Morolake Amole, MD

Insulin pump technology has been available since the 1970s. Innovation in insulin pumps has had significant impact on the management of diabetes mellitus (DM). In recent years, automated insulin pump technology (AIP) has proven to be a safe and effective way to treat DM. It has been studied mostly in highly organized randomized controlled trials (RCTs) in younger populations with type 1 DM (T1DM).^1-3

One of the challenges in DM care has always been the wide variations in daily plasma glucose concentration that often cause major swings of hyperglycemia and hypoglycemia. Extreme variations in blood glucose have also been linked to adverse outcomes, including poor micro- and macrovascular outcomes.^4,5 AIP technology is a hybrid closed-loop system that attempts to solve this problem by adjusting insulin delivery in response to real-time glucose information from a continuous glucose monitor (CGM). Glucose measurements are sent to the insulin pump in real time, which uses a specialized algorithm to determine whether insulin delivery should be up-titrated, down-titrated, or suspended.⁶

Several studies have shown that AIP technology reduces glucose variability and increases the percentage of time within the optimal glucose range.^1-3,7 Its safety is especially indicated for patients with long-standing DM who often have hypoglycemia unawareness and recurrent episodes of hypoglycemia.⁷ Safety is the major advantage of the hybrid closed-loop system as long duration of DM makes patients particularly prone to emergency department (ED) visits and hospitalizations for severe hypoglycemia.⁸ Recurrent hypoglycemia also is associated with increased cardiovascular mortality in epidemiologic studies.⁹

Safety was the primary endpoint in the pivotal trial in a multicenter clinical study where 124 participants (mean age, 37.8 years; DM duration, 21.7 years; hemoglobin A_1c [HbA_1c], 7.4%) were monitored for 3 months while using a hybrid closed-loop pump, similar to the one used in our study.¹⁰ Remarkably, there were no device-related episodes of severe hypoglycemia or ketoacidosis. There was even a small but significant difference in HbA_1c (7.4% at baseline, 6.9% at 3 months) and of the time in target range measured by CGM from 66.7% at baseline to 72.2% at 3 months). However, the mean age of the population studied was young (mean age, 37.8 years). It is unclear how these results would translate for a population of older patients with T1DM. Moreover, use of AIP systems have not been systematically tested outside of carefully controlled studies, as it would be in middle-aged veterans followed in outpatient US Department of Veterans Affairs (VA) clinics. Such an approach in the context of optimal glucose monitoring combined with use of structured DM education can significantly reduce impaired awareness of hypoglycemia in patients with T1DM of long duration.¹¹

This is the first study to assess the feasibility of AIP technology in a real-world population of older veterans with T1DM in terms of safety and acceptability, because AIP has just recently become available for patient care in the Veterans Health Administration (VHA). This group of patients is of particular interest because they have been largely overlooked in earlier studies. They represent an older population with long-standing DM where hypoglycemia unawareness is often recurrent and incapacitating. In addition, long-standing DM makes optimal glycemic control mandatory to prevent microvascular complications.

Methods

In this retrospective review study,, we examined available data in patients with T1DM at the Malcom Randall VA Medical Center diabetes clinic in Gainesville, Florida, between March and December of 2018 who agreed to use AIP. In this clinic, the AIP system was offered to T1DM patients when the 4-year warranty of a previous insulin pump expired, they had frequent hypoglycemic events, or they were on multiple daily injections and were proficient with carbohydrate counting and adjusting insulin doses and willing to use an insulin pump. Veterans were trained on AIP use by a certified diabetes educator and pump trainer in sessions that lasted 2 to 4 hours depending on previous experience with AIP. Institutional review board approval was obtained at the University of Florida. 

Demographic and clinical data before and after the initiation of AIP were collected, including standard insulin pump/CGM information for the Medtronic 670G and Guardian 3 Sensor AIPs. Several variables were evaluated, including age, gender, year of DM diagnosis, time of initiation of AIP, HbA_1c, download data (percentage sensor wear, time in automated mode and manual mode, time in/above/below range, bolus information, insulin use, average sensor blood glucose, average meter blood glucose, pump settings), weight, body mass index (BMI), glucose meter information, history of hypoglycemia unawareness.

The primary outcome for this study was safety as assessed by percentage of time below target range on glucose sensor (time below target range is defined as < 70 mg/dL). We also addressed the secondary endpoint of efficacy as the percentage of time in-range defined as blood glucose per glucose sensor of 70 mg/dL to 180 mg/dL (efficacy), percentage of glucose sensor wear, and HbA_1c.

 

Statistics

Comparisons of changes in continuous variables between groups were performed by an analysis of covariance (ANCOVA), adjusting for baseline levels. Fisher exact test (χ²) and unpaired t test were used to compare group differences at baseline for categorical and continuous variables, respectively, while Wilcoxon rank sum test was used for nonnormally distributed values. Changes in continuous measures within the same group were tested by paired t test or Wilcoxon matched-pairs signed rank test when applicable. Analyses were performed using Stata 11.0.

Results

Thirty-seven veterans with T1DM using AIPs in 2018 were evaluated at baseline and at follow up visits (Tables 1 and 2). Time frame for follow-up was approximately 3 months, although there was some variation. Of note, the mean weight and BMI corresponded to mostly lean individuals, consistent with the diagnosis of T1DM.

Time below target range hypoglycemia (sensor glucose < 70 mg/dL) remained low at each follow-up visit (both 1.5%). Percentage of time in automated mode increased from first to second follow-up visit after initiation of AIP (41% vs 53%, P = .06). Percentage of sensor wear numerically increased from first to second follow-up visit (75% vs 85%, P = .39), same as time in range, defined as sensor glucose 70 to 180 mg/dL, from first to second follow-up visit (70% vs 73%, P = .09). Time above range, defined as sensor glucose > 180 mg/dL, demonstrated a strong trend toward decreasing between follow-up appointments (29% to 25%; P = .09). HbA_1c decreased from 7.6% to 7.3% (P = .005).

About half of the patients (18 of 37) reported hypoglycemia unawareness before the initiation of the 670G AIP. On follow-up visit 61% (11 of 18) reported significant improvement in awareness. Of the remaining 18 patients who reported normal awareness before automated mode, 17% (3 of 18) described a new onset unawareness.

Discussion

This study evaluated the safety of adopting a new DM technology in the real world of an outpatient VA clinic. To the best of our knowledge, this is the first study evaluating the use of AIP specifically in a population of middle-aged veterans with longstanding T1DM. After a mean 7 months of follow-up, participants accepted AIP use as evidenced by increased sensor wear over time and experienced improvements in DM measures that indicate successful use (ie, time in automated mode, which represents reduced glycemic variability). These results show success of an AIP approach in a demographically older group of patients.

