Alzheimer's & Cognition

Clinical trials represent future hope for patients seeking better care, and there is no disease more in need of better care than Alzheimer’s disease. While death rates among most cancers, as well as heart disease, HIV-related illness, and other categories, have declined in the past decade, there has been no progress for Alzheimer’s disease. Better health and wellness overall may be having a beneficial effect that has produced a reduction in age-adjusted dementia rates, but with the aging of the population there are a greater absolute number of dementia cases than ever before, and that number is expected to continue rising. Finding a disease-modifying therapy seems to be the best hope for changing this dim outlook. Clinical trials intend to do just that but are hampered by patient enrollment rates that remain low. Far fewer eligible patients enroll than are needed, causing studies to take longer to complete, driving up their costs and essentially slowing progress. There is a need to increase patient enrollment, and there has been a variety of efforts intended to address this, not the least of which has been an explosion of media coverage of Alzheimer’s disease.

The Global Alzheimer’s Platform (GAP) Foundation, a nonprofit, self-described patient-centric entity dedicated to reducing the time and cost of Alzheimer’s disease clinical trials, recently announced an initiative to increase participation in Alzheimer’s clinical trials by supporting and collaborating with “memory fitness programs” through select Medicare Advantage plans. At worst, this seems a harmless way to increase attention and hopefully interest in clinical trial participation. At best, this may be a cost-effective way to increase enrollment and even improve dementia care. Dementia is notoriously underdiagnosed, especially by overworked, busy primary care providers who simply lack the time to perform the time-consuming testing that is typically required to diagnose and follow such patients.

There are some caveats to consider. First, memory fitness programs are of dubious benefit. They generally fit the description of being harmless, but there is little compelling evidence that they preserve or improve memory.

Second, enrollment in a clinical trial, for a patient, is not always a winning proposition. To date, there has been little success and in the absence of benefit, any downside – even if simply an inconvenience – is a net negative. Recently at the 2018 Clinical Trials on Alzheimer’s Disease meeting, Merck reported that patients with mild cognitive impairment receiving active treatment in the BACE1 inhibitor verubecestat trial actually declined at a more rapid rate than did those on placebo. While the absolute difference was small, and one could argue whether it was clinically significant or simply a random occurrence, it was a reminder that intervention with an experimental agent is not necessarily benign.

Third, Medicare Advantage plans, while popular in some circles, are not considered advantageous to providers so that the proliferation of inadequate reimbursement will potentially fuel the accelerating number of providers who opt out of insurance plans altogether. This is not necessarily an issue for the GAP Foundation specifically but is nonetheless an issue for anything that promotes MA plans).

Finally, it remains important to help patients and families maintain a positive outlook, especially when we have nothing better to offer. Alzheimer’s disease is not a death sentence for every patient affected. While many have difficult and heartbreaking courses, some have slowly progressive courses with relatively little impairment for an extended period of time. There are also the dementia-phobic, cognitively unimpaired individuals (or who simply have normal age-associated cognitive changes) in whom the continued drumbeat of dementia awareness and memory testing raises their paranoia ever higher. We treat deficits (or try to), but we have to live based on our preserved skills. The challenge clinicians must face with patients and families is how to maximize function while compensating for deficits and making sure that patients and families maintain their hope.

Dr. Caselli is professor of neurology at the Mayo Clinic Arizona in Scottsdale and associate director and clinical core director of the Arizona Alzheimer’s Disease Center.

Clinical trials represent future hope for patients seeking better care, and there is no disease more in need of better care than Alzheimer’s disease. While death rates among most cancers, as well as heart disease, HIV-related illness, and other categories, have declined in the past decade, there has been no progress for Alzheimer’s disease. Better health and wellness overall may be having a beneficial effect that has produced a reduction in age-adjusted dementia rates, but with the aging of the population there are a greater absolute number of dementia cases than ever before, and that number is expected to continue rising. Finding a disease-modifying therapy seems to be the best hope for changing this dim outlook. Clinical trials intend to do just that but are hampered by patient enrollment rates that remain low. Far fewer eligible patients enroll than are needed, causing studies to take longer to complete, driving up their costs and essentially slowing progress. There is a need to increase patient enrollment, and there has been a variety of efforts intended to address this, not the least of which has been an explosion of media coverage of Alzheimer’s disease.

The Global Alzheimer’s Platform (GAP) Foundation, a nonprofit, self-described patient-centric entity dedicated to reducing the time and cost of Alzheimer’s disease clinical trials, recently announced an initiative to increase participation in Alzheimer’s clinical trials by supporting and collaborating with “memory fitness programs” through select Medicare Advantage plans. At worst, this seems a harmless way to increase attention and hopefully interest in clinical trial participation. At best, this may be a cost-effective way to increase enrollment and even improve dementia care. Dementia is notoriously underdiagnosed, especially by overworked, busy primary care providers who simply lack the time to perform the time-consuming testing that is typically required to diagnose and follow such patients.

There are some caveats to consider. First, memory fitness programs are of dubious benefit. They generally fit the description of being harmless, but there is little compelling evidence that they preserve or improve memory.

Second, enrollment in a clinical trial, for a patient, is not always a winning proposition. To date, there has been little success and in the absence of benefit, any downside – even if simply an inconvenience – is a net negative. Recently at the 2018 Clinical Trials on Alzheimer’s Disease meeting, Merck reported that patients with mild cognitive impairment receiving active treatment in the BACE1 inhibitor verubecestat trial actually declined at a more rapid rate than did those on placebo. While the absolute difference was small, and one could argue whether it was clinically significant or simply a random occurrence, it was a reminder that intervention with an experimental agent is not necessarily benign.

Third, Medicare Advantage plans, while popular in some circles, are not considered advantageous to providers so that the proliferation of inadequate reimbursement will potentially fuel the accelerating number of providers who opt out of insurance plans altogether. This is not necessarily an issue for the GAP Foundation specifically but is nonetheless an issue for anything that promotes MA plans).

Finally, it remains important to help patients and families maintain a positive outlook, especially when we have nothing better to offer. Alzheimer’s disease is not a death sentence for every patient affected. While many have difficult and heartbreaking courses, some have slowly progressive courses with relatively little impairment for an extended period of time. There are also the dementia-phobic, cognitively unimpaired individuals (or who simply have normal age-associated cognitive changes) in whom the continued drumbeat of dementia awareness and memory testing raises their paranoia ever higher. We treat deficits (or try to), but we have to live based on our preserved skills. The challenge clinicians must face with patients and families is how to maximize function while compensating for deficits and making sure that patients and families maintain their hope.

Dr. Caselli is professor of neurology at the Mayo Clinic Arizona in Scottsdale and associate director and clinical core director of the Arizona Alzheimer’s Disease Center.

Clinical trials represent future hope for patients seeking better care, and there is no disease more in need of better care than Alzheimer’s disease. While death rates among most cancers, as well as heart disease, HIV-related illness, and other categories, have declined in the past decade, there has been no progress for Alzheimer’s disease. Better health and wellness overall may be having a beneficial effect that has produced a reduction in age-adjusted dementia rates, but with the aging of the population there are a greater absolute number of dementia cases than ever before, and that number is expected to continue rising. Finding a disease-modifying therapy seems to be the best hope for changing this dim outlook. Clinical trials intend to do just that but are hampered by patient enrollment rates that remain low. Far fewer eligible patients enroll than are needed, causing studies to take longer to complete, driving up their costs and essentially slowing progress. There is a need to increase patient enrollment, and there has been a variety of efforts intended to address this, not the least of which has been an explosion of media coverage of Alzheimer’s disease.

The Global Alzheimer’s Platform (GAP) Foundation, a nonprofit, self-described patient-centric entity dedicated to reducing the time and cost of Alzheimer’s disease clinical trials, recently announced an initiative to increase participation in Alzheimer’s clinical trials by supporting and collaborating with “memory fitness programs” through select Medicare Advantage plans. At worst, this seems a harmless way to increase attention and hopefully interest in clinical trial participation. At best, this may be a cost-effective way to increase enrollment and even improve dementia care. Dementia is notoriously underdiagnosed, especially by overworked, busy primary care providers who simply lack the time to perform the time-consuming testing that is typically required to diagnose and follow such patients.

There are some caveats to consider. First, memory fitness programs are of dubious benefit. They generally fit the description of being harmless, but there is little compelling evidence that they preserve or improve memory.

Second, enrollment in a clinical trial, for a patient, is not always a winning proposition. To date, there has been little success and in the absence of benefit, any downside – even if simply an inconvenience – is a net negative. Recently at the 2018 Clinical Trials on Alzheimer’s Disease meeting, Merck reported that patients with mild cognitive impairment receiving active treatment in the BACE1 inhibitor verubecestat trial actually declined at a more rapid rate than did those on placebo. While the absolute difference was small, and one could argue whether it was clinically significant or simply a random occurrence, it was a reminder that intervention with an experimental agent is not necessarily benign.

Third, Medicare Advantage plans, while popular in some circles, are not considered advantageous to providers so that the proliferation of inadequate reimbursement will potentially fuel the accelerating number of providers who opt out of insurance plans altogether. This is not necessarily an issue for the GAP Foundation specifically but is nonetheless an issue for anything that promotes MA plans).

Finally, it remains important to help patients and families maintain a positive outlook, especially when we have nothing better to offer. Alzheimer’s disease is not a death sentence for every patient affected. While many have difficult and heartbreaking courses, some have slowly progressive courses with relatively little impairment for an extended period of time. There are also the dementia-phobic, cognitively unimpaired individuals (or who simply have normal age-associated cognitive changes) in whom the continued drumbeat of dementia awareness and memory testing raises their paranoia ever higher. We treat deficits (or try to), but we have to live based on our preserved skills. The challenge clinicians must face with patients and families is how to maximize function while compensating for deficits and making sure that patients and families maintain their hope.

Dr. Caselli is professor of neurology at the Mayo Clinic Arizona in Scottsdale and associate director and clinical core director of the Arizona Alzheimer’s Disease Center.

A recently developed blood-based signature can help predict the status of an early Alzheimer’s disease risk indicator with high accuracy, investigators are reporting.

Courtesy NIH

By analyzing as few as four proteins, the machine learning-derived test can predict the status of cerebrospinal fluid (CSF) amyloid beta_1-42 (Abeta1-42), according to Noel G. Faux, PHD, of IBM Australia and the University of Melbourne, and co-investigators.

While shifts in Abeta1-42 may signal the presence of disease long before significant cognitive decline is clinically apparent, collection of CSF is highly invasive and expensive, Faux and investigators said in their report.

By contrast, blood biomarkers could prove to be a useful alternative not only to invasive lumbar punctures, they said, but also to the positron emission tomography (PET) evaluation of Abeta1-42, which is expensive and limited in some regions.

“In conjunction with biomarkers for neocortical amyloid burden, the CSF Abeta1-42biomarkers presented in this work may help yield a cheap, non-invasive tool for both improving clinical trials targeting amyloid and population screening,” Dr. Faux and co-authors said in Scientific Reports.

Dr. Faux and colleagues used a Random Forest approach to build models for CSF Abeta1-42 using blood biomarkers and other variables.

They found that a model incorporating age, APOEe4 carrier status, and a number of plasma protein levels predicted Abeta1-42 normal/abnormalstatus with an AUC, sensitivity and specificity of 0.84, 0.78 and 0.73 respectively.

In a model they said was more suitable for clinical application, they narrowed down the variables to 4 plasma analytes and APOEe4 carrier status, which had an AUC, sensitivity, and specificity of 0.81, 0.81 and 0.64 respectively.

They validated the models on a cohort of individuals in the Alzheimer’s Disease Neuroimaging Initiative (ADNI), a large, longitudinal, multicenter study.

Patients with mild cognitive impairment with predicted abnormal CSF Abeta1-42 levels indeed did transition to a diagnosis of Alzheimer’s disease more quickly than those with predicted normal levels, according to investigators.

That helps provide “strong evidence” that the blood-based model is generalizable, robust, and could help stratify patients based on risk of progressing to Alzheimer’s disease, they said in their report.

Dr. Faux and colleagues declared no conflicts of interest related to the research.
 

SOURCE: Goudey B, et al. Sci Rep. 2019 Mar 10. doi: 10.1101/190207v3.

A recently developed blood-based signature can help predict the status of an early Alzheimer’s disease risk indicator with high accuracy, investigators are reporting.

Courtesy NIH

By analyzing as few as four proteins, the machine learning-derived test can predict the status of cerebrospinal fluid (CSF) amyloid beta_1-42 (Abeta1-42), according to Noel G. Faux, PHD, of IBM Australia and the University of Melbourne, and co-investigators.

While shifts in Abeta1-42 may signal the presence of disease long before significant cognitive decline is clinically apparent, collection of CSF is highly invasive and expensive, Faux and investigators said in their report.

By contrast, blood biomarkers could prove to be a useful alternative not only to invasive lumbar punctures, they said, but also to the positron emission tomography (PET) evaluation of Abeta1-42, which is expensive and limited in some regions.

“In conjunction with biomarkers for neocortical amyloid burden, the CSF Abeta1-42biomarkers presented in this work may help yield a cheap, non-invasive tool for both improving clinical trials targeting amyloid and population screening,” Dr. Faux and co-authors said in Scientific Reports.

Dr. Faux and colleagues used a Random Forest approach to build models for CSF Abeta1-42 using blood biomarkers and other variables.

They found that a model incorporating age, APOEe4 carrier status, and a number of plasma protein levels predicted Abeta1-42 normal/abnormalstatus with an AUC, sensitivity and specificity of 0.84, 0.78 and 0.73 respectively.

In a model they said was more suitable for clinical application, they narrowed down the variables to 4 plasma analytes and APOEe4 carrier status, which had an AUC, sensitivity, and specificity of 0.81, 0.81 and 0.64 respectively.

