An evaluation of COVID-19 patients admitted to the hospital in Wuhan shows that they were at high risk of thromboembolic events and bleeding, as well as an increased risk of mortality. The use of anticoagulants, particularly parenteral anticoagulants, significantly reduced the risk of overall thromboembolic events, bleeding events, and mortality. The occurrence of atrial fibrillation contributed to systemic thromboembolism in COVID-19 patients.
COVID-19 patients are at high risk of thrombotic complications, which contribute to mortality rates. There is little data on systemic thromboembolism and the value for anticoagulation regimes is not clear.
Prof. Yutao Guo (Chinese PLA General Hospital, China) presented the study, which investigated the prevalence of systemic and venous thromboembolism, and severe bleeding and mortality associated with underlying risk factors and the effects of anticoagulation in hospitalized COVID-19 patients.
The study involved 1,125 COVID-19 subjects who were admitted to Union Hospital, Wuhan. Half of the participants (49.9%) were male and the average age was 58 years (36.3% were >65 years). They were observed for an average of 21 days. Of the participants, 33 (2.9%) underwent surgery and 249 subjects (22.1%) received anticoagulants, of which 7.7% received oral anticoagulants, 18.6% parenteral anticoagulants, and 4.2% oral and parenteral anticoagulants.
There were 82 thromboembolic events (7.3%; 37 systemic and 45 venous events), 128 major bleeding events (11.4%), and 91 deaths (8.1%). About 25 subjects (30%) with thromboembolism also experienced bleeding events. Age was an independent risk factor for thromboembolism, bleeding events, and mortality (all P<0.05).
After adjusting for the severity of COVID-19 infection, comorbidities, surgery, antiviral drugs, immunomodulators, Chinese herbal medicine, and antithrombotic drugs:
Atrial fibrillation or irregular rhythm increased the risk of systemic thromboembolism (HR 3.16; P=0.04).
Both oral anticoagulants (HR 0.32) and parenteral anticoagulants (HR 0.39) reduced the risk of thromboembolism (all P<0.001). After adjustment, parenteral anticoagulant administration had a borderline significant effect on both thromboembolism and bleeding events (HR 0.36; P=0.053), but significantly reduced the risk of overall outcome from thromboembolism, bleeding events, and mortality (HR 0.70; P=0.02).
Reference:
Guo Y. Risk factors for systemic and venous thromboembolism, mortality, and bleeding risk in 1125 patients with COVID-19: relationship to anticoagulation status. COVID and Cardiovascular Disease session, ESC Congress 2020, 30 Aug.