Early strategy vs. late initiation of renal replacement therapy in adult patients with acute kidney injury: an updated systematic review and meta-analysis of randomized controlled trials

OBJECTIVE: The optimal time to start renal replacement therapy (RRT) for acute kid-ney injury (AKI) remains controversial. We aim to compare the effects of early vs. delayed RRT initia-tion on clinical outcomes in adult patients with AKI.MATERIALS AND METHODS: PubMed, Em -base, Cochrane Library, Web of Science, Chi-nese Biomedical Literature Database, ClinicalTri-als.gov, and the International Clinical Trial regis-try platform were systematically searched from inception to 7 August 2022. The review included randomized clinical trials (RCTs) comparing early and delayed initiation of RRT in AKI patients. The selected primary outcomes were short-term and long-term mortality. Secondary outcomes includ-ed RRT dependency, intensive care unit (ICU) length of stay, hospital length of stay, mechanical ventilator-free days, vasoactive agents-free days, RRT-free days, and adverse events.RESULTS: Overall, 15 RCTs, including 5,625 pa-tients, were analyzed. Early RRT showed no sur-vival benefit when compared to the delayed thera- py (28-or 30-day mortality: RR, 1.01, 95% CI: 0.94-1.08, p = 0.87; 60-day mortality: RR, 0.87, 95% CI: 0.71-1.06, p = 0.16; 90-day mortality: RR, 1.00, 95% CI: 0.88-1.13, p = 0.97; in-hospital mortality: RR, 1.05, 95% CI: 0.88-1.24, p = 0.58; ICU mortality: RR, 1.00, 95% CI: 0.91-1.10, p = 0.98). The delayed RRT did not lead to a higher risk of RRT dependency, ICU, or hospital length of stay than the early RRT. Similarly, early initiation of RRT did not lead to longer ventilator-free, vasoactive agent-free, and RRT-free days. However, early RRT initiation was associated with more adverse events.CONCLUSIONS: Our study suggested that ear-ly RRT initiation was not associated with survival benefits or better clinical outcomes and increased the risk of RRT-associated adverse events. Cur-rent evidence does not support the use of early RRT for AKI patients without urgent indications.