They validated the models on a cohort of individuals in the Alzheimer’s Disease Neuroimaging Initiative (ADNI), a large, longitudinal, multicenter study.

Patients with mild cognitive impairment with predicted abnormal CSF Abeta1-42 levels indeed did transition to a diagnosis of Alzheimer’s disease more quickly than those with predicted normal levels, according to investigators.

That helps provide “strong evidence” that the blood-based model is generalizable, robust, and could help stratify patients based on risk of progressing to Alzheimer’s disease, they said in their report.

Dr. Faux and colleagues declared no conflicts of interest related to the research.
 

SOURCE: Goudey B, et al. Sci Rep. 2019 Mar 10. doi: 10.1101/190207v3.

A recently developed blood-based signature can help predict the status of an early Alzheimer’s disease risk indicator with high accuracy, investigators are reporting.

Courtesy NIH

By analyzing as few as four proteins, the machine learning-derived test can predict the status of cerebrospinal fluid (CSF) amyloid beta_1-42 (Abeta1-42), according to Noel G. Faux, PHD, of IBM Australia and the University of Melbourne, and co-investigators.

While shifts in Abeta1-42 may signal the presence of disease long before significant cognitive decline is clinically apparent, collection of CSF is highly invasive and expensive, Faux and investigators said in their report.

By contrast, blood biomarkers could prove to be a useful alternative not only to invasive lumbar punctures, they said, but also to the positron emission tomography (PET) evaluation of Abeta1-42, which is expensive and limited in some regions.

“In conjunction with biomarkers for neocortical amyloid burden, the CSF Abeta1-42biomarkers presented in this work may help yield a cheap, non-invasive tool for both improving clinical trials targeting amyloid and population screening,” Dr. Faux and co-authors said in Scientific Reports.

Dr. Faux and colleagues used a Random Forest approach to build models for CSF Abeta1-42 using blood biomarkers and other variables.

They found that a model incorporating age, APOEe4 carrier status, and a number of plasma protein levels predicted Abeta1-42 normal/abnormalstatus with an AUC, sensitivity and specificity of 0.84, 0.78 and 0.73 respectively.

In a model they said was more suitable for clinical application, they narrowed down the variables to 4 plasma analytes and APOEe4 carrier status, which had an AUC, sensitivity, and specificity of 0.81, 0.81 and 0.64 respectively.

They validated the models on a cohort of individuals in the Alzheimer’s Disease Neuroimaging Initiative (ADNI), a large, longitudinal, multicenter study.

Patients with mild cognitive impairment with predicted abnormal CSF Abeta1-42 levels indeed did transition to a diagnosis of Alzheimer’s disease more quickly than those with predicted normal levels, according to investigators.

That helps provide “strong evidence” that the blood-based model is generalizable, robust, and could help stratify patients based on risk of progressing to Alzheimer’s disease, they said in their report.

Dr. Faux and colleagues declared no conflicts of interest related to the research.
 

SOURCE: Goudey B, et al. Sci Rep. 2019 Mar 10. doi: 10.1101/190207v3.

The total tau level in blood plasma appears to predict both onset and progression of dementia and could be used to help refine research cohorts.

Kheng Guan Toh/Thinkstock

Blood samples from two large dementia research cohorts confirmed the finding: Each standard deviation in plasma tau above the median is associated with a 29% greater risk of incident all-cause dementia and a 35%increase in the risk of incident Alzheimer’s disease, Matthew P. Pase, PhD and colleagues wrote in JAMA Neurology. It also correlated positively with some neuropathological aspects of dementia: smaller hippocampus and a higher burden of neurofibrillary tangles in the medial temporal lobe, said Dr. Pase of The Florey Institute for Neuroscience and Mental Health. Victoria, Australia.

Plasma tau isn’t the highly sought Holy Grail of a simple Alzheimer’s blood test. But the finding could benefit the research world. As a study entry criteria, it could substantially decrease the number of subjects needed to validate an outcome of either all-cause dementia or Alzheimer’s disease. Abnormal tau is also a required finding for an Alzheimer’s diagnosis in revised NIA-AA Research Framework. And, the authors noted, although plasma tau wasn’t quite as accurate a predictor as CSF tau, a needle in the arm would be much more acceptable to many more patients than a lumbar puncture.

“Whereas we do not expect plasma t-tau cutoffs to enhance diagnostic certainty for any single patient, our results suggest that plasma t-tau could be associated with improved risk stratification at a population level, targeting persons for inclusion in prevention trials, thus improving the power and precision of clinical trials and potentially accelerating therapeutic pipelines and drug discovery,” the team wrote.

The study drew on stored plasma samples from subjects enrolled in the Framingham Heart Study (1,453) and the Memento study, a multicenter cohort of persons with mild cognitive impairment or subjective cognitive complaints recruited from memory clinics across France (367).

The Framingham cohort was followed for up to 10 years between baseline examination to incident event (median 6 years).

Over that time, 134 (9.2%) cases of dementia developed; most of these (105) were due possible, probable, or definite Alzheimer’s.

Plasma tau levels rose linearly as the cohort aged. Higher plasma t-tau levels were associated with proven AD risk factors, including female sex, lower education, and higher vascular risk factors. They did not differ by apolipoprotein epsilon 4 status (APOEe4).

After adjusting for age and sex, each stand deviation unit increase in the log of tau was associated with a 29% greater risk of incident all-cause dementia, and a 35% increase in the risk of incident Alzheimer’s dementia. Subjects with tau levels above the median had a 62% increased risk of all-cause dementia and a 76% greater risk of AD. Adding APOEe4 status and vascular risk factors to the analysis didn’t alter the associations.

“Plasma t-tau level improved risk discrimination for all dementia and AD dementia beyond age and sex,” the investigators wrote. “[It] was associated with improved risk discrimination … in both APOEe4 carriers and noncarriers.”

In a hypothetical 5-year clinical trial, enrolling subjects with total plasma tau greater than the median could reduce the estimated necessary sample size by 38% for an outcome of all-cause dementia and by 50% for one of Alzheimer’s. Selecting those with both elevated plasma tau and APOEe4 carriage could reduce the required sample by 69% for all-cause dementia outcomes and by 80% for Alzheimer’s outcomes.

In the neuropathologic study, each standard deviation unit increase was associated with more neurofibrillary tangles in the medial temporal lobe, more microinfarcts, and smaller hippocampal volume. There was no association with amyloid plaque in any brain region.

Subjects in the Memento study had a meant of 4 years of follow-up. Over that time, there were 76 cases of incident dementia, 55 of which were probable Alzheimer’s.

Each standard deviation unit increase was associated with a nonsignificant 14% greater risk of all-cause dementia and a significant 54% increase in the risk of incident Alzheimer’s.

CSF was drawn on the same day as plasma in 140 of these subjects. The addition of CSF boosted the predictive value; each standard deviation increase more than doubled the risk of both Alzheimer’s (HR 2.33). Each standard deviation unit increase in CSF t-tau increased the risk by 2.14.

“Plasma t-tau was weakly correlated with CSF t-tau in our study. This finding is consistent

with previous studies showing that the associations of plasma t-tau with CSF t-tau have been weak or nonexistent,” the authors wrote. But, “Despite a weak correlation between plasma and CSF t-tau, plasma t-tau was at least as strongly associated with the development of incident AD dementia.”

“Use of plasma t-tau in this manner could be likened to the measurement of the APOEe4 allele, which is not a biomarker of AD pathology providing diagnostic certainty for AD dementia but is still routinely used to power clinical trials by selecting at-risk individuals,” they concluded.

Dr. Pase had no financial disclosures.

[email protected]

SOURCE: Pase, M et al JAMA Neurol 2019 doi:10.1001/jamaneurol.2018.4666

The total tau level in blood plasma appears to predict both onset and progression of dementia and could be used to help refine research cohorts.

Kheng Guan Toh/Thinkstock

Blood samples from two large dementia research cohorts confirmed the finding: Each standard deviation in plasma tau above the median is associated with a 29% greater risk of incident all-cause dementia and a 35%increase in the risk of incident Alzheimer’s disease, Matthew P. Pase, PhD and colleagues wrote in JAMA Neurology. It also correlated positively with some neuropathological aspects of dementia: smaller hippocampus and a higher burden of neurofibrillary tangles in the medial temporal lobe, said Dr. Pase of The Florey Institute for Neuroscience and Mental Health. Victoria, Australia.

Plasma tau isn’t the highly sought Holy Grail of a simple Alzheimer’s blood test. But the finding could benefit the research world. As a study entry criteria, it could substantially decrease the number of subjects needed to validate an outcome of either all-cause dementia or Alzheimer’s disease. Abnormal tau is also a required finding for an Alzheimer’s diagnosis in revised NIA-AA Research Framework. And, the authors noted, although plasma tau wasn’t quite as accurate a predictor as CSF tau, a needle in the arm would be much more acceptable to many more patients than a lumbar puncture.

“Whereas we do not expect plasma t-tau cutoffs to enhance diagnostic certainty for any single patient, our results suggest that plasma t-tau could be associated with improved risk stratification at a population level, targeting persons for inclusion in prevention trials, thus improving the power and precision of clinical trials and potentially accelerating therapeutic pipelines and drug discovery,” the team wrote.

The study drew on stored plasma samples from subjects enrolled in the Framingham Heart Study (1,453) and the Memento study, a multicenter cohort of persons with mild cognitive impairment or subjective cognitive complaints recruited from memory clinics across France (367).

The Framingham cohort was followed for up to 10 years between baseline examination to incident event (median 6 years).

Over that time, 134 (9.2%) cases of dementia developed; most of these (105) were due possible, probable, or definite Alzheimer’s.

Plasma tau levels rose linearly as the cohort aged. Higher plasma t-tau levels were associated with proven AD risk factors, including female sex, lower education, and higher vascular risk factors. They did not differ by apolipoprotein epsilon 4 status (APOEe4).

After adjusting for age and sex, each stand deviation unit increase in the log of tau was associated with a 29% greater risk of incident all-cause dementia, and a 35% increase in the risk of incident Alzheimer’s dementia. Subjects with tau levels above the median had a 62% increased risk of all-cause dementia and a 76% greater risk of AD. Adding APOEe4 status and vascular risk factors to the analysis didn’t alter the associations.

“Plasma t-tau level improved risk discrimination for all dementia and AD dementia beyond age and sex,” the investigators wrote. “[It] was associated with improved risk discrimination … in both APOEe4 carriers and noncarriers.”

In a hypothetical 5-year clinical trial, enrolling subjects with total plasma tau greater than the median could reduce the estimated necessary sample size by 38% for an outcome of all-cause dementia and by 50% for one of Alzheimer’s. Selecting those with both elevated plasma tau and APOEe4 carriage could reduce the required sample by 69% for all-cause dementia outcomes and by 80% for Alzheimer’s outcomes.

In the neuropathologic study, each standard deviation unit increase was associated with more neurofibrillary tangles in the medial temporal lobe, more microinfarcts, and smaller hippocampal volume. There was no association with amyloid plaque in any brain region.

Subjects in the Memento study had a meant of 4 years of follow-up. Over that time, there were 76 cases of incident dementia, 55 of which were probable Alzheimer’s.

Each standard deviation unit increase was associated with a nonsignificant 14% greater risk of all-cause dementia and a significant 54% increase in the risk of incident Alzheimer’s.

CSF was drawn on the same day as plasma in 140 of these subjects. The addition of CSF boosted the predictive value; each standard deviation increase more than doubled the risk of both Alzheimer’s (HR 2.33). Each standard deviation unit increase in CSF t-tau increased the risk by 2.14.

“Plasma t-tau was weakly correlated with CSF t-tau in our study. This finding is consistent

with previous studies showing that the associations of plasma t-tau with CSF t-tau have been weak or nonexistent,” the authors wrote. But, “Despite a weak correlation between plasma and CSF t-tau, plasma t-tau was at least as strongly associated with the development of incident AD dementia.”

“Use of plasma t-tau in this manner could be likened to the measurement of the APOEe4 allele, which is not a biomarker of AD pathology providing diagnostic certainty for AD dementia but is still routinely used to power clinical trials by selecting at-risk individuals,” they concluded.

Dr. Pase had no financial disclosures.

[email protected]

SOURCE: Pase, M et al JAMA Neurol 2019 doi:10.1001/jamaneurol.2018.4666

The total tau level in blood plasma appears to predict both onset and progression of dementia and could be used to help refine research cohorts.

Kheng Guan Toh/Thinkstock

Blood samples from two large dementia research cohorts confirmed the finding: Each standard deviation in plasma tau above the median is associated with a 29% greater risk of incident all-cause dementia and a 35%increase in the risk of incident Alzheimer’s disease, Matthew P. Pase, PhD and colleagues wrote in JAMA Neurology. It also correlated positively with some neuropathological aspects of dementia: smaller hippocampus and a higher burden of neurofibrillary tangles in the medial temporal lobe, said Dr. Pase of The Florey Institute for Neuroscience and Mental Health. Victoria, Australia.

Plasma tau isn’t the highly sought Holy Grail of a simple Alzheimer’s blood test. But the finding could benefit the research world. As a study entry criteria, it could substantially decrease the number of subjects needed to validate an outcome of either all-cause dementia or Alzheimer’s disease. Abnormal tau is also a required finding for an Alzheimer’s diagnosis in revised NIA-AA Research Framework. And, the authors noted, although plasma tau wasn’t quite as accurate a predictor as CSF tau, a needle in the arm would be much more acceptable to many more patients than a lumbar puncture.

“Whereas we do not expect plasma t-tau cutoffs to enhance diagnostic certainty for any single patient, our results suggest that plasma t-tau could be associated with improved risk stratification at a population level, targeting persons for inclusion in prevention trials, thus improving the power and precision of clinical trials and potentially accelerating therapeutic pipelines and drug discovery,” the team wrote.

