Venous thromboembolism management in Northeast Melbourne: how does it compare to international guidelines and data?

Abstract

Background: Venous thromboembolism (VTE) is a major cause of morbidity and mortality with significant heterogeneity in its management, both within our local practice and in international guidelines.

Aims: To provide a holistic evaluation of 'real-world' Australian experience in the warfarin era, including how we compare to international guidelines.

Methods: Retrospective evaluation of VTE from July 2011 to December 2012 at two major hospitals in Melbourne, Australia. These results were compared to recommendations in the international guidelines.

Results: A total of 752 episodes involving 742 patients was identified. Contrary to international guidelines, an unwarranted heritable thrombophilia screen was performed in 22.0% of patients, amounting to a cost of AU$29 000. The duration of anticoagulation was longer compared to international recommendations, although the overall recurrence (3.2/100 person-years) and clinically significant bleeding rates (2.4/100 person-years) were comparable to 'real-world' data. Unprovoked VTE (hazard ratio 2.06; P = 0.01) was a risk factor for recurrence, and there was no difference in recurrence between major VTE (proximal deep vein thrombosis (DVT) and/or pulmonary embolism) and isolated distal DVT (3.02 vs 3.94/100 person-years; P = 0.25). Fourteen patients were subsequently diagnosed with malignancy, and patients with recurrent VTE had increased risk of prospective cancer diagnosis (relative risk 6.68; P < 0.001).

Conclusions: While our 'real-world' VTE experience during the warfarin era largely correlates with international guidelines, there remains heterogeneity in the management strategies, including excessive thrombophilia screening and longer duration of anticoagulation. This audit highlights the need for national VTE guidelines, as well as prospective auditing of VTE management, in the direct oral anticoagulant era for future comparison.

Keywords: economics; haemorrhage; recurrence; thrombophilia; venous thromboembolism.