Clinical Outcomes With the Use of Prophylactic Versus Therapeutic Anticoagulation in COVID-19

Background: This study is the first of its kind to assess the impact of preemptive therapeutic dose anticoagulation on mortality compared to prophylactic anticoagulation among COVID-19 patients. Its findings provide insight to clinicians regarding the management of COVID-19, particularly with the known prothrombotic state. Research Question: To determine the impact of anticoagulation on in-hospital mortality among COVID-19 positive patients with the a priori hypothesis that there would be a lower risk of in-hospital mortality with use of preemptive therapeutic over prophylactic dose enoxaparin or heparin. Study Design and Methods: Study Design: Retrospective cohort study from April 1 - April 25, 2020. The date of final follow-up was June 12, 2020. Setting: Two large, acute care hospitals in Western Connecticut. Participants: Five hundred and one inpatients were identified after discharge as 18 years or older and positive for SARS-CoV-2. The final sample size included 374 patients after applying exclusion criteria. Demographic variables were collected via hospital billing inquiries, while the clinical variables were abstracted from patients medical records. Exposure: Preemptive enoxaparin or heparin at a therapeutic or prophylactic dose. Main Outcome: In-hospital mortality. Results: When comparing preemptive therapeutic to prophylactic anticoagulation through multi-variable analysis, risk of in-hospital mortality was 2.3 times greater in patients receiving preemptive therapeutic anticoagulation (95% CI = 1.0, 4.9; p = 0.04). Interpretation: An increase in in-hospital mortality was observed with preemptive therapeutic anticoagulation. Thus, in the management of COVID-19 and its complications, we recommend further research and cautious use of preemptive therapeutic over prophylactic anticoagulation.