BACKGROUND: Although previous studies showed the long-term effects of sleep duration on risk of weight gain, Western tends to gain weight irrespective of sleep duration over a long period. Conversely, it is showed that body mass index (BMI) decreases during a long period in Japanese and thus, the long-term effect of sleep duration on weight gain and obesity is still unclear in Asia. METHODS: We followed up 13,629 participants aged 40-79years and prospectively collected data from 1995 to 2006. We divided the participants into five groups according to their self-reported sleep duration: ⩽5h (short sleep), 6h, 7h (reference), 8h, and ⩾9h (long sleep). The main outcome was ⩾5kg weight gain or BMI⩾25kg/m(2) (obesity). We used logistic regression analyses to derive odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for several confounding factors. RESULTS: We observed no association between sleep duration and risk of ⩾5kg weight gain and obesity. After stratification by BMI, long sleepers had a significantly increased risk of ⩾5kg weight gain (OR: 1.36, 95%CI: 1.09-1.70) in obese participants. CONCLUSIONS: Among community-dwelling Japanese, only obese long sleepers have a significantly increased long-term risk of ⩾5kg weight gain.
BACKGROUND: Although previous studies showed the long-term effects of sleep duration on risk of weight gain, Western tends to gain weight irrespective of sleep duration over a long period. Conversely, it is showed that body mass index (BMI) decreases during a long period in Japanese and thus, the long-term effect of sleep duration on weight gain and obesity is still unclear in Asia. METHODS: We followed up 13,629 participants aged 40-79years and prospectively collected data from 1995 to 2006. We divided the participants into five groups according to their self-reported sleep duration: ⩽5h (short sleep), 6h, 7h (reference), 8h, and ⩾9h (long sleep). The main outcome was ⩾5kg weight gain or BMI⩾25kg/m(2) (obesity). We used logistic regression analyses to derive odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for several confounding factors. RESULTS: We observed no association between sleep duration and risk of ⩾5kg weight gain and obesity. After stratification by BMI, long sleepers had a significantly increased risk of ⩾5kg weight gain (OR: 1.36, 95%CI: 1.09-1.70) in obeseparticipants. CONCLUSIONS: Among community-dwelling Japanese, only obese long sleepers have a significantly increased long-term risk of ⩾5kg weight gain.
Authors: Nathaniel F Watson; M Safwan Badr; Gregory Belenky; Donald L Bliwise; Orfeu M Buxton; Daniel Buysse; David F Dinges; James Gangwisch; Michael A Grandner; Clete Kushida; Raman K Malhotra; Jennifer L Martin; Sanjay R Patel; Stuart F Quan; Esra Tasali Journal: J Clin Sleep Med Date: 2015-08-15 Impact factor: 4.062
Authors: Nathaniel F Watson; M Safwan Badr; Gregory Belenky; Donald L Bliwise; Orfeu M Buxton; Daniel Buysse; David F Dinges; James Gangwisch; Michael A Grandner; Clete Kushida; Raman K Malhotra; Jennifer L Martin; Sanjay R Patel; Stuart F Quan; Esra Tasali Journal: Sleep Date: 2015-08-01 Impact factor: 5.849
Authors: Michael D Wirth; James R Hébert; Gregory A Hand; Shawn D Youngstedt; Thomas G Hurley; Robin P Shook; Amanda E Paluch; Xuemei Sui; Shelli L James; Steven N Blair Journal: Ann Epidemiol Date: 2015-05-14 Impact factor: 3.797