1141 EXCESSIVE DAYTIME SLEEPINESS, NAPPING, AND BRAIN AMYLOID IN OLDER ADULTS

Abstract

Introduction:

Excessive daytime sleepiness (EDS) and napping are related and both have been linked to poor cognitive outcomes. However, little is known about their association with Alzheimer’s disease pathology. We determined the association of EDS and napping with β-amyloid (Aβ) deposition in community-dwelling older adults.

Methods:

We studied 124 participants in the Baltimore Longitudinal Study of Aging (mean age ±SD = 60.1 years ±9.8; education = 16.7 ± 2.2 years; 50.8% women; 21.8% non-White) with measures of EDS and/or napping who completed Pittsburgh Compound B positron emission tomography 15.7 ± 3.4 years later. Participants reported whether they often become drowsy and fall asleep when they want to be awake and frequency of napping. Those responding “yes” to the former were considered to have EDS, and those napping more than “never” were considered nappers. PET cortical distribution volume ratios >1.06 were considered Aβ-positive (Aβ+).

Results:

Of the 124 participants, 30 (24.4%) reported EDS, 35 (28.5%) reported napping, and 43 (34.7%) were Aβ+. In unadjusted analyses, participants with EDS had over three times the odds of being Aβ+ (odds ratio (OR) = 3.37, 95% confidence interval (CI) 1.44, 7.90, p = 0.005), compared to those without. This remained significant after adjustment for age, body mass index, and education (OR = 2.58, 95% CI 1.03, 6.45, p = 0.043). Nappers had twice the odds of being Aβ+, but this did not reach significance in unadjusted (OR = 2.01, 95% CI 0.90, 4.50, p = 0.091) or adjusted (OR = 1.84, 95% CI 0.76, 4.47, p = 0.18) analyses.

Conclusion:

EDS is associated with an increased odds of amyloid deposition more than a decade later. Prospective studies with polysomnography and repeated measures of Aβ will clarify whether sleep-disordered breathing or another factor drives this association, or if EDS is a marker of preclinical Alzheimer’s disease.

Support (If Any):

This study was supported by Research and Development Contract HHSN-260-2004-00012C, R01AG050507, and 1RF1AG050745, and in part by the Intramural Research Program of the National Institute on Aging, NIH.