Relationship between the Chinese Visceral Adipose Index and Cardiovascular Disease in Postmenopausal Women: a Prospective Cohort Study

Background Cardiovascular disease (CVD) is a major threat to the health of women, particularly postmenopausal women, who are at higher risk. The reduction in estrogen levels following menopause may contribute to visceral fat accumulation, which is closely linked to insulin resistance, chronic inflammation, and lipid metabolism disorders, potentially increasing the risk of CVD. However, the relationship between Chinese visceral adipose index (CVAI) and CVD risk in this population remains insufficiently explored. Objective To explore the relationship between CVAI and CVD in postmenopausal women, and thereby provide information on the prevention of CVD in this high-risk population. Methods Based on the data of China Health and Retirement Longitudinal Study (CHARLS) from 2015 to 2020, we enrolled 4 743 postmenopausal women aged≥45 years free of CVD at baseline in 2015. The CVAI at baseline was used as the exposure, while incident CVD events during follow-up in 2018 and 2020 served as the outcome. Cox proportional hazards regression models were employed to assess the association between CVAI and CVD risk. Restricted cubic spline (RCS) analysis was further applied to evaluate potential dose-response relationships. Results At the end of the follow-up period, the incidence rates of CVD, heart disease, and stroke among the 4 743 postmenopausal women were 20.2% (958/4 743), 13.6% (645/4 743), 8.3% (393/4 743), respectively. The participants were stratified into quartiles based on their baseline CVAI levels, with the following cutoff values: Q1 (≤84.78)(n=742), Q2 (84.78, 108.49)](n=1 249), Q3 (108.49, 132.01](n=1 463), and Q4 (>132.01)(n=1 289). After adjustment for confounding factors, Cox proportional hazards regression showed that compared to the Q1 reference group, women in the CVAI Q2, Q3 and Q4 groups faced significantly elevated risks, the risk of CVD increased by 33% (HR=1.33, 95%CI=1.00-1.76) in Q2, 69% (HR=1.69, 95%CI=1.29-2.21) in Q3 and 82% (HR=1.82, 95%CI=1.38-2.14) in Q4, the risk of stroke increased by 76% (HR=1.76, 95%CI=1.10-2.82) in Q3, 95% (HR=1.95, 95%CI=1.21-3.14) in Q4, and the risk of heart disease increased by 57% (HR=1.57, 95%CI=1.14-2.15) in Q3, and 68% (HR=1.68, 95%CI=1.21-2.33) in Q4, respectively. RCS analysis confirmed dose-response relationships between CVAI and risks of CVD, heart disease, and stroke (P