AIP has been shown to have positive effects on glycemic control such as time in target glucose range (goal ≥ 70%). In our relatively small pilot study, there was trend for an improvement in the time in range from the first to second clinical follow-up visit, suggesting true patient involvement with the use of the device. Studies involving overall younger cohorts have proved that AIP technology is safe and efficacious for outpatient management of T1DM.^7,10,12,13 However, they were all conducted under the safety of a research setting, and trials enrolled a younger population believed to adapt with more ease to this new technology. Tauschmann and colleagues performed a multicenter, parallel randomized controlled trial that compared hybrid closed-loop AIP therapy with sensor-augmented pump therapy in patients with suboptimal T1DM control.¹² Results showed that the hybrid closed-loop system increased the time that the glucose concentration was within the target range (70-180 mg/dL) from 54% in the sensor-augmented pump group to 65% on the closed-loop system (P < .001). A small but significant improvement in HBA_1c (from 8.0 -7.4%) and low rates of hypoglycemia (2.6% of time below 70 mg/dL) were also noted.¹²

A similar benefit was observed in a 2019 landmark study by Brown and colleagues of 168 patients with T1DM at 7 university medical centers who were treated for 6 months with either a closed-loop system (closed-loop group) or a sensor-augmented pump (control group) in a parallel-group, unblinded, randomized trial study.¹³ Mean (SD) time in the target range increased in the closed-loop group from 61% (17) at baseline to 71% (12) during the 6 months. HbA_1c decreased from 7.4 to 7.1% and time ≤ 70 mg/dL was just 1.6%. However, only 13% of patients were aged ≥ 40 years in the study by Tauschmann and colleagues, and mean age was 33 years in the Brown and colleagues study.^12,13 In contrast, the mean (SD) age in our study was 59 (14) years. Our pilot study also showed comparable, or somewhat better results, as mean time in target range was 72%, HbA_1c was 7.3%, and time ≤ 70 mg/dL was just 1.5%.

 

In the only other single-center study in adults with T1DM (mean age 45 years), Faulds and colleagues evaluated changes in glycemic control and adherence in patient using the same hybrid closed-loop system.¹⁴ Treatment resulted in a decrease in HbA_1c compared with baseline similar to our study, most notably for patients who had higher baseline HbA_1c. However, over its short duration (6 to 12 weeks), there was decreased time in automated mode in study patients, likely due to treatment burden. Our study in older patients showed a similar reduction in HbA_1c from baseline up to the 7-month visit but with increased sensor wear and time in automated mode.

There are many possible reasons for improved time in target range in our older population. Contrary to common belief that older age may be a barrier to adopting complex technology, it is likely that older age and longer duration of DM motivates adherence to a therapy that reduces glucose swings, offers a greater sense of safety and control, and improves quality of life. This is underscored by improvements over time in sensor wear and time in automated mode, measures of adherence, and successful AIP management. In support of a motivation factor to adopt insulin pump therapy in patients with long-standing T1DM, Faulds and colleagues found that older age and higher baseline HbA_1c were associated with less time spent in hypoglycemia.¹⁴

The close supervision of patients by a certified diabetes educator and pump trainer may have helped improve glycemic control. Veterans received initial training, weekly follow-ups for 4 to 5 visits, and then bimonthly visits. There was also good access to the DM care team through a secure VA messaging system. This allowed for prompt troubleshooting and gave veterans the support they needed for the successful technology adoption.

The use of real-time CGM led to improvements in hypoglycemia unawareness. The nature of automated insulin delivery not only allows the patient to use a immediate CGM, but automatically lowers the delivery of insulin, further minimizing the risk of hypoglycemia.¹⁵ This combined approach explains the improvement in self-reported hypoglycemia unawareness in our cohort which decreased by 61%. As in our study, very recently Pratley and colleagues reported in a 6-month follow-up study that the greatest benefit of CGM was not the -0.3% improvement of glycemic control (similar in magnitude to our study) but the 47% decrease in the primary outcome of CGM-measured time in hypoglycemia.¹⁶

Hybrid closed-loop insulin delivery improves glucose control while reducing the risk of hypoglycemia. There is consensus that this approach is cost-effective and saves resources in the management of these complex patients, so prone to severe microvascular complications and hypoglycemia.^17,18 A recent analysis by Pease and colleagues concluded that the hybrid closed-loop system was safer and more cost-effective when compared with the current standard of care, comprising insulin injections and capillary glucose testing.¹⁹ This held true even after several sensitivity analyses were performed, including baseline glycemic control, treatment effects, technology costs, age, and time horizon. This is relevant to the VHA, which at all times must consider the most cost-effective approach. Therefore, while there is no such debate about the cost-effectiveness of AIP technology for younger adults with T1DM, this study closes the knowledge gap for middle-aged veterans.^7,10,12,13 The current study demonstrates that even for older patients with long-standing T1DM, when proper access to supplies and support services are made available, treatment is associated with considerable success.

Finally, AIP is well suited for telehealth applications. Data can be uploaded remotely and sent to VA health care providers, which can facilitate care without the need to travel. Distance is often a barrier for access and optimal care of veterans. The current COVID-19 pandemic is another barrier to access that may persist in the near future and adds value to AIP management.

There were a few challenges with use of AIP. Although transition to AIP was smooth for most patients already on insulin pump therapy, several noted requests for calibration in the middle of the night in automated mode, which affected sleep. Also, AIP technology requires some computer literacy to navigate the menu and address sensor calibrations, which can be a challenge for some. Based on our results, we would recommend AIP in veterans who are appropriately trained in carbohydrate counting, understand the principles of insulin therapy, and are able to navigate a computer screen menu. Most T1DM patients already using insulin pump meet those recommendations, thus, they are good candidates.

Limitations

There are some limitations to our study. The small sample size and single-center nature prevent generalization. Also, the veteran population cannot be extrapolated to other populations. For instance, the majority of the patients in this study were male.

Conclusions

We report that an AIP approach for patients with long-standing T1DM is well accepted and engages patients into monitoring their blood sugars and achieving better glycemic control. This was achieved with minimal hypoglycemia in a population where often hypoglycemia unawareness makes DM care a challenge. Future studies within the VHA are needed to fully assess the long-term benefits and cost-effectiveness of this technology in veterans.

