Patients with
COVID-19 are at higher risk of
thrombosis due to the inflammatory nature of their disease. A higher-intensity approach to pharmacologic thromboprophylaxis may be warranted. The objective of this retrospective cohort study was to determine if a patient specific, targeted-intensity pharmacologic thromboprophylaxis protocol incorporating severity of illness, weight, and
biomarkers decreased incidence of
thrombosis in hospitalized patients with
COVID-19. Included patients were hospitalized with
COVID-19 and received thromboprophylaxis within 48 h of admission. Exclusion criteria included receipt of therapeutic anticoagulation prior to or within 24 h of admission, history of
heparin-induced
thrombocytopenia,
extracorporeal membrane oxygenation, pregnancy, or incarceration. Per-protocol patients received thromboprophylaxis according to institutional protocol involving escalated doses of
anticoagulants based upon severity of illness, total
body weight, and
biomarker thresholds. The primary outcome was
thrombosis. Secondary outcomes included major
bleeding, mortality, and identification of risk factors for
thrombosis. Of 1189 patients screened, 803 were included in the final analysis. The median age was 54 (42-65) and 446 (55.5%) were male. Patients in the per-protocol group experienced significantly fewer thrombotic events (4.4% vs. 10.7%, p = 0.002), less major
bleeding (3.1% vs. 9.6%, p < 0.001), and lower mortality (6.3% vs. 11.8%, p = 0.02) when compared to patients treated off-protocol. Significant predictors of
thrombosis included
mechanical ventilation and male sex. Post-hoc regression analysis identified
mechanical ventilation, major
bleeding, and D-dimer ≥ 1500 ng/mL FEU as significant predictors of mortality. A targeted pharmacologic thromboprophylaxis protocol incorporating severity of illness,
body weight, and
biomarkers appears effective and safe for preventing
thrombosis in patients with
COVID-19.