity for integrated training that brings together primary, mental health, and substance use care to meet patient needs. The Center for Medicare and Medicaid Services has developed a national initiative to help states develop programs in integrated care, particularly for individuals who are eligible for both Medicare and Medicaid.⁵⁹ For states to develop integrated care, they need trainees who function well in this model. Integrated care training is particularly vulnerable to disruption because any portion of a veteran’s care being transferred to the community can impede integration. In effect, training in integrated care, likely the most efficient and cost-effective approach to health care for reasons discussed earlier, could be reduced as providers and trainees are required to manage and coordinate patient care between separate institutions.³⁵

Educational Impact

The shift in usage from VA to community care has potential implications for academic affiliates, particularly in education and research.⁶⁰ If more people are served in community settings, potentially some VAMCs could be reduced, realigned, or closed. If this restructuring happens, academic partnerships could be impacted negatively. The VA is instituting an Infrastructure Review Commission with the task of examining current VA utilization. If a VA site with an academic affiliate was considered for realignment or closure, the reduction would eliminate the ability of the academic affiliate to provide education and research collaborations at that site.

In a less drastic manner, increasing care in the community may change opportunities for academic affiliates to partner with the VA. As noted, the UC system and California veterans benefit immensely from the VHA as an integrated health care system with dedicated missions of education and research. This partnership is a model in which the VA is the primary source of care for eligible enrolled veterans and provides integrated comprehensive services. If the VA moves to serving primarily as a coordinator of community HCPs rather than a direct provider of health care, academic affiliates would need to make major adjustments to both the education and training models. This change could particularly affect specialty training programs that rely on having adequate volumes of patients to provide an extensive experience to meet training needs. If fewer veterans receive care directly from the VA and are instead dispersed in the community, that will reduce the ability of academic faculty to participate in the education of medical and affiliated trainees and to participate in research in VA settings. It is unclear what other model could replace such a system and be as beneficial to the VA and the academic partners with which it is currently affiliated.

Given the needs that led to the VA increasing access to care and the potential implications discussed for the VA and partnerships with academic affiliates, VA health care systems and academic affiliate partners should consider several steps. These steps involve assessment, coordination, and promotion.

Both the VA and academic affiliates would benefit if the VA shared assessment data on the use of community care, particularly identifying changes that relate to key training and/or research missions. Such data sharing can be critical to determine whether any risks (or potential opportunities) need to be addressed. In addition, increasing research on the outcomes related to both VA care and community-based care is of high value to determine whether the current changes are achieving intended goals. The VA recently funded such work through its research service, and such work is critical for guiding future policy for the VA and for the affiliates.

Coordination among the VA, academic affiliates, and community partners is vital for change. The issue of community care expansion should be a standing item on coordination meetings and shared governance councils between the institutions. It may make sense to establish specific workgroups or committees to coordinate tracking and assessment of the effect of community care expansion on the shared academic mission. One way to address the potential effect of increased community care on the research and education missions would be to include community partners into the partnerships. This strategy could potentially take a number of different forms, from providing education and training to community HCPs, having VA trainees rotate to community settings, or inviting community settings to be research sites for clinical trials. Such partnerships could potentially improve patient care and support the other academic missions. Coordination could be meaningfully improved by having community HCPs access the VA EHR, thus easing communications. Funding is available for EHR access in the VA MISSION Act and should be a high priority as community care expands. The more that community partners can access and connect with the VA EHR the better they will be able to coordinate care.

Third, the VA and its academic partners need to promote and educate veterans, their families, and their advocates on the benefits that are available through VA care and that are enhanced through academic partnerships. While the VA has been the target of justified criticism, many of its strengths addressed here are not broadly recognized. The VA could promote its sharing of staff and resources with the top academic health care institutions in an area and that veterans often have access to resources that otherwise would not be available without the academic affiliate. Making sure veterans are aware of the benefits available can potentially mitigate the need for community care.

Conclusions

Given changes from VACAA and the VA MISSION Act, VA and academic affiliates should be active partners in planning for future health care by providing input and feedback on VA structure to help shape federal and state systems moving forward. Institutions can take steps to steer their futures and meet growing clinical, training, and research needs. The VA and its academic partners in health care research are well positioned to develop projects to assess the effects of these changes. Evaluation of key variables including patient care, education, and research productivity are warranted to guide policymakers as they assess whether these changes in the VA are achieving the expressed goals of improving veteran care. Other opportunities to collaborate in the wake of the MISSION Act remain to be discovered within each academic affiliation. By strengthening working relationships between VA and academic teams, these deeply important partnerships can continue to produce clinical, research, and education outcomes that meet the needs of our veterans, our federal and state health care systems, and our country.

Acknowledgments

Dr. Sells was supported by the Department of Veterans Affairs, Veterans Health Administration, Office of Academic Affiliations VA Quality Scholars Advanced Fellowship Program.

In April 2020, I pledged to focus my editorials on the pandemic. In subsequent editorials I renewed that intention. And it is a promise I have kept during the long plague year for all my editorials. When I announced my plan to write solely on COVID-19, my astute editor asked me, “How are you going to know when to stop?” I reminded myself of his question as I sat down to write each month and never arrived at a satisfactory answer. Nor do I have an answer now for why I am asking readers to release me from my vow—except for the somewhat trivial reason that a year seems enough. Is there more to say about the pandemic? Yes, there is so much more that needs to be discovered and unraveled, contemplated and analyzed; no doubt oceans of print and electronic pages will wash over us in the coming decade from thousands of scientists and journalists commenting on the topic of this public health crisis.²

Nevertheless, I have run the gauntlet of salient subjects within my wheelhouse: The plague year of editorials opened with a primer on public health ethics; the May column studied the duty to care for health care professionals in the midst of the first surge of virus; June examined the controversy around remdesivir and hydroxcholoroquine as medicine frantically sought some way to treat the sick; in July, I took a lighter look at the “Dog Days” of COVID-19 staring my Labrador Retriever mix, Reed, snoozing on his couch on the patio; August celebrated the amazing outreach of the US Department of Defense, US Public Health Service, and US Department of Veterans Affairs (VA) in service to the community; September discussed the adverse effects of the prolonged pandemic on the human psyche and some positive ways of handling the stress; October lamented the exponential rise in substance misuse as human beings struggled to manage the emotional toll of the pandemic; in December, COVID-19 was the sole subject of my annual Best and Worst ethics column; the new year saw the emergency use authorizations of the first and second vaccines and the editorial laid out the critical challenges for vaccination; in February my esteemed colleague Anita Tarzian joined me in an article explaining the ethical approach to vaccine allocation developed by the VA.^3-12

A reader might aptly ask whether I am laying down the COVID-19 gauntlet because I believe the pandemic is over and done with us. The news is full of pundits opining when things will return to normal (if that ever existed or will again) and soothsayers divining the signs of the plague’s end.¹³ What I think is that we are more than done with the pandemic and unfortunately that may be the central cause of its perpetuation; which brings me to Daniel Defoe’s A Journal of the Plague Year.¹

Defoe is better known to most of us if at all from modern films of his best-seller Robinson Crusoe. Yet A Journal of the Plague Year and other books about epidemics have become popular reading as we seek clues to the mystery of how to affirm life amid a death-dealing infectious disease.¹⁴ There is even an emerging lockdown literature genre. (Before anyone asks, I am in no way so pretentious as to suggest my columns should be included in that scholarly body of work).

Defoe’s book chronicles the last episode of the bubonic plague that afflicted London in 1665 and claimed 100,000 lives. Defoe was only 5 years old when the epidemic devastated one of the greatest cities in Europe. In 1772 he published what one recent reviewer called “a fascinating record of trying to cope with the capital’s last plague.”¹⁵ Defoe presciently documented the central reason I think the pandemic may not end anytime soon despite the increasing success of vaccination, at least in the United States. “But the Case was this...that the infection was propagated insensibly, and by such Persons, as were not visibly infected, who neither knew who they infected, or who they were infected by.”¹

Ignorance and apathy are not confined to the streets of 17th century England: We see state after state lift restrictions prematurely, guaranteeing the scientists prediction that the wave now hitting Europe could again breach our shores. Defoe wrote long before germ theory and the ascendancy of public health, yet he knew that the inability or unwillingness to stick close to home kept the plague circulating. “And here I must observe again, that this Necessity of going out of our Houses to buy Provisions, was in a Great Measure the Ruin of the whole City, for the people catch’d the Distemper, on those Occasions, one of another...”¹ While provisions may equate to food for many, for others necessities include going to bars, dining inside restaurants, and working out at gyms—all are natural laboratories for the spread and mutation of COVID-19 into variants against which physicians warn that the vaccine may not offer protection.

Defoe’s insights were at least in part due to his distance from the horror of the plague, which enabled him to study it with both empathy and objectivity, critical thinking, and creative observation. Similarly, it is time to take a brief breathing space from the pandemic as the central preoccupation of our existence: not just for me but for all of us to the extent possible given that unlike Defoe’s epoch it is still very much our reality. Even a few moments imagining a world without COVID-19 or more accurately one where it is under some reasonable control can help us reconceive how we want to live in it.

Can we use that luminal period to reenvision society along the lines Defoe idealistically drew even while we contribute to the collective search for the Holy Grail of herd immunity? During this second plague year, in coming editorials and in my own small circle of concern I will try to take a different less frustrated, embittered view of our lives scarred as they may be. It is only such a reorientation of perspectives in the shadow of so much death and suffering that can give us the energy and empathy to wear masks, go only where we must, follow public health measures and direction, and persuade the hesitant to be vaccinated so this truly is the last plague year at least for a long, quiet while.

In April 2020, I pledged to focus my editorials on the pandemic. In subsequent editorials I renewed that intention. And it is a promise I have kept during the long plague year for all my editorials. When I announced my plan to write solely on COVID-19, my astute editor asked me, “How are you going to know when to stop?” I reminded myself of his question as I sat down to write each month and never arrived at a satisfactory answer. Nor do I have an answer now for why I am asking readers to release me from my vow—except for the somewhat trivial reason that a year seems enough. Is there more to say about the pandemic? Yes, there is so much more that needs to be discovered and unraveled, contemplated and analyzed; no doubt oceans of print and electronic pages will wash over us in the coming decade from thousands of scientists and journalists commenting on the topic of this public health crisis.²

Nevertheless, I have run the gauntlet of salient subjects within my wheelhouse: The plague year of editorials opened with a primer on public health ethics; the May column studied the duty to care for health care professionals in the midst of the first surge of virus; June examined the controversy around remdesivir and hydroxcholoroquine as medicine frantically sought some way to treat the sick; in July, I took a lighter look at the “Dog Days” of COVID-19 staring my Labrador Retriever mix, Reed, snoozing on his couch on the patio; August celebrated the amazing outreach of the US Department of Defense, US Public Health Service, and US Department of Veterans Affairs (VA) in service to the community; September discussed the adverse effects of the prolonged pandemic on the human psyche and some positive ways of handling the stress; October lamented the exponential rise in substance misuse as human beings struggled to manage the emotional toll of the pandemic; in December, COVID-19 was the sole subject of my annual Best and Worst ethics column; the new year saw the emergency use authorizations of the first and second vaccines and the editorial laid out the critical challenges for vaccination; in February my esteemed colleague Anita Tarzian joined me in an article explaining the ethical approach to vaccine allocation developed by the VA.^3-12

A reader might aptly ask whether I am laying down the COVID-19 gauntlet because I believe the pandemic is over and done with us. The news is full of pundits opining when things will return to normal (if that ever existed or will again) and soothsayers divining the signs of the plague’s end.¹³ What I think is that we are more than done with the pandemic and unfortunately that may be the central cause of its perpetuation; which brings me to Daniel Defoe’s A Journal of the Plague Year.¹

Defoe is better known to most of us if at all from modern films of his best-seller Robinson Crusoe. Yet A Journal of the Plague Year and other books about epidemics have become popular reading as we seek clues to the mystery of how to affirm life amid a death-dealing infectious disease.¹⁴ There is even an emerging lockdown literature genre. (Before anyone asks, I am in no way so pretentious as to suggest my columns should be included in that scholarly body of work).

Defoe’s book chronicles the last episode of the bubonic plague that afflicted London in 1665 and claimed 100,000 lives. Defoe was only 5 years old when the epidemic devastated one of the greatest cities in Europe. In 1772 he published what one recent reviewer called “a fascinating record of trying to cope with the capital’s last plague.”¹⁵ Defoe presciently documented the central reason I think the pandemic may not end anytime soon despite the increasing success of vaccination, at least in the United States. “But the Case was this...that the infection was propagated insensibly, and by such Persons, as were not visibly infected, who neither knew who they infected, or who they were infected by.”¹

Ignorance and apathy are not confined to the streets of 17th century England: We see state after state lift restrictions prematurely, guaranteeing the scientists prediction that the wave now hitting Europe could again breach our shores. Defoe wrote long before germ theory and the ascendancy of public health, yet he knew that the inability or unwillingness to stick close to home kept the plague circulating. “And here I must observe again, that this Necessity of going out of our Houses to buy Provisions, was in a Great Measure the Ruin of the whole City, for the people catch’d the Distemper, on those Occasions, one of another...”¹ While provisions may equate to food for many, for others necessities include going to bars, dining inside restaurants, and working out at gyms—all are natural laboratories for the spread and mutation of COVID-19 into variants against which physicians warn that the vaccine may not offer protection.