The study drew on stored plasma samples from subjects enrolled in the Framingham Heart Study (1,453) and the Memento study, a multicenter cohort of persons with mild cognitive impairment or subjective cognitive complaints recruited from memory clinics across France (367).

The Framingham cohort was followed for up to 10 years between baseline examination to incident event (median 6 years).

Over that time, 134 (9.2%) cases of dementia developed; most of these (105) were due possible, probable, or definite Alzheimer’s.

Plasma tau levels rose linearly as the cohort aged. Higher plasma t-tau levels were associated with proven AD risk factors, including female sex, lower education, and higher vascular risk factors. They did not differ by apolipoprotein epsilon 4 status (APOEe4).

After adjusting for age and sex, each stand deviation unit increase in the log of tau was associated with a 29% greater risk of incident all-cause dementia, and a 35% increase in the risk of incident Alzheimer’s dementia. Subjects with tau levels above the median had a 62% increased risk of all-cause dementia and a 76% greater risk of AD. Adding APOEe4 status and vascular risk factors to the analysis didn’t alter the associations.

“Plasma t-tau level improved risk discrimination for all dementia and AD dementia beyond age and sex,” the investigators wrote. “[It] was associated with improved risk discrimination … in both APOEe4 carriers and noncarriers.”

In a hypothetical 5-year clinical trial, enrolling subjects with total plasma tau greater than the median could reduce the estimated necessary sample size by 38% for an outcome of all-cause dementia and by 50% for one of Alzheimer’s. Selecting those with both elevated plasma tau and APOEe4 carriage could reduce the required sample by 69% for all-cause dementia outcomes and by 80% for Alzheimer’s outcomes.

In the neuropathologic study, each standard deviation unit increase was associated with more neurofibrillary tangles in the medial temporal lobe, more microinfarcts, and smaller hippocampal volume. There was no association with amyloid plaque in any brain region.

Subjects in the Memento study had a meant of 4 years of follow-up. Over that time, there were 76 cases of incident dementia, 55 of which were probable Alzheimer’s.

Each standard deviation unit increase was associated with a nonsignificant 14% greater risk of all-cause dementia and a significant 54% increase in the risk of incident Alzheimer’s.

CSF was drawn on the same day as plasma in 140 of these subjects. The addition of CSF boosted the predictive value; each standard deviation increase more than doubled the risk of both Alzheimer’s (HR 2.33). Each standard deviation unit increase in CSF t-tau increased the risk by 2.14.

“Plasma t-tau was weakly correlated with CSF t-tau in our study. This finding is consistent

with previous studies showing that the associations of plasma t-tau with CSF t-tau have been weak or nonexistent,” the authors wrote. But, “Despite a weak correlation between plasma and CSF t-tau, plasma t-tau was at least as strongly associated with the development of incident AD dementia.”

“Use of plasma t-tau in this manner could be likened to the measurement of the APOEe4 allele, which is not a biomarker of AD pathology providing diagnostic certainty for AD dementia but is still routinely used to power clinical trials by selecting at-risk individuals,” they concluded.

Dr. Pase had no financial disclosures.

[email protected]

SOURCE: Pase, M et al JAMA Neurol 2019 doi:10.1001/jamaneurol.2018.4666

HONOLULU – Covert strokes are relatively common in elderly patients who undergo noncardiac surgery, with a 7% incidence among a group of prospectively followed but generally unselected patients in a multicenter, international study.

By definition, these covert strokes were acutely asymptomatic, but showed evidence of clinical effects during the subsequent year. Twelve months after surgery, patients with acute, perioperative covert strokes found by systematic collection of postoperative MRI brain scans had a twofold increased rate of cognitive decline and a greater than twofold increased rate of delirium, compared with the patients who did not have evidence of a covert stroke, Marko Mrkobrada, MD, said at the International Stroke Conference sponsored by the American Heart Association.

The message from these findings is that, when elderly patients exhibit confusion or delirium after noncardiac surgery, their physicians should have a high index of suspicion that a covert stroke may have occurred, Dr. Mrkobrada said in a video interview. It’s possible that typical stroke symptoms do not appear in many of the covert stroke patients because they are masked in the immediate postoperative period, he added.

Right now, the only way to screen for a covert stroke is with a brain MR, a test that generally costs several hundred dollars, which is too expensive for routine screening. Dr. Mrkobrada said that his team hopes further study will identify a biomarker that can flag patients with a covert stroke at a lower cost. For example, colleagues of Dr. Mrkobrada have successfully used high-sensitivity troponin T, a biomarker of myocardial injury, to identify patients who have myocardial injury after noncardiac surgery (MINS; JAMA. 2017 April 25;371[16]:1642-51). Study results also established that treating MINS patients with dabigatran improved their long-term clinical outcomes (Lancet. 2018 June 9;391[10137]:2325-34).

Covert stroke after noncardiac surgery “is the same concept” as MINS, said Dr. Mrkobrada, a researcher at the London Health Sciences Centre in Canada. “We find strokes that do not get picked up after noncardiac surgery just like MIs that are not picked up,” he said. It’s also possible that certain interventions may improve outcomes in patients with covert strokes, just as they have helped MINS patients, he suggested. Potentially helpful interventions could include aspirin, a statin, and improved blood pressure control. A major goal for his research group is finding a biomarker that makes diagnosing covert stroke as easy as using high sensitivity troponin T to diagnose MINS.

The NeuroVISION (Detection and Neurological Impact of Cerebrovascular Events In Noncardiac Surgery Patients: A Cohort EvaluatioN) study enrolled and tested 1,114 people aged 65 years or older scheduled for elective noncardiac surgery anticipated to keep them hospitalized for at least 2 days at any of 12 participating centers in nine countries. Patients underwent cognitive function testing before surgery and had a brain MR scan 2-9 days after surgery, and they were excluded if they developed an overt stroke prior to the scan. Patients underwent a second round of cognitive testing a year after surgery. Patients averaged 73 years old.

The screening MR scans identified covert strokes in 78 of the study subjects (7%). The 1-year cognitive tests showed measurable drops in cognitive function in 42% of those who had experience covert strokes and in 29% of everyone else. Those rates translated to a doubled odds ratio for cognitive decline after covert stroke, compared with people without covert stroke after adjustment for baseline between-group differences, a highly statistically significant between-group difference for the study’s primary endpoint. Delirium occurred 2.2-fold more often in the covert stroke patients after adjustment, and overt strokes during 1-year follow-up were 4.1-fold more common patients who’d experienced a covert stroke, compared with everyone else, after adjustment, Dr. Mrkobrada reported. NeuroVISION is the first large-scale study to assess the incidence and associations of covert strokes after noncardiac surgery, he noted.

[email protected]

SOURCE: Mrkobrada M. ISC 2019, Late-Breaking Abstract LB18.

HONOLULU – Covert strokes are relatively common in elderly patients who undergo noncardiac surgery, with a 7% incidence among a group of prospectively followed but generally unselected patients in a multicenter, international study.

By definition, these covert strokes were acutely asymptomatic, but showed evidence of clinical effects during the subsequent year. Twelve months after surgery, patients with acute, perioperative covert strokes found by systematic collection of postoperative MRI brain scans had a twofold increased rate of cognitive decline and a greater than twofold increased rate of delirium, compared with the patients who did not have evidence of a covert stroke, Marko Mrkobrada, MD, said at the International Stroke Conference sponsored by the American Heart Association.

The message from these findings is that, when elderly patients exhibit confusion or delirium after noncardiac surgery, their physicians should have a high index of suspicion that a covert stroke may have occurred, Dr. Mrkobrada said in a video interview. It’s possible that typical stroke symptoms do not appear in many of the covert stroke patients because they are masked in the immediate postoperative period, he added.

Right now, the only way to screen for a covert stroke is with a brain MR, a test that generally costs several hundred dollars, which is too expensive for routine screening. Dr. Mrkobrada said that his team hopes further study will identify a biomarker that can flag patients with a covert stroke at a lower cost. For example, colleagues of Dr. Mrkobrada have successfully used high-sensitivity troponin T, a biomarker of myocardial injury, to identify patients who have myocardial injury after noncardiac surgery (MINS; JAMA. 2017 April 25;371[16]:1642-51). Study results also established that treating MINS patients with dabigatran improved their long-term clinical outcomes (Lancet. 2018 June 9;391[10137]:2325-34).

Covert stroke after noncardiac surgery “is the same concept” as MINS, said Dr. Mrkobrada, a researcher at the London Health Sciences Centre in Canada. “We find strokes that do not get picked up after noncardiac surgery just like MIs that are not picked up,” he said. It’s also possible that certain interventions may improve outcomes in patients with covert strokes, just as they have helped MINS patients, he suggested. Potentially helpful interventions could include aspirin, a statin, and improved blood pressure control. A major goal for his research group is finding a biomarker that makes diagnosing covert stroke as easy as using high sensitivity troponin T to diagnose MINS.

The NeuroVISION (Detection and Neurological Impact of Cerebrovascular Events In Noncardiac Surgery Patients: A Cohort EvaluatioN) study enrolled and tested 1,114 people aged 65 years or older scheduled for elective noncardiac surgery anticipated to keep them hospitalized for at least 2 days at any of 12 participating centers in nine countries. Patients underwent cognitive function testing before surgery and had a brain MR scan 2-9 days after surgery, and they were excluded if they developed an overt stroke prior to the scan. Patients underwent a second round of cognitive testing a year after surgery. Patients averaged 73 years old.

The screening MR scans identified covert strokes in 78 of the study subjects (7%). The 1-year cognitive tests showed measurable drops in cognitive function in 42% of those who had experience covert strokes and in 29% of everyone else. Those rates translated to a doubled odds ratio for cognitive decline after covert stroke, compared with people without covert stroke after adjustment for baseline between-group differences, a highly statistically significant between-group difference for the study’s primary endpoint. Delirium occurred 2.2-fold more often in the covert stroke patients after adjustment, and overt strokes during 1-year follow-up were 4.1-fold more common patients who’d experienced a covert stroke, compared with everyone else, after adjustment, Dr. Mrkobrada reported. NeuroVISION is the first large-scale study to assess the incidence and associations of covert strokes after noncardiac surgery, he noted.

[email protected]

SOURCE: Mrkobrada M. ISC 2019, Late-Breaking Abstract LB18.

HONOLULU – Covert strokes are relatively common in elderly patients who undergo noncardiac surgery, with a 7% incidence among a group of prospectively followed but generally unselected patients in a multicenter, international study.

By definition, these covert strokes were acutely asymptomatic, but showed evidence of clinical effects during the subsequent year. Twelve months after surgery, patients with acute, perioperative covert strokes found by systematic collection of postoperative MRI brain scans had a twofold increased rate of cognitive decline and a greater than twofold increased rate of delirium, compared with the patients who did not have evidence of a covert stroke, Marko Mrkobrada, MD, said at the International Stroke Conference sponsored by the American Heart Association.

The message from these findings is that, when elderly patients exhibit confusion or delirium after noncardiac surgery, their physicians should have a high index of suspicion that a covert stroke may have occurred, Dr. Mrkobrada said in a video interview. It’s possible that typical stroke symptoms do not appear in many of the covert stroke patients because they are masked in the immediate postoperative period, he added.

Right now, the only way to screen for a covert stroke is with a brain MR, a test that generally costs several hundred dollars, which is too expensive for routine screening. Dr. Mrkobrada said that his team hopes further study will identify a biomarker that can flag patients with a covert stroke at a lower cost. For example, colleagues of Dr. Mrkobrada have successfully used high-sensitivity troponin T, a biomarker of myocardial injury, to identify patients who have myocardial injury after noncardiac surgery (MINS; JAMA. 2017 April 25;371[16]:1642-51). Study results also established that treating MINS patients with dabigatran improved their long-term clinical outcomes (Lancet. 2018 June 9;391[10137]:2325-34).

Covert stroke after noncardiac surgery “is the same concept” as MINS, said Dr. Mrkobrada, a researcher at the London Health Sciences Centre in Canada. “We find strokes that do not get picked up after noncardiac surgery just like MIs that are not picked up,” he said. It’s also possible that certain interventions may improve outcomes in patients with covert strokes, just as they have helped MINS patients, he suggested. Potentially helpful interventions could include aspirin, a statin, and improved blood pressure control. A major goal for his research group is finding a biomarker that makes diagnosing covert stroke as easy as using high sensitivity troponin T to diagnose MINS.

The NeuroVISION (Detection and Neurological Impact of Cerebrovascular Events In Noncardiac Surgery Patients: A Cohort EvaluatioN) study enrolled and tested 1,114 people aged 65 years or older scheduled for elective noncardiac surgery anticipated to keep them hospitalized for at least 2 days at any of 12 participating centers in nine countries. Patients underwent cognitive function testing before surgery and had a brain MR scan 2-9 days after surgery, and they were excluded if they developed an overt stroke prior to the scan. Patients underwent a second round of cognitive testing a year after surgery. Patients averaged 73 years old.

The screening MR scans identified covert strokes in 78 of the study subjects (7%). The 1-year cognitive tests showed measurable drops in cognitive function in 42% of those who had experience covert strokes and in 29% of everyone else. Those rates translated to a doubled odds ratio for cognitive decline after covert stroke, compared with people without covert stroke after adjustment for baseline between-group differences, a highly statistically significant between-group difference for the study’s primary endpoint. Delirium occurred 2.2-fold more often in the covert stroke patients after adjustment, and overt strokes during 1-year follow-up were 4.1-fold more common patients who’d experienced a covert stroke, compared with everyone else, after adjustment, Dr. Mrkobrada reported. NeuroVISION is the first large-scale study to assess the incidence and associations of covert strokes after noncardiac surgery, he noted.

[email protected]

SOURCE: Mrkobrada M. ISC 2019, Late-Breaking Abstract LB18.

