Nighttime sleep duration and risk of nonalcoholic fatty liver disease: the Dongfeng-Tongji prospective study

To examine the association between self-reported nighttime sleep duration and nonalcoholic fatty liver disease (NAFLD) risk by comparing the incidence rates of NAFLD among healthy subjects with different sleep duration during the 5 years follow-up.8965 eligible NAFLD-free subjects with a mean age of 61.6 years (males, 43.4%) from Dongfeng-Tongji cohort study at baseline were enrolled in the study. Logistic regression analysis was used to estimate the association between sleep duration and incident NAFLD with potential confounders adjusted. Sleep duration was categorized into five groups: <6 h, 6-7 h, 7-8 h, 8-9 h, ≥9 h.During the 5-years of follow-up, a total of 2,197 participants were newly diagnosed as NAFLD. Compared with those reported 7-8 h per day of nighttime sleep, the multivariable-adjusted odds ratio (95% confidence intervals) were 1.21 (1.07-1.38) for those who sleep 8-9 h/day, and 1.31 (1.13-1.52) for those who sleep over 9 h/day. However, no significant association was found with short nightly sleep duration (<7 h/day).Long nighttime sleep duration was associated with a modestly increased risk of NAFLD in a middle-aged and elderly Chinese population. Key messages Long nighttime sleep duration was associated with a modestly increased risk of NAFLD in a middle-aged and elderly Chinese population. The effect of long nighttime sleep on the risk of incident NAFLD was attenuated greatly by body mass index (BMI) in men.