Defoe’s insights were at least in part due to his distance from the horror of the plague, which enabled him to study it with both empathy and objectivity, critical thinking, and creative observation. Similarly, it is time to take a brief breathing space from the pandemic as the central preoccupation of our existence: not just for me but for all of us to the extent possible given that unlike Defoe’s epoch it is still very much our reality. Even a few moments imagining a world without COVID-19 or more accurately one where it is under some reasonable control can help us reconceive how we want to live in it.

Can we use that luminal period to reenvision society along the lines Defoe idealistically drew even while we contribute to the collective search for the Holy Grail of herd immunity? During this second plague year, in coming editorials and in my own small circle of concern I will try to take a different less frustrated, embittered view of our lives scarred as they may be. It is only such a reorientation of perspectives in the shadow of so much death and suffering that can give us the energy and empathy to wear masks, go only where we must, follow public health measures and direction, and persuade the hesitant to be vaccinated so this truly is the last plague year at least for a long, quiet while.

In April 2020, I pledged to focus my editorials on the pandemic. In subsequent editorials I renewed that intention. And it is a promise I have kept during the long plague year for all my editorials. When I announced my plan to write solely on COVID-19, my astute editor asked me, “How are you going to know when to stop?” I reminded myself of his question as I sat down to write each month and never arrived at a satisfactory answer. Nor do I have an answer now for why I am asking readers to release me from my vow—except for the somewhat trivial reason that a year seems enough. Is there more to say about the pandemic? Yes, there is so much more that needs to be discovered and unraveled, contemplated and analyzed; no doubt oceans of print and electronic pages will wash over us in the coming decade from thousands of scientists and journalists commenting on the topic of this public health crisis.²

Nevertheless, I have run the gauntlet of salient subjects within my wheelhouse: The plague year of editorials opened with a primer on public health ethics; the May column studied the duty to care for health care professionals in the midst of the first surge of virus; June examined the controversy around remdesivir and hydroxcholoroquine as medicine frantically sought some way to treat the sick; in July, I took a lighter look at the “Dog Days” of COVID-19 staring my Labrador Retriever mix, Reed, snoozing on his couch on the patio; August celebrated the amazing outreach of the US Department of Defense, US Public Health Service, and US Department of Veterans Affairs (VA) in service to the community; September discussed the adverse effects of the prolonged pandemic on the human psyche and some positive ways of handling the stress; October lamented the exponential rise in substance misuse as human beings struggled to manage the emotional toll of the pandemic; in December, COVID-19 was the sole subject of my annual Best and Worst ethics column; the new year saw the emergency use authorizations of the first and second vaccines and the editorial laid out the critical challenges for vaccination; in February my esteemed colleague Anita Tarzian joined me in an article explaining the ethical approach to vaccine allocation developed by the VA.^3-12

A reader might aptly ask whether I am laying down the COVID-19 gauntlet because I believe the pandemic is over and done with us. The news is full of pundits opining when things will return to normal (if that ever existed or will again) and soothsayers divining the signs of the plague’s end.¹³ What I think is that we are more than done with the pandemic and unfortunately that may be the central cause of its perpetuation; which brings me to Daniel Defoe’s A Journal of the Plague Year.¹

Defoe is better known to most of us if at all from modern films of his best-seller Robinson Crusoe. Yet A Journal of the Plague Year and other books about epidemics have become popular reading as we seek clues to the mystery of how to affirm life amid a death-dealing infectious disease.¹⁴ There is even an emerging lockdown literature genre. (Before anyone asks, I am in no way so pretentious as to suggest my columns should be included in that scholarly body of work).

Defoe’s book chronicles the last episode of the bubonic plague that afflicted London in 1665 and claimed 100,000 lives. Defoe was only 5 years old when the epidemic devastated one of the greatest cities in Europe. In 1772 he published what one recent reviewer called “a fascinating record of trying to cope with the capital’s last plague.”¹⁵ Defoe presciently documented the central reason I think the pandemic may not end anytime soon despite the increasing success of vaccination, at least in the United States. “But the Case was this...that the infection was propagated insensibly, and by such Persons, as were not visibly infected, who neither knew who they infected, or who they were infected by.”¹

Ignorance and apathy are not confined to the streets of 17th century England: We see state after state lift restrictions prematurely, guaranteeing the scientists prediction that the wave now hitting Europe could again breach our shores. Defoe wrote long before germ theory and the ascendancy of public health, yet he knew that the inability or unwillingness to stick close to home kept the plague circulating. “And here I must observe again, that this Necessity of going out of our Houses to buy Provisions, was in a Great Measure the Ruin of the whole City, for the people catch’d the Distemper, on those Occasions, one of another...”¹ While provisions may equate to food for many, for others necessities include going to bars, dining inside restaurants, and working out at gyms—all are natural laboratories for the spread and mutation of COVID-19 into variants against which physicians warn that the vaccine may not offer protection.

Defoe’s insights were at least in part due to his distance from the horror of the plague, which enabled him to study it with both empathy and objectivity, critical thinking, and creative observation. Similarly, it is time to take a brief breathing space from the pandemic as the central preoccupation of our existence: not just for me but for all of us to the extent possible given that unlike Defoe’s epoch it is still very much our reality. Even a few moments imagining a world without COVID-19 or more accurately one where it is under some reasonable control can help us reconceive how we want to live in it.

Can we use that luminal period to reenvision society along the lines Defoe idealistically drew even while we contribute to the collective search for the Holy Grail of herd immunity? During this second plague year, in coming editorials and in my own small circle of concern I will try to take a different less frustrated, embittered view of our lives scarred as they may be. It is only such a reorientation of perspectives in the shadow of so much death and suffering that can give us the energy and empathy to wear masks, go only where we must, follow public health measures and direction, and persuade the hesitant to be vaccinated so this truly is the last plague year at least for a long, quiet while.

Metabolic alkalosis, a disorder that causes elevations in serum bicarbonate and arterial pH, is a common metabolic abnormality found in nearly half of hospitalized patients but is rare in patients with end-stage renal disease (ESRD) on hemodialysis (HD) during the pretreatment state. The problem seems to arise due to a high rate of older patients with multiple comorbidities and malnutrition who are undergoing HD. Metabolic alkalosis is associated with increased morbidity and mortality. In this report, we present a case of metabolic alkalosis, describe an innovative approach to manage metabolic alkalosis in the dialysis population, and review the pathophysiology.

Case Presentation

A 63-year-old female with emphysema, diabetic nephropathy, and ESRD on regular HD for 2 months by a tunneled subclavian vein catheter was admitted with 2 weeks of orthopnea and leg swelling. The review of systems was negative for chest pain, cough, wheeze, or sputum production. She was a former smoker with no alcohol or drug misuse. The patient was taking carvedilol 25 mg daily, furosemide 20 mg twice daily, basal insulin premeal, lisinopril 40 mg daily, pantoprazole 40 mg daily, calcium carbonate 400 mg 3 times daily, ferrous sulphate 325 mg daily, and a vilanterol/tiotropium inhaler once daily. Her dialysate outpatient prescription included sodium 140 mEq/L, potassium 2 mEq/L, calcium 2.5 mEq/L, and bicarbonate 36 mEq/L. Our dialysis unit used NaturaLyte dry pack for bicarbonate dialysis.

The patient appeared tachypneic with 26 respirations/min, oxygen saturation of 89% on room air, which improved to 94% on a 2 L nasal cannula. Her heart rate was 89 beats/min, blood pressure was 129/72 mm Hg, and body mass index was 21.2. The physical examination revealed jugular venous distension, lung crackles, reduced air entry, and pedal edema. Muscle wasting was noted in the arms and thighs. The tunnel catheter did not appear infected.

The patient’s blood work showed sodium, 136 (reference, 132-140) mmol/L; potassium, 4.3 (reference, 3.5-5.0) mmol/L; chloride, 89 (reference, 98-111) mmol/L; total CO₂, 36 (reference, 24-28) mEq/L; blood urea nitrogen, 21 (reference, 7-21) mg/dL; creatinine 3.4 (reference, 0.5-1.4) mg/dL; and albumin, 2.7 (reference, 3.7-5.0) mg/dL. Arterial gases showed pH, 7.56 (reference, 7.35-7.45), partial CO₂, 47 (reference, 35-45) mm Hg; bicarbonate, 42 (reference, 22-26) mEq/L; partial O₂, 54 (reference, 75 to 100) mm Hg. Brain natriuretic peptide was 2,800 (normal, < 100) pg/mL with a normal troponin. X-rays showed pulmonary congestion and bilateral pleural effusions that were transudative on fluid analysis. An echocardiogram showed ejection fraction of 20 to 25% with normal valves (baseline ejection fraction of 60%-65%). A coronary arteriogram revealed severe nonischemic cardiomyopathy.

Treatment

To reduce bicarbonate levels, 3 L of normal saline solution were infused prefilter during HD, and ultrafiltration (UF) of 4.5 L achieved a net UF of -1.5 L over 3.5 hours on lower dialysate bicarbonate (30 mEq/L). Good catheter flow was achieved with a blood flow rate of 350 mL/min and a dialysate flow of 700 mL/min. Venous blood gases and basic serum metabolic panels were obtained throughout the first HD session (Table 1). Improvement in pH from 7.5 to 7.43 and in total CO₂ from 36 to 30 mEq/L were noted after the treatment. Subsequently, we used the same membrane (Optiflux F160NRe) for 2 consecutive daily treatments to remove excess fluid and prevent worsening alkalosis using the same minimal bicarbonate bath, but no further normal saline solution was given.

Outcome

Volume overload was controlled as needed with UF. The bicarbonate did not drop after the second HD session, suggesting low organic acid production in the intradialytic period. By shortening the duration of dialysis to 3 hours and improving nutritional intake, we achieved dry weight, and the patient was discharged home with a total CO₂ of 25 mEq/L. Outpatient dialysis sessions were arranged to run at shorter duration (3 hours compared with 3.5 hours) and use low bicarbonate dialysate. The patient was admitted several times afterward for acute decompensated heart failure, but in all those admissions, her bicarbonate was in the normal-to-high range, between 23 and 30 mEq/L.

Discussion

Metabolic alkalosis is relatively rare in ESRD patients on HD. Particularly in the predialysis period, but with the growing number of older patients undergoing HD and the aggressive treatment of acidosis with relatively higher buffer concentrations; there has been an increase in the incidence of metabolic alkalosis in patients on HD. In the Fresenius Medical Care (FMC) prevalent HD patient study, predialysis bicarbonate levels have increased overtime from a mean (SD)22.9 (3.1) mEq/L in 2004 to a mean (SD) 24.1 (3.5) mEq/L in September 2011, with 25% of patients > 26.0 mEq/L compared with only 6% in 2004.¹ The condition has been associated with cardiac arrhythmia, intradialytic hypocalcemia, hypokalemia, hypercapnia, hypoxia, accelerated hypertension, and seizure.^2-4 Metabolic alkalosis may be associated with increased mortality.^5-7 However, the effect dissipated after adjusting for inflammation and nutritional status.⁶

Our patient had primary metabolic alkalosis evident by her high pH of 7.56 and high total CO₂ of 36 mEq/L. The serum total CO₂ reflects the metabolic status more accurately than the blood gas bicarbonate, which is prone to calculation error by the Henderson-Hasselbalch equation. Her respiratory compensation for the metabolic alkalosis was appropriate, with an increase of arterial PaCO₂ to 47 mm Hg (expected PaCO₂ = 40 + 0.7[HCO₃-24] = 48.4). She had normal baseline PaCO₂ in the weeks prior to admission. Due to lack of residual urine output, < 50 mL/d, her metabolic alkalosis could not be attributed to the generation of bicarbonate by the kidneys, or ameliorated by dumping of excess bicarbonate, which explained why her metabolic alkalosis was severe. On the other hand, respiratory distress may have hindered the appropriate CO₂ retention.

In patients with ESRD on HD who have no residual urine output, causes of metabolic alkalosis are limited to loss of net acid or gain of alkali through the gastrointestinal tract; our patient had none of these. Similarly, all renal causes of metabolic alkalosis are not applicable to our patient, including mineralocorticoid excess and contraction alkalosis. In patients with preserved kidney function, loop diuretics can induce alkalosis through enhanced tubular absorption of HCO₃. While acetazolamide can mitigate this scenario by blocking carbonic anhydrase in the luminal border of the collecting ducts resulting in excretion of bicarbonate in the urine, our patient had negligible urine output despite being on furosemide 20 mg twice daily, making this an unlikely cause.

Severe metabolic alkalosis in dialysis patients has been reported with cocaine use, pica ingestion, and citrate load as in plasma exchange, massive transfusions, and regional anticoagulation.^2,8-11 Although calcium carbonate intake can contribute to alkalosis, her small daily dose of 1,200 mg contains approximately 12 mEq of carbonate, which is not a significant contributor to the alkalosis.

With all other causes excluded, the metabolic alkalosis in our patient is presumed to result from the bicarbonate-rich dialysate. Since the majority of patients with ESRD are acidotic before dialysis, the dialysate bicarbonate is set at a higher than normal physiologic level to bring the pH close to or even higher than normal after dialysis. The patient had been dialyzed with NaturaLyte as an outpatient, which was set at the dialysis unit default mode of 36 mEq/L. This form of alkalosis has been reported to peak immediately after treatment but in most patients returns to the predialysis acidotic state due to endogenous acid production.^1,4,12 Normally, muscles play a significant role in buffering excess bicarbonate in patients with nonfunctioning kidneys; hence, malnutrition with muscle wasting tends to propagate and maintain alkalosis, as in our patient.

