Circadian Misalignment Rather Than Sleep Duration is Associated with MAFLD: A Population-Based Propensity Score-Matched Study

BACKGROUND AND AIMS: Circadian misalignment (CM) leads to metabolic disorder. Metabolic (dysfunction) associated fatty liver disease (MAFLD) is a novel definition for fatty liver disease that requires the presence of metabolic dysfunction. As the association between CM and MAFLD remains unclear, this study is designed to explore whether there is an association between CM and MAFLD. METHODS: NHANES 2017–2018 database was used in this study. Liver steatosis and fibrosis were diagnosed by Fibroscan(®). CM was defined by the presence of mistimed sleep, late sleep or irregular chronotype. Propensity score matching (PSM) was used to match subjects for their age and gender. RESULTS: A total of 4552 participants were included in the study, with 2089 (45.89%) identified as MAFLD and 894 (19.64%) as CM. Participants with CM were significantly younger than those without (46.06 ± 18.06 vs 50.93 ± 17.78, p<0.001). PSM for age and gender resulted in 894 participants with CM and 892 with non-CM. CM group had higher body mass index, liver enzymes, glucose and lipid levels. The prevalence of MAFLD was higher in the CM group than the non-CM group (45.41% vs 28.48%, p<0.001). The presence of CM increased the risk of MAFLD by more than twofold. Short sleep duration (<6 hours) was not independently associated with MAFLD or fibrosis if additionally adjusting for CM. CONCLUSION: CM is independently associated with MAFLD, while short sleep duration (<6 hours) is not an independent risk factor for MAFLD or liver fibrosis after adjusting for CM.