ABSTRACT
BACKGROUND: The uptake rate of non-vitamin K oral anticoagulants (NOAC) for the treatment of non-valvular atrial fibrillation (AF) was far lower in the Netherlands (NL) compared to Belgium (BE). Also, patients on VKA in NL were treated with a higher target international normalized ratio (INR) range of 2.5 to 3.5. OBJECTIVES: To explore the effect of these differences on thromboembolism (TE) and bleeding. METHODS: Data from the GARFIELD-AF registry was used. Patients with new-onset AF and ≥1 investigator-determined risk factor for stroke were included between 2010 and 2016. Event rates from 2 years of follow-up were used. RESULTS: In NL and BE, 1186 and 1705 patients were included, respectively. Female sex (42.3% vs 42.2%), mean age (70.7 vs 71.3 years), CHA2 DS2 -VASc (3.1 vs 3.1), and HAS-BLED score (1.4 vs 1.5) were comparable between NL and BE. At diagnosis in NL vs BE, 72.1% vs 14.6% received vitamin K antagonists (VKA) and 17.8% vs 65.5% NOACs, varying greatly across cohorts. Mean INR was 2.9 (±1.0) and 2.4 (±1.0) in NL and BE, respectively. Event rates per 100 patient-years in NL and BE, respectively, of all-cause mortality (3.38 vs 3.90; hazard ratio [HR] 0.86, 95% confidence interval [CI] 0.65-1.15), ischemic stroke/TE (0.82 vs 0.72; HR 1.14, 95% CI 0.62-2.11), and major bleeding (2.06 vs 1.54; HR 1.33, 95% CI 0.89-1.99) did not differ significantly. CONCLUSIONS: In GARFIELD-AF, despite similar characteristics, patients on anticoagulants were treated differently in NL and BE. Although the rate of major bleeding was 33% higher in NL, variations in bleeding, mortality, and TE rates were not statistically significant.
Subject(s)
Atrial Fibrillation , Stroke , Administration, Oral , Aged , Anticoagulants/adverse effects , Atrial Fibrillation/complications , Atrial Fibrillation/diagnosis , Atrial Fibrillation/drug therapy , Belgium , Female , Humans , Netherlands , Registries , Risk Factors , Stroke/drug therapy , Stroke/etiology , Stroke/prevention & control , Vitamin K/therapeutic useABSTRACT
Background: AF, anticoagulation, NOACs, changing patterns of prescription. Methods: We describe baseline data and treatment patterns of patients recruited in Belgium in the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF). Recruitment began when novel oral anticoagulants (NOACs) were introduced and provides a unique picture of changing treatment patterns over time. 1713 patients with a new (≤6 weeks duration) diagnosis of non-valvular atrial fibrillation (NVAF) and at least one investigator-defined stroke risk factor were recruited between May 2012 and August 2016, and will be prospectively followed for at least 2 years. Results: Overall, anticoagulant use in Belgium was higher than in the rest of Europe: 80.1% of patients received an anticoagulant ± antiplatelet (AP) therapy (14.5% on vitamin K antagonists; 65.6% on NOAC), 10.7% AP therapy and 9.3% no antithrombotic therapy. Over time, we observed an increase in anticoagulant use and a decrease in AP use for stroke prevention. NOAC use in Belgium was the highest of Europe at the study start, with many countries catching up later. In high stroke risk patients (CHA2DS2-VASc ≥2), anticoagulants were used in 84.3%, leaving 15.7% unprotected. In low risk patients (CHA2DS2-VASc 0-1) anticoagulants were overused (58.7%). Factor Xa inhibitors were used more frequently than direct thrombin inhibitors. Conclusion: Guideline adherence on stroke prevention was higher in Belgium than in the rest of Europe, and increased over time. NOAC use in Belgium was the highest of Europe at the study start, with many countries catching up later. Possible reasons are discussed. Clinical Trial Registration: http://www.clinicaltrials.gov . Unique identifier: NCT01090362.
