Ischaemic stroke and bleeding rates in ‘real-world’ atrial fibrillation patients

Isla M. Ogilvie; Sharon A. Welner; Warren Cowell; Gregory Y. H. Lip

doi:10.1160/TH10-10-0674

Thrombosis and Haemostasis, Table of Contents

Thromb Haemost 2011; 106(01): 34-44
DOI: 10.1160/TH10-10-0674

Review Article

Schattauer GmbH

Ischaemic stroke and bleeding rates in ‘real-world’ atrial fibrillation patients

Authors

Isla M. Ogilvie

¹BioMedCom Consultants inc., Montréal, Canada
Sharon A. Welner

¹BioMedCom Consultants inc., Montréal, Canada
Warren Cowell

²Global Health Economics and Reimbursement, Bayer HealthCare, Uxbridge, UK
Gregory Y. H. Lip

³University of Birmingham Centre for Cardiovascular Sciences, City Hospital, Birmingham, UK

Abstract

Summary

Stroke prevention guidelines recommend oral anticoagulants (OAC) for atrial fibrillation (AF) patients at moderate/high risk of stroke, and antiplatelet or no therapy for those at low/moderate risk. Outcomes for AF patients receiving antiplatelet/no therapy in ‘real-life’ clinical practice were explored. This study compared clinical event rates (stroke/bleeding) for AF patients treated with OAC therapy, antiplatelets or no therapy in usual clinical practice to event rates in OAC-treated AF patients from optimally-monitored ‘real-life’ settings (anticoagulation clinics). We searched biomedical literature (1994–2010) using PubMed to identify ‘real-world’ studies of clinical event rates for AF patients receiving OAC therapy, antiplatelets, or no therapy; event rates were extracted for each treatment and setting. We identified 136 studies of thromboembolic events and 86 of bleeding events. Ischaemic stroke rates (30 studies) were higher for AF patients receiving no therapy (median: 4.45/100 person-years; range: 0.25–5.9) or antiplatelet-therapy (median: 4.45/100 person-years; range: 2.0–10) compared to OACtreated patients monitored in anticoagulation clinics (median: 1.72/100 person-years; range: 0.97–2.00), or from a non-specialized setting (median 1.66/100 person-years; range: 0–4.9). Major bleeding rates (32 studies) for patients receiving antiplatelet/no therapy were similar to OAC-treated patients from both clinical settings. As in randomised clinical trials, AF patients in ‘real-world’ clinical practice receiving antiplatelet/no therapy have higher rates of ischaemic stroke than OAC-treated patients. Antiplatelet/no therapy was associated with similar bleeding rates to OAC therapy. Increasing utilisation of anticoagulants in clinical practice could improve patient outcomes.

Keywords

Atrial fibrillation - oral anticoagulation - antiplatelets - stroke - bleeding

Full Text

References

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