The Food and Drug Administration has issued warning letters to 12 companies and advisory letters to 5 companies illegally selling more than 58 products claiming to treat Alzheimer’s disease.

Wikimedia Commons/FitzColinGerald/Creative Commons License

The products, many of which are marketed as dietary supplements, are being sold in a variety of forms, including tablets, capsules, and oils. These drugs are either unapproved or mislabeled and claim to prevent, treat, or cure Alzheimer’s disease, as well as a number of other serious diseases and health conditions, in violation of the Federal Food, Drug, and Cosmetic Act.

“Alzheimer’s is a challenging disease that, unfortunately, has no cure. Any products making unproven drug claims could mislead consumers to believe that such therapies exist and keep them from accessing therapies that are known to help support the symptoms of the disease, or worse, as some fraudulent treatments can cause serious or even fatal injuries,” FDA Commissioner Scott Gottlieb, MD, said in a press release.

In an additional statement, Dr. Gottlieb detailed several new strategies for improving the safety and accuracy of dietary supplements, including efforts to more rapidly communicate to the public potential safety issues with dietary supplement products and to establish a flexible regulatory framework that promotes innovation and upholds product safety.

[email protected]

The Food and Drug Administration has issued warning letters to 12 companies and advisory letters to 5 companies illegally selling more than 58 products claiming to treat Alzheimer’s disease.

Wikimedia Commons/FitzColinGerald/Creative Commons License

The products, many of which are marketed as dietary supplements, are being sold in a variety of forms, including tablets, capsules, and oils. These drugs are either unapproved or mislabeled and claim to prevent, treat, or cure Alzheimer’s disease, as well as a number of other serious diseases and health conditions, in violation of the Federal Food, Drug, and Cosmetic Act.

“Alzheimer’s is a challenging disease that, unfortunately, has no cure. Any products making unproven drug claims could mislead consumers to believe that such therapies exist and keep them from accessing therapies that are known to help support the symptoms of the disease, or worse, as some fraudulent treatments can cause serious or even fatal injuries,” FDA Commissioner Scott Gottlieb, MD, said in a press release.

In an additional statement, Dr. Gottlieb detailed several new strategies for improving the safety and accuracy of dietary supplements, including efforts to more rapidly communicate to the public potential safety issues with dietary supplement products and to establish a flexible regulatory framework that promotes innovation and upholds product safety.

[email protected]

The Food and Drug Administration has issued warning letters to 12 companies and advisory letters to 5 companies illegally selling more than 58 products claiming to treat Alzheimer’s disease.

Wikimedia Commons/FitzColinGerald/Creative Commons License

The products, many of which are marketed as dietary supplements, are being sold in a variety of forms, including tablets, capsules, and oils. These drugs are either unapproved or mislabeled and claim to prevent, treat, or cure Alzheimer’s disease, as well as a number of other serious diseases and health conditions, in violation of the Federal Food, Drug, and Cosmetic Act.

“Alzheimer’s is a challenging disease that, unfortunately, has no cure. Any products making unproven drug claims could mislead consumers to believe that such therapies exist and keep them from accessing therapies that are known to help support the symptoms of the disease, or worse, as some fraudulent treatments can cause serious or even fatal injuries,” FDA Commissioner Scott Gottlieb, MD, said in a press release.

In an additional statement, Dr. Gottlieb detailed several new strategies for improving the safety and accuracy of dietary supplements, including efforts to more rapidly communicate to the public potential safety issues with dietary supplement products and to establish a flexible regulatory framework that promotes innovation and upholds product safety.

[email protected]

A plasma proteomic study has identified new biomarkers of Alzheimer’s disease pathology in cognitively unimpaired individuals, researchers reported in Science Advances.

Kheng guan Toh/Thinkstock

“To our knowledge, this is the first time that a multianalyte plasma biomarker panel for an Alzheimer’s disease–related phenotype has been found and independently replicated by a nontargeted mass spectrometry approach,” said Nicholas J. Ashton, PhD, of King’s College London and the University of Gothenburg in Sweden, and his research colleagues.

Blood-based measures that predict amyloid-beta burden in preclinical Alzheimer’s disease have the potential to help investigators conduct clinical trials and aid in diagnostic management. However, this novel approach needs to be validated and translated “to a simpler automated platform suitable for wider utility,” the investigators noted. In addition, it is unclear whether their classifier can track changes in amyloid-beta or differentiate between other diseases with amyloid-beta pathology.

Advances in mass spectrometry technology have renewed interest in the analysis of plasma proteins in patients with various diseases. To assess whether proteomic discovery in plasma can help predict amyloid-beta burden in preclinical Alzheimer’s disease, Dr. Ashton and his colleagues studied 238 cognitively unimpaired individuals from the Australian Imaging, Biomarker and Lifestyle Flagship Study of Ageing (AIBL) and the Kerr Anglican Retirement Village Initiative in Ageing Health (KARVIAH). The participants had undergone PET to determine their amyloid-beta status. In the AIBL cohort (n = 144), 100 participants were amyloid-beta negative, and 44 were amyloid-beta positive. In the KARVIAH cohort (n = 94), 59 participants were amyloid-beta negative, and 35 were amyloid-beta positive. There were significantly more APOE4 carriers in the amyloid-beta–positive groups than in the amyloid-beta–negative groups. In addition, the amyloid-beta–positive groups tended to be older.

A support vector machine analysis created classifiers predicting amyloid-beta positivity in the AIBL cohort using demographics, proteins, or both. The researchers then tested each classifier in the KARVIAH dataset to identify which model best predicted amyloid-beta positivity. The optimal model included 10 protein features (prothrombin, adhesion G protein–coupled receptor, amyloid-beta A4 protein, NGN2, DNAH10, REST, NfL, RPS6KA3, GPSM2, FHAD1) and two demographic features (APOE4 count and age).

The classifier achieved a testing area under the receiver operator characteristic curve of 0.891 in the KARVIAH cohort to predict amyloid-beta positivity in cognitively unimpaired individuals with a sensitivity of 0.78 and specificity of 0.77.

The 10 protein features “represent a diverse array of pathways,” and the highest ranked feature was the serine protease prothrombin, which is a precursor to thrombin, the authors noted. “Multiple lines of evidence support that cerebrovascular disease may play a role in AD and that amyloid-beta may be involved in thrombosis, fibrinolysis, and inflammation via its interaction with the coagulation cascade,” the researchers wrote.

Two of the biomarkers – amyloid-beta A4 protein and NfL – have been examined in prior research and had a greater effect size in a secondary analysis that included participants with mild cognitive impairment and Alzheimer’s disease. This finding confirms “their connection with the more established disease state,” Dr. Ashton and colleagues said. In the secondary analysis, the optimal classifier included one demographic factor (APOE4 count) and nine protein features, eight of which also were used in the cognitively unimpaired classifier.

The study was funded in part by the National Institute for Health Research Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King’s College London, and many authors reported additional research support from various institutions. One author is an employee of Johnson & Johnson and a named inventor on unrelated biomarker intellectual property owned by Proteome Science and King’s College London.

[email protected]

SOURCE: Ashton NJ et al. Sci Adv. 2019 Feb 6. doi: 10.1126/sciadv.aau7220.

A plasma proteomic study has identified new biomarkers of Alzheimer’s disease pathology in cognitively unimpaired individuals, researchers reported in Science Advances.

Kheng guan Toh/Thinkstock

“To our knowledge, this is the first time that a multianalyte plasma biomarker panel for an Alzheimer’s disease–related phenotype has been found and independently replicated by a nontargeted mass spectrometry approach,” said Nicholas J. Ashton, PhD, of King’s College London and the University of Gothenburg in Sweden, and his research colleagues.

Blood-based measures that predict amyloid-beta burden in preclinical Alzheimer’s disease have the potential to help investigators conduct clinical trials and aid in diagnostic management. However, this novel approach needs to be validated and translated “to a simpler automated platform suitable for wider utility,” the investigators noted. In addition, it is unclear whether their classifier can track changes in amyloid-beta or differentiate between other diseases with amyloid-beta pathology.

Advances in mass spectrometry technology have renewed interest in the analysis of plasma proteins in patients with various diseases. To assess whether proteomic discovery in plasma can help predict amyloid-beta burden in preclinical Alzheimer’s disease, Dr. Ashton and his colleagues studied 238 cognitively unimpaired individuals from the Australian Imaging, Biomarker and Lifestyle Flagship Study of Ageing (AIBL) and the Kerr Anglican Retirement Village Initiative in Ageing Health (KARVIAH). The participants had undergone PET to determine their amyloid-beta status. In the AIBL cohort (n = 144), 100 participants were amyloid-beta negative, and 44 were amyloid-beta positive. In the KARVIAH cohort (n = 94), 59 participants were amyloid-beta negative, and 35 were amyloid-beta positive. There were significantly more APOE4 carriers in the amyloid-beta–positive groups than in the amyloid-beta–negative groups. In addition, the amyloid-beta–positive groups tended to be older.

A support vector machine analysis created classifiers predicting amyloid-beta positivity in the AIBL cohort using demographics, proteins, or both. The researchers then tested each classifier in the KARVIAH dataset to identify which model best predicted amyloid-beta positivity. The optimal model included 10 protein features (prothrombin, adhesion G protein–coupled receptor, amyloid-beta A4 protein, NGN2, DNAH10, REST, NfL, RPS6KA3, GPSM2, FHAD1) and two demographic features (APOE4 count and age).

The classifier achieved a testing area under the receiver operator characteristic curve of 0.891 in the KARVIAH cohort to predict amyloid-beta positivity in cognitively unimpaired individuals with a sensitivity of 0.78 and specificity of 0.77.

The 10 protein features “represent a diverse array of pathways,” and the highest ranked feature was the serine protease prothrombin, which is a precursor to thrombin, the authors noted. “Multiple lines of evidence support that cerebrovascular disease may play a role in AD and that amyloid-beta may be involved in thrombosis, fibrinolysis, and inflammation via its interaction with the coagulation cascade,” the researchers wrote.

Two of the biomarkers – amyloid-beta A4 protein and NfL – have been examined in prior research and had a greater effect size in a secondary analysis that included participants with mild cognitive impairment and Alzheimer’s disease. This finding confirms “their connection with the more established disease state,” Dr. Ashton and colleagues said. In the secondary analysis, the optimal classifier included one demographic factor (APOE4 count) and nine protein features, eight of which also were used in the cognitively unimpaired classifier.

The study was funded in part by the National Institute for Health Research Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King’s College London, and many authors reported additional research support from various institutions. One author is an employee of Johnson & Johnson and a named inventor on unrelated biomarker intellectual property owned by Proteome Science and King’s College London.

[email protected]

SOURCE: Ashton NJ et al. Sci Adv. 2019 Feb 6. doi: 10.1126/sciadv.aau7220.

A plasma proteomic study has identified new biomarkers of Alzheimer’s disease pathology in cognitively unimpaired individuals, researchers reported in Science Advances.

Kheng guan Toh/Thinkstock

“To our knowledge, this is the first time that a multianalyte plasma biomarker panel for an Alzheimer’s disease–related phenotype has been found and independently replicated by a nontargeted mass spectrometry approach,” said Nicholas J. Ashton, PhD, of King’s College London and the University of Gothenburg in Sweden, and his research colleagues.

Blood-based measures that predict amyloid-beta burden in preclinical Alzheimer’s disease have the potential to help investigators conduct clinical trials and aid in diagnostic management. However, this novel approach needs to be validated and translated “to a simpler automated platform suitable for wider utility,” the investigators noted. In addition, it is unclear whether their classifier can track changes in amyloid-beta or differentiate between other diseases with amyloid-beta pathology.

Advances in mass spectrometry technology have renewed interest in the analysis of plasma proteins in patients with various diseases. To assess whether proteomic discovery in plasma can help predict amyloid-beta burden in preclinical Alzheimer’s disease, Dr. Ashton and his colleagues studied 238 cognitively unimpaired individuals from the Australian Imaging, Biomarker and Lifestyle Flagship Study of Ageing (AIBL) and the Kerr Anglican Retirement Village Initiative in Ageing Health (KARVIAH). The participants had undergone PET to determine their amyloid-beta status. In the AIBL cohort (n = 144), 100 participants were amyloid-beta negative, and 44 were amyloid-beta positive. In the KARVIAH cohort (n = 94), 59 participants were amyloid-beta negative, and 35 were amyloid-beta positive. There were significantly more APOE4 carriers in the amyloid-beta–positive groups than in the amyloid-beta–negative groups. In addition, the amyloid-beta–positive groups tended to be older.

A support vector machine analysis created classifiers predicting amyloid-beta positivity in the AIBL cohort using demographics, proteins, or both. The researchers then tested each classifier in the KARVIAH dataset to identify which model best predicted amyloid-beta positivity. The optimal model included 10 protein features (prothrombin, adhesion G protein–coupled receptor, amyloid-beta A4 protein, NGN2, DNAH10, REST, NfL, RPS6KA3, GPSM2, FHAD1) and two demographic features (APOE4 count and age).

The classifier achieved a testing area under the receiver operator characteristic curve of 0.891 in the KARVIAH cohort to predict amyloid-beta positivity in cognitively unimpaired individuals with a sensitivity of 0.78 and specificity of 0.77.

The 10 protein features “represent a diverse array of pathways,” and the highest ranked feature was the serine protease prothrombin, which is a precursor to thrombin, the authors noted. “Multiple lines of evidence support that cerebrovascular disease may play a role in AD and that amyloid-beta may be involved in thrombosis, fibrinolysis, and inflammation via its interaction with the coagulation cascade,” the researchers wrote.

