Comparative non-persistence in the first year of treatment with oral anticoagulants in patients with atrial fibrillation: A French comprehensive nationwide study.

BACKGROUND: Direct oral anticoagulants (DOACs) were developed as an alternative to vitamin K antagonists (VKAs) and are commonly used for stroke prevention in patients with non-valvular atrial fibrillation (NVAF). Unlike VKAs, DOACs do not require Internal Normalized Ratio (INR) monitoring, but regular intake is as important for effective anticoagulation. OBJECTIVES: This study examined treatment persistence among patients receiving oral anticoagulants (OACs) for NVAF. METHODS: Within the French healthcare claims database (SNDS), we assessed and compared the rates of non-persistence (≥ 30-day treatment gap) among patients with NVAF initiating an OAC between January 2014 and December 2016. The time-to-event of non-persistence was computed and plotted using a cumulative incidence function accounting for the competing risk of mortality. After adjusting on confounding factors, the risk for non-persistence was compared between apixaban and each other OACs using a Cox proportional hazard model, or Fine and Gray models. RESULTS: In a cohort of 321,501 OAC-naive patients with NVAF, the cumulative incidence of non-persistence at 12 months considering competing risk was 44.3%, 31.0%, 41.3% and 46.8% for VKAs, apixaban, rivaroxaban and dabigatran, respectively. Median therapy duration before non-persistence ranged between 70 and 121 days. Non-persistence was lower with apixaban compared with VKAs (HR=0.63, 95%CI=[0.62-0.64]), rivaroxaban (HR=0.71, 95%CI=[0.70-0.73]), and dabigatran (HR=0.60, 95%CI=[0.59-0.62]). CONCLUSIONS: In this nationwide observational study, non-persistence rates of oral anticoagulant treatment were high in patients treated for NVAF. Apixaban-treated patients seem to experience lowest discontinuation rates 12 months after treatment initiation compared to patients treated with any other OAC.

Comparative Safety and Effectiveness of Oral Anticoagulants in Nonvalvular Atrial Fibrillation: The NAXOS Study.

BACKGROUND AND PURPOSE: The effects of direct oral anticoagulants in nonvalvular atrial fibrillation should be assessed in actual conditions of use. France has near-universal healthcare coverage with a unified healthcare information system, allowing large population-based analyses. NAXOS (Evaluation of Apixaban in Stroke and Systemic Embolism Prevention in Patients With Nonvalvular Atrial Fibrillation) aimed to compare the safety, effectiveness, and mortality of apixaban with vitamin K antagonists (VKAs), rivaroxaban, and dabigatran, in oral anticoagulant-naive patients with nonvalvular atrial fibrillation. METHODS: This was an observational study using French National Health System claims data and including all adults with nonvalvular atrial fibrillation who initiated oral anticoagulant between 2014 and 2016. Outcomes of interest were major bleeding events leading to hospitalization (safety), stroke and systemic thromboembolic events (effectiveness), and all-cause mortality. Four approaches were used for comparative analyses: matching on propensity score (PS; 1:n); as a sensitivity analysis, matching on high-dimensional PS; adjustment on PS; and adjustment on known confounders. For each outcome, cumulative incidence rates accounting for competing risks of death were estimated. RESULTS: Overall, 321 501 patients were analyzed, of whom 35.0%, 27.2%, 31.1%, and 6.6% initiated VKAs, apixaban, rivaroxaban, and dabigatran, respectively. Apixaban was associated with a lower PS-matched risk of major bleeding compared with VKAs (hazard ratio [HR], 0.43 [95% CI, 0.40-0.46]) and rivaroxaban (HR, 0.67 [95% CI, 0.63-0.72]), but not dabigatran (HR, 0.93 [95% CI, 0.81-1.08]). Apixaban was associated with a lower risk of stroke and systemic thromboembolic event compared with VKAs (HR, 0.60 [95% CI, 0.56-0.65]), but not rivaroxaban (HR, 1.05 [95% CI, 0.97-1.15]) or dabigatran (HR, 0.93 [95% CI, 0.78-1.11]). All-cause mortality was lower with apixaban than with VKAs, but not lower than with rivaroxaban or dabigatran. CONCLUSIONS: Apixaban was associated with superior safety, effectiveness, and lower mortality than VKAs; with superior safety than rivaroxaban and similar safety to dabigatran; and with similar effectiveness when compared with rivaroxaban or dabigatran. These observational data suggest potentially important differences in outcomes between direct oral anticoagulants, which should be explored in randomized trials.