Insulin pump technology has been available since the 1970s. Innovation in insulin pumps has had significant impact on the management of diabetes mellitus (DM). In recent years, automated insulin pump technology (AIP) has proven to be a safe and effective way to treat DM. It has been studied mostly in highly organized randomized controlled trials (RCTs) in younger populations with type 1 DM (T1DM).^1-3

One of the challenges in DM care has always been the wide variations in daily plasma glucose concentration that often cause major swings of hyperglycemia and hypoglycemia. Extreme variations in blood glucose have also been linked to adverse outcomes, including poor micro- and macrovascular outcomes.^4,5 AIP technology is a hybrid closed-loop system that attempts to solve this problem by adjusting insulin delivery in response to real-time glucose information from a continuous glucose monitor (CGM). Glucose measurements are sent to the insulin pump in real time, which uses a specialized algorithm to determine whether insulin delivery should be up-titrated, down-titrated, or suspended.⁶

Several studies have shown that AIP technology reduces glucose variability and increases the percentage of time within the optimal glucose range.^1-3,7 Its safety is especially indicated for patients with long-standing DM who often have hypoglycemia unawareness and recurrent episodes of hypoglycemia.⁷ Safety is the major advantage of the hybrid closed-loop system as long duration of DM makes patients particularly prone to emergency department (ED) visits and hospitalizations for severe hypoglycemia.⁸ Recurrent hypoglycemia also is associated with increased cardiovascular mortality in epidemiologic studies.⁹

Safety was the primary endpoint in the pivotal trial in a multicenter clinical study where 124 participants (mean age, 37.8 years; DM duration, 21.7 years; hemoglobin A_1c [HbA_1c], 7.4%) were monitored for 3 months while using a hybrid closed-loop pump, similar to the one used in our study.¹⁰ Remarkably, there were no device-related episodes of severe hypoglycemia or ketoacidosis. There was even a small but significant difference in HbA_1c (7.4% at baseline, 6.9% at 3 months) and of the time in target range measured by CGM from 66.7% at baseline to 72.2% at 3 months). However, the mean age of the population studied was young (mean age, 37.8 years). It is unclear how these results would translate for a population of older patients with T1DM. Moreover, use of AIP systems have not been systematically tested outside of carefully controlled studies, as it would be in middle-aged veterans followed in outpatient US Department of Veterans Affairs (VA) clinics. Such an approach in the context of optimal glucose monitoring combined with use of structured DM education can significantly reduce impaired awareness of hypoglycemia in patients with T1DM of long duration.¹¹

This is the first study to assess the feasibility of AIP technology in a real-world population of older veterans with T1DM in terms of safety and acceptability, because AIP has just recently become available for patient care in the Veterans Health Administration (VHA). This group of patients is of particular interest because they have been largely overlooked in earlier studies. They represent an older population with long-standing DM where hypoglycemia unawareness is often recurrent and incapacitating. In addition, long-standing DM makes optimal glycemic control mandatory to prevent microvascular complications.

Methods

In this retrospective review study,, we examined available data in patients with T1DM at the Malcom Randall VA Medical Center diabetes clinic in Gainesville, Florida, between March and December of 2018 who agreed to use AIP. In this clinic, the AIP system was offered to T1DM patients when the 4-year warranty of a previous insulin pump expired, they had frequent hypoglycemic events, or they were on multiple daily injections and were proficient with carbohydrate counting and adjusting insulin doses and willing to use an insulin pump. Veterans were trained on AIP use by a certified diabetes educator and pump trainer in sessions that lasted 2 to 4 hours depending on previous experience with AIP. Institutional review board approval was obtained at the University of Florida. 

Demographic and clinical data before and after the initiation of AIP were collected, including standard insulin pump/CGM information for the Medtronic 670G and Guardian 3 Sensor AIPs. Several variables were evaluated, including age, gender, year of DM diagnosis, time of initiation of AIP, HbA_1c, download data (percentage sensor wear, time in automated mode and manual mode, time in/above/below range, bolus information, insulin use, average sensor blood glucose, average meter blood glucose, pump settings), weight, body mass index (BMI), glucose meter information, history of hypoglycemia unawareness.

The primary outcome for this study was safety as assessed by percentage of time below target range on glucose sensor (time below target range is defined as < 70 mg/dL). We also addressed the secondary endpoint of efficacy as the percentage of time in-range defined as blood glucose per glucose sensor of 70 mg/dL to 180 mg/dL (efficacy), percentage of glucose sensor wear, and HbA_1c.

 

Statistics

Comparisons of changes in continuous variables between groups were performed by an analysis of covariance (ANCOVA), adjusting for baseline levels. Fisher exact test (χ²) and unpaired t test were used to compare group differences at baseline for categorical and continuous variables, respectively, while Wilcoxon rank sum test was used for nonnormally distributed values. Changes in continuous measures within the same group were tested by paired t test or Wilcoxon matched-pairs signed rank test when applicable. Analyses were performed using Stata 11.0.

Results

Thirty-seven veterans with T1DM using AIPs in 2018 were evaluated at baseline and at follow up visits (Tables 1 and 2). Time frame for follow-up was approximately 3 months, although there was some variation. Of note, the mean weight and BMI corresponded to mostly lean individuals, consistent with the diagnosis of T1DM.

Time below target range hypoglycemia (sensor glucose < 70 mg/dL) remained low at each follow-up visit (both 1.5%). Percentage of time in automated mode increased from first to second follow-up visit after initiation of AIP (41% vs 53%, P = .06). Percentage of sensor wear numerically increased from first to second follow-up visit (75% vs 85%, P = .39), same as time in range, defined as sensor glucose 70 to 180 mg/dL, from first to second follow-up visit (70% vs 73%, P = .09). Time above range, defined as sensor glucose > 180 mg/dL, demonstrated a strong trend toward decreasing between follow-up appointments (29% to 25%; P = .09). HbA_1c decreased from 7.6% to 7.3% (P = .005).

About half of the patients (18 of 37) reported hypoglycemia unawareness before the initiation of the 670G AIP. On follow-up visit 61% (11 of 18) reported significant improvement in awareness. Of the remaining 18 patients who reported normal awareness before automated mode, 17% (3 of 18) described a new onset unawareness.

Discussion

This study evaluated the safety of adopting a new DM technology in the real world of an outpatient VA clinic. To the best of our knowledge, this is the first study evaluating the use of AIP specifically in a population of middle-aged veterans with longstanding T1DM. After a mean 7 months of follow-up, participants accepted AIP use as evidenced by increased sensor wear over time and experienced improvements in DM measures that indicate successful use (ie, time in automated mode, which represents reduced glycemic variability). These results show success of an AIP approach in a demographically older group of patients.

