Interaction and combined effect of triglyceride-glucose index and hypertension on type 2 diabetes individuals' peripheral arterial disease risk.

Background: The interaction and combined effect of the triglyceride-glucose (TyG) index, an alternative parameter of insulin resistance, along with hypertension (HT), on the risk of peripheral arterial disease (PAD), a specific type of atherosclerotic cardiovascular disease, in individuals with type 2 diabetes (T2D) seems straightforward. However, specific research on this topic remains scarce.

Methods: In this cross-sectional study, 2027 adult participants with T2D were devided into four groups based on the mean values of TyG index and various blood pressure parameters along with its category. Binary logistic regression, interaction analysis, combined effect size, and goodness-of-fit of the constructed models were performed.

Results: The TyG index's individual effect and it's combined effect with HT, or higher systolic blood pressure (SBP) or higher mean arterial pressure in patients with T2D correlated with a higher PAD risk respectively (odds ratio [OR], 0.50, [95% confidence interval {CI} 0.28-0.89]; OR, 0.32, [95% CI 0.12-0.90]; OR, 0.35, [95% CI 0.13-0.94]; OR, 0.35, [95% CI 0.12-0.98], respectively). Only an interaction effect exists between the TyG index and SBP (multiplicative interaction{INT_M}: 1.02 [1.002, 1.038]). Combining them can significantly improve the accuracy of predicting PAD (area under the receiver operating characteristic curve {AUC}_MAX = 0.7, AUC_{Model3 + TyG index + SBP}-AUC_Model3 = 0.027). All P values were < 0.05.

Conclusion: This study suggested that TyG index and hypertension, as well as their combined and interaction effect were significantly correlated with the risk of PAD in T2D individuals.