Abstract
BACKGROUND: Comparative analyses of metabolic biomarkers for Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) in young adults remain limited. While previous studies have examined metabolic predictors of MASLD, few have specifically focused on young adult populations in China, where rising obesity rates and lifestyle changes are creating new patterns of metabolic risk. METHODS: In this retrospective study, young adults underwent abdominal ultrasounds and metabolic profiling were included in the analysis. Eleven blood lipid and glucose profiles were analyzed. MASLD is defined according to the liver ultrasound findings and self-reported alcohol consumption. Multivariable logistic regression and ROC curves were employed to analyze the association between each indicator and the outcome. Based on the five indicators most strongly indicators, the number of major risk factors for patients was defined, and a logistic regression model with adjusted covariates was used to investigate the impact of the coexistence of risk factors on MASLD. RESULTS: A total of 24.55% (n=10,332) of participants aged 35 years and under had MASLD. All indicators were significantly associated with MASLD separately after adjusting for covariates. Elevated TG/HDL-C ratio≥ 1.44 (OR: 3.87, 95% CI:3.62, 4.15), TyG ≥ 8.8 (OR: 3.78, 95% CI: 3.51, 4.07), and TG≥ 1.61mmol/L (OR: 3.62, 95% CI: 3.38, 3.88) exhibited the strongest associations with MASLD. ROC analysis indicated comparable predictive performance for TG/HDL ratio (AUC: 0.85, 95% CI:0.84, 0.85) and TyG (AUC: 0.83, 95% CI:0.83, 0.84). Cumulative risk factor analysis indicated that individuals with more risk factors suffered increasing risk compared to those with no risk factors. The associations were stable among participants with different amount of metabolic risk factors. CONCLUSION: Our study establishes that lipid ratios and insulin resistance indices maintain strong predictive value for MASLD in young Chinese adults, even when traditional metabolic risk factors are absent. These findings highlight the importance of incorporating TG/HDL-C ratio and TyG index into routine health screenings for early MASLD detection in young populations.