Folks with gentle Covid had been at elevated threat of blood clots: UK examine

A patient undergoes a coronavirus disease (COVID-19) test on December 27, 2021 at Sparrow Laboratories Drive-Thru Services in Lansing, Michigan.

Emily Elconin | Reuters

People who got mild cases of Covid-19 in the first year of the pandemic were at a higher risk of developing blood clots than those who were not infected, according to a major study published this week by British scientists.

Patients with mild Covid, defined as those who were not hospitalized, were 2.7 times more likely to develop blood clots, according to the study published in the British Medical Journal’s Heart on Monday. They were also ten times more likely to die than people without Covid.

Scientists from Queen Mary University of London tracked 18,000 people who contracted Covid in the first year of the pandemic and compared their health outcomes to nearly 34,000 people who did not contract the virus.

Participants were followed until they developed cardiovascular disease, died, or until the study ended in March 2021. Most of the study was conducted before the vaccines were launched in the UK in December 2020.

While people with mild Covid were at an increased risk of blood clots, patients hospitalized with the virus were at significantly higher risk of cardiovascular disease in general. The risk of cardiovascular disease was highest in mild and severe cases in the first 30 days after infection, but continued later.

Additionally, patients hospitalized with Covid were 28 times more likely to develop blood clots, 22 times more likely to develop heart failure and 17 times more likely to have a stroke, according to the study. Overall, they were over 100 times more likely to die than people without Covid.

The scientists said their findings underscore the importance of long-term surveillance for cardiovascular disease even in people with mild Covid.

“Our findings underscore the increased cardiovascular risk of individuals with a prior infection, which is likely greater in countries with limited access to vaccination and thus greater population exposure to COVID-19,” the study authors wrote.

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