Diagnostic performance of METS-IR versus conventional metabolic indices for insulin resistance and MASLD in adolescents

The prevalence of insulin resistance (IR) and metabolic dysfunction-associated steatotic liver disease (MASLD) has risen markedly among children and adolescents in recent years. Traditional noninvasive metabolic surrogate markers developed for adult populations have shown inconsistent performance and limited applicability during puberty. To compare the discriminative performance of the metabolic score for insulin resistance (METS-IR), the triglyceride-glucose (TyG) index, and the TG/HDL-C ratio in identifying IR and MASLD among adolescents. This cross-sectional study included 257 adolescents aged 10–18 years. The discriminative value of various metabolic indices for IR and MASLD was evaluated using receiver operating characteristic (ROC) curve analysis, multivariate logistic regression, and Spearman correlation analysis. For IR identification, METS-IR demonstrated the most effective discriminative ability, with an area under the curve (AUC) of 0.736 and an optimal cutoff of 46.68 (sensitivity 52.9%, specificity 94.7%). Conversely, neither the TyG index (AUC = 0.550) nor the TG/HDL-C ratio (AUC = 0.516) reached statistical significance. For MASLD identification, all three indices showed significant discriminative value, with METS-IR remaining the highest numerical AUC (AUC = 0.705; optimal cutoff value: 42.60; sensitivity: 75.8%; specificity: 57.6%), although DeLong’s test showed no significant difference from the TyG index ( P = 0.524). The AUCs for the TyG index and the TG/HDL-C ratio were 0.669 and 0.631, respectively. After adjusting for age, sex, and other potential confounders, multivariate logistic regression showed that METS-IR remained independently associated with both IR (OR = 1.100, 95% CI 1.025–1.180) and MASLD (OR = 1.087, 95% CI 1.014–1.165). METS-IR demonstrated better discriminative performance in identifying IR and MASLD in adolescents than conventional metabolic indices such as the TyG index and the TG/HDL-C ratio. Integrating adiposity and glycolipid metabolic parameters may enhance the ability of METS-IR to reflect the metabolic characteristics of puberty. These findings warrant further prospective validation in general adolescent populations prior to clinical application.