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Updated: Aug 14, 2026

Collecting Sleep, Circadian, Fatigue, and Performance Data in Complex Operational Environments
Published on: August 8, 2019
Age changes in timing and 24-hour distribution of self-reported sleep
Donald L Bliwise1, Farzaneh Pour Ansari, Laura-Beth Straight
1Program in Sleep, Aging, and Chronobiology, Wesley Woods Health Center, Emory University Medical School, 1841 Clifton Road NE, Atlanta, GA 30329, USA. dbliwis@emory.edu
Objective:
Aging has been associated with increased nocturnal awakenings, increased napping, earlier bedtimes and wake-up times, and more regular sleep-wake schedules. These patterns have often been ascribed to both psychosocial and medical factors, but nearly all studies to-date have been cross-sectional.
Methods:
The authors present self-reported sleep data from 31 elderly subjects followed over a decade.
Results:
With aging, the number of nightly awakenings and daytime napping increased over time. Exploratory analyses suggested that individuals who lived with another person had earlier bedtimes, later wake-up times, and greater daytime napping. Intervening medical comorbidities also appeared to be associated with increased napping.
Conclusion:
These results confirm previous cross-sectional studies and suggest a complex biopsychosocial matrix for the timing and placement of sleep in elderly persons within the 24-hour day.
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