Self-reported sleep and β-amyloid deposition in community-dwelling older adults.

IMPORTANCE

Older adults commonly report disturbed sleep, and recent studies in humans and animals suggest links between sleep and Alzheimer disease biomarkers. Studies are needed that evaluate whether sleep variables are associated with neuroimaging evidence of β-amyloid (Aβ) deposition. OBJECTIVE To determine the association between self-reported sleep variables and Aβ deposition in community-dwelling older adults.

DESIGN, SETTING, AND PARTICIPANTS: Cross-sectional study of 70 adults (mean age, 76 [range, 53-91] years) from the neuroimaging substudy of the Baltimore Longitudinal Study of Aging, a normative aging study. EXPOSURE Self-reported sleep variables. MAIN OUTCOMES AND MEASURES β-Amyloid burden, measured by carbon 11-labeled Pittsburgh compound B positron emission tomography distribution volume ratios (DVRs).

RESULTS

After adjustment for potential confounders, reports of shorter sleep duration were associated with greater Aβ burden, measured by mean cortical DVR (B = 0.08 [95% CI, 0.03-0.14]; P = .005) and precuneus DVR (B = 0.11 [0.03-0.18]; P = .007). Reports of lower sleep quality were associated with greater Aβ burden measured by precuneus DVR (B = 0.08 [0.01-0.15]; P = .03).

CONCLUSIONS AND RELEVANCE

Among community-dwelling older adults, reports of shorter sleep duration and poorer sleep quality are associated with greater Aβ burden. Additional studies with objective sleep measures are needed to determine whether sleep disturbance causes or accelerates Alzheimer disease.