Older adults with severe apathy, or lack of interest in usual activities, may have a greater chance of developing dementia than people with few symptoms of apathy, according to a study from the University of California – San Francisco – published in Neurology, the medical journal of the American Academy of Neurology.
“Apathy can be very distressing for family members, when people no longer want to get together with family or friends or donʼt seem interested in what they used to enjoy,” said study author Dr Meredith Bock of the University of California, San Francisco.
“More research is needed, but it is possible that these are signs that people may be at risk for Alzheimerʼs disease and could benefit from early interventions and efforts to reduce other risk factors.”
The study was published in the 14 October 2020 online issue of Neurology, and was reported in a release from the American Academy of Neurology – the world's largest association of neurologists and neuroscience professionals, with 36,000 members.
The study
The study involved 2,018 adults with an average age of 74. None had dementia.
At the start of the study, researchers measured apathy using a survey with questions such as: “In the past four weeks, how often have you been interested in leaving your home and going out?” and: “In the past 4 weeks, how often have you been interested in doing your usual activities?”
Participants were then divided into three groups: those with low, moderate and severe apathy.
After nine years, researchers determined who had dementia by looking at medication use, hospital records and results on cognitive tests.
By the end of the study, 381 participants, or almost 19%, developed dementia. In the low apathy group, 111 out of 768 people, or 14%, developed dementia, compared to 143 out of 742 people, or 19%, in the moderate apathy group. In the severe apathy group, 127 out of 508
people, or 25%, developed dementia.
After adjusting for age, education, cardiovascular risk factors and other factors that could affect dementia risk, they found that people with severe apathy were 80% more likely to
develop dementia than people with low apathy.
Greater apathy was also associated with worse cognitive score at the beginning of the study.
“While depression has been studied more extensively as a predictor of dementia, our study adds to the research showing that apathy also deserves attention as an independent predictor of the disease,” Bock said.
“In fact, we believe that apathy may be a very early sign of dementia and it can be evaluated with a brief questionnaire.”
A limitation of the study is that an algorithm was used to diagnose dementia, which may not be as sensitive as an in-depth evaluation by a doctor.
The study was supported by the National Institute on Aging.
Apathy and risk of probable incident dementia among community-dwelling older adults
Neurology, the journal of the American Academy of Neurology. Published on 14 October 2020
Authors
Meredith A Bock, Amber Bahorik, Willa D Brenowitz and Kristine Yaffe
University of California, San Francisco, and the San Francisco Veterans Affairs Medical Center
Abstract
The objective was to evaluate the association between baseline apathy and probable incident dementia in a population-based sample of community-dwelling older adults.
Methods
We studied 2,018 white and black community-dwelling older adults from the Health, Aging, and Body Composition (Health ABC) study.
We measured apathy at year 6 (our study baseline) with the modified Apathy Evaluation Scale and divided participants into tertiles based on low, moderate, or severe apathy symptoms. Incident dementia was ascertained over 9 years by dementia medication use, hospital records, or clinically relevant cognitive decline on global cognition.
We examined the association between apathy and probable incident dementia using a Cox proportional hazards model adjusting for demographics, cardiovascular risk factors, APOE-4 status, and depressed mood. We also evaluated the association between the apathy group and cognitive change (as measured by the Modified Mini Mental State Examination and Digit Symbol Substitution Test over 5 years) using linear mixed effects models.
Results
Over 9 years of follow-up, 381 participants developed probable dementia. Severe apathy was associated with an increased risk of dementia compared to low apathy (25% vs 14%) in unadjusted (HR 1.9, 95% CI 1.5–2.5) and adjusted models (HR 1.7, 95% CI 1.3–2.2). Greater apathy was associated with worse cognitive score at baseline, but not rate of change over time.
Conclusion
In a diverse cohort of community-dwelling adults, apathy was associated with increased risk of developing probable dementia. This study provides novel evidence for apathy as a prodrome of dementia.
[link url="https://www.aan.com/PressRoom/Home/PressRelease/3828"]AAN material: Could Loss of Interest Be Sign of Dementia Risk?[/link]
[link url="https://n.neurology.org/content/early/2020/10/14/WNL.0000000000010951"]Neurology abstract: Apathy and risk of probable incident dementia among community-dwelling older adults[/link]