Two of the biomarkers – amyloid-beta A4 protein and NfL – have been examined in prior research and had a greater effect size in a secondary analysis that included participants with mild cognitive impairment and Alzheimer’s disease. This finding confirms “their connection with the more established disease state,” Dr. Ashton and colleagues said. In the secondary analysis, the optimal classifier included one demographic factor (APOE4 count) and nine protein features, eight of which also were used in the cognitively unimpaired classifier.

The study was funded in part by the National Institute for Health Research Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King’s College London, and many authors reported additional research support from various institutions. One author is an employee of Johnson & Johnson and a named inventor on unrelated biomarker intellectual property owned by Proteome Science and King’s College London.

[email protected]

SOURCE: Ashton NJ et al. Sci Adv. 2019 Feb 6. doi: 10.1126/sciadv.aau7220.

Among adults with below-average fitness, aerobic exercise significantly improves executive function, according to a randomized clinical trial published in Neurology.

Chris Leary

“The effect of aerobic exercise on executive function was more pronounced as age increased, suggesting that it may mitigate age-related declines,” wrote Yaakov Stern, PhD, chief of cognitive neuroscience in the department of neurology at Columbia University, New York, and his research colleagues.

Research indicates that aerobic exercise provides cognitive benefits across the lifespan, but controlled exercise studies have been limited to elderly individuals, the researchers wrote. To examine the effects of aerobic exercise on cognitive function in younger, healthy adults, they conducted a randomized, parallel-group, observer-masked, community-based clinical trial. The investigators enrolled 132 cognitively normal people aged 20-67 years with aerobic capacity below the median. About 70% were women, and participants’ mean age was about 40 years.

“We hypothesized that aerobic exercise would have cognitive benefits, even in this younger age range, but that age might moderate the nature or degree of the benefit,” Dr. Stern and his colleagues wrote.

Participants were nonsmoking, habitual nonexercisers with below-average fitness by American Heart Association standards. The investigators used baseline aerobic capacity testing to establish safe exercise measures and heart rate targets.

The investigators randomly assigned participants to a group that performed aerobic exercise or to a control group that performed stretching and toning four times per week for 6 months. Outcome measures included domains of cognitive function (such as executive function, episodic memory, processing speed, language, and attention), everyday function, aerobic capacity, body mass index, and cortical thickness.

During a 2-week run-in period, participants went to their choice of five YMCA of New York City fitness centers three times per week. They had to attend at least five of these sessions to stay in the study. In both study arms, training sessions consisted of 10-15 minutes of warm-up and cooldown and 30-40 minutes of workout. Coaches contacted participants weekly to monitor their progress, and participants wore heart rate monitors during each session. Exercises in the control group were designed to promote flexibility and improve core strength. In the aerobic exercise group, participants had a choice of exercises such as walking on a treadmill, cycling on a stationary bike, or using an elliptical machine, and they gradually increased their exercise intensity to 75% of maximum heart rate by week 5. A total of 94 participants – 50 in the control group and 44 in the aerobic exercise group – completed the 6-month trial.

Executive function, but not other cognitive measures, improved significantly in the aerobic exercise group. The effect on executive function was greater in older participants. For example, at age 40 years, the executive function measure increased by 0.228 standard deviation units from baseline; at age 60, it increased by 0.596 standard deviation units.

In addition, cortical thickness increased significantly in the aerobic exercise group in the left caudal middle frontal cortex Brodmann area; this effect did not differ by age. Improvement on executive function in the aerobic exercise group was greater among participants without an APOE E4 allele, contrasting with the findings of prior studies.

“Since a difference of 0.5 standard deviations is equivalent to 20 years of age-related difference in performance on these tests, the people who exercised were testing as if they were about 10 years younger at age 40 and about 20 years younger at age 60,” Dr. Stern said in a press release. “Since thinking skills at the start of the study were poorer for participants who were older, our findings suggest that aerobic exercise is more likely to improve age-related declines in thinking skills rather than improve performance in those without a decline.”

Furthermore, aerobic exercise significantly increased aerobic capacity and significantly decreased body mass index, whereas stretching and toning did not.

“Participants in this trial scheduled their exercise sessions on their own and exercised by themselves,” the authors noted. “In addition, they were allowed to choose whatever aerobic exercise modality they preferred, so long as they reached target heart rates, enhancing the flexibility of the intervention.” Limitations of the study include its relatively small sample size and the large number of participants who dropped out of the study between consenting to participate and randomization.

The trial was funded by the National Institutes of Health. Dr. Stern reported receiving a grant from the California Walnut Commission and consulting with Eli Lilly, Axovant Sciences, Takeda, and AbbVie. A coauthor reported grant support from AposTherapy, LIH Medical, and the Everest Foundation.

[email protected]

SOURCE: Stern Y et al. Neurology. 2019 Jan 30. doi: 10.1212/WNL.0000000000007003.
 

Among adults with below-average fitness, aerobic exercise significantly improves executive function, according to a randomized clinical trial published in Neurology.

Chris Leary

“The effect of aerobic exercise on executive function was more pronounced as age increased, suggesting that it may mitigate age-related declines,” wrote Yaakov Stern, PhD, chief of cognitive neuroscience in the department of neurology at Columbia University, New York, and his research colleagues.

Research indicates that aerobic exercise provides cognitive benefits across the lifespan, but controlled exercise studies have been limited to elderly individuals, the researchers wrote. To examine the effects of aerobic exercise on cognitive function in younger, healthy adults, they conducted a randomized, parallel-group, observer-masked, community-based clinical trial. The investigators enrolled 132 cognitively normal people aged 20-67 years with aerobic capacity below the median. About 70% were women, and participants’ mean age was about 40 years.

“We hypothesized that aerobic exercise would have cognitive benefits, even in this younger age range, but that age might moderate the nature or degree of the benefit,” Dr. Stern and his colleagues wrote.

Participants were nonsmoking, habitual nonexercisers with below-average fitness by American Heart Association standards. The investigators used baseline aerobic capacity testing to establish safe exercise measures and heart rate targets.

The investigators randomly assigned participants to a group that performed aerobic exercise or to a control group that performed stretching and toning four times per week for 6 months. Outcome measures included domains of cognitive function (such as executive function, episodic memory, processing speed, language, and attention), everyday function, aerobic capacity, body mass index, and cortical thickness.

During a 2-week run-in period, participants went to their choice of five YMCA of New York City fitness centers three times per week. They had to attend at least five of these sessions to stay in the study. In both study arms, training sessions consisted of 10-15 minutes of warm-up and cooldown and 30-40 minutes of workout. Coaches contacted participants weekly to monitor their progress, and participants wore heart rate monitors during each session. Exercises in the control group were designed to promote flexibility and improve core strength. In the aerobic exercise group, participants had a choice of exercises such as walking on a treadmill, cycling on a stationary bike, or using an elliptical machine, and they gradually increased their exercise intensity to 75% of maximum heart rate by week 5. A total of 94 participants – 50 in the control group and 44 in the aerobic exercise group – completed the 6-month trial.

Executive function, but not other cognitive measures, improved significantly in the aerobic exercise group. The effect on executive function was greater in older participants. For example, at age 40 years, the executive function measure increased by 0.228 standard deviation units from baseline; at age 60, it increased by 0.596 standard deviation units.

In addition, cortical thickness increased significantly in the aerobic exercise group in the left caudal middle frontal cortex Brodmann area; this effect did not differ by age. Improvement on executive function in the aerobic exercise group was greater among participants without an APOE E4 allele, contrasting with the findings of prior studies.

“Since a difference of 0.5 standard deviations is equivalent to 20 years of age-related difference in performance on these tests, the people who exercised were testing as if they were about 10 years younger at age 40 and about 20 years younger at age 60,” Dr. Stern said in a press release. “Since thinking skills at the start of the study were poorer for participants who were older, our findings suggest that aerobic exercise is more likely to improve age-related declines in thinking skills rather than improve performance in those without a decline.”

Furthermore, aerobic exercise significantly increased aerobic capacity and significantly decreased body mass index, whereas stretching and toning did not.

“Participants in this trial scheduled their exercise sessions on their own and exercised by themselves,” the authors noted. “In addition, they were allowed to choose whatever aerobic exercise modality they preferred, so long as they reached target heart rates, enhancing the flexibility of the intervention.” Limitations of the study include its relatively small sample size and the large number of participants who dropped out of the study between consenting to participate and randomization.

The trial was funded by the National Institutes of Health. Dr. Stern reported receiving a grant from the California Walnut Commission and consulting with Eli Lilly, Axovant Sciences, Takeda, and AbbVie. A coauthor reported grant support from AposTherapy, LIH Medical, and the Everest Foundation.

[email protected]

SOURCE: Stern Y et al. Neurology. 2019 Jan 30. doi: 10.1212/WNL.0000000000007003.
 

Among adults with below-average fitness, aerobic exercise significantly improves executive function, according to a randomized clinical trial published in Neurology.

Chris Leary

“The effect of aerobic exercise on executive function was more pronounced as age increased, suggesting that it may mitigate age-related declines,” wrote Yaakov Stern, PhD, chief of cognitive neuroscience in the department of neurology at Columbia University, New York, and his research colleagues.

Research indicates that aerobic exercise provides cognitive benefits across the lifespan, but controlled exercise studies have been limited to elderly individuals, the researchers wrote. To examine the effects of aerobic exercise on cognitive function in younger, healthy adults, they conducted a randomized, parallel-group, observer-masked, community-based clinical trial. The investigators enrolled 132 cognitively normal people aged 20-67 years with aerobic capacity below the median. About 70% were women, and participants’ mean age was about 40 years.

“We hypothesized that aerobic exercise would have cognitive benefits, even in this younger age range, but that age might moderate the nature or degree of the benefit,” Dr. Stern and his colleagues wrote.

Participants were nonsmoking, habitual nonexercisers with below-average fitness by American Heart Association standards. The investigators used baseline aerobic capacity testing to establish safe exercise measures and heart rate targets.

The investigators randomly assigned participants to a group that performed aerobic exercise or to a control group that performed stretching and toning four times per week for 6 months. Outcome measures included domains of cognitive function (such as executive function, episodic memory, processing speed, language, and attention), everyday function, aerobic capacity, body mass index, and cortical thickness.

During a 2-week run-in period, participants went to their choice of five YMCA of New York City fitness centers three times per week. They had to attend at least five of these sessions to stay in the study. In both study arms, training sessions consisted of 10-15 minutes of warm-up and cooldown and 30-40 minutes of workout. Coaches contacted participants weekly to monitor their progress, and participants wore heart rate monitors during each session. Exercises in the control group were designed to promote flexibility and improve core strength. In the aerobic exercise group, participants had a choice of exercises such as walking on a treadmill, cycling on a stationary bike, or using an elliptical machine, and they gradually increased their exercise intensity to 75% of maximum heart rate by week 5. A total of 94 participants – 50 in the control group and 44 in the aerobic exercise group – completed the 6-month trial.

Executive function, but not other cognitive measures, improved significantly in the aerobic exercise group. The effect on executive function was greater in older participants. For example, at age 40 years, the executive function measure increased by 0.228 standard deviation units from baseline; at age 60, it increased by 0.596 standard deviation units.

In addition, cortical thickness increased significantly in the aerobic exercise group in the left caudal middle frontal cortex Brodmann area; this effect did not differ by age. Improvement on executive function in the aerobic exercise group was greater among participants without an APOE E4 allele, contrasting with the findings of prior studies.

“Since a difference of 0.5 standard deviations is equivalent to 20 years of age-related difference in performance on these tests, the people who exercised were testing as if they were about 10 years younger at age 40 and about 20 years younger at age 60,” Dr. Stern said in a press release. “Since thinking skills at the start of the study were poorer for participants who were older, our findings suggest that aerobic exercise is more likely to improve age-related declines in thinking skills rather than improve performance in those without a decline.”

Furthermore, aerobic exercise significantly increased aerobic capacity and significantly decreased body mass index, whereas stretching and toning did not.

“Participants in this trial scheduled their exercise sessions on their own and exercised by themselves,” the authors noted. “In addition, they were allowed to choose whatever aerobic exercise modality they preferred, so long as they reached target heart rates, enhancing the flexibility of the intervention.” Limitations of the study include its relatively small sample size and the large number of participants who dropped out of the study between consenting to participate and randomization.

The trial was funded by the National Institutes of Health. Dr. Stern reported receiving a grant from the California Walnut Commission and consulting with Eli Lilly, Axovant Sciences, Takeda, and AbbVie. A coauthor reported grant support from AposTherapy, LIH Medical, and the Everest Foundation.

[email protected]

SOURCE: Stern Y et al. Neurology. 2019 Jan 30. doi: 10.1212/WNL.0000000000007003.
 

After a disappointing interim analysis, Roche and its collaborator AC Immune are halting two phase 3 trials of the antiamyloid antibody crenezumab.

CREAD 1 and CREAD 2 enrolled patients with prodromal-to-mild sporadic Alzheimer’s disease. The preplanned interim safety and efficacy analysis determined that neither study was likely to meet the primary endpoint of change from baseline on the Clinical Dementia Rating-sum of boxes score.

There were no unexpected safety signals associated with the drug, despite a quadrupling of the phase 3 dose from that used in phase 2. The company in its press release said that it will continue to conduct the Autosomal Dominant Alzheimer’s Disease (ADAD) trial as part of the Alzheimer’s Prevention Initiative (API). ADAD is a large South American trial of crenezumab in Colombian families with familial Alzheimer’s caused by mutations in the presenilin-1 gene (PSEN1).

Roche did not release any data but said the trial results will be discussed at an upcoming scientific meeting.

“While the results with crenezumab are disappointing, they meaningfully contribute to our understanding of Alzheimer’s disease,” Sandra Horning, MD, Roche’s chief medical officer and executive vice president for global development, said in an interview. “We gratefully acknowledge the participants in the CREAD trials and the efforts of everyone involved in this important program.”

