Daily sedentary behavior exceeding 5 hours is independently associated with MAFLD: a cross-sectional study from NHANES 2017-2020.

Abstract

Introduction: Metabolic dysfunction-associated fatty liver disease (MAFLD) has emerged as a predominant global cause of chronic liver disease, linked to various health issues. Although sedentary behavior (SB) has been associated with MAFLD, an exact upper limit for sedentary time has not been established. This study aimed to investigate the dose-response relationship between sedentary time and MAFLD and identify potential reference values for future research and recommendations.

Material and methods: The study analyzed 7,705 participants from the 2017-2020 NHANES cycle, using transient elastography to identify MAFLD and liver fibrosis or cirrhosis. Sedentary time and physical activity levels were determined through a detailed questionnaire, with physical activity classified by official guidelines. Restricted cubic spline and piecewise regression analyses examined the association between sedentary time and MAFLD.

Results: Sedentary time demonstrated a linear dose-response relationship with MAFLD (p for non-linear = 0.647, p overall < 0.001), with sedentary behavior over 5 h daily significantly associated with higher odds of MAFLD. After adjustment for confounders, each additional sedentary hour was associated with a 7.7% increase in the odds of MAFLD (p < 0.001). Males had a higher prevalence of MAFLD, liver fibrosis, and cirrhosis than females (p < 0.001). Further analysis revealed no significant difference by sex in the association between sedentary time and MAFLD (p for interaction = 0.0974).

Conclusions: Prolonged sedentary time is associated with higher odds of MAFLD in US adults. Reducing excessive sedentary behavior may represent a potential strategy for MAFLD prevention, although further longitudinal studies are needed to establish evidence-based sedentary time recommendations.