Insulin resistance, vulnerable plaque and stroke risk in patients with carotid artery stenosis

Insulin resistance (IR) is linked to both the vulnerable plaque and the stroke risk. However, the precise extent of this correlation and its impact on stroke risk in carotid artery stenosis patients remain unclear. Therefore, this study aims to investigate the relationship between vulnerable plaque and IR and stroke risk and the mediating role of vulnerable plaque in patients with carotid artery stenosis. This study included 505 patients with carotid artery stenosis. IR was assessed using the triglyceride-glucose (TyG) index. The association of the TyG index and vulnerable plaque with stroke risk was investigated using the restricted cubic splines (RCS)and adjusted Logistic regression. Additionally, the mediation analysis was used to explore the mediating impact of the vulnerable plaque on the association between the TyG index and stroke risk. A total of 184 (36.4%) stroke events were recorded. The RCS curves revealed a positive linear association between TyG index and risk events among patients with carotid artery stenosis (P-value < 0.001 and P for nonlinear = 0.860). After fully adjusting for covariates, both the TyG index and vulnerable plaque emerged as significant predictors of stroke events. Mediation analysis indicated that the vulnerable plaque mediated 18.3%, 15.8%, 13.9%, and 11.6% of the correlation between the TyG index and stroke risk in different adjusted models, respectively. TyG index and vulnerable plaque are associated with a higher risk of stroke in patients with carotid artery stenosis. In addition, vulnerable plaques partially mediated the relationship between TyG index and stroke risk.