Association between changes in the cardiometabolic index and new-onset cardiovascular diseases in middle-aged and elderly individuals: findings from the China Health and Retirement Longitudinal Study

Objectives Cardiometabolic index (CMI) is a new obesity and lipid metabolism-related index consisting of anthropometric and biochemical index. Our study aimed to examine the association between CMI control level and cardiovascular diseases (CVD) risk in middle-aged and elderly individuals. Methods A total of 4,239 subjects were enrolled from the China Health and Retirement Longitudinal Study (CHARLS). The K-means clustering model and cumulative CMI to assess change in the CMI from 2012 to 2015. The association between CMI change and new-onset CVD was evaluated using Cox regression models and restricted cubic splines (RCS). Subgroup analyses and interaction tests were conducted to evaluate potential relationships between changes in CMI and outcomes across different subgroups. Results There were 872 subjects eventually developed CVD, including 652 cases of heart disease and 352 cases of stroke. New-onset CVD was positively and independently correlated with changes in CMI. Subjects with consistently high CMI had a higher new-onset CVD risk. The higher cumulative CMI was associated with a stepwise increase in outcomes. RCS showed the correlation between cumulative CMI and outcomes was nonlinear. Conclusion Sustained high CMI was related to an elevated risk of new-onset CVD in middle-aged and elderly population. Continuous CMI monitoring significantly enhances the accuracy of new-onset CVD risk stratification, potentially lowering CVD incidence.