July 28, 2017Pharmacoepidemiology and Drug Safety68 citationsOpen Access
Adherence with direct oral anticoagulants in nonvalvular atrial fibrillation new users and associated factors: a French nationwide cohort study
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Key Result
One-year adherence to direct oral anticoagulants was poor in new users with nonvalvular atrial fibrillation, at 53.3% for dabigatran and 59.9% for rivaroxaban.
Key Points
- This study aims to evaluate one-year adherence rates to direct oral anticoagulants among new users with nonvalvular atrial fibrillation and identify factors influencing nonadherence.
- Cohort study of OAC-naive nv-AF patients initiating dabigatran or rivaroxaban using nationwide French health data.
- One-year adherence defined by proportion of days covered of 80% or more since treatment initiation.
- Multivariate logistic regression assessed associations between nonadherence and baseline patient characteristics.
- One-year adherence rates were 53.3% for dabigatran users and 59.9% for rivaroxaban users.
- In patients who did not die or switch, adherence was higher at 69.6% for dabigatran and 72.3% for rivaroxaban.
- Having concomitant ischemic heart disease significantly increased the risk of nonadherence in both cohorts.
Study Design
Type
Cohort (n=22,267)
Multicenter
Yes
Structured PICO
P
Population
22,267 OAC-naive patients with nonvalvular atrial fibrillation initiating dabigatran or rivaroxaban, followed for 1 year to assess adherence.
E
Exposure
Direct oral anticoagulants (dabigatran or rivaroxaban)
O
Outcome
1-year adherence defined by the proportion of days covered (PDC) of 80% or more over a fixed 1-year period after treatment initiation
In real-world practice, 1-year adherence to DOACs (dabigatran and rivaroxaban) in new users with nonvalvular atrial fibrillation is poor, highlighting an ongoing challenge in AF management.
Main Result
Absolute Event Rate: 53.3% vs 59.9%
Abstract
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.