Metabolic dysfunction‐associated fatty liver disease and liver fibrosis: Prevalence and associated factors in the middle‐aged and older US population

AIM 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 adults aged 45-79 years from the United States. METHODS This cross-sectional study utilized data from the 2017-2018 cycle of the National Health and Nutrition Examination Survey conducted with a nationally representative sample of the civilian, noninstitutionalized US population. Hepatic steatosis and fibrosis were assessed by transient elastography with controlled attenuation parameter and liver stiffness measurement, respectively. RESULTS A total of 1186 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 (odds ratio = 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 US middle-aged and older population. Approximately 1 in 10 people has significant liver fibrosis. In addition to metabolic disorders, the presence of depression potentially increases the risk of MAFLD.