Anticoagulation for patients discharged from the emergency department with venous thromboembolism

Direct oral anticoagulants (DOACs) are increasingly being used over low molecular weight heparin (LMWH) and vitamin K antagonists for the treatment of venous thromboembolism (VTE). The objective of this study was to examine predictors of anticoagulant type (DOAC vs. LMWH) prescribed at discharge from the emergency department (ED) among patients diagnosed with VTE in the ED.

We conducted a retrospective chart review of adult (>17 years) patients discharged from an Ontario, Canada ED in a tertiary care centre with an ED diagnosis of deep vein thrombosis or pulmonary embolism from January 2019 to December 2021. A multivariable logistic regression model was used to examine the predictors of the anticoagulant (DOAC vs. LMWH) prescribed at discharge. Covariables included: age, sex, history of major bleeding, history of cancer, and previous anticoagulation.

VTE was confirmed in 390 ED visits by 365 unique patients. Among unique patients, 239 (65.5 %) patients were discharged from the ED and included in analysis. Of the 239 patients included, 12.1 % of patients were over the age of 80, 46.4 % were female and 29.7 % had a history of cancer. The majority of patients discharged from the ED were prescribed DOACs (70.7 %,169/239). Cancer history was associated with anticoagulation with LMWH (vs. DOAC) on discharge (adjusted odds ratio [aOR] =12.81, 95 % CI: 6.60-25.90).

While most patients diagnosed with VTE in the ED setting were discharged with DOACs, most cancer patients included in our study were treated with LMWH over DOACs, despite increasing evidence around the efficacy and safety of DOACs in most cancer patients. Further research is needed to understand longitudinal trends in anticoagulation.