Associations between sarcopenia and nonalcoholic fatty liver disease and advanced fibrosis in the USA

Background and aim Nonalcoholic fatty liver disease (NAFLD) may be associated with sarcopenia. This study aims to determine whether sarcopenia is independently associated with NAFLD and advanced fibrosis. Participants and methods Cross-sectional data from 11 325 participants in the third National Health and Nutrition Examination Survey were analyzed. NAFLD was defined as the presence of hepatic steatosis from the ultrasound. Sarcopenia was defined as the skeletal muscle index. Results NAFLD was more common in participants with sarcopenia than in those without (46.7 vs. 27.5%). Univariate analysis showed that sarcopenia was associated with NAFLD [odds ratio (OR): 2.31; 95% confidence interval (CI): 2.01-2.64], which remained significant after adjustment for age, sex, ethnicity, metabolic risk factors (OR: 1.24; 95% CI: 1.03-1.48). This finding persisted after adjustment for C-reactive protein as a marker of chronic inflammation. NAFLD-associated advanced fibrosis was more common in participants with sarcopenia than in those without (7.8 vs. 1.6%). Sarcopenia was associated with NAFLD-associated advanced fibrosis independent of metabolic risk factors (OR: 1.79; 95% CI: 1.18-2.72). Conclusion Sarcopenia was independently associated with increased odds of NAFLD and NAFLD-associated advanced fibrosis independent of well-defined risk factors. Interventions to strengthen muscle mass may reduce the burden of NAFLD and advanced fibrosis.