A high rate of thromboembolism and a high risk of death have been reported regarding hospitalized patients with coronavirus disease 2019 (COVID-19). Recently, we noticed that clinicians in some comparative studies used direct oral anticoagulants (DOACs) to prevent thromboembolism in patients with COVID-19. However, it is uncertain whether DOACs are better than recommended heparin for hospitalized patients with COVID-19. Therefore, a direct comparison of the prophylactic effects and safety between DOACs and heparin is needed. We systematically searched PubMed, Embase, Web of Science, and the Cochrane Library from 2019 to December 1, 2022. Randomized controlled trials or retrospective studies comparing the efficacy or safety of DOACs with that of heparin in preventing thromboembolism for hospitalized patients with COVID-19 were included. We assessed endpoints and publication bias using Stata 14.0. Five studies comprising 1360 hospitalized COVID-19 patients with mild to moderate cases were identified in the databases. Comparing the embolism incidence, we found that DOACs had a better effect than heparin, mainly low-molecular-weight heparin (LMWH), in preventing thromboembolism (risk ratio [RR] = 0.63, 95% confidence interval [CI] [0.43-0.91], P = 0.014). Considering safety, DOACs resulted in less bleeding than heparin during hospitalization (RR = 0.52, 95% CI [0.11-2.44], P = 0.411). Similar mortality was discovered in the 2 groups (RR = 0.94, 95% CI [0.59-1.51], P = 0.797). In noncritically hospitalized patients with COVID-19, DOACs are superior to heparin, even LMWH, in preventing thromboembolism. Compared with heparin, DOACs have a lower trend of bleeding and yield a similar mortality rate. Therefore, DOACs may be a better alternative for patients with mild to moderate COVID-19.
Keywords: COVID-19; direct oral anticoagulants; heparin; meta-analysis; thromboembolism.