AUTHOR=Sabaté M. , Vidal X. , Ballarin E. , Rottenkolber M. , Schmiedl S. , Grave B. , Huerta C. , Martin-Merino E. , Montero D. , Leon-Muñoz L. M. , Gasse C. , Moore N. , Droz C. , Lassalle R. , Aakjær M. , Andersen M. , De Bruin M. L. , Souverein P. , Klungel O. H. , Gardarsdottir H. , Ibáñez L. 

TITLE=Adherence to Direct Oral Anticoagulants in Patients With Non-Valvular Atrial Fibrillation: A Cross-National Comparison in Six European Countries (2008–2015)

JOURNAL=Frontiers in Pharmacology

VOLUME=Volume 12 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2021.682890

DOI=10.3389/fphar.2021.682890

ISSN=1663-9812

ABSTRACT=Aims:  To describe and compare the adherence to different direct oral anticoagulants (DOACs) in 8 European databases representing 6 countries. 
Methods: Longitudinal drug utilization study of new users (≥18 years) of DOACs (dabigatran, rivaroxaban, apixaban) with a diagnosis of non-valvular atrial fibrillation (2008-2015). Adherence was examined by estimating persistence, switching and discontinuation rates at 12 months. Primary non-adherence was estimated in BIFAP and SIDIAP databases.
Results: The highest persistence rate was seen for apixaban in the CPRD database (81%) and the lowest for dabigatran in the Mondriaan database (22%). The switching rate for all DOACs ranged from 2.4% to 13.1% (Mondriaan and EGB databases respectively). Dabigatran had the highest switching rate from 5.0 % to 20.0% (Mondriaan and EGB databases, respectively). The discontinuation rate for all DOACs ranged from 16.0% to 63.9% (CPRD and Bavarian CD databases, respectively). Dabigatran had the highest rate of discontinuers, except in the Bavarian CD and AOK Nordwest databases, ranging from 23.2% to 64.6% (CPRD and Mondriaan databases, respectively). Combined primary non-adherence for examined DOACs was 11.1% in BIFAP and 14.0% in SIDIAP. There were differences in population coverage and in the type of drug data source among the databases. 
Conclusion: Despite the differences in the characteristics of the databases and in demographic, and baseline characteristics of the included population that could explain some of the observed discrepancies, we can observe a similar pattern throughtout the databases.  Apixaban was the DOAC with the highest persistence. Dabigatran had the highest proportion of discontinuers and switchers at 12 months in most databases.. (EMA/2015/27/PH).