Comparative Prognostic Value of SHR, TYG, and CHG for Predicting In-Hospital Cardiac Arrest in Critically ill Patients: A Dual-Center Cohort Study

Purpose In-hospital cardiac arrest (IHCA) is a high-mortality event requiring better early risk stratification. This study aimed to investigate the association between three accessible insulin resistance (IR) markers—the Stress Hyperglycemia Ratio (SHR), Triglyceride-Glucose Index (TYG), and Cholesterol, High-Density Lipoprotein, and Glucose index (CHG)—and the risk of IHCA in critically ill patients. Patients and Methods: This dual-center retrospective cohort study included adult patients from the MIMIC-IV (development) and NWICU (validation) databases. The associations between admission levels of SHR, TYG, and CHG and the primary outcome of IHCA, along with secondary outcomes (acute kidney injury [AKI] and sepsis), were assessed using multivariable logistic regression. We further explored dose-response relationships with restricted cubic splines (RCS) and threshold effect analysis. The robustness of findings was tested via subgroup analyses, and potential mechanisms were explored using mediation analysis. Predictive performance was compared using receiver operating characteristic (ROC) curves. Results A total of 3,059 patients from MIMIC-IV and 1,849 from NWICU were included. In the MIMIC-IV cohort, after full multivariable adjustment, elevated levels of SHR (OR 2.888, 95% CI 1.883–4.427), TYG (OR 1.446, 95% CI 1.075–1.946), and CHG (OR 1.580, 95% CI 1.050–2.378) were all independently associated with an increased risk of IHCA ( P  < 0.05). Restricted cubic splines revealed a significant non-linear, dose-response relationship between SHR and IHCA ( P for non-linearity = 0.007), whereas the associations for TYG and CHG were linear ( P for non-linearity > 0.05). Mediation analysis indicated that the white blood cell (WBC) partially mediated these associations, accounting for 11.3%, 12.1%, and 14.5% of the total effect for SHR, TYG, and CHG, respectively. These findings, including significant associations with the secondary outcomes of AKI and sepsis, were successfully validated in the NWICU cohort. In predictive performance for IHCA, ROC analysis confirmed that SHR had the superior discriminatory ability (AUC = 0.763), outperforming both TYG (AUC = 0.624) and CHG (AUC = 0.639). Conclusion Elevated admission levels of SHR, TYG, and CHG are independent predictors of IHCA and other adverse outcomes in a broad population of critically ill patients. Among them, SHR demonstrated the strongest predictive ability. These readily available and inexpensive markers may serve as valuable tools for early bedside risk stratification to identify patients at high risk for circulatory collapse.