AIP has been shown to have positive effects on glycemic control such as time in target glucose range (goal ≥ 70%). In our relatively small pilot study, there was trend for an improvement in the time in range from the first to second clinical follow-up visit, suggesting true patient involvement with the use of the device. Studies involving overall younger cohorts have proved that AIP technology is safe and efficacious for outpatient management of T1DM.^7,10,12,13 However, they were all conducted under the safety of a research setting, and trials enrolled a younger population believed to adapt with more ease to this new technology. Tauschmann and colleagues performed a multicenter, parallel randomized controlled trial that compared hybrid closed-loop AIP therapy with sensor-augmented pump therapy in patients with suboptimal T1DM control.¹² Results showed that the hybrid closed-loop system increased the time that the glucose concentration was within the target range (70-180 mg/dL) from 54% in the sensor-augmented pump group to 65% on the closed-loop system (P < .001). A small but significant improvement in HBA_1c (from 8.0 -7.4%) and low rates of hypoglycemia (2.6% of time below 70 mg/dL) were also noted.¹²

A similar benefit was observed in a 2019 landmark study by Brown and colleagues of 168 patients with T1DM at 7 university medical centers who were treated for 6 months with either a closed-loop system (closed-loop group) or a sensor-augmented pump (control group) in a parallel-group, unblinded, randomized trial study.¹³ Mean (SD) time in the target range increased in the closed-loop group from 61% (17) at baseline to 71% (12) during the 6 months. HbA_1c decreased from 7.4 to 7.1% and time ≤ 70 mg/dL was just 1.6%. However, only 13% of patients were aged ≥ 40 years in the study by Tauschmann and colleagues, and mean age was 33 years in the Brown and colleagues study.^12,13 In contrast, the mean (SD) age in our study was 59 (14) years. Our pilot study also showed comparable, or somewhat better results, as mean time in target range was 72%, HbA_1c was 7.3%, and time ≤ 70 mg/dL was just 1.5%.

 

In the only other single-center study in adults with T1DM (mean age 45 years), Faulds and colleagues evaluated changes in glycemic control and adherence in patient using the same hybrid closed-loop system.¹⁴ Treatment resulted in a decrease in HbA_1c compared with baseline similar to our study, most notably for patients who had higher baseline HbA_1c. However, over its short duration (6 to 12 weeks), there was decreased time in automated mode in study patients, likely due to treatment burden. Our study in older patients showed a similar reduction in HbA_1c from baseline up to the 7-month visit but with increased sensor wear and time in automated mode.

There are many possible reasons for improved time in target range in our older population. Contrary to common belief that older age may be a barrier to adopting complex technology, it is likely that older age and longer duration of DM motivates adherence to a therapy that reduces glucose swings, offers a greater sense of safety and control, and improves quality of life. This is underscored by improvements over time in sensor wear and time in automated mode, measures of adherence, and successful AIP management. In support of a motivation factor to adopt insulin pump therapy in patients with long-standing T1DM, Faulds and colleagues found that older age and higher baseline HbA_1c were associated with less time spent in hypoglycemia.¹⁴

The close supervision of patients by a certified diabetes educator and pump trainer may have helped improve glycemic control. Veterans received initial training, weekly follow-ups for 4 to 5 visits, and then bimonthly visits. There was also good access to the DM care team through a secure VA messaging system. This allowed for prompt troubleshooting and gave veterans the support they needed for the successful technology adoption.

The use of real-time CGM led to improvements in hypoglycemia unawareness. The nature of automated insulin delivery not only allows the patient to use a immediate CGM, but automatically lowers the delivery of insulin, further minimizing the risk of hypoglycemia.¹⁵ This combined approach explains the improvement in self-reported hypoglycemia unawareness in our cohort which decreased by 61%. As in our study, very recently Pratley and colleagues reported in a 6-month follow-up study that the greatest benefit of CGM was not the -0.3% improvement of glycemic control (similar in magnitude to our study) but the 47% decrease in the primary outcome of CGM-measured time in hypoglycemia.¹⁶

Hybrid closed-loop insulin delivery improves glucose control while reducing the risk of hypoglycemia. There is consensus that this approach is cost-effective and saves resources in the management of these complex patients, so prone to severe microvascular complications and hypoglycemia.^17,18 A recent analysis by Pease and colleagues concluded that the hybrid closed-loop system was safer and more cost-effective when compared with the current standard of care, comprising insulin injections and capillary glucose testing.¹⁹ This held true even after several sensitivity analyses were performed, including baseline glycemic control, treatment effects, technology costs, age, and time horizon. This is relevant to the VHA, which at all times must consider the most cost-effective approach. Therefore, while there is no such debate about the cost-effectiveness of AIP technology for younger adults with T1DM, this study closes the knowledge gap for middle-aged veterans.^7,10,12,13 The current study demonstrates that even for older patients with long-standing T1DM, when proper access to supplies and support services are made available, treatment is associated with considerable success.

Finally, AIP is well suited for telehealth applications. Data can be uploaded remotely and sent to VA health care providers, which can facilitate care without the need to travel. Distance is often a barrier for access and optimal care of veterans. The current COVID-19 pandemic is another barrier to access that may persist in the near future and adds value to AIP management.

There were a few challenges with use of AIP. Although transition to AIP was smooth for most patients already on insulin pump therapy, several noted requests for calibration in the middle of the night in automated mode, which affected sleep. Also, AIP technology requires some computer literacy to navigate the menu and address sensor calibrations, which can be a challenge for some. Based on our results, we would recommend AIP in veterans who are appropriately trained in carbohydrate counting, understand the principles of insulin therapy, and are able to navigate a computer screen menu. Most T1DM patients already using insulin pump meet those recommendations, thus, they are good candidates.

Limitations

There are some limitations to our study. The small sample size and single-center nature prevent generalization. Also, the veteran population cannot be extrapolated to other populations. For instance, the majority of the patients in this study were male.

Conclusions

We report that an AIP approach for patients with long-standing T1DM is well accepted and engages patients into monitoring their blood sugars and achieving better glycemic control. This was achieved with minimal hypoglycemia in a population where often hypoglycemia unawareness makes DM care a challenge. Future studies within the VHA are needed to fully assess the long-term benefits and cost-effectiveness of this technology in veterans.

