Adherence with direct oral anticoagulants in nonvalvular atrial fibrillation new users and associated factors: a French nationwide cohort study

PURPOSE: Direct oral anticoagulants (DOACs) have been promoted in patients with nonvalvular atrial fibrillation (nv‐AF) as a more convenient alternative to vitamin K antagonists. We estimated 1‐year dabigatran and rivaroxaban adherence rates in nv‐AF patients and assessed associations between baseline patient characteristics and nonadherence. METHODS: This cohort study included OAC‐naive nv‐AF patients with no contraindications to OAC, who initiated dabigatran and rivaroxaban, using nationwide data from French national health care databases. One‐year adherence was defined by the proportion of days covered of 80% or more over a fixed 1‐year period after treatment initiation. Associations between nonadherence and baseline patient characteristics were assessed using multivariate logistic regression models. RESULTS: The population was composed of 11 141 dabigatran (women: 48%; mean age: 74 ± 10.7 y; ≥80 y: 34.9%) and 11 126 rivaroxaban (46.5%; 74 ± 10.9 y; 34.8%) new users. One‐year adherence was 53.3% in dabigatran‐treated and 59.9% in rivaroxaban‐treated patients, consistent with numerous subgroup analyses. A switch to vitamin K antagonist was observed in 14.5% of dabigatran and 11.7% of rivaroxaban patients; 10.2% and 5.9% of patients switched to another DOAC, respectively; and 4.3% of patients died in the 2 cohorts. In patients who did not die or switch during the follow‐up, 1‐year adherence was 69.6% in dabigatran‐treated and 72.3% in rivaroxaban‐treated patients. Having concomitant ischemic heart diseases was associated with an increased risk of nonadherence in the 2 cohorts. CONCLUSION: In this real‐life study, 1‐year adherence to DOAC is poor in nv‐AF new users. Despite the introduction of DOAC, adherence to OACs may remain a significant challenge in AF patients.