Recovery after AKI: Effects on outcomes over 15 years

To examine the effect of kidney recovery on mortality, dialysis and kidney transplantation up to 15 years after AKI. We studied 29,726 survivors of critical illness and compared these outcomes stratified by AKI and recovery status at hospital discharge. Kidney recovery was defined as a return of serum creatinine to ≤150% of baseline without dialysis prior to hospital discharge. Overall AKI occurred in 59.2% in which two thirds developed stage 2–3 AKI. Recovery rate of AKI at hospital discharge was 80.8%. Patients who did not recover experienced the worst 15-year mortality compared to those who recovered and those without AKI (57.8% vs 45.2% vs 30.3%, p < 0.001). This pattern was also found in subgroups of patients with suspected sepsis-associated (57.1% vs 47.9% vs 36.5%, p < 0.001) and cardiac surgery-associated AKI (60.1% vs 41.8% vs 25.9%, p < 0.001). The rates of dialysis and transplantation at 15 years were low and not associated with recovery status. Recovery of AKI in critically ill patients at hospital discharge had an effect on long-term mortality for up to 15 years. These results have implications for acute care, follow-up and choice of endpoints for clinical trials.