Association of triglyceride-glucose index combined with Chinese visceral adiposity index and cardiovascular diseases in middle-aged and older adults: a cohort study

BACKGROUND AND AIM: Cardiovascular diseases (CVDs) have become a significant public health issue, with a strong link to insulin resistance (IR). The triglyceride-glucose (TyG) index and Chinese visceral adiposity index (CVAI) are key indicators in the development of obesity and IR. The purpose of the study is to explore the combined effect of the TyG index and CVAI on the risk of CVDs in middle-aged and older adults. METHODS AND RESULTS: This cohort study was based on the China Health and Retirement Longitudinal Study (CHARLS) from 2012 to 2020, ultimately including 6871 and 3913 participants to examine baseline and follow-up association with CVDs. Participants were divided into four groups based on quartiles and into three classes based on changes in TyG-CVAI using K-means cluster analysis. Multivariable Cox regression analysis was conducted to assess the association between different TyG-CVAI groups and the risk of CVDs. The discriminatory performance was assessed by ROC curve, Net Reclassification Improvement (NRI) and Integrated Discrimination Improvement (IDI). Both high baseline TyG-CVAI levels and persistently elevated TyG-CVAI levels were significantly associated with CVDs, with HRs of 1.61 (1.35-1.93) and 1.68 (1.38-2.05). TyG-CVAI showed higher discriminatory ability for CVDs, CHD, and stroke, with AUCs of 0.594, 0.587, and 0.603. NRI and IDI analyses indicated that the addition of TyG-CVAI significantly enhanced risk reclassification for CVDs (NRI, 0.116-0.144; P < 0.001), CHD (NRI, 0.108-0.112; P < 0.001), and stroke (NRI, 0.127-0.230; P < 0.001). CONCLUSIONS: Monitoring long-term changes in TyG-CVAI may be useful for early risk stratification of CVDs among middle-aged and elderly individuals in China.