1991-LB: Triglyceride–Glucose Index Is an Effective Tool for Assessing Glycemic Control in Asian Indians with Type 2 Diabetes

Introduction & Objective: Glycated hemoglobin (HbA1c) may not accurately reflect glycemic control in certain conditions like hemoglobinopathy, hemolytic anemia, or acute blood loss. There is a need for alternative tools for assessing glycemic control, particularly in India, where high costs and unavailability of standardized assays make widespread use of HbA1c challenging. We attempted to evaluate the efficacy of the Triglyceride-glucose (TyG) index, as a cost-effective alternative to HbA1c for assessment of glycemic control.

Methods: Cross-sectional data from the South Asia Biobank were analyzed. This included data of 8597 adults (aged ≥18 years) with type 2 diabetes (T2D) from Chennai and Delhi, India, surveyed during the period 2019-21. T2D was diagnosed if the fasting plasma glucose [FPG] ≥126 mg/dl and/or HbA1c ≥6.5%. TyG index was calculated using the formula Ln [fasting triglycerides (mg/dL) × FPG (mg/dL)/2]. Receiver Operating Curve (ROC) and multivariable logistic regression were used to quantify the association of TyG index with HbA1c.

Results: TyG index (Mean± SD: 5.1±0.3 vs.4.8±0.3, p<0.001) was significantly higher in those with suboptimal glycemic control (HbA1c ≥7%) compared to those with good control (HbA1c <7%), and showed significant correlation with HbA1c (r=0.501; p<0.001). After adjusting for age and sex, regression analysis showed that Tertile 2-TyG index ≥4.9-5.6 (Odds Ratio [OR] 2.7, 95% Confidence Interval [CI]: 2.5-3.1) and Tertile 3-TyG index ≥5.7 (OR 9.1, 95% CI:8.0-10.3) were associated with HbA1c ≥7%. The area under the curve (AUC) of the ROC curve of TyG index ≥5.03 for prediction of HbA1c ≥7% was 0.75 (95% CI,0.74-0.76) with a sensitivity of 63% and specificity of 74% (p<0.001).

Conclusion: The TyG index appears to be a cost-effective marker for assessing glycemic control, offering a valuable tool for monitoring diabetes in low-resource settings and situations where HbA1c cannot be reliably estimated.