Triglyceride-glucose index correlates with all-cause mortality of patients in intensive cardiac care unit: from two large-scale cohorts

Background: The triglyceride-glucose (TyG) index is widely recognized owing to its effectiveness and practicality in evaluating insulin resistance and has been confirmed to correlate with adverse outcomes in multiple cardiovascular diseases. The current study intends to clarify the relationship between the TyG index and clinical prognoses among populations in the intensive cardiac care unit (ICCU). Methods: This multicenter, retrospective investigation leveraged records from 209 medical centers. Kaplan–Meier curves were employed to assess the cumulative incidence of mortality. The association between TyG index and prognostic outcomes in the ICCU patient cohort was evaluated using Cox and linear regression analyses, along with restricted cubic splines (RCS). Correlation analysis was conducted to examine the link of TyG with cardiovascular risk factors. To mitigate potential confounding influences, we applied propensity score matching (PSM), overlap weighting (OW), and inverse probability of treatment weighting (IPTW) methodologies. Subgroup analyses were carried out according to identified modifiers. Results: Totally, 4508 individuals admitted to the ICCUs were ultimately enrolled. Dual in-hospital and intensive care unit (ICU) mortality exhibited gradual increases following higher TyG quartiles (all log-rank P for trend <0.001). Multivariate cox regressions revealed significant correlations of TyG with both in-hospital [adjusted hazard ratio (HR): 1.789] and ICU mortality (adjusted HR: 1.908). RCS analysis revealed linear correlations of elevated TyG with increased mortality risk. An elevated risk of mortality was evident among cohorts following PSM, OW, or IPTW adjustments with higher TyG index. Significant correlations between TyG and certain cardiovascular risk parameters were observed, while no significant correlation was found with length of stay. Subgroup analyses identified a strong link of the TyG with mortality among males, elderly individuals, and those without DM, as well as a notable trend in cardiac surgery/cardiothoracic intensive care units. Conclusions: Elevated TyG index was found to significantly correlate with increased mortality risks in patients admitted to the ICCUs, providing new perspectives on the importance of TyG in severe cardiovascular illnesses.