The potential of Insulin Resistance Indices to predict Non-alcoholic Fatty Liver Disease in Patients with Type 2 Diabetes

Abstract Background: The triglyceride-glucose (TyG) index and related parameters, and as well as Homeostatic Model Assessment for Insulin Resistance(HOMA-IR), are recently developed as insulin resistance markers, which can identify the individuals with a risk of non-alcoholic fatty liver disease (NAFLD). However, whether it can be used to predict NAFLD among patients with type 2 diabetes mellitus (T2DM) remains unclear. This study aims to observe the performance of insulin resistance indices in diagnosing NAFLD combined with T2DM, and compare the diagnostic values in clinical practice. Patients and Methods: 268 patients with T2DM from the Endocrinology Department of Jiangsu Provincial Hospital of Traditional Chinese Medicine were enrolled in this study, they were divided into two groups: the NAFLD group (T2DM with NAFLD) and the T2DM group (T2DM without NAFLD). General information and blood indicators of the pariticipants were collected, and insulin resistance indices were calculated based on the data. Furthermore, receiver operating characteristic (ROC) analysis was conducted to calculate the area under the curve (AUC) of the insulin resistance-related indices. Results：ROC analysis revealed that among the five insulin resistance-related indices, four parameters (TyG、TyG-BMI、TyG-WC and TyG-WHR) exhibit high predictive performance for identifying NAFLD except for HOMA-IR. Of particular, TyG-BMI demonstrated the superior predictive value, especially in the males and individuals with a BMI less than 23 kg/m². For the male and the lean patients, AUC for TyG-BMI was 0.764 (95% CI 0.691 - 0.827) and 0.817 (95% CI 0.626 - 0.937), respectively. The sensitivity and specificity for the male NAFLD were 90.32% and 47.89%. While for the lean patients, the sensitivity and specificity were 80% and 82.6%, respectively. Moreover, In the fully adjusted models, there were positive associations of TyG, TyG-BMI, TyG-WC, TyG-WHR and HOMA-IR to CAP, with the βs of 21.30, 0.745, 0.247 and 2.549 (all p<0.001), respectively. Conclusion: TyG-BMI is promising to predict NAFLD combined with T2DM, especially for the lean and male T2DM patients.