Anticoagulation Decreases Mortality in Patients Hospitalized With COVID-19

Does therapeutic anticoagulation decrease mortality in patients hospitalized with COVID-19?

Patients hospitalized with COVID-19 who do not require oxygen benefit from therapeutic (high) dosing, which reduces 28-day mortality compared with prophylactic (low) dosing. Major bleeding is more common with therapeutic doses. (Level of Evidence = 1a)

Researchers assembled the studies for this meta-analysis by searching two clinical trial databases through September 2024 for studies that compared high-dose anticoagulation with low-dose anticoagulation in participants hospitalized with COVID-19. The researchers followed PROSPERO guidelines for conducting a meta-analysis. In 11 studies of 6,297 patients, most of whom required little or no oxygen treatment, therapeutic-dose anticoagulation with low-molecular-weight heparin or unfractionated heparin reduced 28-day mortality (odds ratio = 0.77; 95% CI, 0.64–0.93) compared with prophylactic-dose anticoagulation. This result translates into a number needed to treat of 48 (95% CI, 30–160). Therapeutic doses were associated with a greater likelihood of major bleeding. Heterogeneity and risk of bias were low among the studies.

Study design: Meta-analysis (randomized controlled trials)

Funding source: Self-funded or unfunded

Setting: Inpatient (any location)

Reference: Vale CL, Godolphin PJ, Fisher DJ, et al.; WHO Rapid Evidence Appraisal for COVID-19 Therapies (REACT) Working Group. Anticoagulation among patients hospitalized for COVID-19: a systematic review and prospective meta-analysis. Ann Intern Med. 2025;178(1):59-69.

Editor’s Note: Dr. Shaughnessy is an assistant medical editor for AFP.