Characteristics of patients receiving extended treatment after incident venous thromboembolism

Given high recurrence risk after venous thromboembolism (VTE), guidelines recommend extended dose rivaroxaban (10 mg OD) or apixaban (2.5 mg BID) to be considered after 6 months of initial treatment. This study aimed to provide insight into clinical practice regarding the use of extended preventive treatment and to describe duration of the initial treatment. Linkage of nationwide health registers identified all in- and outpatients with VTE from April 2017 through 2018. Hazard ratios (HR) with 95% confidence intervals (CIs) were calculated adjusting for other VTE-related factors. The study included 6030 patients with VTE. Among rivaroxaban users, 2.2% (n = 113) received the extended 10-mg dose after mean 9.4 (SD 3.1) months of standard treatment. For apixaban, 4.7% (n = 40) received extended 2.5-mg dose after mean 8.0 months (SD 3.9). After adjustments, incident pulmonary embolism (HR 1.81 95% CI 1.12;2.91) and trauma/fracture (HR 1.42 95% CI 0.46;4.43) were associated with switching to extended dose, whereas patients with unprovoked VTE were less likely to receive the extended dose (HR 0.68 95% CI 0.30;1.55). Less than 3% of patients with incident VTE received extended treatment after initial standard treatment. Even though international guidelines suggest that the risk-benefit balance is in favour of extended VTE treatment, this was yet to be translated into clinical practice as of 2018. Studies using contemporary data are warranted to investigate routine clinical practice of extended treatment for VTE recurrence.