CC BY 4.0 · TH Open 2023; 07(02): e133-e142
DOI: 10.1055/a-2080-6171
Original Article

Geographical Variation in the Use of Oral Anticoagulation and Clinical Outcomes among Patients with Atrial Fibrillation in Denmark, Sweden, and Finland

1   Diagnostic Centre, Silkeborg Regional Hospital, Silkeborg, Denmark
2   Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
Olli Halminen
3   Department of Industrial Engineering and Management, Aalto University, Espoo, Finland
Mika Lehto
4   Department of Internal Medicine, Hospital District of Helsinki and Uusimaa, Lohja Hospital, Lohja, Finland
5   Heart and Lung Center, Helsinki University Hospital and University of Helsinki, Helsinki, Finland
K E. Juhani Airaksinen
6   Turku University Hospital, University of Turku, Turku, Finland
Tomas Andersson
7   Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
8   Division of Family Medicine and Primary Care, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Huddinge, Sweden
Martin Holzmann
9   Functional Area of Emergency Medicine, Karolinska University Hospital, Stockholm, Sweden
10   Department of Internal Medicine Solna, Karolinska Institutet, Stockholm, Sweden
Pia Cordsen
11   Danish Center for Clinical Health Services Research, Aalborg University, Aalborg, Denmark
Nicklas Vinter
1   Diagnostic Centre, Silkeborg Regional Hospital, Silkeborg, Denmark
2   Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
11   Danish Center for Clinical Health Services Research, Aalborg University, Aalborg, Denmark
11   Danish Center for Clinical Health Services Research, Aalborg University, Aalborg, Denmark
› Author Affiliations
Funding This work was supported by Bristol Myers Squibb and Pfizer through a grant from the ERISTA program. The ERISTA program had no influence on the conception of the study, writing of the protocol, data analyses, and interpretation or writing of the manuscript.


Background Geographical mapping of variations in the treatment and outcomes of a disease is a valuable tool for identifying inequity. We examined international and intranational variations in initiating oral anticoagulation (OAC) therapy and clinical outcomes among patients with atrial fibrillation (AF) in Nordic countries. We also tracked real-world trends in initiating OAC and the clinical outcomes.

Methods We conducted a registry-based multinational cohort study of OAC-naive patients with an incident hospital diagnosis of AF in Denmark (N = 61,345), Sweden (N = 124,120), and Finland (N = 59,855) and a CHA2DS2-VASc score of ≥1 in men and ≥2 in women between 2012 and 2017. Initiation of OAC therapy was defined as dispensing at least one prescription between 90 days before and 90 days after the AF diagnosis. Clinical outcomes included ischemic stroke, intracerebral hemorrhage, intracranial bleeding, other major bleeding, and all-cause mortality.

Results The proportion of patients initiating OAC therapy ranged from 67.7% (95% CI: 67.5–68.0) in Sweden to 69.6% (95% CI: 69.2–70.0) in Finland, with intranational variation. The 1-year risk of stroke varied from 1.9% (95% CI: 1.8–2.0) in Sweden and Finland to 2.3% (95% CI: 2.2–2.4) in Denmark, with intranational variation. The initiation of OAC therapy increased with a preference for direct oral anticoagulants over warfarin. The risk of ischemic stroke decreased with no increase in intracranial and intracerebral bleeding.

Conclusion We documented inter- and intranational variation in initiating OAC therapy and clinical outcomes across Nordic countries. Adherence to structured care of patients with AF could reduce future variation.

Availability of Data

Individual-level data cannot be shared publicly due to national legislation. Data from individual countries can be accessed through an application to the relevant public authorities. The authors did not have special access privileges to these data.

Authors' Contributions

Conception and design: L.F., N.V., S.P.J. Acquisition of data: S.P.J., M.H., P.W. Data analyses: P.C., O.H., T.A. Interpretation of data: all authors. Manuscript drafting: L.F., N.V., S.P.J., P.C. Manuscript revision: all authors. Approved the final version of the manuscript: all authors. Obtaining funding: S.P.J. Full access to all data in Denmark: P.C. Full access to all data in Sweden: T.A. Full access to all data in Finland: O.H. Responsible for all aspects of the study, reliability, and control of bias of the results presented: all authors.

Supplementary Material

Publication History

Received: 18 October 2022

Accepted: 19 April 2023

Accepted Manuscript online:
25 April 2023

Article published online:
06 June 2023

© 2023. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (

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