A recent study published in the journal Current Medical Research and Opinion suggests that 90-day and 180-day persistence in patients with venous thromboembolism (VTE) initially treated with vitamin K antagonist (VKA) have significantly increased between 2001 and 2013. Trends for persistence were significant for both first deep vein thrombosis (DVT) and first pulmonary embolism (PE). If increased persistence translates to decreasing risk for recurrent VTE needs further confirmation.
Researchers conducted a retrospective cohort study on 16,018 patients with first-ever VTE (DVT, 60.7%; PE, 39.3%), who were initiated on VKA within 30 days. The study population was identified from data derived from the UK Clinical Practice Research Datalink. VKA users were followed for the duration of oral anticoagulation which included switching to non-VKA oral anticoagulants. Probabilities for discontinuing oral anticoagulant treatment within 90 and 180 days were estimated.
Between 2001 and 2013, 90-day and 180-day persistence for remaining on oral anticoagulant treatment increased from 75.6% to 91.2% and 39.3% to 61.1%, respectively (both P<.0001). The median time until discontinuation increased from 4.8 to 7.2 months. Increased persistence on oral anticoagulants was significant for patients with DVT, PE, provoked/unprovoked VTE, provoked/unprovoked DVT and provoked/unprovoked PE. Persistence did not differ between patients with provoked/unprovoked VTE, but persistence was lower following DVT than PE (P<.0001).
Authors comment: “Clinical implementation of national and international guidelines together with the introduction of non-VKA oral anticoagulant into the market, and the growing experience of VKA use by physicians, may have contributed to the longer treatment duration observed.”
