Therapeutic Doses of Anticoagulation Did Not Benefit Patients with COVID-19 and Elevated D-Dimer Levels

Compared with other respiratory infections, COVID-19 is associated with higher incidence of thromboembolic events — moreover, these complications are thought to be more likely in patients with elevated D-dimer concentrations. Observational studies have suggested that both therapeutic and prophylactic doses of anticoagulation may reduce risk for in-hospital death in such patients, but controlled studies are lacking. To address this question, researchers conducted an open-label trial at 31 Brazilian hospitals involving patients hospitalized with COVID-19 who had elevated D-dimer levels; patients with diagnosed venous thromboembolism (VTE) were excluded. Among 615 participants, 304 were randomized to standard prophylactic anticoagulation with heparin during hospitalization and 311 to therapeutic doses of anticoagulation with either rivaroxaban or heparin for 30 days.

Time to death, duration of hospitalization, and duration of supplemental oxygen through 30 days were not statistically significantly different between groups; nor was there a difference in incidence of individual thrombotic events at 30 days. However, clinically relevant bleeding occurred in 26 patients (8%) receiving therapeutic doses of anticoagulation and 7 (2%) receiving prophylactic anticoagulation (P=0.001).