Metabolic dysfunction-associated fatty liver disease and liver fibrosis: prevalence and associated factors in the middle-aged and older U.S. population

BACKGROUND The global burden of chronic liver disease is substantial. Limited studies have reported the prevalence of metabolic dysfunction-associated fatty liver disease (MAFLD) and liver fibrosis among middle-aged and older people. Therefore, we aimed to determine the nationwide prevalence of and associated factors for MAFLD and fibrosis in the U.S. adults aged 45-79 years. METHODS This cross-sectional study utilized data from the 2017-2018 cycle of the National Health and Nutrition Examination Survey (NHANES) conducted with a nationally representative sample of civilian, noninstitutionalized U.S. POPULATION Hepatic steatosis and fibrosis were assessed by transient elastography with controlled attenuation parameter and liver stiffness measurement, respectively. RESULTS A total of 1,186 eligible participants aged 45-79 years were finally included in the analyses. The estimated prevalence of MAFLD, significant fibrosis (F ≥ F2), and advanced fibrosis (F ≥ F3) was 48.6% (95% confidence interval [CI]: 43.1-54.0%), 9.5% (95% CI: 6.8-12.7%), and 6.7% (95% CI: 4.1-10.1%), respectively. Multivariable logistic regression revealed an increased MAFLD predisposition in subjects with metabolic disorders including overweight/obesity, abdominal obesity, hypertension, and diabetes mellitus. Moreover, the presence of depression was an independent and strong predictor of MAFLD risk (OR=3.23, 95% CI: 1.37-7.11). Elevated liver enzymes, hypertension, diabetes mellitus, hepatitis virus infection, and steatosis were associated with a high risk of significant fibrosis. CONCLUSIONS Newly defined MAFLD is highly prevalent in the U.S. middle-aged and older population. Approximately one in ten people has significant liver fibrosis. In addition to metabolic disorders, the presence of depression potentially increase the risk of MAFLD. This article is protected by copyright. All rights reserved.