In a peer-reviewed paper published by the American Heart Association’s journal Circulation, researchers estimated that in 2020, COVID-19 resulted in more than 10,500 extra heart attacks, strokes and other blood clot-related events in England and the Wales. Although the excess risks were small overall and declined over time, the researchers found that the odds of developing a venous thromboembolism (VTE) after a COVID-19 diagnosis remained nearly double for up to 49 weeks after a positive test, in compared with people not diagnosed with a viral infection. VTEs are blood clots in the veins, which the US Centers for Disease Control and Prevention says is a serious and underdiagnosed, but preventable condition that can cause disability and death. A blood clot in the lungs is an example of VTE. Arterial thrombosis is a clot that develops in an artery and is also potentially dangerous. “We are confident that the risk falls fairly quickly – particularly for heart attacks and strokes – but the finding that it remains elevated for some time highlights the long-term effects of COVID-19 that we are just beginning to understand,” the study said. co-leader Jonathan Sterne, professor of medical statistics and epidemiology at the University of Bristol, said in a statement. Sterne is also director of the NIHR Bristol Biomedical Research Center and director of Health Data Research UK South West. Like previous studies on blood clots, the team led by the Universities of Bristol, Cambridge and Edinburgh and Swansea University also found that the risks of developing vascular disease rose “significantly higher” in the first one to two weeks after confirmation of COVID-19, a risk that has decreased over time. Unlike (the risk of?) arterial clots, which declined rapidly after initial infection, however, VTE risks remained higher. The researchers found that the relative rates of both arterial thrombosis and VTE remained higher for longer, especially in hospitalized patients. Overall, the team found that within the first week of testing positive for COVID-19, patients were 21 times more likely to develop artery-blocking clots, which can lead to heart attack and stroke. That risk dropped to 1.3 times more likely at some point after six months. For VTE, the increased risks increased from 33 times more likely in the first week, to 1.8 times between 27 and 49 weeks. Although there was little association between COVID-19 and blood clot risks by age, the researchers found that blacks and Asians, as well as those with a history of blood clots, were at higher risk compared to patients who were white. Those with only mild or moderate cases of COVID-19 were also affected, although the excess risk was generally lower than those with severe infections. “We showed that even people who were not hospitalized had a higher risk of blood clots in the first wave,” said Angela Wood, professor of biostatistics at the University of Cambridge and co-leader of the study. “While the risk to individuals remains small, the impact on public health may be significant, and strategies to prevent vascular events will be important as we continue the pandemic.” The research team used anonymised electronic health records across the entire population of England and Wales from 1 January to 7 December 2020 to analyze the data, which included examining the severity of a patient’s COVID-19 infection, the demographics of patients and their medical condition. history. The data collected would be before the mass vaccination campaign and before variants such as Delta and Omicron became dominant. “The large number of COVID-19 infections in England and Wales during 2020 and 2021 is likely to have caused a significant additional burden of arterial thrombosis and VTE,” the paper’s authors wrote, recommending preventive strategies such as a health review with primary care. doctor and high-risk patient management could help reduce the incidence of dangerous blood clots. They noted that the opposite happened during the pandemic — fewer patients visited doctors, which led to fewer routine health checkups for people with chronic medical conditions and fewer patient prescriptions for drugs that can help lower blood pressure and cholesterol. The researchers noted some limitations to the study, including the fact that patients who died in nursing homes from a clot-related event may not have been recorded as such, due to a lack of diagnostic resources for example. Some people who experience milder cases of blood clotting may also have avoided going to the doctor or hospital because of concerns about contracting COVID-19. The data collected also did not include information on some milder forms of clots. In addition, the authors noted that testing for COVID-19 was not widely available for mild or asymptomatic cases during the early days of the pandemic. Looking ahead, the researchers are studying data beyond 2020 to better understand how vaccinations and other variables affect vascular health.
