Ambulatory COVID-19 patients (those diagnosed as outpatients) face an elevated risk of venal thrombosis (blood clot in a vein) than the general population not affected by COVID-19, according to a new Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences (NDORMS) study. But the risk was greatly reduced in fully vaccinated people with breakthrough infection.
Published in JAMA Internal Medicine the retrospective, population-based cohort study examined records of over 400,000 participants from the UK Biobank. 18,818 were infected with SARS-CoV-2 identified by a positive PCR test in community settings, and these were matched against 93,179 uninfected participants according to age, gender and a series of clinical features.