Associations of cumulative exposure and two-time-point clustering of the triglyceride-cholesterol-body weight index with incident cardiovascular disease in middle-aged and older Chinese adults: a nationwide cohort study

AIMS: The triglyceride-cholesterol-body weight index (TCBI) has been proposed as a biomarker of the prognosis of stroke. However, the relationship between cumulative exposure and dynamic trajectories of the TCBI (cuTCBI/TCBI changes) and the risk of cardiovascular disease (CVD) remains unclear. The aim of this study is to examine the association between cuTCBI/TCBI changes and the risk of CVD. METHODS AND RESULTS: The participants were from the China Health and Retirement Longitudinal Study (CHARLS). Partitioning Around Medoids (PAM) algorithm, Cox regression model, restricted cubic spline (RCS), Kaplan-Meier analysis and subgroup analysis were employed to evaluate the association between cuTCBI/TCBI changes and CVD risk. In model 3, compared to Q1, the risk of CVD increased by 83% for Q4 (HR:1.83, 95%CI: 1.49,2.24) (P for trend < 0.001). RCS analysis revealed a significant nonlinear relationship between cuTCBI and CVD risk. The results of PAM clustering demonstrated that the participants in moderate increase cluster (HR:1.35, 95%CI: 1.17,1.56, P < 0.001) and persistently high level cluster (HR:1.49, 95%CI: 1.22,1.83, P < 0.001) demonstrated a significantly elevated risk of CVD compared with the stable low risk cluster, with a significant trend towards increased risk across clusters (P for trend < 0.001). In the gender-stratified analysis, significant associations were observed in males, whereas the female TCBI change clusters did not reach statistical significance in the fully adjusted model. CONCLUSION: Our research demonstrated a significant association between cuTCBI/TCBI changes and the increased risk of CVD. And the relationship between cuTCBI and CVD risk is nonlinear. The association between TCBI change clusters and outcomes may differ by gender, with statistical significance observed only in males. Our results indicated that regular monitoring of cuTCBI levels and maintaining relatively low levels may be crucial for CVD prevention.