The decision was not a surprise to researchers who have followed the antibody’s development. It advanced into phase 3 with lackluster phase 2 cognitive, imaging, and biomarker data. Its selection as the therapeutic agent for the ADAD trial was a key driver in its continued development, securing Roche $100 million in federal funds to help launch ADAD, the first-ever Alzheimer’s primary prevention study.

Despite its failure in sporadic Alzheimer’s, there is still some hope that crenezumab might benefit people with the PSEN1 mutation, said Richard Caselli, MD, professor of neurology at the Mayo Clinic Arizona in Scottsdale and associate director and clinical core director of the Arizona Alzheimer’s Disease Center.

“The Colombian trial is aimed at dominantly-inherited AD due to a PSEN1 mutation, so it is different enough to imagine it still might make a difference in patients in whom amyloid metabolism is actually defective due to functionally altered amyloid precursor protein or gamma secretase,” he said in an interview. “Possibly some might argue that many of the patients in the crenezumab trial likely had additional pathologies so that even if the AD component responded, the overall clinical picture might not reflect it due to the other components. That would be interesting if proven and could even argue against equating young-onset with late-onset AD, at least for clinical purposes, as is currently envisioned.”

Michael Wolfe, PhD, had a different take on the matter.

“Although amyloid-beta [Abeta] production is not necessarily altered in sporadic AD, there is essentially the same pathology, presentation, and progression with familial and sporadic AD, suggesting a common molecular mechanism,” said Dr. Wolfe, who is the Mathias P. Mertes Professor of Medicinal Chemistry at the University of Kansas, Lawrence. “It’s hard to say Abeta is the pathogenic species in familial but not sporadic AD.

The antibodies that have been failing for 5 years now were designed in the early 2000s, Dr. Kupiec pointed out, when knowledge of the various amyloid species was still immature. Newer candidates can target specific conformations of the protein – monomers and oligomers – before they aggregate into insoluble sheets. “Solanezumab was the first of these, paving the way for this new generation of antibodies,” Dr. Kupiec said.

Because they target soluble Abeta, not amyloid plaques, these domain-specific antibodies are less likely to elicit ARIA (amyloid-related imaging abnormalities), the inflammatory reaction that’s been associated with plaque dissolution in other antibody trials. ARIA has been a dose-limiting step for antiamyloid antibodies – one that conformationally targeted antibodies could avoid, Dr. Kupiec said.

“There may be some limited success with the these, and there may be enough of a treatment effect to secure approval,” he said. “The question is: Can we generate a higher effect size with an antibody that is more selective to the toxic forms of Abeta?”

PMN310 is ProMIS’ attempt to thread this needle. In preclinical studies, the antibody did not bind to amyloid monomers, plaques, or vascular Abeta aggregates. The company expects to take this antibody into phase 1 trials later this year.

“If we have a molecule that doesn’t bind to monomers or to plaques, but only to the toxic oligomer, then that is an something well worth testing in the clinic,” he said.

Dr. Caselli and Dr. Wolfe have no financial disclosures.

[email protected]

After a disappointing interim analysis, Roche and its collaborator AC Immune are halting two phase 3 trials of the antiamyloid antibody crenezumab.

CREAD 1 and CREAD 2 enrolled patients with prodromal-to-mild sporadic Alzheimer’s disease. The preplanned interim safety and efficacy analysis determined that neither study was likely to meet the primary endpoint of change from baseline on the Clinical Dementia Rating-sum of boxes score.

There were no unexpected safety signals associated with the drug, despite a quadrupling of the phase 3 dose from that used in phase 2. The company in its press release said that it will continue to conduct the Autosomal Dominant Alzheimer’s Disease (ADAD) trial as part of the Alzheimer’s Prevention Initiative (API). ADAD is a large South American trial of crenezumab in Colombian families with familial Alzheimer’s caused by mutations in the presenilin-1 gene (PSEN1).

Roche did not release any data but said the trial results will be discussed at an upcoming scientific meeting.

“While the results with crenezumab are disappointing, they meaningfully contribute to our understanding of Alzheimer’s disease,” Sandra Horning, MD, Roche’s chief medical officer and executive vice president for global development, said in an interview. “We gratefully acknowledge the participants in the CREAD trials and the efforts of everyone involved in this important program.”

The decision was not a surprise to researchers who have followed the antibody’s development. It advanced into phase 3 with lackluster phase 2 cognitive, imaging, and biomarker data. Its selection as the therapeutic agent for the ADAD trial was a key driver in its continued development, securing Roche $100 million in federal funds to help launch ADAD, the first-ever Alzheimer’s primary prevention study.

Despite its failure in sporadic Alzheimer’s, there is still some hope that crenezumab might benefit people with the PSEN1 mutation, said Richard Caselli, MD, professor of neurology at the Mayo Clinic Arizona in Scottsdale and associate director and clinical core director of the Arizona Alzheimer’s Disease Center.

“The Colombian trial is aimed at dominantly-inherited AD due to a PSEN1 mutation, so it is different enough to imagine it still might make a difference in patients in whom amyloid metabolism is actually defective due to functionally altered amyloid precursor protein or gamma secretase,” he said in an interview. “Possibly some might argue that many of the patients in the crenezumab trial likely had additional pathologies so that even if the AD component responded, the overall clinical picture might not reflect it due to the other components. That would be interesting if proven and could even argue against equating young-onset with late-onset AD, at least for clinical purposes, as is currently envisioned.”

Michael Wolfe, PhD, had a different take on the matter.

“Although amyloid-beta [Abeta] production is not necessarily altered in sporadic AD, there is essentially the same pathology, presentation, and progression with familial and sporadic AD, suggesting a common molecular mechanism,” said Dr. Wolfe, who is the Mathias P. Mertes Professor of Medicinal Chemistry at the University of Kansas, Lawrence. “It’s hard to say Abeta is the pathogenic species in familial but not sporadic AD.

The antibodies that have been failing for 5 years now were designed in the early 2000s, Dr. Kupiec pointed out, when knowledge of the various amyloid species was still immature. Newer candidates can target specific conformations of the protein – monomers and oligomers – before they aggregate into insoluble sheets. “Solanezumab was the first of these, paving the way for this new generation of antibodies,” Dr. Kupiec said.

Because they target soluble Abeta, not amyloid plaques, these domain-specific antibodies are less likely to elicit ARIA (amyloid-related imaging abnormalities), the inflammatory reaction that’s been associated with plaque dissolution in other antibody trials. ARIA has been a dose-limiting step for antiamyloid antibodies – one that conformationally targeted antibodies could avoid, Dr. Kupiec said.

“There may be some limited success with the these, and there may be enough of a treatment effect to secure approval,” he said. “The question is: Can we generate a higher effect size with an antibody that is more selective to the toxic forms of Abeta?”

PMN310 is ProMIS’ attempt to thread this needle. In preclinical studies, the antibody did not bind to amyloid monomers, plaques, or vascular Abeta aggregates. The company expects to take this antibody into phase 1 trials later this year.

“If we have a molecule that doesn’t bind to monomers or to plaques, but only to the toxic oligomer, then that is an something well worth testing in the clinic,” he said.

Dr. Caselli and Dr. Wolfe have no financial disclosures.

[email protected]

After a disappointing interim analysis, Roche and its collaborator AC Immune are halting two phase 3 trials of the antiamyloid antibody crenezumab.

CREAD 1 and CREAD 2 enrolled patients with prodromal-to-mild sporadic Alzheimer’s disease. The preplanned interim safety and efficacy analysis determined that neither study was likely to meet the primary endpoint of change from baseline on the Clinical Dementia Rating-sum of boxes score.

There were no unexpected safety signals associated with the drug, despite a quadrupling of the phase 3 dose from that used in phase 2. The company in its press release said that it will continue to conduct the Autosomal Dominant Alzheimer’s Disease (ADAD) trial as part of the Alzheimer’s Prevention Initiative (API). ADAD is a large South American trial of crenezumab in Colombian families with familial Alzheimer’s caused by mutations in the presenilin-1 gene (PSEN1).

Roche did not release any data but said the trial results will be discussed at an upcoming scientific meeting.

“While the results with crenezumab are disappointing, they meaningfully contribute to our understanding of Alzheimer’s disease,” Sandra Horning, MD, Roche’s chief medical officer and executive vice president for global development, said in an interview. “We gratefully acknowledge the participants in the CREAD trials and the efforts of everyone involved in this important program.”

The decision was not a surprise to researchers who have followed the antibody’s development. It advanced into phase 3 with lackluster phase 2 cognitive, imaging, and biomarker data. Its selection as the therapeutic agent for the ADAD trial was a key driver in its continued development, securing Roche $100 million in federal funds to help launch ADAD, the first-ever Alzheimer’s primary prevention study.

Despite its failure in sporadic Alzheimer’s, there is still some hope that crenezumab might benefit people with the PSEN1 mutation, said Richard Caselli, MD, professor of neurology at the Mayo Clinic Arizona in Scottsdale and associate director and clinical core director of the Arizona Alzheimer’s Disease Center.

“The Colombian trial is aimed at dominantly-inherited AD due to a PSEN1 mutation, so it is different enough to imagine it still might make a difference in patients in whom amyloid metabolism is actually defective due to functionally altered amyloid precursor protein or gamma secretase,” he said in an interview. “Possibly some might argue that many of the patients in the crenezumab trial likely had additional pathologies so that even if the AD component responded, the overall clinical picture might not reflect it due to the other components. That would be interesting if proven and could even argue against equating young-onset with late-onset AD, at least for clinical purposes, as is currently envisioned.”

Michael Wolfe, PhD, had a different take on the matter.

“Although amyloid-beta [Abeta] production is not necessarily altered in sporadic AD, there is essentially the same pathology, presentation, and progression with familial and sporadic AD, suggesting a common molecular mechanism,” said Dr. Wolfe, who is the Mathias P. Mertes Professor of Medicinal Chemistry at the University of Kansas, Lawrence. “It’s hard to say Abeta is the pathogenic species in familial but not sporadic AD.

The antibodies that have been failing for 5 years now were designed in the early 2000s, Dr. Kupiec pointed out, when knowledge of the various amyloid species was still immature. Newer candidates can target specific conformations of the protein – monomers and oligomers – before they aggregate into insoluble sheets. “Solanezumab was the first of these, paving the way for this new generation of antibodies,” Dr. Kupiec said.

Because they target soluble Abeta, not amyloid plaques, these domain-specific antibodies are less likely to elicit ARIA (amyloid-related imaging abnormalities), the inflammatory reaction that’s been associated with plaque dissolution in other antibody trials. ARIA has been a dose-limiting step for antiamyloid antibodies – one that conformationally targeted antibodies could avoid, Dr. Kupiec said.

“There may be some limited success with the these, and there may be enough of a treatment effect to secure approval,” he said. “The question is: Can we generate a higher effect size with an antibody that is more selective to the toxic forms of Abeta?”

PMN310 is ProMIS’ attempt to thread this needle. In preclinical studies, the antibody did not bind to amyloid monomers, plaques, or vascular Abeta aggregates. The company expects to take this antibody into phase 1 trials later this year.

“If we have a molecule that doesn’t bind to monomers or to plaques, but only to the toxic oligomer, then that is an something well worth testing in the clinic,” he said.

Dr. Caselli and Dr. Wolfe have no financial disclosures.

[email protected]

A new iteration of the SPRINT MIND hypertension trial will seek to prove conclusively the original study’s tantalizing suggestion: that intensive blood pressure control decreases the risk of developing mild cognitive impairment (MCI) and, eventually, dementia.

SPRINT MIND 2.0 will re-recruit SPRINT MIND subjects and enable another follow-up cognitive assessment and other clinical tests as they remain on their standard of care blood pressure regimen. It is largely funded by an $800,000 grant from the Alzheimer’s Association.

Initially released last July at the Alzheimer’s Association International Conference, the results of the SPRINT MIND have now appeared online in JAMA. Although it failed to meet its primary endpoint of reducing dementia incidence, the study did score on two secondary endpoints. Patients who reduced their systolic blood pressure to less than 120 mm Hg were 19% less likely to develop MCI and 17% less likely to be diagnosed with all-cause dementia than were those who achieved a hypertension target of less than 140 mm Hg.

The secondary results, and positive movement in the primary results, sparked excitement in the dementia research community last summer. They have suggested that the median 5-year follow-up just wasn’t long enough to show any significant effects on dementia, which can take years to fully manifest. Adding 2 more years with SPRINT MIND 2.0 should be long enough to discern those benefits, if indeed they exist.

“SPRINT MIND 2.0 and the work leading up to it offers genuine, concrete hope,” Maria C. Carrillo, PhD, chief science officer for the Alzheimer’s Association, said in a press statement. “MCI is a known risk factor for dementia, and everyone who experiences dementia passes through MCI. When you prevent new cases of MCI, you are preventing new cases of dementia. The Alzheimer’s Association finds these data to be compelling and is committed to getting clarity and certainty on the dementia outcome by following participants for a longer period of time.”

The study strengthens the new and energetic push to find ways to prevent dementia, which has proven itself intractable in every drug study to date.

“This study is in line with where the field of dementia research is going: preventing memory loss earlier,” said Laurie Ryan, PhD, chief of the dementias of aging branch in the National Institute on Aging. “Much like we have research-based interventions for heart health and cancer prevention, we hope to have guidance based on this and subsequent studies that will more definitively show how to slow or even stop dementia well before symptoms appear.”

NIA director Richard J. Hodes, MD, agreed.

“Dementia continues to be a large public health challenge, and based on the primary results of this study, we still have yet to find an intervention strategy proven to reduce the risk of dementia,” he said in a press statement. “Nevertheless, the secondary results showing that intensive lowering of blood pressure may reduce risk for MCI, a known risk factor for dementia, gives us additional avenues to explore on the path to prevention.”

