Association between the cardiometabolic index and all-cause and cardiovascular mortality in diabetes and prediabetes.

BACKGROUND

The association between the cardiometabolic index (CMI) and mortality in individuals with diabetes or prediabetes remains unclear. This study sought to explore the association between the baseline CMI and all-cause mortality and cardiovascular disease (CVD) mortality in United States (U.S.) adults with diabetes or prediabetes.

METHODS

This cohort study examined the data of 17,992 individuals, aged 18 years and older, with diabetes and prediabetes, who had participated in the National Health and Nutrition Examination Survey (NHANES; 2003-2018). Kaplan-Meier curve, Cox proportional hazards model, and restricted cubic spline (RCS) curve analyses were conducted to explore the relationship between the CMI and all-cause mortality and CVD mortality. Subgroup and sensitivity analyses were conducted to check the robustness of the main findings.

RESULTS

During 137,687 person-years of follow-up (median: 7.4 years), a total of 2,718 all-cause deaths and 891 CVD-related deaths were recorded. In the multivariate adjusted models, the CMI was positively associated with the risk of all-cause mortality and CVD mortality. Specifically, the hazard ratio (HR) estimates for all-cause death and 95% confidence intervals (CIs) for the low to high CMI quartiles were 1.00 (reference), 1.056 (0.875-1.274), 1.156 (0.912-1.464), and 1.42 (1.080-1.867), respectively. While the CVD mortality HRs were 1.00 (reference), 1.041 (0.768-1.41), 1.077 (0.771-1.503), and 1.29 (0.836-1.99), respectively. The RCS analysis showed that the baseline CMI was approximately U-shaped in relation to all-cause mortality (P<0.001) and CVD mortality (P=0.03) in the participants with diabetes and prediabetes. The subgroup analysis revealed a clear interaction between the CMI and all-cause mortality based on age and sex (P=0.01 and P=0.003, respectively). It also revealed a significant interaction between the CMI and CVD mortality based on smoking status and diabetes status (P=0.02 and P=0.01, respectively).

CONCLUSIONS

The CMI demonstrated predictive value for the risk of all-cause mortality and CVD mortality among U.S. participants with prediabetes and diabetes. The relationship between the CMI and long-term mortality exhibited an approximately U-shaped pattern, highlighting its potential as a robust indicator for mortality risk stratification in this population.