PB0465 - Trends in anticoagulant treatment duration and outcomes after pulmonary embolism between 2014 and 2019: a nationwide cohort study

Background: Pulmonary embolism (PE) is treated with anticoagulants for at least three months. Thereafter, based on risk of recurrence and bleeding, some patients may benefit from indefinite anticoagulation. In the last decade guidelines have changed recommendations regarding indefinite treatment, which nowadays should be considered for patients with a first unprovoked PE. However, it is unclear whether prescription patterns and thereby outcomes have in fact changed during this period in line with these recommendations.

Aims: Describing time trends in the duration of anticoagulant treatment and outcomes after a first PE in the Netherlands between 2014 and 2019.

Methods: Patients with a first PE diagnosis were included using data from Statistics Netherlands. Patients who died or experienced recurrent PE within three months were excluded. We assessed prescriptions of anticoagulants within and beyond three months. Incidence rates (IRs) of major bleeding and recurrent VTE within 3-9 months after the PE were calculated.

Results: 49.904 patients (mean age 64.2 years, 49.6% male) had a first PE, of whom 22.3% had a malignancy. From 2014 to 2019 the use of vitamin K antagonists (VKA) within the first three months decreased from 77.4% to 9.1% whereas the use of DOACs increased from 1.2% to 76.1% of patients. The proportion of patients with ≥2 anticoagulant prescriptions between 3-9 months, indicating prolonged anticoagulation, increased from 61.4% (2014) to 67.9% (2019) (figure 1), which proportions were 59.8% to 66.9% for patients without malignancy, respectively. IRs of major bleeding within 3-9 months remained stable (2.18 to 2.17/100 person-years), whereas IRs of recurrent VTE decreased from 3.60 to 1.41/100 person-years (adjusted hazard ratio 0.38; 95% confidence interval 0.28–0.52) (figure 2).

Conclusion(s): Between 2014 and 2019 the use of prolonged anticoagulation after a first PE increased. Meanwhile, the incidence of major bleeding remained stable, whereas the incidence of recurrent VTE within 3-9 months decreased.