Association Between Metabolic Obesity Phenotypes and Alcohol-Associated Fatty Liver Disease Among US Adults: A NHANES 2013–2018 Analysis

Background: Alcohol-associated fatty liver disease (AFLD) is a major public health concern and remains one of the leading causes of chronic liver disease in the United States. Understanding the interplay between obesity, metabolic dysfunction, and lifestyle factors may help identify populations at increased risk for AFLD. Methods: This cross-sectional study utilized data from the National Health and Nutrition Examination Survey (NHANES) collected between 2013–2018. AFLD was operationally defined using elevated liver enzyme levels combined with risky alcohol consumption. Metabolic obesity phenotypes (MOPs) were characterized by combining body mass index categories with either metabolic health status or metabolic syndrome (MS). Results: The weighted prevalence of AFLD was 14% (95%CI: 12–16%). AFLD prevalence was significantly higher among males than females (17% vs. 10% respectively, p < 0.0001), and among Hispanics compared to Non-Hispanic Black participants (20% vs. 9% respectively, p < 0.0001). Compared with metabolically healthy normal-weight individuals, obese participants with MS demonstrated the strongest association overall AFLD association (adjusted PR: 6.73; 95% CI: 4.51–10.05). Furthermore, obese males with MS showed the highest odds of AFLD under both MOP schemes (MOP 1: OR: 8.19; 95% CI: 4.41–15.23; MOP 2: OR: 10.92; 95% CI: 6.86–17.37). Conclusions: Individuals with obesity and metabolic dysfunction demonstrated significantly higher AFLD prevalence compared with metabolically healthy normal-weight individuals. MOPs incorporating MS demonstrated stronger associations with AFLD than classifications based on metabolic health status alone. These findings support the importance of screening strategies that address both obesity and metabolic dysfunction in addition to alcohol use to better identify high-risk populations.