Association of cardiovascular-kidney-metabolic syndrome and all-cause mortality: a national cohort study in China.

BACKGROUND AND AIMS: The Cardiovascular-Kidney-Metabolic (CKM) syndrome proposed by the American Heart Association (AHA) has been validated for mortality risk stratification in limited populations, but large-scale longitudinal evidence from mainland China remains scarce. This study aimed to fill this gap by evaluating the association between CKM stages and all-cause mortality in middle-aged and older Chinese adults.

METHODS AND

RESULTS

We used data from the China Health and Retirement Longitudinal Study (CHARLS) spanning 2011-2020. Kaplan-Meier curves were generated, and propensity score overlap weighting was employed to balance the potential confounders. Multivariable Cox proportional hazards models were employed to examine the association of CKM stages with all-cause mortality. Restricted cubic splines (RCS) were used to explore potential nonlinear associations. Among 9223 participants (median age 58 years, 47.5% male), the prevalence of CKM stages 0-4 was 7.5%, 15.4%, 43.5%, 22.5%, and 11.0%, respectively. Over a median follow-up of 9 years, 1203 all-cause deaths were recorded. Participants in the lower CKM stages achieved relatively longer survival according to the Kaplan-Meier curves. After stratification by age and sex, compared to stage 0, stages 3 and 4 were significantly associated with increased all-cause mortality (stage 3: Hazard Ratio (HR) 1.77, 95% Confidence Interval (CI) 1.28-2.45, p < 0.001; stage 4: HR 1.46, 95% CI 1.01-2.11, p = 0.042). RCS analysis showed a nonlinear correlation between CKM stages and all-cause mortality (p-nonlinear = 0.512).

CONCLUSION

Advanced CKM stages (3-4) were associated with increased all-cause mortality risk among middle-aged and older adults in China, with a significant linear dose-response relationship.