Vaccinated COVID-19 Patients with AKI Have Better Outcomes, Less Likely to Require Dialysis: RECOVID Study
USA: A recent study published in Kidney Medicine revealed that COVID-19 patients who developed acute kidney injury (AKI) had shorter dialysis duration and lower mortality rates if they were vaccinated, compared to unvaccinated AKI patients.
The retrospective single-center study, led by Dr. Niloofar Nobakht from the Division of Nephrology at the David Geffen School of Medicine, UCLA, examined the long-term kidney outcomes and survival in hospitalized patients with COVID-19-associated AKI. Although AKI is a frequent and serious complication of COVID-19, affecting up to 32%-46% of hospitalized patients, there has been limited understanding of how vaccination status impacts renal recovery and mortality in these cases.
The study analyzed data from 972 adult patients hospitalized with COVID-19 and AKI between March 1 and March 30, 2022, at a large urban academic hospital. Of these, 411 patients (42.3%) were unvaccinated, while 467 patients (48.0%) had completed their primary vaccination series.
Researchers compared outcomes between vaccinated and unvaccinated patients, focusing on in-hospital mortality as the primary outcome, with secondary outcomes including length of hospital stay, dialysis requirements at discharge, and long-term survival. The analysis used Kaplan-Meier survival estimates, log-rank tests, and multivariable regression models.
The study led to the following findings:
- Unvaccinated patients had a higher need for continuous renal replacement therapy (CRRT) during hospitalization (15.8%) compared to vaccinated patients (10.9%), with statistical significance.
- CRRT use was strongly linked to in-hospital mortality (adjusted hazard ratio [HR] 2.82).
- CRRT use was also strongly associated with long-term mortality (adjusted HR 2.44).
- Unvaccinated patients were 2.56 times more likely to be discharged with ongoing dialysis needs than vaccinated patients.
- Unvaccinated patients had more than a fivefold higher risk of in-hospital death compared to vaccinated individuals (adjusted HR 5.54).
- Unvaccinated patients had nearly five times greater risk of long-term mortality after discharge compared to vaccinated patients (adjusted HR 4.78).
While the study highlights the protective effect of vaccination, the authors acknowledged certain limitations — specifically, the absence of data regarding ventilator use and disease severity in ICU patients, as well as the lack of information on booster vaccination status.
The authors conclude, "Patients with COVID-19-associated AKI who had completed their primary vaccination series experienced better survival outcomes and were less likely to remain dialysis-dependent at discharge. The study emphasizes the importance of vaccination in improving renal and overall outcomes in this high-risk population."
The authors emphasized the need for further research to better understand the causes of COVID-19-associated AKI and to develop strategies for optimizing long-term kidney care, especially as more patients continue to face lingering symptoms and organ dysfunction after recovering from COVID-19.
Reference:
Nobakht N, Jang C, Grogan T, Fahim P, Kurtz I, Schaenman J, Wilson J, Kamgar M, on behalf of the RECOVID Investigators, RECOVID: Retrospective Observational Study of Renal Outcomes and Long-Term Mortality in Patients With COVID-19 Associated AKI, A Comparison Between Vaccinated and Unvaccinated Patients, Kidney Medicine (2025), doi: https://doi.org/10.1016/j.xkme.2025.101020.
