Determinants of Change in Objectively Assessed Sleep Duration Among Older Men.

We examined potential risk factors for changes in objectively assessed sleep duration within a large sample of community-dwelling older men. Participants (n = 1,055; mean baseline age = 74.6 (standard deviation (SD), 4.7) years) had repeated ActiGraph assessments (ActiGraph LLC, Pensacola, Florida) taken at the baseline (2003-2005) and follow-up (2009-2012) waves of the Outcomes of Sleep Disorders in Older Men Study (an ancillary study to the Osteoporotic Fractures in Men (MrOS) Study conducted in 6 US communities). Among men with a baseline nighttime sleep duration of 5-8 hours, we assessed the odds of becoming a short-duration (<5 hours) or long-duration (>8 hours) sleeper at follow-up. The odds of becoming a short-duration sleeper were higher among men with peripheral vascular disease (adjusted odds ratio (aOR) = 6.54, 95% confidence interval (CI): 2.30, 18.55) and ≥1 impairment in Instrumental Activities of Daily Living (IADL) (aOR = 2.57, 95% CI: 0.97, 6.78). The odds of becoming a long-duration sleeper were higher among those with greater baseline age (per SD increment, aOR = 1.49, 95% CI: 1.12, 2.00), depression symptoms (aOR = 3.13, 95% CI: 1.05, 9.36), and worse global cognitive performance (per SD increment of Modified Mini-Mental State Examination score, aOR = 0.74, 95% CI: 0.58, 0.94). Peripheral vascular disease and IADL impairment, but not chronological age, may be involved in the etiology of short sleep duration in older men. The risk factors for long-duration sleep suggest that deteriorating brain health predicts elongated sleep duration in older men.