Deciphering the Association of Fasting Blood Glucose With Gamma-Glutamyl Transferase and Uric Acid: A cross-sectional study in a tertiary care hospital in South India.

Abstract

Objectives: Fasting hyperglycaemia (FHG) in insulin resistance is due to oxidative stress wherein gamma-glutamyl transferase (GGT) and uric acid (UA) are known to impair insulin secretion from pancreatic beta cells due to their pro-oxidant action and their role in metabolism of antioxidant glutathione. This study aims to determine the association of GGT and UA with FHG and its role in predicting the onset of prediabetes.

Methods: This cross-sectional study was conducted in Government Villupuram Medical College, Villupuram, India, from July to December 2023. Individuals in the age range of 25-65 years attending the master health check-up clinic were included. The subjects were classified as normoglycaemic (FBG <100 mg/dL) or hyperglycaemic (FBG ≥100 mg/dL). GGT, UA, glucose (Glu):GGT ratio, Glu:UA ratio, lipid profile and GGT: high-density lipoprotein (HDL) were compared between the two groups using Student's t test. The parameters were compared between the quintiles of glucose using ANOVA. Pearson's correlation was used to analyse the correlation between the study parameters.

Results: A total of 500 adults were included in this study. Triglyceride (TG), TG:HDL ratio, GGT, UA and Glu:GGT, Glu:UA and GGT:HDL ratios were significantly high in fifth quintile compared to other glucose quintiles. Glu:UA and Glu:GGT ratios showed significant positive correlation with glucose levels. Receiver operating characteristic analysis showed that Glu:UA ratio was a good predictor of FHG (AUC = 0.808; P <0.0001) with a sensitivity of 70.1% and specificity of 79.8% at a cut-off value of 26.5 to diagnose insulin resistance.

Conclusion: Glu:UA and Glu:GGT ratios are surrogate markers of underlying oxidative stress and insulin resistance and good predictors of fasting hyperglycaemia.