Vaccination Tied to Better Survival in COVID-Linked AKI

TOPLINE: 

Among patients hospitalized with COVID and acute kidney injury (AKI), unvaccinated individuals had longer hospital stays, more frequent need for continuous renal replacement therapy, higher dependence on dialysis at discharge, and substantially higher rates of in-hospital and long-term mortality than their vaccinated peers.

METHODOLOGY:

• AKI affects up to 28%-46% of patients hospitalized with COVID, with effects ranging from mild decline in renal function to dependency on dialysis; however, long-term renal and survival outcomes of these patients remain poorly understood.
• Researchers conducted a single-center cohort study to evaluate renal outcomes in 972 vaccinated and unvaccinated patients with COVID and AKI admitted to a large urban academic quaternary care hospital from March 1, 2020, to March 30, 2022.
• Among the included patients, 411 (median age at COVID diagnosis, 67 years; 37% women) were unvaccinated, whereas 467 (median age at COVID diagnosis, 67.4 years; 38.5% women) had received at least two primary-series doses of the Pfizer-BioNTech or Moderna mRNA COVID vaccine or a single dose of the Johnson & Johnson Janssen COVID vaccine prior to hospitalization.
• The primary outcome was in-hospital mortality, whereas secondary outcomes included long-term mortality, length of hospital stay, and need for renal replacement therapy at discharge.
• The median follow-up duration was 232 days.

TAKEAWAY:

• Unvaccinated patients had significantly higher rates of in-hospital mortality (adjusted hazard ratio [HR], 5.54; 95% CI, 3.36-9.13) and long-term follow-up mortality (adjusted HR, 4.78; 95% CI, 3.39-6.73) than vaccinated patients.
• They were also more likely to require continuous renal replacement therapy during hospitalization than vaccinated patients (15.8% vs 10.9%; P = .03); the need for this therapy was associated with increased risks for in-hospital death (adjusted HR, 2.82; 95% CI, 1.88-4.25) and long-term mortality (adjusted HR, 2.44; 95% CI, 1.73-3.42).
• Unvaccinated patients had higher odds of being discharged on renal replacement therapy (odds ratio, 2.56; 95% CI, 1.52-4.30) and had a significantly longer median length of hospital stay (12 days vs 8 days) than vaccinated patients.

IN PRACTICE:

“Patients who completed the primary vaccine series with COVID-19 infection and AKI had a lower mortality rate and were less likely to remain on renal replacement therapy at the time of discharge,” the authors wrote.

SOURCE:

This study was led by Niloofar Nobakht, MD, Division of Nephrology, Department of Medicine, David Geffen School of Medicine at the University of California, Los Angeles. It was published online on June 17, 2025, in Kidney Medicine.

LIMITATIONS:

Missing baseline creatinine data limited the ability to stage AKI and likely contributed to the significant differences in AKI staging observed between the vaccinated and unvaccinated cohorts. This study lacked data on ventilation status and other indicators of infection severity in patients admitted to ICUs who received continuous renal replacement therapy. Information regarding COVID booster vaccinations was not available.

DISCLOSURES:

One author received support from the National Institutes of Health, the Smidt Family Foundation, the Factor Family Foundation, the Davita Allen Nissenson Research Fund, and the Ralph Block Family Foundation.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.