Vaccination linked to better kidney outcomes in hospitalized COVID-19 patients

Vaccinated patients hospitalized with COVID-19 who developed acute kidney injury had better outcomes than unvaccinated patients with the same condition, new research suggests. The study found vaccinated patients were less likely to stay on dialysis after discharge, and more likely to survive, than unvaccinated patients.

Acute kidney injury, or AKI, is common among people infected with COVID-19, with rates running as high at 46%. It can lead to a mild decrease in kidney function or, if severe enough, to dialysis. The long-term renal and survival outcomes of these patients, however, has not been well understood.

The findings, to be published June 13 in the peer-reviewed journal Kidney Medicine, suggest that COVID-19 vaccination can reduce long-term kidney function decline and mortality risk, said lead author Dr. Niloofar Nobakht, health sciences clinical associate professor of medicine in the division of nephrology at the David Geffen School of Medicine at UCLA.

The COVID-19 vaccine is an important intervention that can decrease the chances of developing complications from the COVID-19 infection in patients hospitalized with acute kidney injuries. It is important for individuals to discuss the benefits of getting vaccinated for COVID-19 with their doctors as it can decrease the chances of needing dialysis, which can severely affect the quality of life of patients and lead to further complications including death."

Dr. Niloofar Nobakht, health sciences clinical associate professor of medicine, division of nephrology, David Geffen School of Medicine, UCLA

The researchers analyzed about 3500 patients hospitalized with COVID-19 between March 1, 2020 and March 30, 2022. Of those patients, 972 developed acute kidney injury, with 411 (42.3%) unvaccinated and 467 (48%) having received at least two doses of the Pfizer or Moderna mRNA vaccines or one dose of Johnson & Johnson's vaccine.

They found that 65 (15.8%) unvaccinated patients were more likely to need a type of dialysis for critically ill patients called continuous renal replacement therapy (CRRT) compared with 51 (10.9%) vaccinated patients.

In addition, they also found that unvaccinated patients had 2.56 times the odds of needing CRRT after hospital discharge, 5.54 times the risk of dying in the hospital and 4.78 times higher risk of dying during long-term follow-up compared with vaccinated patients.

Among the study's limitations, the researchers were missing baseline data for creatinine, which may have contributed to the difference in AKI between the vaccinated and unvaccinated patients. They also lacked data on severity of COVID-19 illness, though they noted that the patients were all ill enough to have required hospitalization. They also did not include the effects of booster vaccinations.

"This study also emphasizes the importance of the need for continued research in understanding how COVID-19 infections affect the kidney and how we should manage and monitor kidney complications from COVID-19 infections to improve patient outcomes," Nobakht said.

Co-authors are Dr. Charley Jang, Tristan Grogan, Dr. Peter Fahim, Dr. Ira Kurtz, Dr. Joanna Schaenman, Dr. James Wilson, and Dr. Mohammad Kamgar of UCLA.

The study was funded by the National Center for Advancing Translational Science (NCATS) of the National Institutes of Health under the UCLA Clinical and Translational Science Institute (UL1TR001881).