1149 Late-Life Trajectories of Nighttime Sleep Duration and Daytime Napping in Relation to Neuropathologic Markers at Death: The Honolulu-Asia Aging Study

Abstract Introduction Prior studies on sleep duration and dementia-related neuropathology have primarily relied on self-reports from a single time point, and did not consider daytime napping, a common compensatory mechanism for inefficient nighttime sleep among older adults. Methods Our study included 533 Japanese-American men from the Honolulu-Asia Aging Study (HAAS) who self-reported their nighttime sleep duration and daytime napping (in minutes) on at least two of the four exams between 1991–2000, died before 2010 and participated in the HAAS Autopsy Study. We identified three trajectory groups for sleep duration and napping separately using group-based trajectory modeling with time before death as the timescale. Multivariable logistic regression was used to estimate the odds ratio (OR) and 95% CI for the presence of neuropathologic lesions according to the trajectory groups, adjusting for age at death and baseline factors including age, cognitive scores, smoking status, physical activity, BMI, systolic blood pressure, fasting glucose, total and HDL cholesterol. Results The mean age (range) was 77 years (71–92) at baseline and 91 years (range: 83–104) at death. Compared with the medium-stable sleep duration group, the long-increasing group had increased odds for the presence of Lewy bodies (OR: 2.28, 95% CI: 1.27–4.08), Braak stages V/VI (OR: 1.83, 95% CI: 1.08–3.10), and neuritic plaques (OR: 1.51, 95% CI: 0.91–2.49); no associations were observed for the short-decreasing group. In contrast, compared with the none-minimum napping group, both moderate-increasing and long-increasing groups had lower odds of microinfarcts, Braak stages V/VI, and neuritic plaques. For example, the OR (95% CI) for neuritic plaques was 0.55 (0.35–0.87) for the moderate-increasing group and 0.46 (0.21–1.03) for the long-increasing group, respectively. Neither sleep duration nor napping trajectories were associated with brain atrophy. Conclusion In older Japanese-American men, a long-increasing trajectory of self-reported sleep duration was associated with an increased likelihood of Lewy body and Alzheimer’s neuropathology, whereas both moderate-increasing and long-increasing napping trajectories were associated with a lower likelihood of brain lesions implicated in vascular and Alzheimer’s neuropathology. Ongoing analyses are exploring the joint associations of sleep duration and napping trajectories with neuropathologic outcomes. Support (if any) NIA Intramural Research Project ZIAAG000530