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Thromb Haemost 2014; 111(05): 798-807
DOI: 10.1160/TH13-11-0918
Theme Issue Article
Schattauer GmbH

New oral anticoagulants for stroke prevention in atrial fibrillation: impact of study design, double counting and unexpected findings on interpretation of study results and conclusions

Noel C. Chan
1   Population Health Research Institute, Hamilton, Canada
3   Thrombosis and Atherosclerosis Research Institute, Hamilton, Canada
,
Jeremy S. Paikin
2   Department of Medicine, McMaster University, Hamilton, Canada
,
Jack Hirsh
2   Department of Medicine, McMaster University, Hamilton, Canada
3   Thrombosis and Atherosclerosis Research Institute, Hamilton, Canada
,
Mandy N. Lauw
1   Population Health Research Institute, Hamilton, Canada
3   Thrombosis and Atherosclerosis Research Institute, Hamilton, Canada
4   Department of Vascular Medicine, Academic Medical Center, Amsterdam, The Netherlands
,
John W. Eikelboom
1   Population Health Research Institute, Hamilton, Canada
2   Department of Medicine, McMaster University, Hamilton, Canada
3   Thrombosis and Atherosclerosis Research Institute, Hamilton, Canada
,
Jeffrey S. Ginsberg
2   Department of Medicine, McMaster University, Hamilton, Canada
3   Thrombosis and Atherosclerosis Research Institute, Hamilton, Canada
› Author Affiliations
Further Information

Publication History

Received: 07 November 2013

Accepted after minor revision: 29 January 2014

Publication Date:
01 December 2017 (online)

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Summary

Four recently introduced new oral anticoagulants (dabigatran, rivaroxaban, apixaban and edoxaban) have been shown to be at least as efficacious and safe as warfarin for stroke prevention in patients with atrial fibrillation in their respective trials. The first three have been approved, while edoxaban is awaiting regulatory approval. Several guidelines have endorsed the approved new oral anticoagulants over warfarin because of their favourable risk-benefit ratio, low propensity for food and drug interactions, and lack of requirement for routine coagulation monitoring. In this invited review, we summarise the results of the four studies and discuss widely held conclusions. We take a step further and discuss how differences in study design, analysis plan, and unexpected events affect the interpretation of the study results. Finally, we take our re-interpretation of study results and discuss how they might impact clinical practice and anticoagulant choice for patients.

Keywords

Clinical trials - oral anticoagulants - stroke / prevention - thrombosis
 

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