In adults, short sleep duration and late bedtime were associated with hyperglycemia and obesity, but these relationships in children are little known. We evaluated the association of bedtime and sleep duration with overweight/obesity or hyperglycemia in children by sex, considering the effects of diet, physical activity, and screen time. A cross-sectional study was conducted for 1139 Japanese children (553 boys) aged 10-y. Overweight was as defined by the International Obesity Task Force. Cutoff value for hyperglycemia was HbA1c ≥5.6%. Variables associated with hyperglycemia or overweight were based on logistic regression analysis. Multivariate logistic regression analysis showed that compared with an early bedtime (˜21:59) and long sleep duration (weekdays ≥8.67 h, weekends ≥9 h) , short sleep duration (weekdays <8.67 h, weekends <9 h) was associated with overweight in boys but not late bedtimes (22:00˜) . The significant association seen disappeared in girls when adjusted for screen time. For hyperglycemia, in both sexes wake time and sleep duration on weekends were significant in univariate analysis, but not in multivariate analysis adjusted for diet and physical activity. In Japanese boys, short sleep duration was significantly associated with overweight. Sleep ≥8.67 on weekdays and ≥9 h on weekends may be essential to prevent overweight. Table. Adjusted odds ratios for overweight


H. Shiozaki: None. K. Fujihara: None. M.H. Yamada: None. T. Osawa: None. M. Kitazawa: None. M. Yamamoto: None. T. Sato: None. T. Yamada: None. H. Sone: Research Support; Astellas Pharma Inc., Eisai Co., Ltd., Kyowa Kirin Co., Ltd., Novo Nordisk, Ono Pharmaceutical Co., Ltd., Taisho Pharmaceutical Holdings Co., Ltd., Takeda Pharmaceutical Company Limited.


Patient Centered Outcomes Research Institute

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