Bleeding and venous thromboembolism events in cancer patients taking direct oral anticoagulants vs. low molecular weight heparin

Introduction

Patients with cancer have an increased risk of developing venous thromboembolism (VTE), and subsequently a higher risk of bleeding secondary to anticoagulants. Low-molecular weight heparin (LMWH) has been the standard of care for these patients, with emerging data on the use of direct oral anticoagulants (DOACs). The primary objective of the study was to determine the prevalence of major bleeding events in cancer patients taking DOACs or LMWH for VTE. Secondary objectives included the rate of first VTE recurrence and the effect of concomitant antiplatelet agents and/or significant drug interactions on major bleeding or recurrent VTE.

Materials and methods

Using the electronic medical record at the University of Rochester Medical Center, we retrospectively identified adult patients with active malignancy who had a diagnosis of VTE requiring therapeutic anticoagulation within the study period of July 1st, 2015 to June 1st, 2019. Patients were excluded if they were receiving prophylactic doses of LMWH per the institution VTE guidelines. Data on anticoagulant medications were collected as well as information on major bleeding and recurrent VTE events.

Results and conclusions

There is insufficient evidence of difference in risk of major bleeding among patients who received a DOAC vs LMWH (cause-specific hazard ratio (HR) = 0.77, 95% CI 0.29–2.04, P = 0.60). There was also no evidence of a difference in risk of recurrent VTE between patients who received DOAC vs. LMWH (cause-specific HR = 0.98, 95% CI 0.15–6.26, P = 0.98). These results suggest that DOACs are not significantly less safe than LMWH for patients with cancer.