Insulin pump technology has been available since the 1970s. Innovation in insulin pumps has had significant impact on the management of diabetes mellitus (DM). In recent years, automated insulin pump technology (AIP) has proven to be a safe and effective way to treat DM. It has been studied mostly in highly organized randomized controlled trials (RCTs) in younger populations with type 1 DM (T1DM).^1-3

One of the challenges in DM care has always been the wide variations in daily plasma glucose concentration that often cause major swings of hyperglycemia and hypoglycemia. Extreme variations in blood glucose have also been linked to adverse outcomes, including poor micro- and macrovascular outcomes.^4,5 AIP technology is a hybrid closed-loop system that attempts to solve this problem by adjusting insulin delivery in response to real-time glucose information from a continuous glucose monitor (CGM). Glucose measurements are sent to the insulin pump in real time, which uses a specialized algorithm to determine whether insulin delivery should be up-titrated, down-titrated, or suspended.⁶

Several studies have shown that AIP technology reduces glucose variability and increases the percentage of time within the optimal glucose range.^1-3,7 Its safety is especially indicated for patients with long-standing DM who often have hypoglycemia unawareness and recurrent episodes of hypoglycemia.⁷ Safety is the major advantage of the hybrid closed-loop system as long duration of DM makes patients particularly prone to emergency department (ED) visits and hospitalizations for severe hypoglycemia.⁸ Recurrent hypoglycemia also is associated with increased cardiovascular mortality in epidemiologic studies.⁹

Safety was the primary endpoint in the pivotal trial in a multicenter clinical study where 124 participants (mean age, 37.8 years; DM duration, 21.7 years; hemoglobin A_1c [HbA_1c], 7.4%) were monitored for 3 months while using a hybrid closed-loop pump, similar to the one used in our study.¹⁰ Remarkably, there were no device-related episodes of severe hypoglycemia or ketoacidosis. There was even a small but significant difference in HbA_1c (7.4% at baseline, 6.9% at 3 months) and of the time in target range measured by CGM from 66.7% at baseline to 72.2% at 3 months). However, the mean age of the population studied was young (mean age, 37.8 years). It is unclear how these results would translate for a population of older patients with T1DM. Moreover, use of AIP systems have not been systematically tested outside of carefully controlled studies, as it would be in middle-aged veterans followed in outpatient US Department of Veterans Affairs (VA) clinics. Such an approach in the context of optimal glucose monitoring combined with use of structured DM education can significantly reduce impaired awareness of hypoglycemia in patients with T1DM of long duration.¹¹

This is the first study to assess the feasibility of AIP technology in a real-world population of older veterans with T1DM in terms of safety and acceptability, because AIP has just recently become available for patient care in the Veterans Health Administration (VHA). This group of patients is of particular interest because they have been largely overlooked in earlier studies. They represent an older population with long-standing DM where hypoglycemia unawareness is often recurrent and incapacitating. In addition, long-standing DM makes optimal glycemic control mandatory to prevent microvascular complications.

Methods

In this retrospective review study,, we examined available data in patients with T1DM at the Malcom Randall VA Medical Center diabetes clinic in Gainesville, Florida, between March and December of 2018 who agreed to use AIP. In this clinic, the AIP system was offered to T1DM patients when the 4-year warranty of a previous insulin pump expired, they had frequent hypoglycemic events, or they were on multiple daily injections and were proficient with carbohydrate counting and adjusting insulin doses and willing to use an insulin pump. Veterans were trained on AIP use by a certified diabetes educator and pump trainer in sessions that lasted 2 to 4 hours depending on previous experience with AIP. Institutional review board approval was obtained at the University of Florida. 

Demographic and clinical data before and after the initiation of AIP were collected, including standard insulin pump/CGM information for the Medtronic 670G and Guardian 3 Sensor AIPs. Several variables were evaluated, including age, gender, year of DM diagnosis, time of initiation of AIP, HbA_1c, download data (percentage sensor wear, time in automated mode and manual mode, time in/above/below range, bolus information, insulin use, average sensor blood glucose, average meter blood glucose, pump settings), weight, body mass index (BMI), glucose meter information, history of hypoglycemia unawareness.

The primary outcome for this study was safety as assessed by percentage of time below target range on glucose sensor (time below target range is defined as < 70 mg/dL). We also addressed the secondary endpoint of efficacy as the percentage of time in-range defined as blood glucose per glucose sensor of 70 mg/dL to 180 mg/dL (efficacy), percentage of glucose sensor wear, and HbA_1c.

 

Statistics

Comparisons of changes in continuous variables between groups were performed by an analysis of covariance (ANCOVA), adjusting for baseline levels. Fisher exact test (χ²) and unpaired t test were used to compare group differences at baseline for categorical and continuous variables, respectively, while Wilcoxon rank sum test was used for nonnormally distributed values. Changes in continuous measures within the same group were tested by paired t test or Wilcoxon matched-pairs signed rank test when applicable. Analyses were performed using Stata 11.0.

Results

Thirty-seven veterans with T1DM using AIPs in 2018 were evaluated at baseline and at follow up visits (Tables 1 and 2). Time frame for follow-up was approximately 3 months, although there was some variation. Of note, the mean weight and BMI corresponded to mostly lean individuals, consistent with the diagnosis of T1DM.

Time below target range hypoglycemia (sensor glucose < 70 mg/dL) remained low at each follow-up visit (both 1.5%). Percentage of time in automated mode increased from first to second follow-up visit after initiation of AIP (41% vs 53%, P = .06). Percentage of sensor wear numerically increased from first to second follow-up visit (75% vs 85%, P = .39), same as time in range, defined as sensor glucose 70 to 180 mg/dL, from first to second follow-up visit (70% vs 73%, P = .09). Time above range, defined as sensor glucose > 180 mg/dL, demonstrated a strong trend toward decreasing between follow-up appointments (29% to 25%; P = .09). HbA_1c decreased from 7.6% to 7.3% (P = .005).

About half of the patients (18 of 37) reported hypoglycemia unawareness before the initiation of the 670G AIP. On follow-up visit 61% (11 of 18) reported significant improvement in awareness. Of the remaining 18 patients who reported normal awareness before automated mode, 17% (3 of 18) described a new onset unawareness.

Discussion

This study evaluated the safety of adopting a new DM technology in the real world of an outpatient VA clinic. To the best of our knowledge, this is the first study evaluating the use of AIP specifically in a population of middle-aged veterans with longstanding T1DM. After a mean 7 months of follow-up, participants accepted AIP use as evidenced by increased sensor wear over time and experienced improvements in DM measures that indicate successful use (ie, time in automated mode, which represents reduced glycemic variability). These results show success of an AIP approach in a demographically older group of patients.

