Epidemiology of Septic Shock Associated Acute Kidney Injury: A National Retrospective Cohort Study

OBJECTIVES: Septic shock is the most severe and final stage of sepsis. These patients may have a higher risk for sepsis-associated acute kidney injury (AKI). The purpose of this study is to determine the frequency of AKI, major adverse kidney events at 30 days (MAKE-30), and use of renal replacement therapy (RRT) in patients with septic shock. We also aim to determine the association between stage of AKI and in-hospital mortality. DESIGN: Retrospective, multicenter, cohort study. SETTING: This was conducted in 220 geographically diverse community and teaching hospitals across the United States. PATIENTS: Adult patients were included if they had septic shock on hospital admission. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Measurements include stage 1, 2, and 3 AKI, RRT, and MAKE-30. Of the 21,803 patients included in the final cohort, 92.8% had AKI during hospital admission. Patients had a mean (sd) age of 66.0 years (15.1 yr), 48.6% were female, 29.5% had chronic kidney disease, and mean (sd) estimated glomerular filtration rate was 35.8 mL/min/1.73 m² (24.3 mL/min/1.73 m²). The maximum stage of AKI during hospitalization was none (7.2%), stage 1 (22.9%), stage 2 (27.3%), or stage 3 (42.7%). The proportion of patients who received RRT was 6.4%. MAKE-30 occurred in 42.0% and 30.9% died. There was no significant association between stage 1 (odds ratio [OR], 1.12; 95% CI, 0.97-1.29; p = 0.109), but there was a significant association between stage 2 (OR, 1.25; 95% CI, 1.09-1.43; p = 0.001), and stage 3 AKI (OR, 1.66; 95% CI, 1.46-1.89; p < 0.001) and mortality. CONCLUSIONS: Among hospitalized patients with septic shock, most patients have AKI, and stage 3 AKI is associated with the highest risk of mortality.