Association between cardiometabolic index and stage progression in cardiovascular–kidney–metabolic syndrome: insights from a Chinese population-based cohort study

BACKGROUND: The emerging concept of cardiovascular-kidney-metabolic syndrome (CKM) highlights the pathophysiological interconnection between cardiorenal and metabolic disorders. This study investigates the longitudinal association between the cardiometabolic index (CMI) and CKM stage progression. METHODS AND RESULTS: This study utilized data from the China Health and Retirement Longitudinal Study. The baseline CMI was computed utilizing the triglycerides-to-high-density lipoprotein cholesterol ratio multiplied by the waist-to-height ratio. CKM is defined and categorized into five stages (0-4) based on metabolic, cardiovascular, and renal disorders. We evaluated the impact of CMI on the CKM stage progression from Wave 1(2011) to Wave 3(2015). Multivariable logistic regression and restricted cubic spline (RCS) models were constructed to illustrate the relationship between CMI and CKM stage progression. A total of 4080 patients were included. The rate of CKM progression to advanced stages significantly increased with higher CMI quartiles. When entered into the multivariable logistic regressions as a continuous variable, elevated CMI was a remarkable predictor for progression to CKM stages 2-4 among participants at baseline CKM stages 0-1 [OR(95%CI) 1.66 (1.32-2.11)], progression to CKM stages 3-4 among those at baseline CKM stages 0-2 [OR(95%CI) 1.14 (1.03-1.26)], and progression to CKM stage 4 among those at baseline CKM stages 0-3 [OR(95%CI) 1.13 (1.00-1.28)], after adjustment for potential confounders. This association persisted when CMI was modeled as a categorical variable. RCS analysis demonstrated significant positive associations between elevated CMI levels and an increased risk of progression to advanced CKM stages (all P < 0.05). CONCLUSION: Elevated CMI is significantly associated with CKM stage progression over time. CMI could act as a simple, useful tool for the risk assessment of CKM.