SPRINT MIND was a substudy of the Systolic Blood Pressure Intervention Trial (SPRINT). It compared two strategies for managing hypertension in older adults. The intensive strategy had a target of less than 120 mm Hg, while standard care had a target of less than 140 mm Hg. SPRINT showed that more intensive blood pressure control produced a 25% reduction in the composite primary composite endpoint of cardiovascular events, stroke, and cardiovascular death. The intensive arm was so successful that SPRINT helped inform the 2017 high blood pressure clinical guidelines from the American Heart Association and American College of Cardiology.

Michelle Sullivan/MDedge News

The SPRINT MIND substudy, headed by Jeff D. Williamson, MD, of Wake Forest University, Winston-Salem, NC, asked whether intensive management had any effect on probable all-cause dementia or MCI, as well as imaging evidence of changes in white matter lesions and brain volume. It followed patients for up to 7 years and comprised 9,361 SPRINT subjects at least 50 years old (mean, 68 years) with at least one cardiovascular risk factor. Nearly a third (30%) were black, and 10% Hispanic. The primary outcome was incident probable dementia. Secondary outcomes were MCI and a composite of MCI and/or probable dementia. About a third had a SBP of 132 mm Hg or less, another third had a systolic pressure of 132-145 mm Hg, and the remainder had a systolic pressure greater than 145 mm Hg.

Physicians could use their choice of antihypertensive treatments. The study protocol encouraged, but did not mandate, thiazide-type diuretics as a first-line agent, followed by loop diuretics and beta-adrenergic blockers. Chlorthalidone was encouraged as the primary thiazide-type diuretic, and amlodipine as the preferred calcium-channel blocker.

The interventions did successfully control blood pressure, with a significant difference between the treatment groups. The mean SBP was 121.6 mm Hg in the intensive therapy group and 134.8 mm Hg in the standard group – a statistically significant difference of 13.3 mm Hg.

Dementia developed in 149 in the aggressive control group and 176 in the standard group – a nonsignificant difference of 17% (hazard ratio, 0.83). MCI developed in 287 in the intensive group and 353 in the standard treatment group. This amounted to a statistically significant 19% reduction. There was also a significant 15% reduction in the composite outcome of MCI or probable dementia in favor of intensive treatment.

As evidenced by the Alzheimer’s Association grant, dementia researchers chose to focus on SPRINT MIND’s positive secondary endpoints. At the AAIC meeting, Dr. Williamson even suggested that antihypertensive medications could be seen as disease-modifying agents for cognitive decline. Data support his claim: No dementia intervention yet tested has approached this level of success.

“I think we can say this is the first disease-modifying strategy to reduce the risk of MCI,” Dr. Williamson said during a press briefing. And although the primary endpoint – the 17% relative risk reduction for probable all-cause dementia – didn’t meet statistical significance, “It’s comforting to see that the benefit went in the same direction and was of the same magnitude..”

[email protected]

SOURCE: Williamson JD et al. JAMA 2019 Jan 28. doi:10.1001/jama.2018.21442.

A new iteration of the SPRINT MIND hypertension trial will seek to prove conclusively the original study’s tantalizing suggestion: that intensive blood pressure control decreases the risk of developing mild cognitive impairment (MCI) and, eventually, dementia.

SPRINT MIND 2.0 will re-recruit SPRINT MIND subjects and enable another follow-up cognitive assessment and other clinical tests as they remain on their standard of care blood pressure regimen. It is largely funded by an $800,000 grant from the Alzheimer’s Association.

Initially released last July at the Alzheimer’s Association International Conference, the results of the SPRINT MIND have now appeared online in JAMA. Although it failed to meet its primary endpoint of reducing dementia incidence, the study did score on two secondary endpoints. Patients who reduced their systolic blood pressure to less than 120 mm Hg were 19% less likely to develop MCI and 17% less likely to be diagnosed with all-cause dementia than were those who achieved a hypertension target of less than 140 mm Hg.

The secondary results, and positive movement in the primary results, sparked excitement in the dementia research community last summer. They have suggested that the median 5-year follow-up just wasn’t long enough to show any significant effects on dementia, which can take years to fully manifest. Adding 2 more years with SPRINT MIND 2.0 should be long enough to discern those benefits, if indeed they exist.

“SPRINT MIND 2.0 and the work leading up to it offers genuine, concrete hope,” Maria C. Carrillo, PhD, chief science officer for the Alzheimer’s Association, said in a press statement. “MCI is a known risk factor for dementia, and everyone who experiences dementia passes through MCI. When you prevent new cases of MCI, you are preventing new cases of dementia. The Alzheimer’s Association finds these data to be compelling and is committed to getting clarity and certainty on the dementia outcome by following participants for a longer period of time.”

The study strengthens the new and energetic push to find ways to prevent dementia, which has proven itself intractable in every drug study to date.

“This study is in line with where the field of dementia research is going: preventing memory loss earlier,” said Laurie Ryan, PhD, chief of the dementias of aging branch in the National Institute on Aging. “Much like we have research-based interventions for heart health and cancer prevention, we hope to have guidance based on this and subsequent studies that will more definitively show how to slow or even stop dementia well before symptoms appear.”

NIA director Richard J. Hodes, MD, agreed.

“Dementia continues to be a large public health challenge, and based on the primary results of this study, we still have yet to find an intervention strategy proven to reduce the risk of dementia,” he said in a press statement. “Nevertheless, the secondary results showing that intensive lowering of blood pressure may reduce risk for MCI, a known risk factor for dementia, gives us additional avenues to explore on the path to prevention.”

SPRINT MIND was a substudy of the Systolic Blood Pressure Intervention Trial (SPRINT). It compared two strategies for managing hypertension in older adults. The intensive strategy had a target of less than 120 mm Hg, while standard care had a target of less than 140 mm Hg. SPRINT showed that more intensive blood pressure control produced a 25% reduction in the composite primary composite endpoint of cardiovascular events, stroke, and cardiovascular death. The intensive arm was so successful that SPRINT helped inform the 2017 high blood pressure clinical guidelines from the American Heart Association and American College of Cardiology.

Michelle Sullivan/MDedge News

The SPRINT MIND substudy, headed by Jeff D. Williamson, MD, of Wake Forest University, Winston-Salem, NC, asked whether intensive management had any effect on probable all-cause dementia or MCI, as well as imaging evidence of changes in white matter lesions and brain volume. It followed patients for up to 7 years and comprised 9,361 SPRINT subjects at least 50 years old (mean, 68 years) with at least one cardiovascular risk factor. Nearly a third (30%) were black, and 10% Hispanic. The primary outcome was incident probable dementia. Secondary outcomes were MCI and a composite of MCI and/or probable dementia. About a third had a SBP of 132 mm Hg or less, another third had a systolic pressure of 132-145 mm Hg, and the remainder had a systolic pressure greater than 145 mm Hg.

Physicians could use their choice of antihypertensive treatments. The study protocol encouraged, but did not mandate, thiazide-type diuretics as a first-line agent, followed by loop diuretics and beta-adrenergic blockers. Chlorthalidone was encouraged as the primary thiazide-type diuretic, and amlodipine as the preferred calcium-channel blocker.

The interventions did successfully control blood pressure, with a significant difference between the treatment groups. The mean SBP was 121.6 mm Hg in the intensive therapy group and 134.8 mm Hg in the standard group – a statistically significant difference of 13.3 mm Hg.

Dementia developed in 149 in the aggressive control group and 176 in the standard group – a nonsignificant difference of 17% (hazard ratio, 0.83). MCI developed in 287 in the intensive group and 353 in the standard treatment group. This amounted to a statistically significant 19% reduction. There was also a significant 15% reduction in the composite outcome of MCI or probable dementia in favor of intensive treatment.

As evidenced by the Alzheimer’s Association grant, dementia researchers chose to focus on SPRINT MIND’s positive secondary endpoints. At the AAIC meeting, Dr. Williamson even suggested that antihypertensive medications could be seen as disease-modifying agents for cognitive decline. Data support his claim: No dementia intervention yet tested has approached this level of success.

“I think we can say this is the first disease-modifying strategy to reduce the risk of MCI,” Dr. Williamson said during a press briefing. And although the primary endpoint – the 17% relative risk reduction for probable all-cause dementia – didn’t meet statistical significance, “It’s comforting to see that the benefit went in the same direction and was of the same magnitude..”

[email protected]

SOURCE: Williamson JD et al. JAMA 2019 Jan 28. doi:10.1001/jama.2018.21442.

A new iteration of the SPRINT MIND hypertension trial will seek to prove conclusively the original study’s tantalizing suggestion: that intensive blood pressure control decreases the risk of developing mild cognitive impairment (MCI) and, eventually, dementia.

SPRINT MIND 2.0 will re-recruit SPRINT MIND subjects and enable another follow-up cognitive assessment and other clinical tests as they remain on their standard of care blood pressure regimen. It is largely funded by an $800,000 grant from the Alzheimer’s Association.

Initially released last July at the Alzheimer’s Association International Conference, the results of the SPRINT MIND have now appeared online in JAMA. Although it failed to meet its primary endpoint of reducing dementia incidence, the study did score on two secondary endpoints. Patients who reduced their systolic blood pressure to less than 120 mm Hg were 19% less likely to develop MCI and 17% less likely to be diagnosed with all-cause dementia than were those who achieved a hypertension target of less than 140 mm Hg.

The secondary results, and positive movement in the primary results, sparked excitement in the dementia research community last summer. They have suggested that the median 5-year follow-up just wasn’t long enough to show any significant effects on dementia, which can take years to fully manifest. Adding 2 more years with SPRINT MIND 2.0 should be long enough to discern those benefits, if indeed they exist.

“SPRINT MIND 2.0 and the work leading up to it offers genuine, concrete hope,” Maria C. Carrillo, PhD, chief science officer for the Alzheimer’s Association, said in a press statement. “MCI is a known risk factor for dementia, and everyone who experiences dementia passes through MCI. When you prevent new cases of MCI, you are preventing new cases of dementia. The Alzheimer’s Association finds these data to be compelling and is committed to getting clarity and certainty on the dementia outcome by following participants for a longer period of time.”

The study strengthens the new and energetic push to find ways to prevent dementia, which has proven itself intractable in every drug study to date.

“This study is in line with where the field of dementia research is going: preventing memory loss earlier,” said Laurie Ryan, PhD, chief of the dementias of aging branch in the National Institute on Aging. “Much like we have research-based interventions for heart health and cancer prevention, we hope to have guidance based on this and subsequent studies that will more definitively show how to slow or even stop dementia well before symptoms appear.”

NIA director Richard J. Hodes, MD, agreed.

“Dementia continues to be a large public health challenge, and based on the primary results of this study, we still have yet to find an intervention strategy proven to reduce the risk of dementia,” he said in a press statement. “Nevertheless, the secondary results showing that intensive lowering of blood pressure may reduce risk for MCI, a known risk factor for dementia, gives us additional avenues to explore on the path to prevention.”

SPRINT MIND was a substudy of the Systolic Blood Pressure Intervention Trial (SPRINT). It compared two strategies for managing hypertension in older adults. The intensive strategy had a target of less than 120 mm Hg, while standard care had a target of less than 140 mm Hg. SPRINT showed that more intensive blood pressure control produced a 25% reduction in the composite primary composite endpoint of cardiovascular events, stroke, and cardiovascular death. The intensive arm was so successful that SPRINT helped inform the 2017 high blood pressure clinical guidelines from the American Heart Association and American College of Cardiology.

Michelle Sullivan/MDedge News

The SPRINT MIND substudy, headed by Jeff D. Williamson, MD, of Wake Forest University, Winston-Salem, NC, asked whether intensive management had any effect on probable all-cause dementia or MCI, as well as imaging evidence of changes in white matter lesions and brain volume. It followed patients for up to 7 years and comprised 9,361 SPRINT subjects at least 50 years old (mean, 68 years) with at least one cardiovascular risk factor. Nearly a third (30%) were black, and 10% Hispanic. The primary outcome was incident probable dementia. Secondary outcomes were MCI and a composite of MCI and/or probable dementia. About a third had a SBP of 132 mm Hg or less, another third had a systolic pressure of 132-145 mm Hg, and the remainder had a systolic pressure greater than 145 mm Hg.

Physicians could use their choice of antihypertensive treatments. The study protocol encouraged, but did not mandate, thiazide-type diuretics as a first-line agent, followed by loop diuretics and beta-adrenergic blockers. Chlorthalidone was encouraged as the primary thiazide-type diuretic, and amlodipine as the preferred calcium-channel blocker.

The interventions did successfully control blood pressure, with a significant difference between the treatment groups. The mean SBP was 121.6 mm Hg in the intensive therapy group and 134.8 mm Hg in the standard group – a statistically significant difference of 13.3 mm Hg.

Dementia developed in 149 in the aggressive control group and 176 in the standard group – a nonsignificant difference of 17% (hazard ratio, 0.83). MCI developed in 287 in the intensive group and 353 in the standard treatment group. This amounted to a statistically significant 19% reduction. There was also a significant 15% reduction in the composite outcome of MCI or probable dementia in favor of intensive treatment.

As evidenced by the Alzheimer’s Association grant, dementia researchers chose to focus on SPRINT MIND’s positive secondary endpoints. At the AAIC meeting, Dr. Williamson even suggested that antihypertensive medications could be seen as disease-modifying agents for cognitive decline. Data support his claim: No dementia intervention yet tested has approached this level of success.

“I think we can say this is the first disease-modifying strategy to reduce the risk of MCI,” Dr. Williamson said during a press briefing. And although the primary endpoint – the 17% relative risk reduction for probable all-cause dementia – didn’t meet statistical significance, “It’s comforting to see that the benefit went in the same direction and was of the same magnitude..”

[email protected]

SOURCE: Williamson JD et al. JAMA 2019 Jan 28. doi:10.1001/jama.2018.21442.

