The previous research mentioned that catching Covid was linked with an increased incidence of blood clots, it was unclear how long this risk persisted and whether mild infections also increased people’s risk.
To address these uncertainties, Anne-Marie Fors Connolly of Umea University in Sweden, and her colleagues from the United Kingdom, and Finland.
In this observational study, They have assessed the risk of DVT, pulmonary embolism (a blood clot on the lung), and various types of bleeding, such as gastrointestinal bleeding or a burst blood vessel in the brain, between February 2020 and May 2021, 1 057 174 people who tested positive for SARS-CoV-2 in Sweden were matched to 4 076 342 control participants based on age, gender, and county of residence.
401 cases of DVT were observed among COVID-19 patients during the study period, compared to 267 cases among negative patients.
In the meantime, there were 1,761 cases of PE among virus patients compared to 171 cases among control patients.
Covid-19 patients were more likely to develop blood clots if they had underlying conditions, had a severe case of the virus, or were infected during the pandemic’s first wave in early 2020.
In the 30 days following infection, they discovered a 33-fold increase in the risk of pulmonary embolism, a fivefold increase in the risk of DVT, and a nearly twofold increase in the risk of bleeding.
People were at increased risk of pulmonary embolism for 6 months after becoming infected, and for bleeding and DVT for two and three months, respectively.
Although the risks were largest in patients with more severe illness, even those with mild Covid had a threefold increase in DVT and a sevenfold increase in pulmonary embolism.
There was no increased risk of bleeding in those who had mild infections.