NEW YORK • Hundreds of thousands of Americans have sought medical care for post-coronavirus health problems that they had not been diagnosed with before becoming infected, according to the largest study to date of long-term symptoms in Covid-19 patients.
The study, tracking the health insurance records of nearly two million people in the United States who contracted the coronavirus last year, found that one month or more after their infection, almost one quarter - 23 per cent - of them sought medical treatment for new conditions. Those affected were all ages, including children.
Their most common new health problems were pain, including in nerves and muscles; breathing difficulties; high cholesterol; malaise and fatigue; as well as high blood pressure.
Other health issues included intestinal symptoms, migraines, skin problems, heart abnormalities, sleep disorders, as well as mental health conditions like anxiety and depression.
Post-coronavirus health problems were common even among people who had not fallen sick from the virus at all, the study found.
While nearly half of the patients who were hospitalised for Covid-19 experienced subsequent medical issues, so did 27 per cent of people who had mild or moderate symptoms and 19 per cent of people who said they were asymptomatic.
"One thing that was surprising to us was the large percentage of asymptomatic patients that are in that category of long Covid-19," said Ms Robin Gelburd, president of Fair Health, a non-profit organisation that conducted the study based on what it says is the nation's largest database of private health insurance claims.
More than half of the 1,959,982 patients whose records were evaluated reported no symptoms from their Covid-19 infection.
Forty per cent had symptoms but did not require hospitalisation, including 1 per cent whose only symptom was loss of taste or smell; only 5 per cent were hospitalised.
Ms Gelburd said the fact that asymptomatic people can have post-Covid-19 symptoms is important to emphasise, so that patients and doctors can know to consider the possibility that some health issues may really be after-effects of the coronavirus.
"There are some people who may not have even known they had Covid-19," she said. "But if they continue to present with some of these conditions that are unusual for their health history, it may be worth some further investigation by the medical professional that they're working with."
The report analysed records of people diagnosed with Covid-19 between February and December last year, tracking them until February this year.
It found that 454,477 people consulted health providers for symptoms 30 days or more after their infection.
Fair Health said the analysis was evaluated by an independent academic reviewer but was not formally peer-reviewed.
"The strength of this study is really its size and its ability to look across the range of disease severity in a diversity of age groups," said Dr Helen Chu, an associate professor of medicine and infectious diseases at the University of Washington School of Medicine, who was not involved in the report. "This is a hard study to do with that much data."
The report "drives home the point that long Covid-19 can affect nearly every organ system", said Dr Ziyad Al-Aly, chief of research and development at the VA St Louis Health Care System, who was not involved in the study.
"Some of these manifestations are chronic conditions that will last a lifetime and will forever scar some individuals and families," added Dr Al-Aly, who was an author of a large study published in April of lingering symptoms in coronavirus patients in the Department of Veterans Affairs health system.
NYTIMES
