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By Alan Mozes<\/b>
HealthDay Reporter<\/i><\/p>\n
TUESDAY, Oct. 6, 2020 (HealthDay News)<\/p>\n
Hospitalized COVID-19<\/a> patients face an increased risk of developing dangerous blood clots<\/a>, a new review indicates.<\/p>\n The odds of a clot are highest for the most critically ill patients. Analysis of 66 studies found that 23% of COVID-19<\/a> patients in an intensive care unit (ICU) developed a blood clot in the leg<\/a>, known as a deep vein thrombosis<\/a> (DVT<\/a>).<\/p>\n Overall prevalence of a DVT<\/a> was 14% among ICU and non-ICU COVID-19<\/a> patients, and 8% among those with mild-to-moderate disease risk who were not admitted to the ICU.<\/p>\n The “numbers are surprisingly high when compared with other hospitalized patients,” said study author Dr. Cihan Ay.<\/p>\n Of great concern are blood clots<\/a> in the legs that can break away and travel to the lungs<\/a>. This is a life-threatening condition known as pulmonary embolism<\/a> (PE).<\/p>\n Nearly 4% of patients not admitted to the ICU developed a pulmonary embolism<\/a>. And “we found a very high PE risk of 14% in patients treated at an intensive care unit,” said Ay, an associate professor in hematology and hemostaseology at the Medical University of Vienna in Austria.<\/p>\n According to the American Heart<\/a> Association, DVT<\/a> and PE are each a form of venous thromboembolism, or VTE, as both refer to a blood clot<\/a> that originates in a vein.<\/p>\n VTE is estimated to affect between 300,000 and 600,000 Americans every year, the AHA notes. It is most frequently triggered by surgery, cancer<\/a>, hospitalization or long-term immobilization.<\/p>\n To examine VTE risk related to COVID-19<\/a>, Ay and his colleagues analyzed the findings of 66 studies, involving roughly 28,000 COVID-19<\/a> patients.<\/p>\n On average, the COVID-19<\/a> patients were about 63 years old, and six in 10 were men. About one-fifth had been admitted to an ICU.<\/p>\n None of the studies looked at clotting risk among COVID-19 patients who had not received hospital treatment. So the findings do not speak to DVT<\/a> or PE risk among such patients, said Ay, although “it seems that the risk of clots is low in patients with a mild clinical course of COVID-19.”<\/p>\n Early in the pandemic, it became clear that blood clot<\/a> risk seemed elevated in patients with COVID-19 compared to other diseases. To prevent clotting, “physicians worldwide intensified dosing of blood thinners for COVID-19 patients,” Ay said.<\/p>\n This created another potential problem, however, since blood thinners increase the risk of bleeding.<\/p>\n The study authors hope their review will offer clinicians more insight into clotting risk profiles, offering guidance as to which patients truly need preventive clot treatment, Ay said.<\/p>\n As to why COVID-19 might drive up clotting risk in the first place, Ay said experts can only speculate based on available data.<\/p>\n “First, the clinical course in such patients is often severe, which by itself increases the thrombosis [clotting] risk,” he said. “Second, researchers found that COVID-19 interacts with the blood clotting system and the blood vessels, which might explain the increased risk in those patients.”<\/p>\n Dr. Gregg Fonarow is director of the University of California, Los Angeles Cardiomyopathy<\/a> Center. He offered some additional specifics regarding that interaction.<\/p>\n “The virus SARS<\/a>-CoV-2 — which causes COVID-19 — has been shown to directly invade the cells that line blood vessels, endothelial cells,” he noted. “Endothelial injury can lead to venous thrombosis.”<\/p>\n In addition, extended bed rest or the placement of venous catheters during treatment for COVID-19 can also increase the risk for venous thrombosis, Fonarow noted.<\/p>\n The study results were published online recently in Research and Practice in Thrombosis and Haemostasis<\/i>.<\/p>\n ![\"MedicalNews\"](\"https:\/\/images.medicinenet.com\/images\/HealthDay\/healthday.png\")
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