Stress hyperglycemia ratio as a predictor of in-hospital mortality in patients with acute kidney injury: a retrospective cohort study.

objectiveTo investigate the relationship between the stress hyperglycemia ratio (SHR) and the risk of in-hospital mortality in patients with acute kidney injury (AKI), and to evaluate its predictive performance.

methodsA retrospective cohort study used the Medical Information Mart for Intensive Care (MIMIC-IV) and MIMIC-III databases. SHR was defined as the ratio of admission blood glucose to estimated average glucose. Restricted cubic spline regression analyzed the nonlinear relationship between SHR and in-hospital mortality. Multivariate logistic regression and subgroup analyses were applied to validate the robustness of the association. Receiver operating characteristic (ROC) curve analysis was employed to evaluate the predictive performance of SHR.

resultsAmong 2180 patients, in-hospital mortality was 18.8% (263/1,398) in MIMIC-IV and 19.8% (155/782) in MIMIC-III. SHR showed a U-shaped relationship with in-hospital mortality, where SHR > 1.19 or < 0.50 significantly increased death risk (P < 0.05). The overall pattern was consistent across subgroup and sensitivity analyses. ROC curve analysis demonstrated that SHR had better predictive performance than conventional severity and comorbidity scores for hospital mortality in AKI patients. The highly consistent results from both databases indicate reliability.

conclusionSHR is an independent predictor of in-hospital mortality in AKI patients. By distinguishing the extreme low-SHR range from the intermediate lowest-risk range, this study further characterized the bidirectional nonlinear risk pattern, facilitating early identification of high-risk patients for risk stratification.