Background: Apixaban is a direct oral anticoagulant, which inhibits factor Xa. It has demonstrated clinical efficacy in prevention of stroke and systemic embolism in adult patients with nonvalvular atrial fibrillation and a better safety profile compared to warfarin.
Objectives: (1) To describe the characteristics of patients with nonvalvular atrial fibrillation beginning treatment with apixaban, (2) to analyze concomitant prescriptions of medications that could potentially interact with apixaban, (3) to evaluate the level of appropriate usage according to the recommended dosage, and (4) to estimate the level of apixaban persistence among naive and non-naive patients.
Methods: Cohort study using data from primary care (System for Research in Primary Care database, users of the Institut Català de la Salut; Catalonia, Spain) from August 2013 to December 2015.
Results: Mean age for apixaban-treated patients was 71.8 years (standard deviation = 11.1) and 55.6% were male. In all, 3.2% of patients receiving apixaban were taking drugs described as potentially related to either pharmacokinetic or pharmacodynamic interactions. According to the summary of product characteristics, 81.1% of patients with a recommended dose of 2.5 mg twice daily and 51.8% with a recommended dose of 5 mg twice daily actually took this dose. After 1 year of follow-up, 62.6% of the apixaban users showed good adherence.
Conclusion: The prescribed dose of apixaban did not fully follow the recommended dose, particularly in patients who were treatment naive. Patients with a prior history of anticoagulant treatment were more likely to remain persistent to treatment with apixaban.
Keywords: anticoagulants; apixaban; drug use review; electronic health records; medication adherence.