AIM: The American Heart Association (AHA) introduced the Cardiovascular-Kidney-Metabolic (CKM) syndrome in 2023, emphasising low survival rates in advanced CKM patients. This study explores the predictive value of the triglyceride-glucose (TyG) index and its associated indices for all-cause and cardiovascular mortality in these patients.
METHODS: Data from 5,858 patients with advanced CKM (defined as stage 3/4 CKM per AHA criteria) were extracted from the National Health and Nutrition Examination Survey (NHANES), USA. The median follow-up duration for mortality outcomes was 8.21 years. Patients were categorised into tertiles (T) based on the TyG index and its associated indices (TyG-waist-to-height ratio [TyG-WHtR] and TyG-weight-waist index [TyG-WWI]; T1, T2, T3). Cox proportional hazards regression was used to analyse the prognostic value of these indices, adjusting for various covariates, and the results were presented as hazard ratio (HR) and 95% confidence interval (CI). Restricted cubic splines (RCS) assessed linear or nonlinear relationships between these indices and advanced CKM risk, with subgroup analyses for stratified examination.
RESULTS: A total of 5,826 and 5,150 patients were included for the analysis of all-cause mortality and cardiovascular mortality, respectively. Multivariable Cox regression demonstrated that in the T3 group, both TyG-WHtR (HR 1.33, 95% CI 1.04-1.70) and TyG-WWI (1.40, 1.01-1.95) were significantly associated with all-cause mortality. Similar associations were observed for cardiovascular mortality, with TyG-WHtR (1.47, 1.06-1.88) and TyG-WWI (1.71, 1.06-2.78) showing comparable effects. Both indices exhibited a J-shaped association with mortality, with significant increases in HRs for all-cause mortality observed at TyG-WHtR ≥5.43 and TyG-WWI ≥99.03, while cardiovascular mortality HRs showed a significant rise at TyG-WWI ≥98.87.
CONCLUSION: This study is the first known to link TyG-WHtR and TyG-WWI with all-cause and cardiovascular mortality in advanced CKM patients, indicating their significant predictive value for this population.
