Association between the Zhejiang University index and metabolic dysfunction-associated fatty liver disease as analyzed in National Health and Nutrition Examination Survey: A retrospective observational study

ObjectiveTo evaluate the association between the Zhejiang University index, a composite metabolic indicator, and the risk and severity of metabolic dysfunction-associated fatty liver disease.MethodsThis cross-sectional study utilized data from the National Health and Nutrition Examination Survey conducted from 1999 to 2020. The association between the Zhejiang University index and severity of metabolic dysfunction-associated fatty liver disease was analyzed using multivariable logistic regression, with adjustments made for confounding variables. Subgroup analyses were performed stratified by sex, age, diabetes, and hypertension status. The relationship with alcoholic liver disease was also verified. Multiple sensitivity analyses were conducted, including analyses of data before and after imputation.ResultsThe Zhejiang University index demonstrated a significant positive association with the incidence of metabolic dysfunction-associated fatty liver disease. The odds ratio increased from 1.74 (95% confidence interval: 1.70, 1.77; <i>p</i> < 0.001) in the crude model to 2.05 (95% confidence interval: 1.97, 2.15; <i>p</i> < 0.001) in the fully adjusted model. This association was more pronounced in nondiabetic subgroups and exhibited a threshold effect, diminishing when the Zhejiang University index exceeded 46.407. Sensitivity analyses, including the assessment of alcoholic liver disease, confirmed the robustness of these findings.ConclusionsThe Zhejiang University index is a promising and reliable tool for evaluating the risk of metabolic dysfunction-associated fatty liver disease. Further research into its clinical application could improve the risk stratification and management of metabolic dysfunction-associated fatty liver disease.