The association between stress hyperglycemia ratio and clinical outcomes in patients with sepsis-associated acute kidney injury: a secondary analysis of the MIMIC-IV database

Background The stress hyperglycemia ratio (SHR) is associated with poor outcomes in critically ill patients. However, the relationship between SHR and mortality in patients with sepsis-associated acute kidney injury (SA-AKI) remains unclear. Methods The data of patients with SA-AKI, identified based on the KDIGO criteria, were retrospectively collected from the Beth Israel Deaconess Medical Center between 2008 and 2019. SHR was calculated as follows: (glycemia [mmol/L]) / (1.59 x HbA1c [%] - 2.59). Primary outcomes were 30-day and 1-year mortality. The cumulative incidence of all-cause mortality was assessed using Kaplan-Meier survival analysis. Multivariable-adjusted logistic and Cox models and restricted cubic spline curves were used to analyze the correlation between SHR and all-cause mortality. Post-hoc subgroup analysis was performed to compare the effects of SHR across different subgroups. Results 1161 patients with SA-AKI were identified and categorized into four SHR quartiles as follows: Q1 (0.26, 0.90), Q2 (0.91, 1.08), Q3 (1.09, 1.30), and Q4 (1.31, 5.42). The median age of patients was 69 years, with 42.7% of the patients being women and 20.2% of the patients having chronic kidney disease. The 30-day and 1-year mortality were 22.1% and 35.0% respectively. Kaplan-Meier survival analysis indicated a gradual decrease in survival probability with increasing SHR quartiles. An increased SHR exhibited a strong correlation with 30-day mortality (hazard ratio [HR], 1.50; 95% confidence interval [CI], 1.18-1.90; P < 0.001) and 1-year mortality (HR, 1.32; 95% CI, 1.06-1.65; P = 0.014). SHR has a nonlinear relationship with 1-year mortality but not with 30-day mortality (P-nonlinear = 0.048 and 0.114, respectively). The results of subgroup analysis were mostly consistent with these findings. Conclusion An increased SHR is independently associated with 30-day and 1-year mortality in patients with SA-AKI. Therefore, SHR may serve as an effective tool for risk stratification in patients with SA-AKI.