Comparison of Triglyceride-Glucose Index with HbA1c and HOMA-IR as a risk marker for prediabetes and insulin resistance in a tertiary care hospital in Chittagong

Abstract

Prediabetes is a state of intermittent hyperglycaemia which has the potential to the future development of Diabetes Mellitus and cause micro as well macrovascular complications. Triglyceride Glucose (TyG) Index is a cheaper alternative to the more expensive Homeostasis Model for Insulin Resistance (HOMA-IR) and Haemoglobin A1c (HbA1c) essays are quick, reliable and easily reproducible in everyday clinical settings. The aim of this study is to find whether TyG index is comparable to HOMA IR for insulin resistance and to HbA1c as a reliable screening tool for prediabetes. A descriptive type of observational case-control study was conducted among 100 prediabetes individuals and matched with 100 of their corresponding age and sex equivalent normoglycaemic controls in the outpatient department of Chittagong Diabetic General Hospital between October 2021 till end of September 2022. Anthropometric Measurements and Laboratory parameters like Fasting Plasma Glucose, Fasting Serum Insulin and Triglycerides, HOMA-IR, HbA1c were measured, and comparative analysis were done between Tyg Index and HbA1c and HOMA-IR with Receiver Operator Characteristics (ROC) curves and Pearson correlation analysis respectively. The Area under the curve (AUC) demonstrated a higher ROC AUC score for HbA1c (0.923) as compared to the TyG Index (0.874) for diagnosing prediabetes but the differences were not statistically significant with a p-value of 0.062 which demonstrates that TyG Index is comparable to HbA1c. The Pearson correlation coefficients between the various anthropometric measurements related to insulin resistance with TyG Index and HOMA-IR demonstrates a highly significant difference in weight (0.186 vs 01.54) in favor of TyG Index with a p-value of <0.01 and a significant difference in Body Mass Index (0.421 vs 0.372), Waist Circumference (0.286 vs 0.253) and Waist to height Ratio (0.392 vs 0.333) in favor of TyG index which stipulates that TyG is comparable and in fact a better indicator of insulin resistance and thereby metabolic dysfunction as opposed to HOMA-IR with a p-value of <0.05. TyG index is a reliable surrogate marker for IR and is also comparable to HbA1c for monitoring glycaemic status and predicting/identifying prediabetes as well. Hence, it can be used as an alternative screening tool for the better management of high-risk individuals prone to develop prediabetes