Non-insulin metabolic indices for assessing insulin resistance in medical students

Objective Insulin resistance (IR) is a metabolic abnormality associated with metabolic syndrome and type 2 diabetes mellitus and has been increasingly recognized among young adults, including medical students. However, assessing IR using insulin-based measurements is often limited in routine practice, highlighting the need for simple non–insulin-based metabolic indices. This study aimed to evaluate and compare the diagnostic performance of these indices for identifying IR using HOMA-IR as the reference standard, among medical students. Methods This cross-sectional study included 235 medical students aged ≥18 years. After a 10-hour overnight fast, venous blood samples were collected to assess fasting glucose, lipid profiles, and insulin levels. Anthropometric measurements were performed to determine body mass index and waist circumference. The diagnostic performance of non–insulin-based indices (TyG, TG/HDL-C, TyG-BMI, MetS-IR, LAP, and SPISE) was evaluated against HOMA-IR using receiver operating characteristic (ROC) curve analysis. Results ROC analysis demonstrated that the evaluated non–insulin-based indices showed fair discriminative performance, with AUC values ranging from 0.59 to 0.69. Among these indices, LAP demonstrated the highest AUC and the highest specificity (77.97%), whereas TyG showed the highest sensitivity (77.36%). Conclusions Non–insulin-based metabolic indices demonstrated fair discriminatory performance for identifying insulin resistance. Among the evaluated indices, LAP showed the highest AUC and specificity, whereas TyG exhibited the highest sensitivity. Overall, LAP and TyG demonstrated relatively better discriminatory performance than the other evaluated indices; however, further validation in larger, population-specific studies is required before clinical implementation.