COVID-19-associated venous thromboembolism: risk of recurrence and major bleeding.

Background: Complications under anticoagulant treatment in patients with COVID-19-associated venous thromboembolism (VTE) have not been consistently reported.

Objectives: This study aimed to compare the 90-day rates of VTE recurrences and major bleeding in patients with COVID-19-associated VTE versus those with VTE without COVID-19.

Methods: We used the RIETE registry to compare the 3-month outcomes in patients with COVID-19-associated VTE versus those with VTE without COVID-19.

Results: The study included 1,747 patients with COVID-19-associated VTE and 8,711 with VTE without COVID-19. Patients with COVID-19-associated VTE were more likely to be hospitalized at baseline and to present with pulmonary embolism. During the first 90 days, 123 patients (1.17%) developed VTE recurrences, and 266 (2.54%) experienced major bleeding. Patients with COVID-19-associated VTE had a similar rate of VTE recurrences (0.9% vs 1.2%) but a higher rate of major bleeding (4.6% vs 2.1%;  < .001) than those without COVID-19. Multivariable analysis adjusted for competing risks showed that patients with COVID-19-associated VTE had an increased risk of major bleeding (subhazard ratio, 1.395; 95% confidence interval, 1.037-1.877). The 30-day mortality after major bleeding was 26.3% in patients with COVID-19-associated VTE and 17.7% in those without COVID-19.

Conclusion: Patients with COVID-19-associated VTE had a 5-fold higher rate of major bleeding than VTE recurrences during the first 90 days of anticoagulation. In VTE patients without COVID-19, both rates were similar. These findings highlight the importance of carefully monitoring and optimizing anticoagulation in these patients.