The Correlation between TyG Index and Islet Function Evaluation Index in Obese People

LI Jing; QU Pengxia; LIU Yuenan; YANG Shuang; LI Yuanbin

doi:10.12102/j.issn.1672-1349.2025.23.020

Abstract：Objective: To observe the changes in triglyceride-glucose (TyG) index and insulin resistance index (HOMA-IR) in different obese populations, explore the relationship between TyG index, HOMA-IR, blood pressure, lipid profiles, and other biochemical indicators, and analyze the correlation between TyG index and HOMA-IR as well as beta-cell insulin secretion index (HOMA-β). Methods: A total of 61 obese individuals (obese group) and 62 healthy individuals (control group) who underwent oral glucose tolerance test (OGTT) at Peking University First Hospital Taiyuan Hospital from July to December 2022 were selected. Body mass index (BMI), blood pressure, lipid profiles, blood glucose, and insulin levels were collected. TyG index, HOMA-IR, and HOMA-β were calculated. According to OGTT results, the obese population was divided into three groups: simple obesity group (NGR group), impaired glucose regulation with obesity group (IGR group), and type 2 diabetes mellitus with obesity group (T2DM group). Pearson or Spearman correlation analysis was used to analyze the correlations between variables. TyG index was set as the independent variable, while HOMA-IR and HOMA-β were set as dependent variables for multiple linear regression analysis. Results: Systolic blood pressure, diastolic blood pressure, systemic inflammatory index (SII), uric acid (UA), low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), triglycerides (TG), fasting plasma glucose (FPG), and TyG index were significantly higher in the obese group compared to the control group. TG, TyG index, glycated hemoglobin (HbA1c), and HOMA-IR were significantly higher in the T2DM group than in the NGR and IGR groups, while HOMA-β was significantly lower, with all differences being statistically significant (P < 0.05). TyG index showed a positive correlation with age, BMI, blood pressure, UA, TC, LDL-C, HOMA-IR, and HbA1c (P < 0.05), and a negative correlation with HOMA-β and high-density lipoprotein cholesterol (HDL-C) (P < 0.05). HOMA-IR showed a positive correlation with BMI, waist circumference, hip circumference, alanine aminotransferase (ALT), aspartate aminotransferase (AST), UA, TG, LDL-C, TyG index, and HbA1c (P < 0.05), and a negative correlation with HDL-C (P < 0.05). Multivariate linear regression analysis showed that after adjusting for multiple confounding factors, as TyG index increased, HOMA-IR gradually increased, and HOMA-β gradually decreased. Conclusion: After adjusting for confounding factors, as TyG index increased, insulin resistance in obese populations became more severe, and pancreatic beta-cell function was more impaired. TyG index can reflect HOMA-IR to some extent, and can be used as an initial screening indicator for assessing insulin resistance in obese populations in clinical practice.