Association between the triglyceride-glucose index and all-cause mortality in critically ill patients with traumatic brain injury: analysis of two large cohorts

Background This study aimed to assess the role of the triglyceride-glucose (TyG) index in predicting all-cause mortality in critically ill patients with traumatic brain injury (TBI). Methods This was a retrospective observational cohort study, and data were obtained from the Medical Information Mart for Intensive Care-IV (MIMIC-IV) and the eICU Collaborative Research Database (eICU-CRD). The participants were divided into three groups according to the TyG index tertiles. The primary outcome was hospital all-cause mortality. Multivariate logistic proportional regression analysis and restricted cubic spline regression were used to evaluate the association between the TyG index and hospital mortality in patients with TBI. Results A total of 865 critically ill patients with TBI were enrolled. The hospital mortality rate and intensive care unit (ICU) mortality rates were 13.4% and 8.4%, respectively. Multivariate logistic regression analysis showed that the TyG index was independently associated with an elevated risk of hospital mortality [OR 1.69 (95% CI 1.23–2.31); P = 0.001] and ICU mortality [OR 1.71 (95% CI 1.18–2.48); P = 0.004]. The restricted cubic spline regression model revealed that the risks of hospital and ICU mortality increased linearly with increasing TyG index. Conclusion The TyG index is significantly associated with hospital and ICU all-cause mortality rate in critically ill patients with TBI. This finding illustrates that the TyG index may serve as a valuable tool for identifying patients with TBI who are at an elevated risk of all-cause mortality.