Assessment of Various Insulin Resistance Surrogate Indices in Thai People with Type 2 Diabetes Mellitus

Objective. To compare insulin surrogate indices with the homeostasis model assessment of insulin resistance (HOMA-IR) in Thai people with type 2 diabetes (T2D). Methodology. A cross-sectional study of 97 individuals with T2D was done to determine the association between HOMAIR and seven surrogate indices for insulin resistance. IR was defined as HOMA-IR >= 2.0. The indices included Waist Circumference (WC), Waist-to-Hip Ratio (WHR), Waist-to-Height Ratio (WHtR), Triglyceride-Glucose (TyG) index, estimated Glucose Disposal Rate (eGDR) calculated by WC, BMI, and WHR. Results. A total of 97 subjects with T2D (36.1% female, mean age 61.7 +/- 12.0 years, BMI 26.4 +/- 3.7 kg/m 2 , A1C 6.9 +/- 1.2%) were studied. The TyG index showed a positive association with HOMA-IR, while eGDR exhibited a negative association. TyG index had the strongest correlation with IR (r = 0.49), while various eGDR formulas showed weaker negative correlations (r = 0.12-0.25). However, subgroup analysis in individuals with T2D and coronary artery disease (CAD) showed that only eGDR-WC and eGDR-BMI demonstrated a significant correlation with triple vessel disease. Conclusion. The TyG index was a useful and simple marker for identifying the presence of IR in Thai people with T2D. Future longitudinal studies are warranted to demonstrate the prediction value of cardiovascular outcomes.