OBJECTIVE: This study aimed to explore the potential correlation between the triglyceride-glucose (TyG) index and diabetic nephropathy (DN) and diabetic retinopathy (DR) in patients with early-onset type 2 diabetes mellitus (T2DM). DESIGN: This cross-sectional study statistically analysed TyG index levels across DN and DR stages in patients with early-onset and non-early-onset T2DM. PATIENTS: A total of 1530 T2DM patients were enrolled between January 2017 and August 2023 at Tianjin Fourth Central Hospital in Tianjin. MEASUREMENTS: Correlation analysis and logistic regression were used to examine the association between the TyG index and microvascular complications. Kaplan-Meier plots and Cox regression analyses were employed to evaluate the effects of the TyG index on DN incidence. TyG index's diagnostic ability for DN was explored using the area under the receiver operating characteristic curve. RESULTS: In patients with early-onset T2DM, the TyG index gradually decreased with DR aggravation and gradually increased with DN aggravation, showing a negative correlation with DR and a positive correlation with DN in patients with early-onset T2DM
logistic regression analysis suggested that the TyG index was an independent risk factor for DN (OR = 1.623, 95% CI = 1.175-2.242). The Cox regression analysis and Kaplan-Meier plots suggested that higher TyG was associated with an earlier incidence of DN in patients with early-onset T2DM. CONCLUSION: In patients with early-onset T2DM, the TyG index could be used to evaluate the risk of microvascular complications, with elevated TyG levels potentially indicating high risk of insulin- resistance related renal injury.