Dialysis Dependence in Standard versus Accelerated Initiation of KRT in AKI: A Post Hoc Analysis

Key Points The Standard versus Accelerated Initiation of Renal Replacement Therapy in AKI trial found that starting dialysis earlier for AKI resulted in a 74% higher risk of still receiving dialysis at 90 days.Among patients who likely would have started dialysis under usual practice, the risks of dialysis dependence were similar.This suggests much of the risk observed may have been due to starting dialysis (versus never starting) rather than starting slightly earlier. Background The Standard versus Accelerated Initiation of Renal Replacement Therapy in AKI Trial showed that among critically ill patients with AKI, an accelerated KRT initiation strategy resulted in more KRT dependence at 90 days, as compared with a standard strategy. However, it is unclear whether this difference exists among participants who likely would have been treated with KRT in usual practice. Methods Secondary analysis of the Standard versus Accelerated Initiation of Renal Replacement Therapy in AKI randomized controlled trial, analyzing participants who received more than the median number of days of KRT, which served as a proxy for high probability of requiring KRT under usual practice. Two sensitivity analyses redefined the cohort as (1) those with ≥24 hours of oliguria who received KRT and (2) those who received any KRT. Using the same statistical approach as the original trial, we calculated unadjusted relative risks with 95% confidence intervals (CIs) for the exposure of randomized KRT initiation strategy (accelerated versus standard) on the outcome of KRT dependence at 90 days among survivors. Results Among the 1184 participants who received ≥6 days of KRT (670 and 514 in the accelerated and standard arms, respectively), baseline characteristics remained balanced between treatment arms. The relative risk of KRT dependence at 90 days was attenuated and nonsignificant: 1.21 (95% CI, 0.84 to 1.78), compared with 1.74 (95% CI, 1.24 to 2.43) in the overall trial. The results were similar in sensitivity analyses. Conclusions Among patients who likely would have been treated with KRT in usual practice, there was no significant difference in 90-day KRT dependence among survivors between those randomized to the accelerated and standard KRT initiation strategies. These results suggest that the harm of long-term KRT dependence may be largely due to KRT initiation (versus never initiation) rather than earlier initiation. Clinical Trial registry name and registration number: NCT02568722.