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Thromb Haemost 2010; 104(06): 1106-1115
DOI: 10.1160/TH10-10-0642
Blood Coagulation, Fibrinolysis and Cellular Haemostasis
Schattauer GmbH

Treatments for stroke prevention in atrial fibrillation: A network meta-analysis and indirect comparisons versus dabigatran etexilate

Neil S. Roskell
1   RTI Health Solutions, Williams House, Manchester Science Park, Lloyd Street North, Manchester, UK
,
Gregory Y. H. Lip
2   University of Birmingham, Centre for Cardiovascular Sciences, City Hospital, Birmingham, UK
,
Herbert Noack
3   Boehringer Ingelheim GmbH, Binger Strasse, Ingelheim am Rhein, Germany
,
Andreas Clemens
3   Boehringer Ingelheim GmbH, Binger Strasse, Ingelheim am Rhein, Germany
,
Jonathan M. Plumb
3   Boehringer Ingelheim GmbH, Binger Strasse, Ingelheim am Rhein, Germany
› Author Affiliations Financial support:This project was funded by Boehringer Ingelheim International GmbH (BI). BI is developing dabigatran etexilate (Pradaxa→) for stroke prevention in patients with atrial fibrillation. The authors meet criteria for authorship as recommended by the International Committee of Medical Journal Editors, and are fully responsible for all content and editorial decisions, and were involved at all stages of manuscript development.
Further Information

Publication History

Received: 11 October 2010

Accepted: 20 October 2010

Publication Date:
24 November 2017 (online)

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Summary

Patients with atrial fibrillation at moderate to high risk of stroke are not always anticoagulated despite a lack of contraindications to vitamin K antagonists (VKAs) like warfarin. These patients are treated with aspirin, aspirin-clopidogrel combination therapy or even receive no thromboprophylaxis. The oral direct thrombin inhibitor, dabigatran etexilate 150 mg BID and 110 mg BID, might represent an alternative for these patients; however, no head-to-head clinical trial data exist versus these alternative treatments. A network meta-analysis (NMA) was performed to indirectly compare dabigatran etexilate with antiplatelets and placebo. Compared with placebo, dabigatran etexilate 150 mg BID was estimated to significantly reduce the risk of any stroke (ischaemic and haemorrhagic) by 75% (relative risk [RR] 0.25; 95% confidence interval [CI] 0.12–0.51), ischaemic stroke by 77% (RR 0.23; 95% CI 0.14–0.38), systemic embolism by 83% (RR 0.17; 95% CI 0.05–0.50) and mortality by 36% (RR 0.64; 95% CI 0.45–0.91). Dabigatran etexilate 150 mg BID was estimated to significantly reduce the risk of any stroke compared with aspirin monotherapy by 63% (RR 0.37; 95% CI 0.20–0.69) and aspirin plus clopidogrel by 61% (RR 0.39; 95% CI 0.21–0.72). Trends toward reduced risk with both dabigatran etexilate regimens were found for most clinical outcomes. Relative risk estimates of dabigatran etexilate versus adjusted-dose VKAs within the NMA were consistent with results from the head-to-head randomised trial of these two strategies. Indirect evidence suggests treatment with dabigatran etexilate offers benefit for the prevention of stroke, systemic embolism and mortality over antiplatelets and placebo. There was no indication of increased intracranial or extracranial haemorrhage with dabigatran etexilate compared to antiplatelet agents.

Keywords

Anticoagulation - atrial fibrillation - dabigatran - meta-analysis - stroke - thrombosis

 

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