Association of the Chinese visceral adiposity index with incident cardiovascular disease in cardiovascular-kidney-metabolic syndrome stages 0–3: a nationwide prospective cohort study

Background Cardiovascular-kidney-metabolic (CKM) syndrome integrates metabolic abnormalities, chronic kidney disease, and cardiovascular disease (CVD), with stages 0–3 representing a critical window for primary prevention. Whether the Chinese visceral adiposity index (CVAI) adds predictive value for CVD in this population remains uncertain. Methods Using data from the China Health and Retirement Longitudinal Study (CHARLS), a nationwide prospective cohort, we included 7,539 participants with CKM stages 0–3. Incident CVD (heart disease or stroke) was the primary outcome. Cox proportional hazards models and restricted cubic splines assessed the association and dose-response relationship, and discrimination was evaluated with the AUC and censoring-adjusted time-dependent AUC, with comparisons against BMI, waist circumference, VAI, and TyG. Results Over a median follow-up of 8.0 years, 1,718 incident CVD events were recorded. Each SD increase in CVAI was associated with a 19.5% higher CVD risk (HR, 1.195; 95% CI, 1.135–1.259), with a graded quartile effect (Q4 vs. Q1 HR, 1.585; 95% CI, 1.359–1.848; P for trend < 0.001) and a continuous dose-response relationship ( P for nonlinearity = 0.931). Adding CVAI modestly improved discrimination (AUC, 0.640 to 0.646; DeLong P = 0.039), but its AUC was not superior to BMI (0.647) or waist circumference (0.646). Primary CVAI findings remained consistent across subgroup and sensitivity analyses and in competing-risk models, whereas VAI showed no significant independent association. Conclusions CVAI is independently and continuously associated with incident CVD in CKM stages 0–3 and may serve as a practical adjunctive tool for early CVD risk stratification.