Abstract 15752: Acute Kidney Injury and Shock Severity for Mortality Risk Stratification in Cardiac Intensive Care Unit Patients

Abstract

Introduction: Acute kidney injury (AKI) is a highly prevalent risk factor for mortality among patients with cardiogenic shock (CS). We sought to assess the incidence and prognostic relevance of AKI as a function of shock severity in unselected Cardiac Intensive Care Unit (CICU) patients, as measured by the Society for the Cardiovascular Angiography and Interventions (SCAI) shock stage. Methods: We retrospectively reviewed admissions to the Mayo Clinic from 2007 to 2015 and stratified patients by the SCAI shock stage. AKI was defined and staged based on changes in serum creatinine during hospitalization as per KDIGO guidelines. Predictors of in-hospital mortality were analyzed using Kaplan-Meier survival analysis, and one-year mortality was analyzed using Cox proportional-hazards analysis. Results: The final study population included 10,004 unique patients with a mean age of 67 years and 37% females. The percentage of patients with SCAI shock stages A, B, C, D, and E were 47%, 30%, 15%, 7%, and 1%, respectively. AKI of any severity occurred in 51% of patients during hospitalization, including severe (stage 2/3) AKI in 16%. The incidence of AKI and severe AKI increased with the SCAI shock stage. Hospital mortality occurred in 8% of patients and increased as a function of the AKI stage and SCAI shock stage. AKI was associated with increased hospital mortality after multivariable adjustment (adjusted OR per AKI stage 1.17, 95% CI 1.05-1.30, p=0.005). Twenty-one percent of patients died within one year of CICU admission, and worse AKI was associated with increased one-year mortality (adjusted HR per AKI stage 1.11, 95% CI 1.05-1.18, p=<0.001). Hospital survivors with AKI of any severity had higher mortality compared with patients who did not have AKI (p<0.001). Conclusions: AKI was increasingly common in CICU patients with higher shock severity. In-hospital and one-year mortality risk increased as a function of the severity of AKI and the SCAI shock stage. This analysis emphasizes the importance of AKI as a complication of shock and as a predictor of adverse outcomes in CICU patients.