AIP has been shown to have positive effects on glycemic control such as time in target glucose range (goal ≥ 70%). In our relatively small pilot study, there was trend for an improvement in the time in range from the first to second clinical follow-up visit, suggesting true patient involvement with the use of the device. Studies involving overall younger cohorts have proved that AIP technology is safe and efficacious for outpatient management of T1DM.^7,10,12,13 However, they were all conducted under the safety of a research setting, and trials enrolled a younger population believed to adapt with more ease to this new technology. Tauschmann and colleagues performed a multicenter, parallel randomized controlled trial that compared hybrid closed-loop AIP therapy with sensor-augmented pump therapy in patients with suboptimal T1DM control.¹² Results showed that the hybrid closed-loop system increased the time that the glucose concentration was within the target range (70-180 mg/dL) from 54% in the sensor-augmented pump group to 65% on the closed-loop system (P < .001). A small but significant improvement in HBA_1c (from 8.0 -7.4%) and low rates of hypoglycemia (2.6% of time below 70 mg/dL) were also noted.¹²

A similar benefit was observed in a 2019 landmark study by Brown and colleagues of 168 patients with T1DM at 7 university medical centers who were treated for 6 months with either a closed-loop system (closed-loop group) or a sensor-augmented pump (control group) in a parallel-group, unblinded, randomized trial study.¹³ Mean (SD) time in the target range increased in the closed-loop group from 61% (17) at baseline to 71% (12) during the 6 months. HbA_1c decreased from 7.4 to 7.1% and time ≤ 70 mg/dL was just 1.6%. However, only 13% of patients were aged ≥ 40 years in the study by Tauschmann and colleagues, and mean age was 33 years in the Brown and colleagues study.^12,13 In contrast, the mean (SD) age in our study was 59 (14) years. Our pilot study also showed comparable, or somewhat better results, as mean time in target range was 72%, HbA_1c was 7.3%, and time ≤ 70 mg/dL was just 1.5%.

 

In the only other single-center study in adults with T1DM (mean age 45 years), Faulds and colleagues evaluated changes in glycemic control and adherence in patient using the same hybrid closed-loop system.¹⁴ Treatment resulted in a decrease in HbA_1c compared with baseline similar to our study, most notably for patients who had higher baseline HbA_1c. However, over its short duration (6 to 12 weeks), there was decreased time in automated mode in study patients, likely due to treatment burden. Our study in older patients showed a similar reduction in HbA_1c from baseline up to the 7-month visit but with increased sensor wear and time in automated mode.

There are many possible reasons for improved time in target range in our older population. Contrary to common belief that older age may be a barrier to adopting complex technology, it is likely that older age and longer duration of DM motivates adherence to a therapy that reduces glucose swings, offers a greater sense of safety and control, and improves quality of life. This is underscored by improvements over time in sensor wear and time in automated mode, measures of adherence, and successful AIP management. In support of a motivation factor to adopt insulin pump therapy in patients with long-standing T1DM, Faulds and colleagues found that older age and higher baseline HbA_1c were associated with less time spent in hypoglycemia.¹⁴

The close supervision of patients by a certified diabetes educator and pump trainer may have helped improve glycemic control. Veterans received initial training, weekly follow-ups for 4 to 5 visits, and then bimonthly visits. There was also good access to the DM care team through a secure VA messaging system. This allowed for prompt troubleshooting and gave veterans the support they needed for the successful technology adoption.

The use of real-time CGM led to improvements in hypoglycemia unawareness. The nature of automated insulin delivery not only allows the patient to use a immediate CGM, but automatically lowers the delivery of insulin, further minimizing the risk of hypoglycemia.¹⁵ This combined approach explains the improvement in self-reported hypoglycemia unawareness in our cohort which decreased by 61%. As in our study, very recently Pratley and colleagues reported in a 6-month follow-up study that the greatest benefit of CGM was not the -0.3% improvement of glycemic control (similar in magnitude to our study) but the 47% decrease in the primary outcome of CGM-measured time in hypoglycemia.¹⁶

Hybrid closed-loop insulin delivery improves glucose control while reducing the risk of hypoglycemia. There is consensus that this approach is cost-effective and saves resources in the management of these complex patients, so prone to severe microvascular complications and hypoglycemia.^17,18 A recent analysis by Pease and colleagues concluded that the hybrid closed-loop system was safer and more cost-effective when compared with the current standard of care, comprising insulin injections and capillary glucose testing.¹⁹ This held true even after several sensitivity analyses were performed, including baseline glycemic control, treatment effects, technology costs, age, and time horizon. This is relevant to the VHA, which at all times must consider the most cost-effective approach. Therefore, while there is no such debate about the cost-effectiveness of AIP technology for younger adults with T1DM, this study closes the knowledge gap for middle-aged veterans.^7,10,12,13 The current study demonstrates that even for older patients with long-standing T1DM, when proper access to supplies and support services are made available, treatment is associated with considerable success.

Finally, AIP is well suited for telehealth applications. Data can be uploaded remotely and sent to VA health care providers, which can facilitate care without the need to travel. Distance is often a barrier for access and optimal care of veterans. The current COVID-19 pandemic is another barrier to access that may persist in the near future and adds value to AIP management.

There were a few challenges with use of AIP. Although transition to AIP was smooth for most patients already on insulin pump therapy, several noted requests for calibration in the middle of the night in automated mode, which affected sleep. Also, AIP technology requires some computer literacy to navigate the menu and address sensor calibrations, which can be a challenge for some. Based on our results, we would recommend AIP in veterans who are appropriately trained in carbohydrate counting, understand the principles of insulin therapy, and are able to navigate a computer screen menu. Most T1DM patients already using insulin pump meet those recommendations, thus, they are good candidates.

Limitations

There are some limitations to our study. The small sample size and single-center nature prevent generalization. Also, the veteran population cannot be extrapolated to other populations. For instance, the majority of the patients in this study were male.

Conclusions

We report that an AIP approach for patients with long-standing T1DM is well accepted and engages patients into monitoring their blood sugars and achieving better glycemic control. This was achieved with minimal hypoglycemia in a population where often hypoglycemia unawareness makes DM care a challenge. Future studies within the VHA are needed to fully assess the long-term benefits and cost-effectiveness of this technology in veterans.

About 40% of patients with heart failure (HF) also have type 2 diabetes mellitus (T2DM).¹ Certain sodium-glucose cotransporter-2 (SGLT2) inhibitors have benefited patients with HF.² We report a case of a patient with T2DM who had signs and symptoms of hypervolemia after discontinuing the SGLT2 inhibitor empagliflozin. The patient was found to have previously undiagnosed HF. This case highlights the relationship between T2DM and HF and the benefits of treatment with SGLT2 inhibitors.

