Objectives: Evaluate differences in sleep characteristics between older adults with and without mild Alzheimer's disease using waist-worn actigraphy monitors.
Methods: Actigraph GT3X+ monitors and self-reported sleep and activity logs were used for one week and compared between older adults (N = 85) with (n = 35) and without Alzheimer's disease (n = 51).
Results: Participants with Alzheimer's disease had greater total sleep time and spent more time in bed than nonimpaired older adults. Estimates for sleep efficiency and total sleep time for the total sample were elevated compared to previous studies of wrist-worn devices in similar populations, while estimates of sleep onset latency and wake after sleep onset for the total sample were lower.
Conclusions: Actigraphy-based sleep studies in older adults with Alzheimer's disease should consider discrepancies between objective and subjective estimates of sleep and monitor placement to maximize the ability to measure both activity and sleep.
Keywords: Actigraphy; Alzheimer’s disease; older adults; physical activity; sleep.