Anticoagulant therapies for acute venous thromboembolism among a cohort of patients discharged from Canadian urban and rural hospitals

Objective: To determine anticoagulant therapy at hospital discharge for patients with acute venous thromboembolism (VTE) and secondarily, to describe factors affecting choice of therapy.

Design: A retrospective chart review.

Setting: Canadian hospitals in Edmonton, Alberta (n=4), Regina, Saskatchewan (n=2) and rural Alberta (n=3) from April 2014 to March 2015.

Participants: All patients discharged with an acute VTE were screened. Those with atypical clots, another indication for anticoagulation, pregnancy/breast feeding or lifespan <3 months were excluded.

Primary and secondary outcomes: Primarily, we identified the proportion of patients discharged from hospital with acute VTE that were prescribed either traditional therapy (parenteral anticoagulant±warfarin) or a direct oral anticoagulant (DOAC). Secondarily, management based on setting, therapy choice based on deep vein thrombosis (DVT) versus pulmonary embolism (PE), clot burden and renal function was compared. DOAC dosing was assessed (when prescribed), length of hospital stay based on therapy was compared and planned follow-up in the community was described.

Results: Among the 695 patients included, most were discharged following a diagnosis of PE (82.9%) on traditional therapy (parenteral anticoagulant±warfarin) (70.2%) with follow-up by either a family doctor (51.5%) or specialist/clinic (46.9%) postdischarge. Regional variation was most evident between urban and rural sites. Of those prescribed a DOAC (28.3%), the majority were dosed appropriately (85.8%). DOAC use did not differ between those with DVT and PE, was proportionately higher for less severe clots and declined with worsening renal function. Patients prescribed DOACs versus traditional therapy had a shorter length of stay (4 vs 7 days, respectively).

Conclusions: Uptake of DOAC therapy for acute VTE was modest and may have been influenced by the timing of the audit in relation to the approval of these agents for this indication. Future audits should occur to assess temporal changes and ongoing appropriateness of care delivery.