Managing alkalosis in patients on dialysis can be challenging and is often directed at identifying potential causes like overzealous bicarbonate dialysate and addressing comorbidities, especially malnutrition.^6,7 Bicarbonate delivery can be set on dialysis machines as low as 20 mEq/L. However, the reliability of correcting serum bicarbonate by adjusting bicarbonate-based dialysis products is in question as these products deliver additional buffering capacity through mixing and metabolism of acetate, acetic acid, or citric acid (Table 2).

Conclusions

Attention should be paid to detect elevated predialysis serum bicarbonate levels in ESRD patients on HD, especially those with values above 27 mmol/L due to higher mortality.^6,7 Treatment of these patients is more challenging than for those who are acidotic predialysis, especially when alkalosis is compounded by malnutrition. Mitigation of this problem is achieved by using a lower bicarbonate bath and the shortest effective dialysis duration that achieves adequate clearance. Poor clearance also deleteriously affects patient nutrition and well-being. We have shown that normal saline solution infusion with concurrent removal by UF can correct pretreatment metabolic alkalosis when other measures are inadequate.

Metabolic alkalosis, a disorder that causes elevations in serum bicarbonate and arterial pH, is a common metabolic abnormality found in nearly half of hospitalized patients but is rare in patients with end-stage renal disease (ESRD) on hemodialysis (HD) during the pretreatment state. The problem seems to arise due to a high rate of older patients with multiple comorbidities and malnutrition who are undergoing HD. Metabolic alkalosis is associated with increased morbidity and mortality. In this report, we present a case of metabolic alkalosis, describe an innovative approach to manage metabolic alkalosis in the dialysis population, and review the pathophysiology.

Case Presentation

A 63-year-old female with emphysema, diabetic nephropathy, and ESRD on regular HD for 2 months by a tunneled subclavian vein catheter was admitted with 2 weeks of orthopnea and leg swelling. The review of systems was negative for chest pain, cough, wheeze, or sputum production. She was a former smoker with no alcohol or drug misuse. The patient was taking carvedilol 25 mg daily, furosemide 20 mg twice daily, basal insulin premeal, lisinopril 40 mg daily, pantoprazole 40 mg daily, calcium carbonate 400 mg 3 times daily, ferrous sulphate 325 mg daily, and a vilanterol/tiotropium inhaler once daily. Her dialysate outpatient prescription included sodium 140 mEq/L, potassium 2 mEq/L, calcium 2.5 mEq/L, and bicarbonate 36 mEq/L. Our dialysis unit used NaturaLyte dry pack for bicarbonate dialysis.

The patient appeared tachypneic with 26 respirations/min, oxygen saturation of 89% on room air, which improved to 94% on a 2 L nasal cannula. Her heart rate was 89 beats/min, blood pressure was 129/72 mm Hg, and body mass index was 21.2. The physical examination revealed jugular venous distension, lung crackles, reduced air entry, and pedal edema. Muscle wasting was noted in the arms and thighs. The tunnel catheter did not appear infected.

The patient’s blood work showed sodium, 136 (reference, 132-140) mmol/L; potassium, 4.3 (reference, 3.5-5.0) mmol/L; chloride, 89 (reference, 98-111) mmol/L; total CO₂, 36 (reference, 24-28) mEq/L; blood urea nitrogen, 21 (reference, 7-21) mg/dL; creatinine 3.4 (reference, 0.5-1.4) mg/dL; and albumin, 2.7 (reference, 3.7-5.0) mg/dL. Arterial gases showed pH, 7.56 (reference, 7.35-7.45), partial CO₂, 47 (reference, 35-45) mm Hg; bicarbonate, 42 (reference, 22-26) mEq/L; partial O₂, 54 (reference, 75 to 100) mm Hg. Brain natriuretic peptide was 2,800 (normal, < 100) pg/mL with a normal troponin. X-rays showed pulmonary congestion and bilateral pleural effusions that were transudative on fluid analysis. An echocardiogram showed ejection fraction of 20 to 25% with normal valves (baseline ejection fraction of 60%-65%). A coronary arteriogram revealed severe nonischemic cardiomyopathy.

Treatment

To reduce bicarbonate levels, 3 L of normal saline solution were infused prefilter during HD, and ultrafiltration (UF) of 4.5 L achieved a net UF of -1.5 L over 3.5 hours on lower dialysate bicarbonate (30 mEq/L). Good catheter flow was achieved with a blood flow rate of 350 mL/min and a dialysate flow of 700 mL/min. Venous blood gases and basic serum metabolic panels were obtained throughout the first HD session (Table 1). Improvement in pH from 7.5 to 7.43 and in total CO₂ from 36 to 30 mEq/L were noted after the treatment. Subsequently, we used the same membrane (Optiflux F160NRe) for 2 consecutive daily treatments to remove excess fluid and prevent worsening alkalosis using the same minimal bicarbonate bath, but no further normal saline solution was given.

Outcome

Volume overload was controlled as needed with UF. The bicarbonate did not drop after the second HD session, suggesting low organic acid production in the intradialytic period. By shortening the duration of dialysis to 3 hours and improving nutritional intake, we achieved dry weight, and the patient was discharged home with a total CO₂ of 25 mEq/L. Outpatient dialysis sessions were arranged to run at shorter duration (3 hours compared with 3.5 hours) and use low bicarbonate dialysate. The patient was admitted several times afterward for acute decompensated heart failure, but in all those admissions, her bicarbonate was in the normal-to-high range, between 23 and 30 mEq/L.

Discussion

Metabolic alkalosis is relatively rare in ESRD patients on HD. Particularly in the predialysis period, but with the growing number of older patients undergoing HD and the aggressive treatment of acidosis with relatively higher buffer concentrations; there has been an increase in the incidence of metabolic alkalosis in patients on HD. In the Fresenius Medical Care (FMC) prevalent HD patient study, predialysis bicarbonate levels have increased overtime from a mean (SD)22.9 (3.1) mEq/L in 2004 to a mean (SD) 24.1 (3.5) mEq/L in September 2011, with 25% of patients > 26.0 mEq/L compared with only 6% in 2004.¹ The condition has been associated with cardiac arrhythmia, intradialytic hypocalcemia, hypokalemia, hypercapnia, hypoxia, accelerated hypertension, and seizure.^2-4 Metabolic alkalosis may be associated with increased mortality.^5-7 However, the effect dissipated after adjusting for inflammation and nutritional status.⁶

Our patient had primary metabolic alkalosis evident by her high pH of 7.56 and high total CO₂ of 36 mEq/L. The serum total CO₂ reflects the metabolic status more accurately than the blood gas bicarbonate, which is prone to calculation error by the Henderson-Hasselbalch equation. Her respiratory compensation for the metabolic alkalosis was appropriate, with an increase of arterial PaCO₂ to 47 mm Hg (expected PaCO₂ = 40 + 0.7[HCO₃-24] = 48.4). She had normal baseline PaCO₂ in the weeks prior to admission. Due to lack of residual urine output, < 50 mL/d, her metabolic alkalosis could not be attributed to the generation of bicarbonate by the kidneys, or ameliorated by dumping of excess bicarbonate, which explained why her metabolic alkalosis was severe. On the other hand, respiratory distress may have hindered the appropriate CO₂ retention.

In patients with ESRD on HD who have no residual urine output, causes of metabolic alkalosis are limited to loss of net acid or gain of alkali through the gastrointestinal tract; our patient had none of these. Similarly, all renal causes of metabolic alkalosis are not applicable to our patient, including mineralocorticoid excess and contraction alkalosis. In patients with preserved kidney function, loop diuretics can induce alkalosis through enhanced tubular absorption of HCO₃. While acetazolamide can mitigate this scenario by blocking carbonic anhydrase in the luminal border of the collecting ducts resulting in excretion of bicarbonate in the urine, our patient had negligible urine output despite being on furosemide 20 mg twice daily, making this an unlikely cause.

Severe metabolic alkalosis in dialysis patients has been reported with cocaine use, pica ingestion, and citrate load as in plasma exchange, massive transfusions, and regional anticoagulation.^2,8-11 Although calcium carbonate intake can contribute to alkalosis, her small daily dose of 1,200 mg contains approximately 12 mEq of carbonate, which is not a significant contributor to the alkalosis.

With all other causes excluded, the metabolic alkalosis in our patient is presumed to result from the bicarbonate-rich dialysate. Since the majority of patients with ESRD are acidotic before dialysis, the dialysate bicarbonate is set at a higher than normal physiologic level to bring the pH close to or even higher than normal after dialysis. The patient had been dialyzed with NaturaLyte as an outpatient, which was set at the dialysis unit default mode of 36 mEq/L. This form of alkalosis has been reported to peak immediately after treatment but in most patients returns to the predialysis acidotic state due to endogenous acid production.^1,4,12 Normally, muscles play a significant role in buffering excess bicarbonate in patients with nonfunctioning kidneys; hence, malnutrition with muscle wasting tends to propagate and maintain alkalosis, as in our patient.

Managing alkalosis in patients on dialysis can be challenging and is often directed at identifying potential causes like overzealous bicarbonate dialysate and addressing comorbidities, especially malnutrition.^6,7 Bicarbonate delivery can be set on dialysis machines as low as 20 mEq/L. However, the reliability of correcting serum bicarbonate by adjusting bicarbonate-based dialysis products is in question as these products deliver additional buffering capacity through mixing and metabolism of acetate, acetic acid, or citric acid (Table 2).

Conclusions

Attention should be paid to detect elevated predialysis serum bicarbonate levels in ESRD patients on HD, especially those with values above 27 mmol/L due to higher mortality.^6,7 Treatment of these patients is more challenging than for those who are acidotic predialysis, especially when alkalosis is compounded by malnutrition. Mitigation of this problem is achieved by using a lower bicarbonate bath and the shortest effective dialysis duration that achieves adequate clearance. Poor clearance also deleteriously affects patient nutrition and well-being. We have shown that normal saline solution infusion with concurrent removal by UF can correct pretreatment metabolic alkalosis when other measures are inadequate.

Metabolic alkalosis, a disorder that causes elevations in serum bicarbonate and arterial pH, is a common metabolic abnormality found in nearly half of hospitalized patients but is rare in patients with end-stage renal disease (ESRD) on hemodialysis (HD) during the pretreatment state. The problem seems to arise due to a high rate of older patients with multiple comorbidities and malnutrition who are undergoing HD. Metabolic alkalosis is associated with increased morbidity and mortality. In this report, we present a case of metabolic alkalosis, describe an innovative approach to manage metabolic alkalosis in the dialysis population, and review the pathophysiology.

Case Presentation

A 63-year-old female with emphysema, diabetic nephropathy, and ESRD on regular HD for 2 months by a tunneled subclavian vein catheter was admitted with 2 weeks of orthopnea and leg swelling. The review of systems was negative for chest pain, cough, wheeze, or sputum production. She was a former smoker with no alcohol or drug misuse. The patient was taking carvedilol 25 mg daily, furosemide 20 mg twice daily, basal insulin premeal, lisinopril 40 mg daily, pantoprazole 40 mg daily, calcium carbonate 400 mg 3 times daily, ferrous sulphate 325 mg daily, and a vilanterol/tiotropium inhaler once daily. Her dialysate outpatient prescription included sodium 140 mEq/L, potassium 2 mEq/L, calcium 2.5 mEq/L, and bicarbonate 36 mEq/L. Our dialysis unit used NaturaLyte dry pack for bicarbonate dialysis.

The patient appeared tachypneic with 26 respirations/min, oxygen saturation of 89% on room air, which improved to 94% on a 2 L nasal cannula. Her heart rate was 89 beats/min, blood pressure was 129/72 mm Hg, and body mass index was 21.2. The physical examination revealed jugular venous distension, lung crackles, reduced air entry, and pedal edema. Muscle wasting was noted in the arms and thighs. The tunnel catheter did not appear infected.

The patient’s blood work showed sodium, 136 (reference, 132-140) mmol/L; potassium, 4.3 (reference, 3.5-5.0) mmol/L; chloride, 89 (reference, 98-111) mmol/L; total CO₂, 36 (reference, 24-28) mEq/L; blood urea nitrogen, 21 (reference, 7-21) mg/dL; creatinine 3.4 (reference, 0.5-1.4) mg/dL; and albumin, 2.7 (reference, 3.7-5.0) mg/dL. Arterial gases showed pH, 7.56 (reference, 7.35-7.45), partial CO₂, 47 (reference, 35-45) mm Hg; bicarbonate, 42 (reference, 22-26) mEq/L; partial O₂, 54 (reference, 75 to 100) mm Hg. Brain natriuretic peptide was 2,800 (normal, < 100) pg/mL with a normal troponin. X-rays showed pulmonary congestion and bilateral pleural effusions that were transudative on fluid analysis. An echocardiogram showed ejection fraction of 20 to 25% with normal valves (baseline ejection fraction of 60%-65%). A coronary arteriogram revealed severe nonischemic cardiomyopathy.

