LAUSR

BACKGROUND The association of sleep habits with "advancing age among older adults" is not fully understood. OBJECTIVES The purpose of the present study was to examine the association of sleep habits with advancing age among community-dwelling older adults in Japan. METHODS A total of 18,005 older people (mean age: 73.2 ± 6.0 years; 8,070 men and 9,935 women) from the National Center for Geriatrics and Gerontology Study of Geriatric Syndromes were analyzed. Participants were asked in face-to-face interviews about the times they usually go to bed, fall asleep, wake-up, and get up. The amount of time spent in bed and self-reported sleep duration were then calculated from the differences between these times. As other parameters, the subjects were also asked about sleep latency, time spent in bed after waking up, number of nocturnal awakenings, and duration of napping in a typical day. RESULTS The results of the Jonckheere-Terpstra test showed that all sleep parameters shifted to an earlier time (going to bed, falling asleep, waking up, and getting out of bed), longer duration (sleep duration, time spent in bed, sleep latency, time spent in bed after waking up, and napping), or more nocturnal awakenings with advancing age (all p < 0.01). Among the men, the time of waking up was not significantly associated with age, while among the women, the time of getting up was not significantly associated with age. CONCLUSION These results from a large cohort show the age-related trends of sleep habits in community-dwelling older adults in Japan. Our results revealed that a longer duration and earlier timing of sleep are associated with advancing age.