Doctors have discovered that patients who became severely infected with Covid-19 frequently developed kidney problems. Now, according to a significant study, kidney problems might linger for months after patients recover from the primary infection.

The study included data from 89,216 persons who tested positive for the Coronavirus between March 1, 2020, and March 15, 2021, as well as data from 1,637,467 people who were not Covid patients. It used information from patients in the Department of Veterans Affairs health system, according to the New York Times.

According to Dr. Ziyad Al-Aly, chief of the research and development department at the V.A. St. Louis Health Care System and senior author of the study, survivors with Covid-19 infection were 35% more likely than non-covid patients to have kidney damage one to six months after infection.

Because kidney dysfunction usually has dormant symptoms, any Covid-19 survivor needs to monitor kidney functions. 

Experts say one of the study's merits is that it includes nearly 1.7 million patients with complete electronic medical data, making it the biggest study on Covid-related kidney issues till now.

While the study results are unlikely to apply to all Covid patients, they do show that there's a notable long-term impact on kidney health in Covid-19 survivors, particularly those who were very sick during their acute illness, according to Dr. C. John Sperati, a nephrologist and associate professor of medicine at Johns Hopkins who was not involved in the study.

According to Dr. Al-Aly, the current study discovered that 4,757 Covid survivors lost at least 30% of their kidney function in the year after their infection.

Covid patients were also 25% more likely than those never infected to attain this degree of deterioration.