'Long COVID' can cause loss of smell and kidney problems
COVID-19 symptoms that persist long after infection, known as "long COVID", has been tied to a higher risk for new kidney problems, according to a new study.
Analyzing data on more than 1.7 million U.S. veterans, including nearly 90,000 COVID-19 survivors with symptoms lasting at least 30 days, researchers found the "long haulers" were at higher risk for new kidney problems compared to people who had not been infected with the coronavirus.
This was true even when survivors had not been hospitalized, although declines in kidney function were "more profound" with more severe infection, they reported on Wednesday in the Journal of the American Society of Nephrology.
Roughly 5% of the Long COVID group developed at least a 30% drop in a critical measure of kidney function known as the estimated glomerular filtration rate, or eGFR.
Overall, people with long COVID were 25% more likely than uninfected people to develop a 30% decline in eGFR, with higher risks in survivors of more severe disease.
While kidney function often declines with age, the damage in these patients "was in excess" of what happens with normal aging, study coauthor Dr. Ziyad Al-Aly, of Washington University in St. Louis, said in a statement. "Our findings emphasize the critical importance of paying attention to kidney function and disease in caring for patients who have had COVID-19," he said.
Loss of smell may be followed by smell distortions
Many people who lose their sense of smell due to COVID-19 eventually regain it, but some survivors later report smell distortions and unexplained smells, a new study found.
Researchers analyzed survey responses from 1,468 individuals who had been diagnosed with COVID-19 between April and September 2020 and had suffered loss of smell and taste at the start of their illness.
Early on, about 10% also reported smell distortions, or parosmia, and unexplained smells, known as phantosmia. At an average of six to seven months after becoming ill and first reporting loss of smell, roughly 60% of women and 48% of men had regained less than 80% of their pre-illness smell ability, and rates of smell distortions and imaginary smells had increased, the researchers reported on Tuesday on medRxiv ahead of peer review.
Roughly 47% reported parosmia, saying, for example, "some things now smell like chemicals." About 25% reported phantosmia. "Sometimes I can smell burning but no one else around me can," one respondent reported. Persistent smell problems were seen more often in survivors with more symptoms overall, "suggesting it may be a key marker of long-COVID," the authors said.