Mortality, critical illness, and mechanical ventilation among hospitalized patients with COVID-19 on therapeutic anticoagulants.

Background: COVID-19 is associated with hypercoagulability and increased incidence of thrombosis. We compared the clinical outcomes of adults hospitalized with COVID-19 who were on therapeutic anticoagulants to those on prophylactic anticoagulation. Materials and methods: We performed an observational study of adult inpatients' with COVID-19 from March 9 to June 26, 2020. We compared patients who were continued on their outpatient prescribed therapeutic anticoagulation and those who were newly started on therapeutic anticoagulation for COVID-19 (without other indication) to those who were on prophylactic doses. The primary outcome was overall death while secondary outcomes were critical illness (World Health Organization Ordinal Scale for Clinical Improvement score ≥5), mechanical ventilation, and death among patients who first had critical illness. We adjusted for age, sex, race, body mass index (BMI), Charlson score, glucose on admission, and use of antiplatelet agents. Results: Of 1716 inpatients with COVID-19, 171 patients were continued on their therapeutic anticoagulation and 78 were started on new therapeutic anticoagulation for COVID-19. In patients continued on home therapeutic anticoagulation, there were no differences in overall death, critical illness, mechanical ventilation, or death among patients with critical illness compared to patients on prophylactic anticoagulation. In patients receiving new therapeutic anticoagulation for COVID-19, there was increased death (OR 5.93; 95% CI 3.71-9.47), critical illness (OR 14.51; 95% CI 7.43-28.31), need mechanical ventilation (OR 11.22; 95% CI 6.67-18.86), and death after first having critical illness (OR 5.51; 95% CI 2.80-10.87). Conclusions: Therapeutic anticoagulation for inpatients with COVID-19 was not associated with improved outcomes.