Short sleep duration reduces the risk of nonalcoholic fatty liver disease onset in men: a community-based longitudinal cohort study

Background Epidemiologic studies show an association between short sleep duration and the presence of nonalcoholic fatty liver disease (NAFLD). This study examined the association between short sleep duration and the onset of NAFLD. Methods This community-based, retrospective, longitudinal cohort study included 6,370 Japanese subjects who had undergone annual health check-ups more than twice at a single center between April 2003 and March 2010. After excluding 3,941 subjects, the records of 2,429 Japanese subjects were reviewed. Results Two groups comprised the study cohort: those with short (≤6 h) sleep durations ( n = 1,543) and those with moderate (7–8 h) sleep durations ( n = 886). During the observation period, 296 subjects developed NAFLD. Multivariate analysis identified an association between short sleep duration and the reduced onset of NAFLD in men (odds ratio: 0.551, 95 % confidence interval 0.365–0.832, p = 0.005). There was no association between short sleep duration and NAFLD onset in women. The prevalence of NAFLD onset in men increased significantly as sleep duration increased, as follows: 12.5, 18.4, and 27.4 % among subjects who had sleep durations of ≤4, 5–6, and 7–8 h, respectively ( p = 0.02). Conclusions This study demonstrates an association between sleep duration and NAFLD onset. Short sleep duration reduced the risk of NAFLD onset in men. Correct recognition is important to prevent disease progression and further complications.