Triglyceride glucose index as a surrogate marker of insulin resistance and its correlation with serum leptin levels in gestational diabetes

Abstract

Background: Gestational diabetes mellitus (GDM) is a leading global public health burden affecting up to 12.8% of women. Hyperinsulinemia stimulates adiposity and leptin production. Triglyceride glucose index (TyG) is gaining much acceptance as an indicator of insulin resistance. Very little data are available in the literature regarding the association between insulin resistance and serum leptin concentration in GDM. Aims and Objectives: The aims of this study were as follows: (1) To find the correlation between TyG index as a marker of insulin resistance and serum leptin levels in GDM. (2) To determine the role of leptin in predicting large for gestational age (LGA) births. Materials and Methods: In this analytical cross-sectional study, fasting blood samples were taken from 200 GDM women and 200 healthy controls and analyzed for blood glucose, serum triglycerides, and leptin levels. Quantitative leptin assay was done by Sandwich type enzyme immunoassay. TyG index was defined as Ln (fasting triglycerides [mg/dL] × fasting blood glucose [mg/dL]/2). Results: The mean TyG index and leptin levels were higher in GDM group. There was a weak positive correlation between TyG index and leptin levels which were not statistically significant. Multiple logistic regression analysis showed association between third trimester maternal serum leptin levels and LGA births. Conclusion: TyG index and leptin levels were elevated in gestational diabetes. Increased maternal leptin levels could increase the risk of LGA births. Further, research is needed to better understand the role of leptin throughout pregnancy and its influence on fetal growth.