COVID-19 Increases Your Risk For Blood Clots Longer Than You Think

Conditions in which blood over-coagulates as it circulates throughout the body are referred to as hypercoagulable states, leading to an increased risk for the development of blood clots, reports the Cleveland Clinic. While one's risk for blood clots is often influenced by genetics, such blood disorders can also develop as the result of certain medical conditions. This was the subject of new research published in The British Medical Journal, in which researchers aimed to identify the length of time that patients are at risk for developing deep vein thrombosis, pulmonary embolism, and bleeding disorders following a COVID-19 infection.

Researchers examined data from over 1 million patients across Sweden who had been diagnosed with a positive case of COVID-19 between February 2020 through May 2021 and compared them to a control group of over 4 million individuals who had tested negative for infection. The results indicated that COVID-19-positive patients were at an increased risk for deep vein thrombosis, pulmonary embolism, and bleeding for several months post-infection.

Blood clotting risk was highest among those with severe COVID-19

As reported by Healthline, researchers of the BMJ study determined the risk for deep vein thrombosis was highest among COVID-19 patients for 70 days following infection. Patient bleeding risk increased for two months following infection, and the risk for pulmonary embolism was shown to persist for the longest period of time — for 110 days after viral infection. While these numbers indicate when risk was at its most high, Dr. Becker, a professor and director of the UC Heart, Lung and Vascular Institute and the UC Division of Cardiovascular Health and Disease at the UC College of Medicine, told Healthline that overall " ... the risk of deep vein thrombosis and pulmonary embolism persists for at least six months after initial infection."

Study findings also determined that while the risks for deep vein thrombosis and pulmonary embolism were present for even mild cases of COVID-19, they were highest amongst those with severe infection. However, blot clot risk appeared to have decreased in subsequent waves of the pandemic, with the risk being highest during the first wave. Scientists acknowledged that the lack of testing availability during the first wave of the pandemic may have influenced study results, as well as subsequent improvements in vaccination rates and treatment options.