Predictors of early mortality in critically ill patients with acute kidney injury necessitating renal replacement therapy: A cohort study.

Abstract

Reliable prediction of early mortality after initiation of renal replacement therapy (RRT) in critically ill patients may inform decision-making regarding this treatment. Our primary objective was to identify predictors of mortality within 2days of starting RRT. Patients with acute kidney injury (AKI), receiving RRT, and admitted to intensive care units of one hospital were included. Associations between baseline risk factors and mortality at 2days and at hospital discharge were analyzed using logistic regression. Discrimination of both models was assessed. We included 626 patients, treated initially with intermittent RRT (n=300, 47.9%), continuous RRT (n=211, 33.7%), or sustained low-efficiency dialysis (n=115, 18.4%). Two-day mortality after starting RRT was 12.9% (n=81), and hospital mortality was 50.5% (n=316). Independent predictors of 2-day mortality included primary diagnostic category (p=0.004) and sepsis-related organ failure assessment (SOFA) score (odds ratio [OR] 1.36 per point, 95% confidence interval [CI] 1.24-1.50). Independent predictors of hospital mortality included SOFA (1.29, 95%CI 1.21-1.37), Charlson score (1.20, 95%CI 1.18-1.43), and interhospital transfer (OR 0.55, 0.38-0.81). C-statistics were 0.81 (2-day mortality) and 0.80 (hospital mortality). Higher SOFA was associated with 2-day mortality after RRT initiation and with hospital mortality. Discrimination in both models was modest.