Treatment

To reduce bicarbonate levels, 3 L of normal saline solution were infused prefilter during HD, and ultrafiltration (UF) of 4.5 L achieved a net UF of -1.5 L over 3.5 hours on lower dialysate bicarbonate (30 mEq/L). Good catheter flow was achieved with a blood flow rate of 350 mL/min and a dialysate flow of 700 mL/min. Venous blood gases and basic serum metabolic panels were obtained throughout the first HD session (Table 1). Improvement in pH from 7.5 to 7.43 and in total CO₂ from 36 to 30 mEq/L were noted after the treatment. Subsequently, we used the same membrane (Optiflux F160NRe) for 2 consecutive daily treatments to remove excess fluid and prevent worsening alkalosis using the same minimal bicarbonate bath, but no further normal saline solution was given.

Outcome

Volume overload was controlled as needed with UF. The bicarbonate did not drop after the second HD session, suggesting low organic acid production in the intradialytic period. By shortening the duration of dialysis to 3 hours and improving nutritional intake, we achieved dry weight, and the patient was discharged home with a total CO₂ of 25 mEq/L. Outpatient dialysis sessions were arranged to run at shorter duration (3 hours compared with 3.5 hours) and use low bicarbonate dialysate. The patient was admitted several times afterward for acute decompensated heart failure, but in all those admissions, her bicarbonate was in the normal-to-high range, between 23 and 30 mEq/L.

Discussion

Metabolic alkalosis is relatively rare in ESRD patients on HD. Particularly in the predialysis period, but with the growing number of older patients undergoing HD and the aggressive treatment of acidosis with relatively higher buffer concentrations; there has been an increase in the incidence of metabolic alkalosis in patients on HD. In the Fresenius Medical Care (FMC) prevalent HD patient study, predialysis bicarbonate levels have increased overtime from a mean (SD)22.9 (3.1) mEq/L in 2004 to a mean (SD) 24.1 (3.5) mEq/L in September 2011, with 25% of patients > 26.0 mEq/L compared with only 6% in 2004.¹ The condition has been associated with cardiac arrhythmia, intradialytic hypocalcemia, hypokalemia, hypercapnia, hypoxia, accelerated hypertension, and seizure.^2-4 Metabolic alkalosis may be associated with increased mortality.^5-7 However, the effect dissipated after adjusting for inflammation and nutritional status.⁶

Our patient had primary metabolic alkalosis evident by her high pH of 7.56 and high total CO₂ of 36 mEq/L. The serum total CO₂ reflects the metabolic status more accurately than the blood gas bicarbonate, which is prone to calculation error by the Henderson-Hasselbalch equation. Her respiratory compensation for the metabolic alkalosis was appropriate, with an increase of arterial PaCO₂ to 47 mm Hg (expected PaCO₂ = 40 + 0.7[HCO₃-24] = 48.4). She had normal baseline PaCO₂ in the weeks prior to admission. Due to lack of residual urine output, < 50 mL/d, her metabolic alkalosis could not be attributed to the generation of bicarbonate by the kidneys, or ameliorated by dumping of excess bicarbonate, which explained why her metabolic alkalosis was severe. On the other hand, respiratory distress may have hindered the appropriate CO₂ retention.

In patients with ESRD on HD who have no residual urine output, causes of metabolic alkalosis are limited to loss of net acid or gain of alkali through the gastrointestinal tract; our patient had none of these. Similarly, all renal causes of metabolic alkalosis are not applicable to our patient, including mineralocorticoid excess and contraction alkalosis. In patients with preserved kidney function, loop diuretics can induce alkalosis through enhanced tubular absorption of HCO₃. While acetazolamide can mitigate this scenario by blocking carbonic anhydrase in the luminal border of the collecting ducts resulting in excretion of bicarbonate in the urine, our patient had negligible urine output despite being on furosemide 20 mg twice daily, making this an unlikely cause.

Severe metabolic alkalosis in dialysis patients has been reported with cocaine use, pica ingestion, and citrate load as in plasma exchange, massive transfusions, and regional anticoagulation.^2,8-11 Although calcium carbonate intake can contribute to alkalosis, her small daily dose of 1,200 mg contains approximately 12 mEq of carbonate, which is not a significant contributor to the alkalosis.

With all other causes excluded, the metabolic alkalosis in our patient is presumed to result from the bicarbonate-rich dialysate. Since the majority of patients with ESRD are acidotic before dialysis, the dialysate bicarbonate is set at a higher than normal physiologic level to bring the pH close to or even higher than normal after dialysis. The patient had been dialyzed with NaturaLyte as an outpatient, which was set at the dialysis unit default mode of 36 mEq/L. This form of alkalosis has been reported to peak immediately after treatment but in most patients returns to the predialysis acidotic state due to endogenous acid production.^1,4,12 Normally, muscles play a significant role in buffering excess bicarbonate in patients with nonfunctioning kidneys; hence, malnutrition with muscle wasting tends to propagate and maintain alkalosis, as in our patient.

Managing alkalosis in patients on dialysis can be challenging and is often directed at identifying potential causes like overzealous bicarbonate dialysate and addressing comorbidities, especially malnutrition.^6,7 Bicarbonate delivery can be set on dialysis machines as low as 20 mEq/L. However, the reliability of correcting serum bicarbonate by adjusting bicarbonate-based dialysis products is in question as these products deliver additional buffering capacity through mixing and metabolism of acetate, acetic acid, or citric acid (Table 2).

Conclusions

Attention should be paid to detect elevated predialysis serum bicarbonate levels in ESRD patients on HD, especially those with values above 27 mmol/L due to higher mortality.^6,7 Treatment of these patients is more challenging than for those who are acidotic predialysis, especially when alkalosis is compounded by malnutrition. Mitigation of this problem is achieved by using a lower bicarbonate bath and the shortest effective dialysis duration that achieves adequate clearance. Poor clearance also deleteriously affects patient nutrition and well-being. We have shown that normal saline solution infusion with concurrent removal by UF can correct pretreatment metabolic alkalosis when other measures are inadequate.

Unlike high-risk adenomas (HRAs), low-risk adenomas (LRAs) have a minimal association with risk of metachronous colorectal cancer (CRC), and no relationship with odds of metachronous CRC-related mortality, according to a meta-analysis of more than 500,000 individuals.

These findings should impact surveillance guidelines and make follow-up the same for individuals with LRAs or no adenomas, reported lead author Abhiram Duvvuri, MD, of the division of gastroenterology and hepatology at the University of Kansas, Kansas City, and colleagues. Currently, the United States Multi-Society Task Force on Colorectal Cancer advises colonoscopy intervals of 3 years for individuals with HRAs, 7-10 years for those with LRAs, and 10 years for those without adenomas.

“The evidence supporting these surveillance recommendations for clinically relevant endpoints such as cancer and cancer-related deaths among patients who undergo adenoma removal, particularly LRA, is minimal, because most of the evidence was based on the surrogate risk of metachronous advanced neoplasia,” the investigators wrote in Gastroenterology.

To provide more solid evidence, the investigators performed a systematic review and meta-analysis, ultimately analyzing 12 studies with data from 510,019 individuals at a mean age of 59.2 years. All studies reported rates of LRA, HRA, or no adenoma at baseline colonoscopy, plus incidence of metachronous CRC and/or CRC-related mortality. With these data, the investigators determined incidence of metachronous CRC and CRC-related mortality for each of the adenoma groups and also compared these incidences per 10,000 person-years of follow-up across groups.

After a mean follow-up of 8.5 years, patients with HRAs had a significantly higher rate of CRC compared with patients who had LRAs (13.81 vs. 4.5; odds ratio, 2.35; 95% confidence interval, 1.72-3.20) or no adenomas (13.81 vs. 3.4; OR, 2.92; 95% CI, 2.31-3.69). Similarly, but to a lesser degree, LRAs were associated with significantly greater risk of CRC than that of no adenomas (4.5 vs. 3.4; OR, 1.26; 95% CI, 1.06-1.51).

Data on CRC- related mortality further supported these minimal risk profiles because LRAs did not significantly increase the risk of CRC-related mortality compared with no adenomas (OR, 1.15; 95% CI, 0.76-1.74). In contrast, HRAs were associated with significantly greater risk of CRC-related death than that of both LRAs (OR, 2.48; 95% CI, 1.30-4.75) and no adenomas (OR, 2.69; 95% CI, 1.87-3.87).

The investigators acknowledged certain limitations of their study. For one, there were no randomized controlled trials in the meta-analysis, which can introduce bias. Loss of patients to follow-up is also possible; however, the investigators noted that there was a robust sample of patients available for study outcomes all the same. There is also risk of comparability bias in that HRA and LRA groups underwent more colonoscopies; however, the duration of follow-up and timing of last colonoscopy were similar among groups. Lastly, it’s possible the patient sample wasn’t representative because of healthy screenee bias, but the investigators compared groups against general population to minimize that bias.

The investigators also highlighted several strengths of their study that make their findings more reliable than those of past meta-analyses. For one, their study is the largest of its kind to date, and involved a significantly higher number of patients with LRA and no adenomas. Also, in contrast with previous studies, CRC and CRC-related mortality were evaluated rather than advanced adenomas, they noted.

“Furthermore, we also analyzed CRC incidence and mortality in the LRA group compared with the general population, with the [standardized incidence ratio] being lower and [standardized mortality ratio] being comparable, confirming that it is indeed a low-risk group,” they wrote.

Considering these strengths and the nature of their findings, Dr. Duvvuri and colleagues called for a more conservative approach to CRC surveillance among individuals with LRAs, and more research to investigate extending colonoscopy intervals even further.

“We recommend that the interval for follow-up colonoscopy should be the same in patients with LRAs or no adenomas but that the HRA group should have a more frequent surveillance interval for CRC surveillance compared with these groups,” they concluded. “Future studies should evaluate whether surveillance intervals could be lengthened beyond 10 years in the no-adenoma and LRA groups after an initial high-quality index colonoscopy.”

One author disclosed affiliations with Erbe, Cdx Labs, Aries, and others. Dr. Duvvuri and the remaining authors disclosed no conflicts.

Unlike high-risk adenomas (HRAs), low-risk adenomas (LRAs) have a minimal association with risk of metachronous colorectal cancer (CRC), and no relationship with odds of metachronous CRC-related mortality, according to a meta-analysis of more than 500,000 individuals.

These findings should impact surveillance guidelines and make follow-up the same for individuals with LRAs or no adenomas, reported lead author Abhiram Duvvuri, MD, of the division of gastroenterology and hepatology at the University of Kansas, Kansas City, and colleagues. Currently, the United States Multi-Society Task Force on Colorectal Cancer advises colonoscopy intervals of 3 years for individuals with HRAs, 7-10 years for those with LRAs, and 10 years for those without adenomas.

“The evidence supporting these surveillance recommendations for clinically relevant endpoints such as cancer and cancer-related deaths among patients who undergo adenoma removal, particularly LRA, is minimal, because most of the evidence was based on the surrogate risk of metachronous advanced neoplasia,” the investigators wrote in Gastroenterology.

To provide more solid evidence, the investigators performed a systematic review and meta-analysis, ultimately analyzing 12 studies with data from 510,019 individuals at a mean age of 59.2 years. All studies reported rates of LRA, HRA, or no adenoma at baseline colonoscopy, plus incidence of metachronous CRC and/or CRC-related mortality. With these data, the investigators determined incidence of metachronous CRC and CRC-related mortality for each of the adenoma groups and also compared these incidences per 10,000 person-years of follow-up across groups.

After a mean follow-up of 8.5 years, patients with HRAs had a significantly higher rate of CRC compared with patients who had LRAs (13.81 vs. 4.5; odds ratio, 2.35; 95% confidence interval, 1.72-3.20) or no adenomas (13.81 vs. 3.4; OR, 2.92; 95% CI, 2.31-3.69). Similarly, but to a lesser degree, LRAs were associated with significantly greater risk of CRC than that of no adenomas (4.5 vs. 3.4; OR, 1.26; 95% CI, 1.06-1.51).

Data on CRC- related mortality further supported these minimal risk profiles because LRAs did not significantly increase the risk of CRC-related mortality compared with no adenomas (OR, 1.15; 95% CI, 0.76-1.74). In contrast, HRAs were associated with significantly greater risk of CRC-related death than that of both LRAs (OR, 2.48; 95% CI, 1.30-4.75) and no adenomas (OR, 2.69; 95% CI, 1.87-3.87).

The investigators acknowledged certain limitations of their study. For one, there were no randomized controlled trials in the meta-analysis, which can introduce bias. Loss of patients to follow-up is also possible; however, the investigators noted that there was a robust sample of patients available for study outcomes all the same. There is also risk of comparability bias in that HRA and LRA groups underwent more colonoscopies; however, the duration of follow-up and timing of last colonoscopy were similar among groups. Lastly, it’s possible the patient sample wasn’t representative because of healthy screenee bias, but the investigators compared groups against general population to minimize that bias.

The investigators also highlighted several strengths of their study that make their findings more reliable than those of past meta-analyses. For one, their study is the largest of its kind to date, and involved a significantly higher number of patients with LRA and no adenomas. Also, in contrast with previous studies, CRC and CRC-related mortality were evaluated rather than advanced adenomas, they noted.

“Furthermore, we also analyzed CRC incidence and mortality in the LRA group compared with the general population, with the [standardized incidence ratio] being lower and [standardized mortality ratio] being comparable, confirming that it is indeed a low-risk group,” they wrote.

Considering these strengths and the nature of their findings, Dr. Duvvuri and colleagues called for a more conservative approach to CRC surveillance among individuals with LRAs, and more research to investigate extending colonoscopy intervals even further.

