Effect of nephrology follow-up on long-term outcomes in patients with acute kidney injury: A systematic review and meta-analysis

Aim: Acute kidney injury (AKI) is associated with poor short-term and long-term clinical outcomes. The role of nephrology follow-up in post-AKI management remains uncertain.

Methods: A systematic review and meta-analysis were performed examining all randomized controlled trials and observational studies assessing the effect of nephrology follow-up on patients' clinical outcomes. The primary outcome was all-cause mortality. The secondary outcomes were renal outcomes, which were defined as a composite of requirement of permanent dialysis and recurrent AKI. Pooled analysis was performed using a random-effect model.

Results: We identified six studies (8972 patients, mean follow-up of 49 months). Five were retrospective cohort studies and one was a prospective cohort study. Risk of bias was a concern with all studied. Only four studies reported primary and/or secondary outcomes and were included. Compared with patients without nephrology follow-up, patients with nephrology follow-up had significantly reduced mortality by 22% (three studies, 3240 patients, relative risk [RR] = 0.78, 95% confidence interval [CI] = 0.70-0.88, I² = 0.0%). Nephrology follow-up did not improve composite renal outcomes with high heterogeneity due to significant differences in reported renal outcomes and follow-up period (two studies, 2537 patients, RR = 1.72, 95% CI = 0.49-6.05, I² = 90.1%).

Conclusion: Current evidence from observational studies is biased. It suggests long-term survival benefits with post-discharge nephrology follow-up in AKI patients. However, due to its low quality, such evidence is only hypothesis-generating. Nonetheless, it provides a rationale for future randomized controlled trials of nephrology follow-up in AKI patients. SUMMARY AT A GLANCE The present meta-analysis assessed the effect of nephrology follow-up on patients' clinical outcomes, and suggested long-term survival benefits in acute kidney injury (AKI) survivors. Although the study inherently comprises potential risks of bias due to paucity of available data, the results provide a rationale for future randomized controlled trials.