Association of triglyceride-glucose index and vascular aging with cardiovascular diseases in China: PURE cohort study

Abstract Introduction Evidence showed that impaired fasting glucose and arterial stiffness were relevant, however, the association between the Triglyceride-Glucose (TyG) index and vascular aging, and their effects on CVD events, warrants further exploration. Purpose We aimed to explore the association between vascular aging and incident CVD events, and to assess whether IR interacts with or exerts a joint effect on vascular aging in relation to mortality and CVD outcomes. Methods Our study used data based on Prospective Urban Rural Epidemiology China (PURE-China), a large prospective cohort study of 47,931 individuals aged 35-70 years from 12 provinces in China. Vascular aging was categorized into supernormal (SVA), healthy (HVA), and early vascular aging (EVA) based on estimated pulse wave velocity (ePWV). The TyG index, calculated from TG and FBG, served as an IR surrogate. Multivariable Cox frailty models assessed associations between vascular aging and CVD risk. Interaction and joint effect analyses were conducted to examine IR's role between vascular aging and outcomes. Results A total of 40,513 participants with complete information were included in the current study. During a median follow-up of 11.9 years (IQR 9.5-12.5), we recorded 3,615 major CVD events, 2,344 all-cause mortality, 829 CVD death, and 3,505 non-fatal CVD. After adjusting for all other variables, CVD risks increased with worsening baseline vascular aging status. Compared to HVA, the EVA was associated with higher incidence of major CVD (HR 2.15; 95% CI 1.98-2.34), all-cause mortality (HR 2.86; 95% CI 2.59-3.16), CVD death (HR 4.01; 95% CI 3.42-4.70), and non-fatal CVD (HR 1.62; 95% CI 1.48-1.77). Conversely, SVA was associated with lower incidence of the major CVD (HR 0.33; 95% CI 0.26-0.41), all-cause mortality (HR 0.38; 95% CI 0.29-0.49), CVD death (HR 0.40; 95% CI 0.24-0.66), and non-fatal CVD (HR 0.36; 95% CI 0.29-0.45). Furthermore, in EVA, the highest TyG quartile jointly increased major CVD incidence (OR 1.335; 95% CI 1.026–1.737). In HVA, the third TyG quartile jointly reduced CVD death incidence (OR 0.686; 95% CI 0.485–0.970). While no significant interaction effect of the TyG index was observed. Conclusion IR, as measured by the TyG index, influences the association between vascular aging and CVD incidence. These results may inform recommendations on targeted interventions for vascular aging and IR, thereby advancing primary prevention and risk management of chronic disease.