“We recommend that the interval for follow-up colonoscopy should be the same in patients with LRAs or no adenomas but that the HRA group should have a more frequent surveillance interval for CRC surveillance compared with these groups,” they concluded. “Future studies should evaluate whether surveillance intervals could be lengthened beyond 10 years in the no-adenoma and LRA groups after an initial high-quality index colonoscopy.”

One author disclosed affiliations with Erbe, Cdx Labs, Aries, and others. Dr. Duvvuri and the remaining authors disclosed no conflicts.

Unlike high-risk adenomas (HRAs), low-risk adenomas (LRAs) have a minimal association with risk of metachronous colorectal cancer (CRC), and no relationship with odds of metachronous CRC-related mortality, according to a meta-analysis of more than 500,000 individuals.

These findings should impact surveillance guidelines and make follow-up the same for individuals with LRAs or no adenomas, reported lead author Abhiram Duvvuri, MD, of the division of gastroenterology and hepatology at the University of Kansas, Kansas City, and colleagues. Currently, the United States Multi-Society Task Force on Colorectal Cancer advises colonoscopy intervals of 3 years for individuals with HRAs, 7-10 years for those with LRAs, and 10 years for those without adenomas.

“The evidence supporting these surveillance recommendations for clinically relevant endpoints such as cancer and cancer-related deaths among patients who undergo adenoma removal, particularly LRA, is minimal, because most of the evidence was based on the surrogate risk of metachronous advanced neoplasia,” the investigators wrote in Gastroenterology.

To provide more solid evidence, the investigators performed a systematic review and meta-analysis, ultimately analyzing 12 studies with data from 510,019 individuals at a mean age of 59.2 years. All studies reported rates of LRA, HRA, or no adenoma at baseline colonoscopy, plus incidence of metachronous CRC and/or CRC-related mortality. With these data, the investigators determined incidence of metachronous CRC and CRC-related mortality for each of the adenoma groups and also compared these incidences per 10,000 person-years of follow-up across groups.

After a mean follow-up of 8.5 years, patients with HRAs had a significantly higher rate of CRC compared with patients who had LRAs (13.81 vs. 4.5; odds ratio, 2.35; 95% confidence interval, 1.72-3.20) or no adenomas (13.81 vs. 3.4; OR, 2.92; 95% CI, 2.31-3.69). Similarly, but to a lesser degree, LRAs were associated with significantly greater risk of CRC than that of no adenomas (4.5 vs. 3.4; OR, 1.26; 95% CI, 1.06-1.51).

Data on CRC- related mortality further supported these minimal risk profiles because LRAs did not significantly increase the risk of CRC-related mortality compared with no adenomas (OR, 1.15; 95% CI, 0.76-1.74). In contrast, HRAs were associated with significantly greater risk of CRC-related death than that of both LRAs (OR, 2.48; 95% CI, 1.30-4.75) and no adenomas (OR, 2.69; 95% CI, 1.87-3.87).

The investigators acknowledged certain limitations of their study. For one, there were no randomized controlled trials in the meta-analysis, which can introduce bias. Loss of patients to follow-up is also possible; however, the investigators noted that there was a robust sample of patients available for study outcomes all the same. There is also risk of comparability bias in that HRA and LRA groups underwent more colonoscopies; however, the duration of follow-up and timing of last colonoscopy were similar among groups. Lastly, it’s possible the patient sample wasn’t representative because of healthy screenee bias, but the investigators compared groups against general population to minimize that bias.

The investigators also highlighted several strengths of their study that make their findings more reliable than those of past meta-analyses. For one, their study is the largest of its kind to date, and involved a significantly higher number of patients with LRA and no adenomas. Also, in contrast with previous studies, CRC and CRC-related mortality were evaluated rather than advanced adenomas, they noted.

“Furthermore, we also analyzed CRC incidence and mortality in the LRA group compared with the general population, with the [standardized incidence ratio] being lower and [standardized mortality ratio] being comparable, confirming that it is indeed a low-risk group,” they wrote.

Considering these strengths and the nature of their findings, Dr. Duvvuri and colleagues called for a more conservative approach to CRC surveillance among individuals with LRAs, and more research to investigate extending colonoscopy intervals even further.

“We recommend that the interval for follow-up colonoscopy should be the same in patients with LRAs or no adenomas but that the HRA group should have a more frequent surveillance interval for CRC surveillance compared with these groups,” they concluded. “Future studies should evaluate whether surveillance intervals could be lengthened beyond 10 years in the no-adenoma and LRA groups after an initial high-quality index colonoscopy.”

One author disclosed affiliations with Erbe, Cdx Labs, Aries, and others. Dr. Duvvuri and the remaining authors disclosed no conflicts.

There is no question that none of us, not just pediatricians, is doing a very good job of dealing with the obesity problem this nation faces. We can agree that a more active lifestyle that includes spells of vigorous activity is important for weight management. We know that in general overweight people sleep less than do those whose basal metabolic rate is normal. And, of course, we know that a diet high in calorie-dense foods is associated with unhealthy weight gain.

Not surprisingly, overweight individuals are usually struggling with all three of these challenges. They are less active, get too little sleep, and are ingesting a diet that is too calorie dense. In other words, they would benefit from a total lifestyle reboot. But you know as well as I do a change of that magnitude is much easier said than done. Few families can afford nor would they have the appetite for sending their children to a “fat camp” for 6 months with no guarantee of success.

Instead of throwing up our hands in the face of this monumental task or attacking it at close range, maybe we should aim our efforts at the risk associations that will yield the best results for our efforts. A group of researchers at the University of South Australia has just published a study in Pediatrics in which they provide some data that may help us target our interventions with obese and overweight children. The researchers did not investigate diet, but used accelerometers to determine how much time each child spent sleeping and a variety of activity levels. They then determined what effect changes in the child’s allocation of activity had on their adiposity.

The investigators found on a minute-to-minute basis that an increase in a child’s moderate-to-vigorous physical activity (MVPA) was up to six times more effective at influencing adiposity than was a decrease in sedentary time or an increase in sleep duration. For example, 17 minutes of MVPA had the same beneficial effect as 52 minutes more sleep or 56 minutes less sedentary time. Interestingly and somewhat surprisingly, the researchers found that light activity was positively associated with adiposity.

For those of us in primary care, this study from Australia suggests that our time (and the parents’ time) would be best spent figuring out how to include more MVPA in the child’s day and not focus so much on sleep duration and sedentary intervals.

However, before one can make any recommendation one must first have a clear understanding of how the child and his family spend the day. This process can be done in the office by interviewing the family. I have found that this is not as time consuming as one might think and often yields some valuable additional insight into the family’s dynamics. Sending the family home with an hourly log to be filled in or asking them to use a smartphone to record information will also work.

I must admit that at first I found the results of this study ran counter to my intuition. I have always felt that sleep is the linchpin to the solution of a variety of health style related problems. In my construct, more sleep has always been the first and easy answer and decreasing screen time the second. But, it turns out that increasing MVPA may give us the biggest bang for the buck. Which is fine with me.

The problem facing us is how we can be creative in adding that 20 minutes of vigorous activity. In most communities, we have allowed the school system to drop the ball. We can hope that this study will be confirmed or at least widely publicized. It feels like it is time to guarantee that every child gets a robust gym class every school day.
 

Dr. Wilkoff practiced primary care pediatrics in Brunswick, Maine for nearly 40 years. He has authored several books on behavioral pediatrics, including “How to Say No to Your Toddler.” Other than a Littman stethoscope he accepted as a first-year medical student in 1966, Dr. Wilkoff reports having nothing to disclose. Email him at [email protected].

There is no question that none of us, not just pediatricians, is doing a very good job of dealing with the obesity problem this nation faces. We can agree that a more active lifestyle that includes spells of vigorous activity is important for weight management. We know that in general overweight people sleep less than do those whose basal metabolic rate is normal. And, of course, we know that a diet high in calorie-dense foods is associated with unhealthy weight gain.

Not surprisingly, overweight individuals are usually struggling with all three of these challenges. They are less active, get too little sleep, and are ingesting a diet that is too calorie dense. In other words, they would benefit from a total lifestyle reboot. But you know as well as I do a change of that magnitude is much easier said than done. Few families can afford nor would they have the appetite for sending their children to a “fat camp” for 6 months with no guarantee of success.

Instead of throwing up our hands in the face of this monumental task or attacking it at close range, maybe we should aim our efforts at the risk associations that will yield the best results for our efforts. A group of researchers at the University of South Australia has just published a study in Pediatrics in which they provide some data that may help us target our interventions with obese and overweight children. The researchers did not investigate diet, but used accelerometers to determine how much time each child spent sleeping and a variety of activity levels. They then determined what effect changes in the child’s allocation of activity had on their adiposity.

The investigators found on a minute-to-minute basis that an increase in a child’s moderate-to-vigorous physical activity (MVPA) was up to six times more effective at influencing adiposity than was a decrease in sedentary time or an increase in sleep duration. For example, 17 minutes of MVPA had the same beneficial effect as 52 minutes more sleep or 56 minutes less sedentary time. Interestingly and somewhat surprisingly, the researchers found that light activity was positively associated with adiposity.

For those of us in primary care, this study from Australia suggests that our time (and the parents’ time) would be best spent figuring out how to include more MVPA in the child’s day and not focus so much on sleep duration and sedentary intervals.

However, before one can make any recommendation one must first have a clear understanding of how the child and his family spend the day. This process can be done in the office by interviewing the family. I have found that this is not as time consuming as one might think and often yields some valuable additional insight into the family’s dynamics. Sending the family home with an hourly log to be filled in or asking them to use a smartphone to record information will also work.

I must admit that at first I found the results of this study ran counter to my intuition. I have always felt that sleep is the linchpin to the solution of a variety of health style related problems. In my construct, more sleep has always been the first and easy answer and decreasing screen time the second. But, it turns out that increasing MVPA may give us the biggest bang for the buck. Which is fine with me.

The problem facing us is how we can be creative in adding that 20 minutes of vigorous activity. In most communities, we have allowed the school system to drop the ball. We can hope that this study will be confirmed or at least widely publicized. It feels like it is time to guarantee that every child gets a robust gym class every school day.
 

Dr. Wilkoff practiced primary care pediatrics in Brunswick, Maine for nearly 40 years. He has authored several books on behavioral pediatrics, including “How to Say No to Your Toddler.” Other than a Littman stethoscope he accepted as a first-year medical student in 1966, Dr. Wilkoff reports having nothing to disclose. Email him at [email protected].

There is no question that none of us, not just pediatricians, is doing a very good job of dealing with the obesity problem this nation faces. We can agree that a more active lifestyle that includes spells of vigorous activity is important for weight management. We know that in general overweight people sleep less than do those whose basal metabolic rate is normal. And, of course, we know that a diet high in calorie-dense foods is associated with unhealthy weight gain.

Not surprisingly, overweight individuals are usually struggling with all three of these challenges. They are less active, get too little sleep, and are ingesting a diet that is too calorie dense. In other words, they would benefit from a total lifestyle reboot. But you know as well as I do a change of that magnitude is much easier said than done. Few families can afford nor would they have the appetite for sending their children to a “fat camp” for 6 months with no guarantee of success.

Instead of throwing up our hands in the face of this monumental task or attacking it at close range, maybe we should aim our efforts at the risk associations that will yield the best results for our efforts. A group of researchers at the University of South Australia has just published a study in Pediatrics in which they provide some data that may help us target our interventions with obese and overweight children. The researchers did not investigate diet, but used accelerometers to determine how much time each child spent sleeping and a variety of activity levels. They then determined what effect changes in the child’s allocation of activity had on their adiposity.

The investigators found on a minute-to-minute basis that an increase in a child’s moderate-to-vigorous physical activity (MVPA) was up to six times more effective at influencing adiposity than was a decrease in sedentary time or an increase in sleep duration. For example, 17 minutes of MVPA had the same beneficial effect as 52 minutes more sleep or 56 minutes less sedentary time. Interestingly and somewhat surprisingly, the researchers found that light activity was positively associated with adiposity.

For those of us in primary care, this study from Australia suggests that our time (and the parents’ time) would be best spent figuring out how to include more MVPA in the child’s day and not focus so much on sleep duration and sedentary intervals.

However, before one can make any recommendation one must first have a clear understanding of how the child and his family spend the day. This process can be done in the office by interviewing the family. I have found that this is not as time consuming as one might think and often yields some valuable additional insight into the family’s dynamics. Sending the family home with an hourly log to be filled in or asking them to use a smartphone to record information will also work.

I must admit that at first I found the results of this study ran counter to my intuition. I have always felt that sleep is the linchpin to the solution of a variety of health style related problems. In my construct, more sleep has always been the first and easy answer and decreasing screen time the second. But, it turns out that increasing MVPA may give us the biggest bang for the buck. Which is fine with me.

The problem facing us is how we can be creative in adding that 20 minutes of vigorous activity. In most communities, we have allowed the school system to drop the ball. We can hope that this study will be confirmed or at least widely publicized. It feels like it is time to guarantee that every child gets a robust gym class every school day.
 

Dr. Wilkoff practiced primary care pediatrics in Brunswick, Maine for nearly 40 years. He has authored several books on behavioral pediatrics, including “How to Say No to Your Toddler.” Other than a Littman stethoscope he accepted as a first-year medical student in 1966, Dr. Wilkoff reports having nothing to disclose. Email him at [email protected].

Can you provide some background on endometriosis and the importance of early diagnosis?

Dr. Goldstein: Endometriosis is an inflammatory condition, characterized by endometrial tissue at sites outside the uterus—this definition comes from the World Endometriosis Society.

