0352 Seasonal Changes in Sleep Duration and Sleep Problems: A Prospective Study in Japanese Community Residents

Abstract Introduction Scientific understanding of seasonal effects on sleep and sleep problems has yet to be elucidated, although it may help to establish an optimal sleep hygiene program to treat sleep problems such as insomnia and hypersomnia. Here we investigated seasonal changes in sleep duration and sleep problems, as well as the effects of age, in Japanese community residents. Methods Data on 1,388 individuals aged 15–89 years, who participated in the Survey of Seasonal Changes in Diet and Lifestyles conducted by the National Institute of Health and Nutrition of Japan (2004–2006), were analyzed. A self-administered questionnaire included items on sleep duration and sleep problems (difficulty initiating sleep [DIS], difficulty maintaining sleep [DMS]/early morning awakening [EMA], and excessive daytime sleepiness [EDS]). Data were prospectively collected at four time points (spring, summer, fall, and winter). Results Seasonal changes in sleep duration were found, with the longest in winter and the shortest in summer (mean winter-summer difference: 0.18 ± 0.91 hours). When analyzed according to age group, seasonal changes in sleep duration were found in the middle and old age groups, but not in the young age group. Seasonal changes in the frequencies of DIS, DMS/EMA, and EDS were found, and the prevalences of clinically significant DIS, DMS/EMA, and EDS were all highest in spring. When analyzed according to age group, seasonal changes in the frequencies of sleep problems were found for some items in the young age group (DMS/EMA and EDS) and middle age group (DIS and DMS/EMA); however, no seasonal changes in sleep problems were observed in the old age group. Conclusion The present study found seasonal effects on sleep and sleep problems in Japanese community residents, but the effects varied among age groups. Support (If Any):