Division of Epidemiology, Department of Public Health and Forensic Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan.
Sleep Med. 2013 Feb;14(2):206-10. doi: 10.1016/j.sleep.2012.09.024. Epub 2012 Dec 4.
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.
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.
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.
Among community-dwelling Japanese, only obese long sleepers have a significantly increased long-term risk of ⩾5kg weight gain.
尽管先前的研究表明睡眠时间的长短对体重增加的风险有长期影响，但西方人群无论睡眠时间长短，往往都会随着时间的推移而体重增加。相反，研究表明日本人的 BMI 在较长时间内会下降，因此，睡眠时间的长短对体重增加和肥胖的长期影响在亚洲仍不清楚。
我们随访了 13629 名年龄在 40-79 岁的参与者，并从 1995 年至 2006 年期间前瞻性地收集数据。我们根据参与者自我报告的睡眠时间将其分为五组：⩽5 小时（短睡眠）、6 小时（参考）、7 小时、8 小时和 ⩾9 小时（长睡眠）。主要结局是 ⩾5kg 的体重增加或 BMI ⩾25kg/m(2)（肥胖）。我们使用逻辑回归分析得出优势比（OR）和 95%置信区间（CI），并调整了几个混杂因素。
我们没有发现睡眠时间与 ⩾5kg 体重增加和肥胖风险之间存在关联。在 BMI 分层后，肥胖参与者中长睡眠者 ⩾5kg 体重增加的风险显著增加（OR：1.36，95%CI：1.09-1.70）。
在社区居住的日本人中，只有肥胖的长睡眠者有明显增加的 ⩾5kg 体重增加的长期风险。
