Triglyceride-glucose index and the incidence of peripheral artery disease: a dose-response meta-analysis of longitudinal studies

Background The triglyceride-glucose (TyG) index is a simple surrogate marker of insulin resistance and has been increasingly investigated as a predictor of cardiovascular diseases. However, longitudinal evidence regarding its association with incident peripheral artery disease (PAD) remains limited and inconsistent. We conducted a systematic review and dose-response meta-analysis to evaluate the association between the TyG index and the risk of incident PAD. Methods PubMed, Embase, and Web of Science were systematically searched from inception to June 28, 2026. Longitudinal observational studies evaluating the association between the conventional TyG index and incidents PAD in adults were eligible. Pooled risk ratios (RRs) and 95% confidence intervals (CIs) comparing the highest versus lowest TyG categories were calculated using restricted maximum likelihood random-effects models. Linear and nonlinear dose-response meta-analyses were performed using restricted cubic spline models. Results Five longitudinal studies involving 417,499 participants and 7,800 incident PAD events were included. Compared with the lowest TyG category, a high TyG index was associated with a significantly increased risk of incident PAD (RR = 1.49, 95% CI 1.06 to 2.10; p = 0.02), although substantial heterogeneity was observed (I 2 = 88.4%). Sensitivity analyses demonstrated robust findings. In the linear dose-response meta-analysis, each 1-unit increase in the TyG index was associated with a 22% higher risk of incident PAD (RR = 1.22, 95% CI 1.08 to 1.37; p = 0.001). Restricted cubic spline analysis demonstrated a significant overall dose-response association ( p = 0.001) with no evidence of nonlinearity ( p for nonlinearity = 0.367), indicating an approximately linear relationship between the TyG index and PAD risk. Conclusions A higher TyG index is associated with an increased risk of incident PAD in a dose-dependent and approximately linear manner. Systematic Review Registration https://www.crd.york.ac.uk/PROSPERO/ , identifier CRD420261470450.