Case Presentation

A 58-year-old male presented for care at Malcolm Randall Veterans Affairs Medical Center in Gainseville, Florida, diabetes clinic. The patient was diagnosed with T2DM at age 32 years. At 36 years, he was started on subcutaneous insulin injections, and was switched to insulin pump therapy in his early 40s. At the time of evaluation, the T2DM was managed using an insulin pump, metformin, and acarbose. He had been prescribed empagliflozin 10 mg several months before presentation, but the medication ran out about 1 month prior to evaluation, and additional refills were unavailable.

The patient reported a 1-month history of worsening exertional shortness of breath, decreased exercise tolerance, and lower extremity swelling. Vitals signs, including respiratory rate and oxygen saturation were within normal limits. Bibasilar crackles and bilateral 2+ pitting pedal edema were noted. The remaining examination was unrevealing. His most recent glycated hemoglobin A_1c level from 1 month prior to the presentation was 6.4%.

Given the patient’s shortness of breath and evidence of fluid overload on examination, brain natriuretic peptide was obtained and was significantly elevated at 5,895 pg/mL. A transthoracic echocardiogram revealed left ventricular ejection fraction < 20%. The patient was started on furosemide 40 mg, pending receipt of empagliflozin. A cardiology evaluation also was recommended.

Cardiac catheterization identified significant obstructions to the left anterior descending and left circumflex arteries. The patient underwent successful percutaneous coronary intervention to these areas. Following initiation of medications and coronary revascularization, the patient reported significant symptom improvement. At the follow-up evaluation 8 weeks later, he was symptom free, and his physical examination was consistent with euvolemia.

Discussion

T2DM has been associated with adverse cardiovascular outcomes, including atherosclerotic heart disease and HF. There are several theories about the relationship between T2DM and HF, though the exact pathophysiology of this relationship is unknown.^3,4 One theory suggests diabetic cardiomyopathy as the cause. In patients with diabetic cardiomyopathy, there is early development of diastolic dysfunction, which eventually progresses to ventricular dysfunction. There is continued stimulation of the renin-angiotensin-aldosterone system that leads to death of cardiomyocytes, fibrosis, and remodeling, which worsens pump failure.⁵

SGLT2 inhibitors decrease hyperglycemia and hyperinsulinemia, potentially reducing HF risk. SGLT2 inhibitors decrease blood glucose levels by inhibiting SGLT2 in the proximal tubule, leading to a decrease of glucose reabsorption and an increase in excretion.^6,7 The EMPA-REG OUTCOME trial looked at cardiovascular outcomes in patients with T2DM at high risk for adverse cardiac events. There was a significant risk reduction in deaths and hospitalizations for HF in patients treated with empagliflozin.⁸

 

The EMPRISE study specifically examined empagliflozin and its effects on hospitalization for HF.² When compared with patients treated with sitagliptin, there was a statistically significant decrease in hospitalization for HF in patients with T2DM, both with and without preexisting cardiovascular disease.

This case highlights the relationship between T2DM and HF. We also show how the use of empagliflozin may have helped manage the patient’s undiagnosed HF and how its discontinuation luckily unmasked it. Routine evaluation for HF in patients with T2DM is not done, but likely there are patients who would benefit, especially given the strong, albeit less known, association between these 2 conditions.

Further studies are needed to determine the type of patients who would benefit most from HF screening. For now, the best practice is to obtain a complete medical history that includes current and recently discontinued medications as well a thorough physical examination for signs of fluid overload and cardiovascular compromise. Patients who may have signs concerning for HF can have appropriate testing and intervention.

Conclusions

SGLT2 inhibitors have been shown to have a role in the management of HF in patients with T2DM. There is a risk of exacerbation or unmasking of HF when discontinuing SGLT2 inhibitors. To our knowledge, this is the first paper describing the discovery of HF following interruption of SGLT2 inhibitor treatment. The clinician and patient should monitor for signs and symptoms of fluid overload when stopping therapy. Further research into the benefits of a more comprehensive evaluation is needed.

About 40% of patients with heart failure (HF) also have type 2 diabetes mellitus (T2DM).¹ Certain sodium-glucose cotransporter-2 (SGLT2) inhibitors have benefited patients with HF.² We report a case of a patient with T2DM who had signs and symptoms of hypervolemia after discontinuing the SGLT2 inhibitor empagliflozin. The patient was found to have previously undiagnosed HF. This case highlights the relationship between T2DM and HF and the benefits of treatment with SGLT2 inhibitors.

Case Presentation

A 58-year-old male presented for care at Malcolm Randall Veterans Affairs Medical Center in Gainseville, Florida, diabetes clinic. The patient was diagnosed with T2DM at age 32 years. At 36 years, he was started on subcutaneous insulin injections, and was switched to insulin pump therapy in his early 40s. At the time of evaluation, the T2DM was managed using an insulin pump, metformin, and acarbose. He had been prescribed empagliflozin 10 mg several months before presentation, but the medication ran out about 1 month prior to evaluation, and additional refills were unavailable.

The patient reported a 1-month history of worsening exertional shortness of breath, decreased exercise tolerance, and lower extremity swelling. Vitals signs, including respiratory rate and oxygen saturation were within normal limits. Bibasilar crackles and bilateral 2+ pitting pedal edema were noted. The remaining examination was unrevealing. His most recent glycated hemoglobin A_1c level from 1 month prior to the presentation was 6.4%.

Given the patient’s shortness of breath and evidence of fluid overload on examination, brain natriuretic peptide was obtained and was significantly elevated at 5,895 pg/mL. A transthoracic echocardiogram revealed left ventricular ejection fraction < 20%. The patient was started on furosemide 40 mg, pending receipt of empagliflozin. A cardiology evaluation also was recommended.

Cardiac catheterization identified significant obstructions to the left anterior descending and left circumflex arteries. The patient underwent successful percutaneous coronary intervention to these areas. Following initiation of medications and coronary revascularization, the patient reported significant symptom improvement. At the follow-up evaluation 8 weeks later, he was symptom free, and his physical examination was consistent with euvolemia.

