Cost-Effective Markers for Identifying Poor Glycemic Control in Type 2 Diabetes Mellitus: The Role of the Triglyceride-Glucose Index.

Background Insulin resistance is a major risk factor for type 2 diabetes mellitus (T2DM), contributing to poor glycemic control and diabetic complications. This study aimed to investigate the correlation of the triglyceride-glucose (TyG) index, TyG-BMI index, and TG/HDL ratio with glycemic control. Methods A cross-sectional study was conducted from October 2023 to February 2024 at the Jericho Health Center, Palestine. A total of 240 T2DM patients were categorized into two groups based on glycemic control: good (HbA1c <7) and poor (HbA1c ≥7). Spearman correlation was used to assess the associations, and receiver operating characteristic (ROC) curve analysis was used to evaluate the predictive performance of the indices. Results Of 240 patients, 39% had good and 61% had poor glycemic control. The TyG and TyG-BMI indices were significantly higher (P<0.001) in those with poor glycemic control (5.0 vs. 4.8; 155 vs. 142, respectively). The TyG index cutoff was 4.8 (81% sensitivity, 55% specificity; AUC=0.744, p<0.001) while the TyG-BMI index cutoff was 162 (43.2% sensitivity, 76.3% specificity; AUC=0.591, p=0.018). The TyG index correlated positively with fasting plasma glucose (r=0.687), HbA1c (r=0.464), triglycerides (r=0.740), and cholesterol (r=0.254), and negatively with HDL-C (r=-0.200; all p<0.01). TyG-BMI correlated strongly with BMI (r=0.939) and weakly but significantly with systolic (r=0.204) and diastolic blood pressure (r=0.146). No significant correlation was found between TG/HDL and glycemic control. Conclusion Compared to TyG-BMI, the TyG index showed better diagnostic accuracy and stronger associations with metabolic markers, suggesting it may serve as a cost-effective and practical marker for evaluating glycemic control in T2DM patients. The low area under the curve (AUC) and sensitivity of TyG-BMI might limit its usefulness in this context. Establishing a population-specific cutoff based on inexpensive and routine laboratory measures enhances its practical utility in clinical settings.