Significant burden of nonalcoholic fatty liver disease with advanced fibrosis in the US: a cross-sectional analysis of 2011-2014 National Health and Nutrition Examination Survey.

Abstract

Nonalcoholic fatty liver disease (NAFLD) is a leading cause of chronic liver disease in the US. Understanding the epidemiology of NAFLD, with specific focus on individuals with hepatic fibrosis is important to guide healthcare resource planning. To evaluate prevalence and predictors of hepatic fibrosis among US adults with NAFLD. We performed a cross-sectional study using data from the updated 2011-2014 National Health and Nutrition Examination Survey, a national, stratified, multistage sampling survey of non-institutionalised US adults age ≥ 20. METAVIR F2 or greater fibrosis among individuals with NAFLD was assessed using AST to Platelet Ratio Index (APRI) score > 0.7. METAVIR F3 or greater fibrosis was assessed using NAFLD fibrosis score (NFS) > 0.676 and FIB-4 score > 3.25. Multivariate logistic regression models evaluated for predictors of fibrosis among individuals with NAFLD. Overall prevalence of NAFLD among US adults was 21.9% (95% CI 20.6-23.3), representing 51.6 million adults. Among individuals with NAFLD, we observed a 23.8% prevalence of ≥F2 fibrosis, representing 12.2 million individuals, and we observed a 2.3%-9.7% prevalence of ≥F3 fibrosis, representing as many as 5.0 million adults. On multivariate regression analyses, increasing age, obesity and concurrent diabetes mellitus were associated with increased risk of ≥F3 fibrosis. NAFLD represents a major healthcare burden among US adults with as many as 5 million adults estimated to have NAFLD with ≥F3 fibrosis. Age and the components of the metabolic syndrome are independently associated with higher risk of fibrosis.