Discussion

T2DM has been associated with adverse cardiovascular outcomes, including atherosclerotic heart disease and HF. There are several theories about the relationship between T2DM and HF, though the exact pathophysiology of this relationship is unknown.^3,4 One theory suggests diabetic cardiomyopathy as the cause. In patients with diabetic cardiomyopathy, there is early development of diastolic dysfunction, which eventually progresses to ventricular dysfunction. There is continued stimulation of the renin-angiotensin-aldosterone system that leads to death of cardiomyocytes, fibrosis, and remodeling, which worsens pump failure.⁵

SGLT2 inhibitors decrease hyperglycemia and hyperinsulinemia, potentially reducing HF risk. SGLT2 inhibitors decrease blood glucose levels by inhibiting SGLT2 in the proximal tubule, leading to a decrease of glucose reabsorption and an increase in excretion.^6,7 The EMPA-REG OUTCOME trial looked at cardiovascular outcomes in patients with T2DM at high risk for adverse cardiac events. There was a significant risk reduction in deaths and hospitalizations for HF in patients treated with empagliflozin.⁸

 

The EMPRISE study specifically examined empagliflozin and its effects on hospitalization for HF.² When compared with patients treated with sitagliptin, there was a statistically significant decrease in hospitalization for HF in patients with T2DM, both with and without preexisting cardiovascular disease.

This case highlights the relationship between T2DM and HF. We also show how the use of empagliflozin may have helped manage the patient’s undiagnosed HF and how its discontinuation luckily unmasked it. Routine evaluation for HF in patients with T2DM is not done, but likely there are patients who would benefit, especially given the strong, albeit less known, association between these 2 conditions.

Further studies are needed to determine the type of patients who would benefit most from HF screening. For now, the best practice is to obtain a complete medical history that includes current and recently discontinued medications as well a thorough physical examination for signs of fluid overload and cardiovascular compromise. Patients who may have signs concerning for HF can have appropriate testing and intervention.

Conclusions

SGLT2 inhibitors have been shown to have a role in the management of HF in patients with T2DM. There is a risk of exacerbation or unmasking of HF when discontinuing SGLT2 inhibitors. To our knowledge, this is the first paper describing the discovery of HF following interruption of SGLT2 inhibitor treatment. The clinician and patient should monitor for signs and symptoms of fluid overload when stopping therapy. Further research into the benefits of a more comprehensive evaluation is needed.

About 40% of patients with heart failure (HF) also have type 2 diabetes mellitus (T2DM).¹ Certain sodium-glucose cotransporter-2 (SGLT2) inhibitors have benefited patients with HF.² We report a case of a patient with T2DM who had signs and symptoms of hypervolemia after discontinuing the SGLT2 inhibitor empagliflozin. The patient was found to have previously undiagnosed HF. This case highlights the relationship between T2DM and HF and the benefits of treatment with SGLT2 inhibitors.

Case Presentation

A 58-year-old male presented for care at Malcolm Randall Veterans Affairs Medical Center in Gainseville, Florida, diabetes clinic. The patient was diagnosed with T2DM at age 32 years. At 36 years, he was started on subcutaneous insulin injections, and was switched to insulin pump therapy in his early 40s. At the time of evaluation, the T2DM was managed using an insulin pump, metformin, and acarbose. He had been prescribed empagliflozin 10 mg several months before presentation, but the medication ran out about 1 month prior to evaluation, and additional refills were unavailable.

The patient reported a 1-month history of worsening exertional shortness of breath, decreased exercise tolerance, and lower extremity swelling. Vitals signs, including respiratory rate and oxygen saturation were within normal limits. Bibasilar crackles and bilateral 2+ pitting pedal edema were noted. The remaining examination was unrevealing. His most recent glycated hemoglobin A_1c level from 1 month prior to the presentation was 6.4%.

Given the patient’s shortness of breath and evidence of fluid overload on examination, brain natriuretic peptide was obtained and was significantly elevated at 5,895 pg/mL. A transthoracic echocardiogram revealed left ventricular ejection fraction < 20%. The patient was started on furosemide 40 mg, pending receipt of empagliflozin. A cardiology evaluation also was recommended.

Cardiac catheterization identified significant obstructions to the left anterior descending and left circumflex arteries. The patient underwent successful percutaneous coronary intervention to these areas. Following initiation of medications and coronary revascularization, the patient reported significant symptom improvement. At the follow-up evaluation 8 weeks later, he was symptom free, and his physical examination was consistent with euvolemia.

Discussion

T2DM has been associated with adverse cardiovascular outcomes, including atherosclerotic heart disease and HF. There are several theories about the relationship between T2DM and HF, though the exact pathophysiology of this relationship is unknown.^3,4 One theory suggests diabetic cardiomyopathy as the cause. In patients with diabetic cardiomyopathy, there is early development of diastolic dysfunction, which eventually progresses to ventricular dysfunction. There is continued stimulation of the renin-angiotensin-aldosterone system that leads to death of cardiomyocytes, fibrosis, and remodeling, which worsens pump failure.⁵

SGLT2 inhibitors decrease hyperglycemia and hyperinsulinemia, potentially reducing HF risk. SGLT2 inhibitors decrease blood glucose levels by inhibiting SGLT2 in the proximal tubule, leading to a decrease of glucose reabsorption and an increase in excretion.^6,7 The EMPA-REG OUTCOME trial looked at cardiovascular outcomes in patients with T2DM at high risk for adverse cardiac events. There was a significant risk reduction in deaths and hospitalizations for HF in patients treated with empagliflozin.⁸

 

The EMPRISE study specifically examined empagliflozin and its effects on hospitalization for HF.² When compared with patients treated with sitagliptin, there was a statistically significant decrease in hospitalization for HF in patients with T2DM, both with and without preexisting cardiovascular disease.

This case highlights the relationship between T2DM and HF. We also show how the use of empagliflozin may have helped manage the patient’s undiagnosed HF and how its discontinuation luckily unmasked it. Routine evaluation for HF in patients with T2DM is not done, but likely there are patients who would benefit, especially given the strong, albeit less known, association between these 2 conditions.

Further studies are needed to determine the type of patients who would benefit most from HF screening. For now, the best practice is to obtain a complete medical history that includes current and recently discontinued medications as well a thorough physical examination for signs of fluid overload and cardiovascular compromise. Patients who may have signs concerning for HF can have appropriate testing and intervention.

Conclusions

SGLT2 inhibitors have been shown to have a role in the management of HF in patients with T2DM. There is a risk of exacerbation or unmasking of HF when discontinuing SGLT2 inhibitors. To our knowledge, this is the first paper describing the discovery of HF following interruption of SGLT2 inhibitor treatment. The clinician and patient should monitor for signs and symptoms of fluid overload when stopping therapy. Further research into the benefits of a more comprehensive evaluation is needed.