Endometriosis is said to affect about 10% of women of reproductive age, and if you look at a group, a subset of women with pelvic pain or infertility, the numbers rise to the range of 35% to 50%. It can present in a multitude of locations, mainly in the pelvis, although occasionally even in places like the lung. When it occurs in the uterus, it is known as adenomyosis; when it occurs inside the ovary, it can cause an endometrioma (or what is sometimes referred to as chocolate cyst of the ovary), but you can see endometriotic implants anywhere in the peritoneum—along the urinary tract, rectum, uterosacral ligaments, rectovaginal septum, and even the vaginal wall occasionally.

What I am really interested in is an earlier diagnosis of superficial endometriosis, and it should be apparent to the reader why this is important—the quality of life from pain from endometriosis can be debilitating. It can be a source of infertility, a source of menstrual irregularities, and a source of not only quality of life but also economic consequences. Many women can also undergo as much as a 7-year delay in diagnosis, so the need for a timely diagnosis and initiation of treatment is extremely important.

What is the role of ultrasound in endometriosis diagnostics?

Dr. Goldstein: In an article that I authored 31 years ago, I wrote that there was a difference between an ultrasound examination by referral and examining one’s patients with ultrasound. I coined a phrase: the “ultrasound-enhanced bimanual exam.” I believed that this term should become a routine part of the overall gynecologic exam. I wanted people to think about the bimanual that we had done for at least half a century, which, in my opinion, consists of 2 components:

1. An objective component: Is this uterus normal? Is it enlarged or irregular in contour, suggesting maybe fibroids? Is an ovary enlarged? If so, does it feel cystic or solid?
2. A subjective component: Does this patient have tenderness through the pelvis. Is there normal mobility of the pelvic organs?

Part of the thesis was that the objective portion could be replaced by an image that could be produced in seconds, dependent on the operator’s training and availability of equipment. The subjective portion, however, depended on the experience and, often, nuance of the examiner. Lately, I have been seeking to expand that thesis by having the imager use examination as part of their overall imaging—this is the concept of dynamic imaging.

Can you expand on the concept of dynamic ultrasound in this setting?

Dr. Goldstein: Presently, most imagers take a multitude of pictures, what I would call 2-dimensional snapshots, to illustrate anatomy. This is usually done by a sonographer, or a technician, who collects the images for viewing by the physician, who then often does so without holding the transducer. Increasing utilization of remote tools like teleradiology only makes this more likely, and for a minority of people who may use video clips instead of still images, they are still simply representations of anatomy. The guidelines for pelvic ultrasound are the underpinning of the expectation of those who are scanning the female pelvis. With dynamic imaging, the operator uses their other hand on the abdomen as well as some motion with the probe to see if they can elicit pain with the vaginal probe, checking for mobility, asking the patient to bear down. Whether you are a sonographer, a radiologist, or an ObGyn, dynamic imaging can bring the examination process into the imager’s hands.

Can you tell us more about the indications for pelvic sonography for endometriosis and what data can you give to support this?

Dr. Goldstein: There is a document titled “Ultrasound Examination of the Female Pelvis,” that was originally developed by the American Institute of Ultrasound in Medicine (AIUM). In this document, there are about 19 different indications for pelvic sonography (in no defined order), and it is interesting that the first indication listed is evaluation of pelvic pain. Well, I would ask you, how do you evaluate pelvic pain with a series of anatomic images? If you have a classic ovarian endometrioma, or you have a classic hydrosalpinx, you can surmise that these are the source of the pain that the patient is reporting. But how do you properly evaluate pain with just an anatomic image? Thus, the need to use dynamic assessment.

There was a concept first introduced by my colleague, Dr. Ilan Timor, known as the sliding organ sign, that was mainly used to determine if 2 structures were adherent or separate. This involved use of the abdominal hand, liberal use of the probe moving in and out, and under real-time vision, examining the patient with the ultrasound transducer; this is the concept of dynamic ultrasound. This practice can be expanded to verify if there is pelvic tenderness and can be a significant part of the nonlaparoscopic, presumptive diagnosis of endometriosis, even when there is no ovarian endometrioma.

To support this theory, I would point you toward a classic article by E Okaro and colleagues in the British Journal of OB-GYN. This study took 120 consecutive women with chronic pelvic pain who were scheduled for laparoscopy, but performed a transvaginal ultrasound prior, and they looked for anatomic abnormalities and divided this into hard markers and soft markers. Hard markers were obvious endometriomas and hydrosalpinges, while soft markers included things like reduced ovarian mobility, site-specific pelvic tenderness, and presence of loculated peritoneal fluid in the pelvis. These were typical of chronic pelvic pain patients that ranged from late teens to almost menopausal, as the average age was about 30 years old.

Patients had experienced pain for anywhere from 6 months to 12 years, but the average was about 4 years. At laparoscopy, 58% of these patients had pelvic pathology, and 42% had a normal pelvis. Of the 58% with pathology, the overwhelming majority—about 51 of 70 women—had endometriosis alone, and another 7 had endometriosis with adhesions. A normal ultrasound, based on the absence of hard markers, was found in 96 of 120 women. Thus, 24 of the 120 women had an abnormal scan based on the presence of these hard markers. At laparoscopy, all 24 women had abnormal laparoscopies. Of those 96 women who would have had a normal ultrasound, based on the anatomic absence of some pathology, 53% had an abnormal scan based on the presence of these soft markers while the remaining women had no soft- or hard-markers suggesting any pelvic pathology. At laparoscopy, 73% of the patients with soft markers had pelvic pathology and 27% had a normal laparoscopy. Of 45 patients who had a normal, transvaginal ultrasound, 9 were found to have small evidence of endometriosis without discrete endometriomas at laparoscopy.

To summarize the study data, 100% of patients with hard markers and chronic pelvic pain had abnormal anatomy at laparoscopy, but 73% of patients who had soft markers but otherwise would have been interpreted as normal anatomic findings had evidence of pelvic pathology. Such an approach, if used, could lead to a reduction in the number of unnecessary laparoscopies.

What it really boils down to is, if you have 100 women with chronic pelvic pain, are you willing to treat 100 patients without laparoscopy, knowing that 73 are going to have a positive laparoscopy and will require treatment anyway? You would treat 27% with a pharmaceutical agent that may provide relief of their pain, or may not, depending on what the true etiology was. I would be willing to do so, as a positive predictive value of 73% makes doing that worthwhile, and I believe a majority of clinicians would agree.

Do you have any other tips or ways to improve the reader’s understanding of transvaginal ultrasound?

Dr. Goldstein: Pelvic organs have mobility. If a premenopausal woman is examined in lithotomy position, if the ovaries are freely mobile, by gravity, they are going to go lateral to the uterus and are seen immediately adjacent to the iliac vessels. But remember, iliac vessels are retroperitoneal as they are outside the peritoneal cavity. If you were to turn that patient onto all fours, so that the ovaries are freely mobile, they are going to move somewhat toward the anterior abdominal wall. When an ovary is seen in a nonanatomic position, it could be normal or it could be held up by a loop of bowel, but it may indicate adhesions. This is where this sliding organ sign and liberal use of the other hand on the lower abdomen can be extremely important. The reader should also understand that our ability to localize ovaries on ultrasound depends on the amount of folliculogenesis. Follicles are black circles that are sonolucent, because they contain fluid, so they make it easy to localize ovaries, but also their anatomic position relative to the iliac vessels. However, there is a caveat—which is, sometimes an ovary might look like it is behind the uterus and not in its normal anatomic location. When dynamic imaging is used, you are able to cajole that ovary to move lateral and sit on top of the iliac vessels, which can enable you make the proper diagnosis.

Can you provide some background on endometriosis and the importance of early diagnosis?

Dr. Goldstein: Endometriosis is an inflammatory condition, characterized by endometrial tissue at sites outside the uterus—this definition comes from the World Endometriosis Society.

Endometriosis is said to affect about 10% of women of reproductive age, and if you look at a group, a subset of women with pelvic pain or infertility, the numbers rise to the range of 35% to 50%. It can present in a multitude of locations, mainly in the pelvis, although occasionally even in places like the lung. When it occurs in the uterus, it is known as adenomyosis; when it occurs inside the ovary, it can cause an endometrioma (or what is sometimes referred to as chocolate cyst of the ovary), but you can see endometriotic implants anywhere in the peritoneum—along the urinary tract, rectum, uterosacral ligaments, rectovaginal septum, and even the vaginal wall occasionally.

What I am really interested in is an earlier diagnosis of superficial endometriosis, and it should be apparent to the reader why this is important—the quality of life from pain from endometriosis can be debilitating. It can be a source of infertility, a source of menstrual irregularities, and a source of not only quality of life but also economic consequences. Many women can also undergo as much as a 7-year delay in diagnosis, so the need for a timely diagnosis and initiation of treatment is extremely important.

What is the role of ultrasound in endometriosis diagnostics?

Dr. Goldstein: In an article that I authored 31 years ago, I wrote that there was a difference between an ultrasound examination by referral and examining one’s patients with ultrasound. I coined a phrase: the “ultrasound-enhanced bimanual exam.” I believed that this term should become a routine part of the overall gynecologic exam. I wanted people to think about the bimanual that we had done for at least half a century, which, in my opinion, consists of 2 components:

1. An objective component: Is this uterus normal? Is it enlarged or irregular in contour, suggesting maybe fibroids? Is an ovary enlarged? If so, does it feel cystic or solid?
2. A subjective component: Does this patient have tenderness through the pelvis. Is there normal mobility of the pelvic organs?

Part of the thesis was that the objective portion could be replaced by an image that could be produced in seconds, dependent on the operator’s training and availability of equipment. The subjective portion, however, depended on the experience and, often, nuance of the examiner. Lately, I have been seeking to expand that thesis by having the imager use examination as part of their overall imaging—this is the concept of dynamic imaging.

Can you expand on the concept of dynamic ultrasound in this setting?

Dr. Goldstein: Presently, most imagers take a multitude of pictures, what I would call 2-dimensional snapshots, to illustrate anatomy. This is usually done by a sonographer, or a technician, who collects the images for viewing by the physician, who then often does so without holding the transducer. Increasing utilization of remote tools like teleradiology only makes this more likely, and for a minority of people who may use video clips instead of still images, they are still simply representations of anatomy. The guidelines for pelvic ultrasound are the underpinning of the expectation of those who are scanning the female pelvis. With dynamic imaging, the operator uses their other hand on the abdomen as well as some motion with the probe to see if they can elicit pain with the vaginal probe, checking for mobility, asking the patient to bear down. Whether you are a sonographer, a radiologist, or an ObGyn, dynamic imaging can bring the examination process into the imager’s hands.

Can you tell us more about the indications for pelvic sonography for endometriosis and what data can you give to support this?

Dr. Goldstein: There is a document titled “Ultrasound Examination of the Female Pelvis,” that was originally developed by the American Institute of Ultrasound in Medicine (AIUM). In this document, there are about 19 different indications for pelvic sonography (in no defined order), and it is interesting that the first indication listed is evaluation of pelvic pain. Well, I would ask you, how do you evaluate pelvic pain with a series of anatomic images? If you have a classic ovarian endometrioma, or you have a classic hydrosalpinx, you can surmise that these are the source of the pain that the patient is reporting. But how do you properly evaluate pain with just an anatomic image? Thus, the need to use dynamic assessment.

There was a concept first introduced by my colleague, Dr. Ilan Timor, known as the sliding organ sign, that was mainly used to determine if 2 structures were adherent or separate. This involved use of the abdominal hand, liberal use of the probe moving in and out, and under real-time vision, examining the patient with the ultrasound transducer; this is the concept of dynamic ultrasound. This practice can be expanded to verify if there is pelvic tenderness and can be a significant part of the nonlaparoscopic, presumptive diagnosis of endometriosis, even when there is no ovarian endometrioma.

To support this theory, I would point you toward a classic article by E Okaro and colleagues in the British Journal of OB-GYN. This study took 120 consecutive women with chronic pelvic pain who were scheduled for laparoscopy, but performed a transvaginal ultrasound prior, and they looked for anatomic abnormalities and divided this into hard markers and soft markers. Hard markers were obvious endometriomas and hydrosalpinges, while soft markers included things like reduced ovarian mobility, site-specific pelvic tenderness, and presence of loculated peritoneal fluid in the pelvis. These were typical of chronic pelvic pain patients that ranged from late teens to almost menopausal, as the average age was about 30 years old.

Patients had experienced pain for anywhere from 6 months to 12 years, but the average was about 4 years. At laparoscopy, 58% of these patients had pelvic pathology, and 42% had a normal pelvis. Of the 58% with pathology, the overwhelming majority—about 51 of 70 women—had endometriosis alone, and another 7 had endometriosis with adhesions. A normal ultrasound, based on the absence of hard markers, was found in 96 of 120 women. Thus, 24 of the 120 women had an abnormal scan based on the presence of these hard markers. At laparoscopy, all 24 women had abnormal laparoscopies. Of those 96 women who would have had a normal ultrasound, based on the anatomic absence of some pathology, 53% had an abnormal scan based on the presence of these soft markers while the remaining women had no soft- or hard-markers suggesting any pelvic pathology. At laparoscopy, 73% of the patients with soft markers had pelvic pathology and 27% had a normal laparoscopy. Of 45 patients who had a normal, transvaginal ultrasound, 9 were found to have small evidence of endometriosis without discrete endometriomas at laparoscopy.

