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Circadian Rhythms in AD pathogenesis: A Critical Appraisal
1Dept. of Neurology, Knight Alzheimer Disease Research Center, Washington University School of Medicine, St. Louis MO, USA.
Current Sleep Medicine Reports
|January 9, 2018
Summary
Circadian rhythm disruptions are common in Alzheimer's Disease (AD), but their role in early AD pathogenesis remains unclear. Future research should investigate if circadian dysfunction contributes to AD risk or progression.
Area of Science:
- Neuroscience
- Chronobiology
- Gerontology
Background:
- Alzheimer's Disease (AD) is associated with numerous sleep and circadian rhythm deficits.
- Most studies focus on late-stage AD, limiting understanding of early pathogenesis.
- The potential role of circadian dysfunction in AD development is under-investigated.
Purpose of the Study:
- To review evidence on the hypothesis that circadian dysfunction is integral to early AD pathogenesis or risk.
- To identify gaps in current knowledge regarding circadian rhythms and AD.
- To propose future research directions for clarifying the role of circadian clock dysfunction in AD.
Main Methods:
- Literature review of studies on circadian function in early-stage or preclinical AD.
- Analysis of evidence linking circadian disruption to AD risk.
- Identification of research needs to establish causality.
Main Results:
- Few studies examine circadian function in preclinical or very early AD.
- Current research lacks AD biomarkers in studies of cognitively normal or early AD individuals.
- The cause-and-effect relationship between circadian dysfunction and early AD remains undetermined.
Conclusions:
- Circadian rhythm deterioration is evident as AD dementia progresses.
- The precise timing of rhythm impairment in AD pathogenesis is unknown.
- Whether middle-age circadian disruption elevates later AD risk requires further investigation.
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