Excessive daytime napping in older adults might be a signal for an increased future risk of Alzheimer’s dementia, and a diagnosis of Alzheimer’s dementia could hasten the increase in daytime napping with aging, according to a new study by researchers from Brigham and Women’s Hospital.
The findings have been published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association.
“Our results not only suggest that excessive daytime napping may signal an elevated risk of Alzheimer’s dementia, but they also show that faster yearly increase in daytime napping may be a sign of deteriorating or unfavored clinical progression of the disease,” said Peng Li, Ph.D., of the Medical Biodynamics Program in the Brigham’s Division of Sleep and Circadian Disorders.
Details of the Study
The study aimed to test two hypotheses:
(1) Participants nap longer and/or more frequently with aging and the changes are even faster with the progression of Alzheimer’s dementia; and (2) participants with excessive daytime napping are at an increased risk of developing Alzheimer’s dementia.
Over 1,000 individuals, averaging 81 years of age, wore Actical, a watch-like device, for up to 14 days to monitor their sleep patterns.
The device helped to identify sleep episodes based on wrist activity counts, and calculated nap duration and frequency.
The researchers found that longer and more frequent daytime naps were risk factors for developing Alzheimer’s dementia in cognitively normal older men and women, even when considering known risk factors such as age and nighttime sleep duration and fragmentation.
Also, yearly increases in napping duration and frequency were observed to accelerate as Alzheimer’s dementia progressed, particularly after its clinical manifestation.
The authors describe this relationship between daytime napping and cognition as a “vicious cycle.”
Implications and Recommendations
The study calls for closer attention to 24-hour sleep patterns, including daytime sleep, for health monitoring in older adults.
The researchers suggest that changes in sleep patterns could be significant in understanding the internal changes in the brain related to circadian clocks, cognitive decline, and the risk of dementia.
“Our hope is to draw more attention to daytime sleep patterns and the importance of patients noting if their sleep schedule is changing over time,” said co-senior author Kun Hu, Ph.D.
Limitations
The study’s limitations include the fact that polysomnography, which is the gold standard for sleep scoring, was not used, relying instead on actigraphy.
The participants were also older, so the findings might not translate to younger cohorts.
The authors recommend future studies to test whether directly intervening in daytime napping could lower the risk of Alzheimer’s dementia or cognitive decline.
If you care about brain health, please read studies about vitamin D deficiency linked to Alzheimer’s and vascular dementia, and higher magnesium intake could help benefit brain health.
For more information about brain health, please see recent studies about antioxidants that could help reduce dementia risk, and coconut oil could help improve cognitive function in Alzheimer’s.
The study was published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association.
Copyright © 2023 Knowridge Science Report. All rights reserved.