To summarize the study data, 100% of patients with hard markers and chronic pelvic pain had abnormal anatomy at laparoscopy, but 73% of patients who had soft markers but otherwise would have been interpreted as normal anatomic findings had evidence of pelvic pathology. Such an approach, if used, could lead to a reduction in the number of unnecessary laparoscopies.

What it really boils down to is, if you have 100 women with chronic pelvic pain, are you willing to treat 100 patients without laparoscopy, knowing that 73 are going to have a positive laparoscopy and will require treatment anyway? You would treat 27% with a pharmaceutical agent that may provide relief of their pain, or may not, depending on what the true etiology was. I would be willing to do so, as a positive predictive value of 73% makes doing that worthwhile, and I believe a majority of clinicians would agree.

Do you have any other tips or ways to improve the reader’s understanding of transvaginal ultrasound?

Dr. Goldstein: Pelvic organs have mobility. If a premenopausal woman is examined in lithotomy position, if the ovaries are freely mobile, by gravity, they are going to go lateral to the uterus and are seen immediately adjacent to the iliac vessels. But remember, iliac vessels are retroperitoneal as they are outside the peritoneal cavity. If you were to turn that patient onto all fours, so that the ovaries are freely mobile, they are going to move somewhat toward the anterior abdominal wall. When an ovary is seen in a nonanatomic position, it could be normal or it could be held up by a loop of bowel, but it may indicate adhesions. This is where this sliding organ sign and liberal use of the other hand on the lower abdomen can be extremely important. The reader should also understand that our ability to localize ovaries on ultrasound depends on the amount of folliculogenesis. Follicles are black circles that are sonolucent, because they contain fluid, so they make it easy to localize ovaries, but also their anatomic position relative to the iliac vessels. However, there is a caveat—which is, sometimes an ovary might look like it is behind the uterus and not in its normal anatomic location. When dynamic imaging is used, you are able to cajole that ovary to move lateral and sit on top of the iliac vessels, which can enable you make the proper diagnosis.

Can you provide some background on endometriosis and the importance of early diagnosis?

Dr. Goldstein: Endometriosis is an inflammatory condition, characterized by endometrial tissue at sites outside the uterus—this definition comes from the World Endometriosis Society.

Endometriosis is said to affect about 10% of women of reproductive age, and if you look at a group, a subset of women with pelvic pain or infertility, the numbers rise to the range of 35% to 50%. It can present in a multitude of locations, mainly in the pelvis, although occasionally even in places like the lung. When it occurs in the uterus, it is known as adenomyosis; when it occurs inside the ovary, it can cause an endometrioma (or what is sometimes referred to as chocolate cyst of the ovary), but you can see endometriotic implants anywhere in the peritoneum—along the urinary tract, rectum, uterosacral ligaments, rectovaginal septum, and even the vaginal wall occasionally.

What I am really interested in is an earlier diagnosis of superficial endometriosis, and it should be apparent to the reader why this is important—the quality of life from pain from endometriosis can be debilitating. It can be a source of infertility, a source of menstrual irregularities, and a source of not only quality of life but also economic consequences. Many women can also undergo as much as a 7-year delay in diagnosis, so the need for a timely diagnosis and initiation of treatment is extremely important.

What is the role of ultrasound in endometriosis diagnostics?

Dr. Goldstein: In an article that I authored 31 years ago, I wrote that there was a difference between an ultrasound examination by referral and examining one’s patients with ultrasound. I coined a phrase: the “ultrasound-enhanced bimanual exam.” I believed that this term should become a routine part of the overall gynecologic exam. I wanted people to think about the bimanual that we had done for at least half a century, which, in my opinion, consists of 2 components:

1. An objective component: Is this uterus normal? Is it enlarged or irregular in contour, suggesting maybe fibroids? Is an ovary enlarged? If so, does it feel cystic or solid?
2. A subjective component: Does this patient have tenderness through the pelvis. Is there normal mobility of the pelvic organs?

Part of the thesis was that the objective portion could be replaced by an image that could be produced in seconds, dependent on the operator’s training and availability of equipment. The subjective portion, however, depended on the experience and, often, nuance of the examiner. Lately, I have been seeking to expand that thesis by having the imager use examination as part of their overall imaging—this is the concept of dynamic imaging.

Can you expand on the concept of dynamic ultrasound in this setting?

Dr. Goldstein: Presently, most imagers take a multitude of pictures, what I would call 2-dimensional snapshots, to illustrate anatomy. This is usually done by a sonographer, or a technician, who collects the images for viewing by the physician, who then often does so without holding the transducer. Increasing utilization of remote tools like teleradiology only makes this more likely, and for a minority of people who may use video clips instead of still images, they are still simply representations of anatomy. The guidelines for pelvic ultrasound are the underpinning of the expectation of those who are scanning the female pelvis. With dynamic imaging, the operator uses their other hand on the abdomen as well as some motion with the probe to see if they can elicit pain with the vaginal probe, checking for mobility, asking the patient to bear down. Whether you are a sonographer, a radiologist, or an ObGyn, dynamic imaging can bring the examination process into the imager’s hands.

Can you tell us more about the indications for pelvic sonography for endometriosis and what data can you give to support this?

Dr. Goldstein: There is a document titled “Ultrasound Examination of the Female Pelvis,” that was originally developed by the American Institute of Ultrasound in Medicine (AIUM). In this document, there are about 19 different indications for pelvic sonography (in no defined order), and it is interesting that the first indication listed is evaluation of pelvic pain. Well, I would ask you, how do you evaluate pelvic pain with a series of anatomic images? If you have a classic ovarian endometrioma, or you have a classic hydrosalpinx, you can surmise that these are the source of the pain that the patient is reporting. But how do you properly evaluate pain with just an anatomic image? Thus, the need to use dynamic assessment.

There was a concept first introduced by my colleague, Dr. Ilan Timor, known as the sliding organ sign, that was mainly used to determine if 2 structures were adherent or separate. This involved use of the abdominal hand, liberal use of the probe moving in and out, and under real-time vision, examining the patient with the ultrasound transducer; this is the concept of dynamic ultrasound. This practice can be expanded to verify if there is pelvic tenderness and can be a significant part of the nonlaparoscopic, presumptive diagnosis of endometriosis, even when there is no ovarian endometrioma.

To support this theory, I would point you toward a classic article by E Okaro and colleagues in the British Journal of OB-GYN. This study took 120 consecutive women with chronic pelvic pain who were scheduled for laparoscopy, but performed a transvaginal ultrasound prior, and they looked for anatomic abnormalities and divided this into hard markers and soft markers. Hard markers were obvious endometriomas and hydrosalpinges, while soft markers included things like reduced ovarian mobility, site-specific pelvic tenderness, and presence of loculated peritoneal fluid in the pelvis. These were typical of chronic pelvic pain patients that ranged from late teens to almost menopausal, as the average age was about 30 years old.

Patients had experienced pain for anywhere from 6 months to 12 years, but the average was about 4 years. At laparoscopy, 58% of these patients had pelvic pathology, and 42% had a normal pelvis. Of the 58% with pathology, the overwhelming majority—about 51 of 70 women—had endometriosis alone, and another 7 had endometriosis with adhesions. A normal ultrasound, based on the absence of hard markers, was found in 96 of 120 women. Thus, 24 of the 120 women had an abnormal scan based on the presence of these hard markers. At laparoscopy, all 24 women had abnormal laparoscopies. Of those 96 women who would have had a normal ultrasound, based on the anatomic absence of some pathology, 53% had an abnormal scan based on the presence of these soft markers while the remaining women had no soft- or hard-markers suggesting any pelvic pathology. At laparoscopy, 73% of the patients with soft markers had pelvic pathology and 27% had a normal laparoscopy. Of 45 patients who had a normal, transvaginal ultrasound, 9 were found to have small evidence of endometriosis without discrete endometriomas at laparoscopy.

To summarize the study data, 100% of patients with hard markers and chronic pelvic pain had abnormal anatomy at laparoscopy, but 73% of patients who had soft markers but otherwise would have been interpreted as normal anatomic findings had evidence of pelvic pathology. Such an approach, if used, could lead to a reduction in the number of unnecessary laparoscopies.

What it really boils down to is, if you have 100 women with chronic pelvic pain, are you willing to treat 100 patients without laparoscopy, knowing that 73 are going to have a positive laparoscopy and will require treatment anyway? You would treat 27% with a pharmaceutical agent that may provide relief of their pain, or may not, depending on what the true etiology was. I would be willing to do so, as a positive predictive value of 73% makes doing that worthwhile, and I believe a majority of clinicians would agree.

Do you have any other tips or ways to improve the reader’s understanding of transvaginal ultrasound?

Dr. Goldstein: Pelvic organs have mobility. If a premenopausal woman is examined in lithotomy position, if the ovaries are freely mobile, by gravity, they are going to go lateral to the uterus and are seen immediately adjacent to the iliac vessels. But remember, iliac vessels are retroperitoneal as they are outside the peritoneal cavity. If you were to turn that patient onto all fours, so that the ovaries are freely mobile, they are going to move somewhat toward the anterior abdominal wall. When an ovary is seen in a nonanatomic position, it could be normal or it could be held up by a loop of bowel, but it may indicate adhesions. This is where this sliding organ sign and liberal use of the other hand on the lower abdomen can be extremely important. The reader should also understand that our ability to localize ovaries on ultrasound depends on the amount of folliculogenesis. Follicles are black circles that are sonolucent, because they contain fluid, so they make it easy to localize ovaries, but also their anatomic position relative to the iliac vessels. However, there is a caveat—which is, sometimes an ovary might look like it is behind the uterus and not in its normal anatomic location. When dynamic imaging is used, you are able to cajole that ovary to move lateral and sit on top of the iliac vessels, which can enable you make the proper diagnosis.

THE CASE

A 37-year-old man with a history of asthma, schizoaffective disorder, and tobacco use (36 packs per year) presented to the clinic after 5 days of worsening cough, reproducible left-sided chest pain, and increasing shortness of breath. He also experienced chills, fatigue, nausea, and vomiting but was afebrile. The patient had not travelled recently nor had direct contact with anyone sick. He also denied intravenous (IV) drug use, alcohol use, and bloody sputum. Recently, he had intentionally lost weight, as recommended by his psychiatrist.

Medication review revealed that he was taking many central-acting agents for schizoaffective disorder, including alprazolam, aripiprazole, desvenlafaxine, and quetiapine. Due to his intermittent asthma since childhood, he used an albuterol inhaler as needed, which currently offered only minimal relief. He denied any history of hospitalization or intubation for asthma.

During the clinic visit, his blood pressure was 90/60 mm Hg and his heart rate was normal. His pulse oximetry was 92% on room air. On physical examination, he had normal-appearing dentition. Auscultation revealed bilateral expiratory wheezes with decreased breath sounds at the left lower lobe.

A plain chest radiograph (CXR) performed in the clinic (FIGURE 1) showed a large, thick-walled cavitary lesion with an air-fluid level in the left lower lobe. The patient was directly admitted to the Family Medicine Inpatient Service. Computed tomography (CT) of the chest with contrast was ordered to rule out empyema or malignancy. The chest CT confirmed the previous findings while also revealing a surrounding satellite nodularity in the left lower lobe (FIGURE 2). QuantiFERON-TB Gold and HIV tests were both negative.

THE DIAGNOSIS

The patient was given a diagnosis of a lung abscess based on symptoms and imaging. An extensive smoking history, as well as multiple sedating medications, increased his likelihood of aspiration.

DISCUSSION

Lung abscess is the probable diagnosis in a patient with indolent infectious symptoms (cough, fever, night sweats) developing over days to weeks and a CXR finding of pulmonary opacity, often with an air-fluid level.^1-4 A lung abscess is a circumscribed collection of pus in the lung parenchyma that develops as a result of microbial infection.⁴

Primary vs secondary abscess. Lung abscesses can be divided into 2 groups: primary and secondary abscesses. Primary abscesses (60%) occur without any other medical condition or in patients prone to aspiration.⁵ Secondary abscesses occur in the setting of a comorbid medical condition, such as lung disease, heart disease, bronchogenic neoplasm, or immunocompromised status.⁵

Continue to: With a primary lung abscess...

