Physical activity and advanced fibrosis in MASLD, MetALD, and ALD in a nationally representative cohort: NHANES 2017–2020

Background: It is unclear whether physical activity (PA) and advanced fibrosis are associated in alcohol-associated liver disease (ALD) and metabolic dysfunction and alcohol-associated liver disease (MetALD). We examined the association between work-related PA (WPA) or leisure-time PA (LTPA) and advanced fibrosis across the steatotic liver disease (SLD) spectrum. Methods: Data obtained from the National Health and Nutrition Examination Survey (2017-2020) in adults with hepatic steatosis were included and categorized into MASLD (n=2236), MetALD (n=1355), and ALD (n=457) based on alcohol use. PA was quantified as metabolic equivalent (MET)-minutes per week, and ≥600 MET-min/wk was used as the threshold for high activity. Adjusted logistic regression models for confounders (sex, race/ethnicity, education, income, metabolic risk factors, and etiology of SLD) were used to analyze the relationship of PA types with at-risk advanced fibrosis, according to an Agile 3+ score ≥0.45. Results: Among 4342 SLD participants, LTPA was strongly linked to a lower risk of at-risk advanced fibrosis in MASLD (OR=0.56, 95% CI: 0.34–0.93), as well as MetALD and ALD combined (OR=0.55, 95% CI: 0.34–0.89). WPA was not associated with improved advanced fibrosis. There were no interactions between WPA and SLD subtypes ( p =0.98), and between LTPA and SLD subtypes ( p =0.55). Conclusions: LTPA but not WPA is protective for at-risk advanced fibrosis in patients with MASLD and MetALD. These findings showcase the importance of structured LTPA interventions to mitigate fibrosis risk in SLD. Larger studies are needed to examine the benefits of PA in patients with ALD and to delineate exercise prescriptions for patients with SLD.