Title : Association between the triglyceride glucose Chinese visceral adiposity index and new-onset cardiovascular disease in middle-aged and older adults: Insights from the China health and retirement

Background: Insulin resistance (IR) and visceral adiposity are key pathophysiological drivers of cardiovascular disease (CVD). The triglyceride?glucose (TyG) index is a validated surrogate marker for IR, and the Chinese visceral adiposity index (CVAI) specifically reflects visceral fat accumulation in Chinese populations. However, the combined index TyG?CVAI (TyG × CVAI) has not been fully evaluated for its association with new?onset CVD in the general population, especially regarding potential nonlinear relationships and threshold effects.

Methods:This prospective cohort study used data from the China Health and Retirement Longitudinal Study (CHARLS). Participants aged ≥45 years without baseline CVD were included. The TyG?CVAI was calculated and divided into quartiles. The primary outcome was new?onset CVD (self?reported physician?diagnosed heart disease or stroke) during follow?up (2011–2020). Kaplan?Meier curves, multivariable Cox proportional hazards models, restricted cubic splines (RCS), and two?piecewise linear regression were used to assess associations and nonlinearity. Receiver operating characteristic (ROC) curves compared predictive performance of TyG?CVAI, TyG, and CVAI.

Results:Among 7,977 participants (median age 58 years, 52.5% female), 1,221 developed CVD during the 9?year follow?up. The cumulative incidence increased progressively across TyG?CVAI quartiles (Q1: 11.11%, Q4: 20.66%; log?rank P<0.001). In the fully adjusted model (demographics, lifestyle, and cardiometabolic factors), participants in the highest quartile (Q4) had a 64% higher risk of CVD compared with the lowest quartile (HR=1.64, 95% CI 1.35–2.00; P<0.001). RCS analysis revealed a significant nonlinear relationship (P for nonlinearity <0.05). Two?piecewise regression identified a clear threshold at TyG?CVAI = 778.62. Below this value, no significant association was observed (HR=0.95, 95% CI 0.83–1.08; P=0.821); above it, each unit increase in TyG?CVAI was associated with a 47% higher CVD risk (HR=1.47, 95% CI 1.31–1.64; P<0.001). The TyG?CVAI showed superior predictive performance (AUC=0.6315) compared with TyG alone (0.5938) and CVAI alone (0.5851). Subgroup and sensitivity analyses confirmed the robustness of these findings across different strata and after excluding participants with hypertension, dyslipidaemia, or diabetes.

Conclusions:A higher baseline TyG?CVAI is independently and nonlinearly associated with an increased risk of new?onset CVD in middle?aged and older Chinese adults, with a distinct risk threshold. The TyG?CVAI outperforms its individual components (TyG and CVAI) in predicting CVD. This simple, low?cost integrated biomarker combining IR and visceral adiposity may serve as a practical tool for early risk stratification and primary prevention of CVD, particularly in resource?limited settings.

Dr. Wenling Zheng earned her Ph.D. from Xi'an Jiaotong University. She is a geriatric cardiology specialist with a strong focus on cardiovascular risk factors, insulin resistance, and visceral adiposity in aging populations. She has published multiple high-impact SCI papers in the field of cardiovascular disease. Dr. Zheng currently works at the First Affiliated Hospital of Xi'an Jiaotong University, where she integrates clinical practice with longitudinal cohort research to improve early risk stratification and prevention strategies for older adults.