With a primary lung abscess, oropharyngeal contents are aspirated (generally while the patient is unconscious) and contain mixed flora.² The aspirate typically migrates to the posterior segments of the upper lobes and to the superior segments of the lower lobes. These abscesses are usually singular and have an air-fluid level.^1,2

Secondary lung abscesses occur in bronchial obstruction (by tumor, foreign body, or enlarged lymph nodes), with coexisting lung diseases (bronchiectasis, cystic fibrosis, infected pulmonary infarcts, lung contusion) or by direct spread (broncho-esophageal fistula, subphrenic abscess).⁶ Secondary abscesses are associated with a poorer prognosis, dependent on the patient’s general condition and underlying disease.⁷

What to rule out

The differential diagnosis of cavitary lung lesion includes tuberculosis, necrotizing pneumonia, bronchial carcinoma, pulmonary embolism, vasculitis (eg, Churg-Strauss syndrome), and localized pleural empyema.^1,4 A CT scan is helpful to differentiate between a parenchymal lesion and pleural collection, which may not be as clear on CXR.^1,4

Tuberculosis manifests with fatigue, weight loss, and night sweats; a chest CT will reveal a cavitating lesion (usually upper lobe) with a characteristic “rim sign” that includes caseous necrosis surrounded by a peripheral enhancing rim.⁸

Necrotizing pneumonia manifests as acute, fulminant infection. The most common causative organisms on sputum culture are Streptococcus pneumoniae, Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas species. Plain radiography will reveal multiple cavities and often associated pleural effusion and empyema.⁹

Continue to: Excavating bronchogenic carcinomas

Excavating bronchogenic carcinomas differ from a lung abscess in that a patient with the latter is typically, but not always, febrile and has purulent sputum. On imaging, a bronchogenic carcinoma has a thicker and more irregular wall than a lung abscess.¹⁰

Treatment

When antibiotics first became available, penicillin was used to treat lung abscess.¹¹ Then IV clindamycin became the drug of choice after 2 trials demonstrated its superiority to IV penicillin.^12,13 More recently, clindamycin alone has fallen out of favor due to growing anaerobic resistance.¹⁴

Current therapy includes beta-lactam with beta-lactamase inhibitors.¹⁴ Lung abscesses are typically polymicrobial and thus carry different degrees of antibiotic resistance.^15,16 If culture data are available, targeted therapy is preferred, especially for secondary abscesses.⁷ Antibiotic therapy is usually continued until a CXR reveals a small lesion or is clear, which may require several months of outpatient oral antibiotic therapy.⁴

Our patient was treated with IV clindamycin for 3 days in the hospital. Clindamycin was chosen due to his penicillin allergy and started empirically without any culture data. He was transitioned to oral clindamycin and completed a total 3-week course as his CXR continued to show improvement (FIGURE 3). He did not undergo bronchoscopy. A follow-up CXR showed resolution of lung abscess at 9 months. (FIGURE 4).

THE TAKEAWAY

All patients with lung abscesses should have sputum culture with gram stain done—­ideally prior to starting antibiotics.^3,4 Bronchoscopy should be considered for patients with atypical presentations or those who fail standard therapy, but may be used in other cases, as well.³

CORRESPONDENCE
Morteza Khodaee, MD, MPH, AFW Clinic, 3055 Roslyn Street, Denver, CO 80238; [email protected]

THE CASE

A 37-year-old man with a history of asthma, schizoaffective disorder, and tobacco use (36 packs per year) presented to the clinic after 5 days of worsening cough, reproducible left-sided chest pain, and increasing shortness of breath. He also experienced chills, fatigue, nausea, and vomiting but was afebrile. The patient had not travelled recently nor had direct contact with anyone sick. He also denied intravenous (IV) drug use, alcohol use, and bloody sputum. Recently, he had intentionally lost weight, as recommended by his psychiatrist.

Medication review revealed that he was taking many central-acting agents for schizoaffective disorder, including alprazolam, aripiprazole, desvenlafaxine, and quetiapine. Due to his intermittent asthma since childhood, he used an albuterol inhaler as needed, which currently offered only minimal relief. He denied any history of hospitalization or intubation for asthma.

During the clinic visit, his blood pressure was 90/60 mm Hg and his heart rate was normal. His pulse oximetry was 92% on room air. On physical examination, he had normal-appearing dentition. Auscultation revealed bilateral expiratory wheezes with decreased breath sounds at the left lower lobe.

A plain chest radiograph (CXR) performed in the clinic (FIGURE 1) showed a large, thick-walled cavitary lesion with an air-fluid level in the left lower lobe. The patient was directly admitted to the Family Medicine Inpatient Service. Computed tomography (CT) of the chest with contrast was ordered to rule out empyema or malignancy. The chest CT confirmed the previous findings while also revealing a surrounding satellite nodularity in the left lower lobe (FIGURE 2). QuantiFERON-TB Gold and HIV tests were both negative.

THE DIAGNOSIS

The patient was given a diagnosis of a lung abscess based on symptoms and imaging. An extensive smoking history, as well as multiple sedating medications, increased his likelihood of aspiration.

DISCUSSION

Lung abscess is the probable diagnosis in a patient with indolent infectious symptoms (cough, fever, night sweats) developing over days to weeks and a CXR finding of pulmonary opacity, often with an air-fluid level.^1-4 A lung abscess is a circumscribed collection of pus in the lung parenchyma that develops as a result of microbial infection.⁴

Primary vs secondary abscess. Lung abscesses can be divided into 2 groups: primary and secondary abscesses. Primary abscesses (60%) occur without any other medical condition or in patients prone to aspiration.⁵ Secondary abscesses occur in the setting of a comorbid medical condition, such as lung disease, heart disease, bronchogenic neoplasm, or immunocompromised status.⁵

Continue to: With a primary lung abscess...

With a primary lung abscess, oropharyngeal contents are aspirated (generally while the patient is unconscious) and contain mixed flora.² The aspirate typically migrates to the posterior segments of the upper lobes and to the superior segments of the lower lobes. These abscesses are usually singular and have an air-fluid level.^1,2

Secondary lung abscesses occur in bronchial obstruction (by tumor, foreign body, or enlarged lymph nodes), with coexisting lung diseases (bronchiectasis, cystic fibrosis, infected pulmonary infarcts, lung contusion) or by direct spread (broncho-esophageal fistula, subphrenic abscess).⁶ Secondary abscesses are associated with a poorer prognosis, dependent on the patient’s general condition and underlying disease.⁷

What to rule out

The differential diagnosis of cavitary lung lesion includes tuberculosis, necrotizing pneumonia, bronchial carcinoma, pulmonary embolism, vasculitis (eg, Churg-Strauss syndrome), and localized pleural empyema.^1,4 A CT scan is helpful to differentiate between a parenchymal lesion and pleural collection, which may not be as clear on CXR.^1,4

Tuberculosis manifests with fatigue, weight loss, and night sweats; a chest CT will reveal a cavitating lesion (usually upper lobe) with a characteristic “rim sign” that includes caseous necrosis surrounded by a peripheral enhancing rim.⁸

Necrotizing pneumonia manifests as acute, fulminant infection. The most common causative organisms on sputum culture are Streptococcus pneumoniae, Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas species. Plain radiography will reveal multiple cavities and often associated pleural effusion and empyema.⁹

Continue to: Excavating bronchogenic carcinomas

Excavating bronchogenic carcinomas differ from a lung abscess in that a patient with the latter is typically, but not always, febrile and has purulent sputum. On imaging, a bronchogenic carcinoma has a thicker and more irregular wall than a lung abscess.¹⁰

Treatment

When antibiotics first became available, penicillin was used to treat lung abscess.¹¹ Then IV clindamycin became the drug of choice after 2 trials demonstrated its superiority to IV penicillin.^12,13 More recently, clindamycin alone has fallen out of favor due to growing anaerobic resistance.¹⁴

Current therapy includes beta-lactam with beta-lactamase inhibitors.¹⁴ Lung abscesses are typically polymicrobial and thus carry different degrees of antibiotic resistance.^15,16 If culture data are available, targeted therapy is preferred, especially for secondary abscesses.⁷ Antibiotic therapy is usually continued until a CXR reveals a small lesion or is clear, which may require several months of outpatient oral antibiotic therapy.⁴

Our patient was treated with IV clindamycin for 3 days in the hospital. Clindamycin was chosen due to his penicillin allergy and started empirically without any culture data. He was transitioned to oral clindamycin and completed a total 3-week course as his CXR continued to show improvement (FIGURE 3). He did not undergo bronchoscopy. A follow-up CXR showed resolution of lung abscess at 9 months. (FIGURE 4).

THE TAKEAWAY

All patients with lung abscesses should have sputum culture with gram stain done—­ideally prior to starting antibiotics.^3,4 Bronchoscopy should be considered for patients with atypical presentations or those who fail standard therapy, but may be used in other cases, as well.³

CORRESPONDENCE
Morteza Khodaee, MD, MPH, AFW Clinic, 3055 Roslyn Street, Denver, CO 80238; [email protected]

THE CASE

A 37-year-old man with a history of asthma, schizoaffective disorder, and tobacco use (36 packs per year) presented to the clinic after 5 days of worsening cough, reproducible left-sided chest pain, and increasing shortness of breath. He also experienced chills, fatigue, nausea, and vomiting but was afebrile. The patient had not travelled recently nor had direct contact with anyone sick. He also denied intravenous (IV) drug use, alcohol use, and bloody sputum. Recently, he had intentionally lost weight, as recommended by his psychiatrist.

Medication review revealed that he was taking many central-acting agents for schizoaffective disorder, including alprazolam, aripiprazole, desvenlafaxine, and quetiapine. Due to his intermittent asthma since childhood, he used an albuterol inhaler as needed, which currently offered only minimal relief. He denied any history of hospitalization or intubation for asthma.

During the clinic visit, his blood pressure was 90/60 mm Hg and his heart rate was normal. His pulse oximetry was 92% on room air. On physical examination, he had normal-appearing dentition. Auscultation revealed bilateral expiratory wheezes with decreased breath sounds at the left lower lobe.

A plain chest radiograph (CXR) performed in the clinic (FIGURE 1) showed a large, thick-walled cavitary lesion with an air-fluid level in the left lower lobe. The patient was directly admitted to the Family Medicine Inpatient Service. Computed tomography (CT) of the chest with contrast was ordered to rule out empyema or malignancy. The chest CT confirmed the previous findings while also revealing a surrounding satellite nodularity in the left lower lobe (FIGURE 2). QuantiFERON-TB Gold and HIV tests were both negative.

THE DIAGNOSIS

The patient was given a diagnosis of a lung abscess based on symptoms and imaging. An extensive smoking history, as well as multiple sedating medications, increased his likelihood of aspiration.

DISCUSSION

Lung abscess is the probable diagnosis in a patient with indolent infectious symptoms (cough, fever, night sweats) developing over days to weeks and a CXR finding of pulmonary opacity, often with an air-fluid level.^1-4 A lung abscess is a circumscribed collection of pus in the lung parenchyma that develops as a result of microbial infection.⁴

Primary vs secondary abscess. Lung abscesses can be divided into 2 groups: primary and secondary abscesses. Primary abscesses (60%) occur without any other medical condition or in patients prone to aspiration.⁵ Secondary abscesses occur in the setting of a comorbid medical condition, such as lung disease, heart disease, bronchogenic neoplasm, or immunocompromised status.⁵

Continue to: With a primary lung abscess...

With a primary lung abscess, oropharyngeal contents are aspirated (generally while the patient is unconscious) and contain mixed flora.² The aspirate typically migrates to the posterior segments of the upper lobes and to the superior segments of the lower lobes. These abscesses are usually singular and have an air-fluid level.^1,2

Secondary lung abscesses occur in bronchial obstruction (by tumor, foreign body, or enlarged lymph nodes), with coexisting lung diseases (bronchiectasis, cystic fibrosis, infected pulmonary infarcts, lung contusion) or by direct spread (broncho-esophageal fistula, subphrenic abscess).⁶ Secondary abscesses are associated with a poorer prognosis, dependent on the patient’s general condition and underlying disease.⁷

What to rule out

The differential diagnosis of cavitary lung lesion includes tuberculosis, necrotizing pneumonia, bronchial carcinoma, pulmonary embolism, vasculitis (eg, Churg-Strauss syndrome), and localized pleural empyema.^1,4 A CT scan is helpful to differentiate between a parenchymal lesion and pleural collection, which may not be as clear on CXR.^1,4

Tuberculosis manifests with fatigue, weight loss, and night sweats; a chest CT will reveal a cavitating lesion (usually upper lobe) with a characteristic “rim sign” that includes caseous necrosis surrounded by a peripheral enhancing rim.⁸

Necrotizing pneumonia manifests as acute, fulminant infection. The most common causative organisms on sputum culture are Streptococcus pneumoniae, Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas species. Plain radiography will reveal multiple cavities and often associated pleural effusion and empyema.⁹

Continue to: Excavating bronchogenic carcinomas

Excavating bronchogenic carcinomas differ from a lung abscess in that a patient with the latter is typically, but not always, febrile and has purulent sputum. On imaging, a bronchogenic carcinoma has a thicker and more irregular wall than a lung abscess.¹⁰

Treatment

When antibiotics first became available, penicillin was used to treat lung abscess.¹¹ Then IV clindamycin became the drug of choice after 2 trials demonstrated its superiority to IV penicillin.^12,13 More recently, clindamycin alone has fallen out of favor due to growing anaerobic resistance.¹⁴

Current therapy includes beta-lactam with beta-lactamase inhibitors.¹⁴ Lung abscesses are typically polymicrobial and thus carry different degrees of antibiotic resistance.^15,16 If culture data are available, targeted therapy is preferred, especially for secondary abscesses.⁷ Antibiotic therapy is usually continued until a CXR reveals a small lesion or is clear, which may require several months of outpatient oral antibiotic therapy.⁴

Our patient was treated with IV clindamycin for 3 days in the hospital. Clindamycin was chosen due to his penicillin allergy and started empirically without any culture data. He was transitioned to oral clindamycin and completed a total 3-week course as his CXR continued to show improvement (FIGURE 3). He did not undergo bronchoscopy. A follow-up CXR showed resolution of lung abscess at 9 months. (FIGURE 4).

THE TAKEAWAY

All patients with lung abscesses should have sputum culture with gram stain done—­ideally prior to starting antibiotics.^3,4 Bronchoscopy should be considered for patients with atypical presentations or those who fail standard therapy, but may be used in other cases, as well.³

CORRESPONDENCE
Morteza Khodaee, MD, MPH, AFW Clinic, 3055 Roslyn Street, Denver, CO 80238; [email protected]