Among people of the same age, the degree of frailty influences the association between Alzheimer’s disease pathology and Alzheimer’s dementia, according to research published online ahead of print Jan. 17 in Lancet Neurology. Data suggest that frailty reduces the threshold for Alzheimer’s disease pathology to cause cognitive decline. Frailty also may contribute to other mechanisms that cause dementia, such as inflammation and immunosenescence, said the investigators.

“While more research is needed, given that frailty is potentially reversible, it is possible that helping people to maintain function and independence in later life could reduce both dementia risk and the severity of debilitating symptoms common in this disease,” said Professor Kenneth Rockwood, MD, of the Nova Scotia Health Authority and Dalhousie University in Halifax, N.S., in a press release.
 

More susceptible to dementia?

The presence of amyloid plaques and neurofibrillary tangles is not a sufficient condition for the clinical expression of dementia. Some patients with a high degree of Alzheimer’s disease pathology have no apparent cognitive decline. Other factors therefore may modify the relationship between pathology and dementia.

Most people who develop Alzheimer’s disease dementia are older than 65 years, and many of these patients are frail. Frailty is understood as a decreased physiologic reserve and an increased risk for adverse health outcomes. Dr. Rockwood and his colleagues hypothesized that frailty moderates the clinical expression of dementia in relation to Alzheimer’s disease pathology.

To test their hypothesis, the investigators performed a cross-sectional analysis of data from the Rush Memory and Aging Project, which collects clinical and pathologic data from adults older than 59 years without dementia at baseline who live in Illinois. Since 1997, participants have undergone annual clinical and neuropsychological evaluations, and the cohort has been followed for 21 years. For their analysis, Dr. Rockwood and his colleagues included participants without dementia or with Alzheimer’s dementia at their last clinical assessment. Eligible participants had died, and complete autopsy data were available for them.

The researchers measured Alzheimer’s disease pathology using a summary measure of neurofibrillary tangles and neuritic and diffuse plaques. Clinical diagnoses of Alzheimer’s dementia were based on clinician consensus. Dr. Rockwood and his colleagues retrospectively created a 41-item frailty index from variables (e.g., symptoms, signs, comorbidities, and function) that were obtained at each clinical evaluation.

Logistic regression and moderation modeling allowed the investigators to evaluate relationships between Alzheimer’s disease pathology, frailty, and Alzheimer’s dementia. Dr. Rockwood and hus colleagues adjusted all analyses for age, sex, and education.

In all, 456 participants were included in the analysis. The sample’s mean age at death was 89.7 years, and 69% of participants were women. At participants’ last clinical assessment, 242 (53%) had possible or probable Alzheimer’s dementia.

The sample’s mean frailty index was 0.42. The median frailty index was 0.41, a value similar to the threshold commonly used to distinguish between moderate and severe frailty. People with high frailty index scores (i.e., 0.41 or greater) were older, had lower Mini-Mental State Examination scores, were more likely to have a diagnosis of dementia, and had a higher Braak stage than those with moderate or low frailty index scores.
 

Significant interaction between frailty and Alzheimer’s disease

After the investigators adjusted for age, sex, and education, frailty (odds ratio, 1.76) and Alzheimer’s disease pathology (OR, 4.81) were independently associated with Alzheimer’s dementia. When the investigators added frailty to the model for the relationship between Alzheimer’s disease pathology and Alzheimer’s dementia, the model fit improved. They found a significant interaction between frailty and Alzheimer’s disease pathology (OR, 0.73). People with a low amount of frailty were better able to tolerate Alzheimer’s disease pathology, and people with higher amounts of frailty were more likely to have more Alzheimer’s disease pathology and clinical dementia.

One of the study’s limitations is that it is a secondary analysis, according to Dr. Rockwood and his colleagues. In addition, frailty was measured close to participants’ time of death, and the measurements may thus reflect terminal decline. Participant deaths resulting from causes other than those related to dementia might have confounded the results. Finally, the sample came entirely from people living in retirement homes in Illinois, which might have introduced bias. Future research should use a population-based sample, said the authors.

Frailty could be a basis for risk stratification and could inform the management and treatment of older adults, said Dr. Rockwood and his colleagues. The study results have “the potential to improve our understanding of disease expression, explain failures in pharmacologic treatment, and aid in the development of more appropriate therapeutic targets, approaches, and measurements of success,” they concluded.

The study had no source of funding. The authors reported receiving fees and grants from DGI Clinical, GlaxoSmithKline, Pfizer, and Sanofi. Authors also received support from governmental bodies such as the National Institutes of Health and the Canadian Institutes of Health Research.

[email protected]

SOURCE: Wallace LMK et al. Lancet Neurol. 2019;18:177-84.

Among people of the same age, the degree of frailty influences the association between Alzheimer’s disease pathology and Alzheimer’s dementia, according to research published online ahead of print Jan. 17 in Lancet Neurology. Data suggest that frailty reduces the threshold for Alzheimer’s disease pathology to cause cognitive decline. Frailty also may contribute to other mechanisms that cause dementia, such as inflammation and immunosenescence, said the investigators.

“While more research is needed, given that frailty is potentially reversible, it is possible that helping people to maintain function and independence in later life could reduce both dementia risk and the severity of debilitating symptoms common in this disease,” said Professor Kenneth Rockwood, MD, of the Nova Scotia Health Authority and Dalhousie University in Halifax, N.S., in a press release.
 

More susceptible to dementia?

The presence of amyloid plaques and neurofibrillary tangles is not a sufficient condition for the clinical expression of dementia. Some patients with a high degree of Alzheimer’s disease pathology have no apparent cognitive decline. Other factors therefore may modify the relationship between pathology and dementia.

Most people who develop Alzheimer’s disease dementia are older than 65 years, and many of these patients are frail. Frailty is understood as a decreased physiologic reserve and an increased risk for adverse health outcomes. Dr. Rockwood and his colleagues hypothesized that frailty moderates the clinical expression of dementia in relation to Alzheimer’s disease pathology.

To test their hypothesis, the investigators performed a cross-sectional analysis of data from the Rush Memory and Aging Project, which collects clinical and pathologic data from adults older than 59 years without dementia at baseline who live in Illinois. Since 1997, participants have undergone annual clinical and neuropsychological evaluations, and the cohort has been followed for 21 years. For their analysis, Dr. Rockwood and his colleagues included participants without dementia or with Alzheimer’s dementia at their last clinical assessment. Eligible participants had died, and complete autopsy data were available for them.

The researchers measured Alzheimer’s disease pathology using a summary measure of neurofibrillary tangles and neuritic and diffuse plaques. Clinical diagnoses of Alzheimer’s dementia were based on clinician consensus. Dr. Rockwood and his colleagues retrospectively created a 41-item frailty index from variables (e.g., symptoms, signs, comorbidities, and function) that were obtained at each clinical evaluation.

Logistic regression and moderation modeling allowed the investigators to evaluate relationships between Alzheimer’s disease pathology, frailty, and Alzheimer’s dementia. Dr. Rockwood and hus colleagues adjusted all analyses for age, sex, and education.

In all, 456 participants were included in the analysis. The sample’s mean age at death was 89.7 years, and 69% of participants were women. At participants’ last clinical assessment, 242 (53%) had possible or probable Alzheimer’s dementia.

The sample’s mean frailty index was 0.42. The median frailty index was 0.41, a value similar to the threshold commonly used to distinguish between moderate and severe frailty. People with high frailty index scores (i.e., 0.41 or greater) were older, had lower Mini-Mental State Examination scores, were more likely to have a diagnosis of dementia, and had a higher Braak stage than those with moderate or low frailty index scores.
 

Significant interaction between frailty and Alzheimer’s disease

After the investigators adjusted for age, sex, and education, frailty (odds ratio, 1.76) and Alzheimer’s disease pathology (OR, 4.81) were independently associated with Alzheimer’s dementia. When the investigators added frailty to the model for the relationship between Alzheimer’s disease pathology and Alzheimer’s dementia, the model fit improved. They found a significant interaction between frailty and Alzheimer’s disease pathology (OR, 0.73). People with a low amount of frailty were better able to tolerate Alzheimer’s disease pathology, and people with higher amounts of frailty were more likely to have more Alzheimer’s disease pathology and clinical dementia.

One of the study’s limitations is that it is a secondary analysis, according to Dr. Rockwood and his colleagues. In addition, frailty was measured close to participants’ time of death, and the measurements may thus reflect terminal decline. Participant deaths resulting from causes other than those related to dementia might have confounded the results. Finally, the sample came entirely from people living in retirement homes in Illinois, which might have introduced bias. Future research should use a population-based sample, said the authors.

Frailty could be a basis for risk stratification and could inform the management and treatment of older adults, said Dr. Rockwood and his colleagues. The study results have “the potential to improve our understanding of disease expression, explain failures in pharmacologic treatment, and aid in the development of more appropriate therapeutic targets, approaches, and measurements of success,” they concluded.

The study had no source of funding. The authors reported receiving fees and grants from DGI Clinical, GlaxoSmithKline, Pfizer, and Sanofi. Authors also received support from governmental bodies such as the National Institutes of Health and the Canadian Institutes of Health Research.

[email protected]

SOURCE: Wallace LMK et al. Lancet Neurol. 2019;18:177-84.

Among people of the same age, the degree of frailty influences the association between Alzheimer’s disease pathology and Alzheimer’s dementia, according to research published online ahead of print Jan. 17 in Lancet Neurology. Data suggest that frailty reduces the threshold for Alzheimer’s disease pathology to cause cognitive decline. Frailty also may contribute to other mechanisms that cause dementia, such as inflammation and immunosenescence, said the investigators.

“While more research is needed, given that frailty is potentially reversible, it is possible that helping people to maintain function and independence in later life could reduce both dementia risk and the severity of debilitating symptoms common in this disease,” said Professor Kenneth Rockwood, MD, of the Nova Scotia Health Authority and Dalhousie University in Halifax, N.S., in a press release.
 

More susceptible to dementia?

The presence of amyloid plaques and neurofibrillary tangles is not a sufficient condition for the clinical expression of dementia. Some patients with a high degree of Alzheimer’s disease pathology have no apparent cognitive decline. Other factors therefore may modify the relationship between pathology and dementia.

Most people who develop Alzheimer’s disease dementia are older than 65 years, and many of these patients are frail. Frailty is understood as a decreased physiologic reserve and an increased risk for adverse health outcomes. Dr. Rockwood and his colleagues hypothesized that frailty moderates the clinical expression of dementia in relation to Alzheimer’s disease pathology.

To test their hypothesis, the investigators performed a cross-sectional analysis of data from the Rush Memory and Aging Project, which collects clinical and pathologic data from adults older than 59 years without dementia at baseline who live in Illinois. Since 1997, participants have undergone annual clinical and neuropsychological evaluations, and the cohort has been followed for 21 years. For their analysis, Dr. Rockwood and his colleagues included participants without dementia or with Alzheimer’s dementia at their last clinical assessment. Eligible participants had died, and complete autopsy data were available for them.

The researchers measured Alzheimer’s disease pathology using a summary measure of neurofibrillary tangles and neuritic and diffuse plaques. Clinical diagnoses of Alzheimer’s dementia were based on clinician consensus. Dr. Rockwood and his colleagues retrospectively created a 41-item frailty index from variables (e.g., symptoms, signs, comorbidities, and function) that were obtained at each clinical evaluation.

Logistic regression and moderation modeling allowed the investigators to evaluate relationships between Alzheimer’s disease pathology, frailty, and Alzheimer’s dementia. Dr. Rockwood and hus colleagues adjusted all analyses for age, sex, and education.

In all, 456 participants were included in the analysis. The sample’s mean age at death was 89.7 years, and 69% of participants were women. At participants’ last clinical assessment, 242 (53%) had possible or probable Alzheimer’s dementia.

The sample’s mean frailty index was 0.42. The median frailty index was 0.41, a value similar to the threshold commonly used to distinguish between moderate and severe frailty. People with high frailty index scores (i.e., 0.41 or greater) were older, had lower Mini-Mental State Examination scores, were more likely to have a diagnosis of dementia, and had a higher Braak stage than those with moderate or low frailty index scores.
 

Significant interaction between frailty and Alzheimer’s disease

After the investigators adjusted for age, sex, and education, frailty (odds ratio, 1.76) and Alzheimer’s disease pathology (OR, 4.81) were independently associated with Alzheimer’s dementia. When the investigators added frailty to the model for the relationship between Alzheimer’s disease pathology and Alzheimer’s dementia, the model fit improved. They found a significant interaction between frailty and Alzheimer’s disease pathology (OR, 0.73). People with a low amount of frailty were better able to tolerate Alzheimer’s disease pathology, and people with higher amounts of frailty were more likely to have more Alzheimer’s disease pathology and clinical dementia.

One of the study’s limitations is that it is a secondary analysis, according to Dr. Rockwood and his colleagues. In addition, frailty was measured close to participants’ time of death, and the measurements may thus reflect terminal decline. Participant deaths resulting from causes other than those related to dementia might have confounded the results. Finally, the sample came entirely from people living in retirement homes in Illinois, which might have introduced bias. Future research should use a population-based sample, said the authors.

Frailty could be a basis for risk stratification and could inform the management and treatment of older adults, said Dr. Rockwood and his colleagues. The study results have “the potential to improve our understanding of disease expression, explain failures in pharmacologic treatment, and aid in the development of more appropriate therapeutic targets, approaches, and measurements of success,” they concluded.

The study had no source of funding. The authors reported receiving fees and grants from DGI Clinical, GlaxoSmithKline, Pfizer, and Sanofi. Authors also received support from governmental bodies such as the National Institutes of Health and the Canadian Institutes of Health Research.

[email protected]

SOURCE: Wallace LMK et al. Lancet Neurol. 2019;18:177-84.