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Warfarin therapy in elderly patients. Factors determining efficiency and safety of long-term therapy

Kropacheva E. S.
Federal State Budgetary Institution, “Russian Cardiology Research and Production Complex” of the RF Ministry of Health Care, 3rd Cherepkovskaya 15a, Moscow 121552

Keywords: anticoagulants, safety, warfarin, elderly age, efficiency

DOI: 10.18087/rhfj.2012.3.1668

Relevance. The major reasons for not prescribing oral anticoagulants (OAC) in eligible senior patients with atrial fibrillation (AF) is the risk of bleeding, the danger of which, are often overestimated. Objective. To compare the effectiveness and safety of long-term therapy by Warfarin in patients younger and older than 70 with non-valvular AF. Materials and methods. We investigated antithrombotic treatment with Warfarin in 180 consecutive patients at the age from 32 to 78 with non-valvular AF. The selection of patients might be related to the high risk stroke category– the average grade by CHADS2 scale made 1.8±1.3. When evaluating by the CHA2DS2VASc scale the average grade made 2.9±1.1. Risk of bleedings was assessed by the HASBLEED scale. The duration of observation was 5 years. Results. Patients with с AF older 70 years as compared to younger patients had higher risk of thromboembolic complications and bleeding. Frequency of primary stroke and TIA (transient ischemic attack) in patients taking Warfarin was 1.4 % per year and the frequency of repeated thromboembolias in patients with ischemic stroke or TIA in anamnesis was 3.3 % per year. The frequency of fatal and non-fatal stroke was reliably higher in the group of patients older than 70 years. The frequency of major hemorrhagic complications didn’t differ between groups of patients older and younger than 70 and made 1.14 and 1.17 % per year, respectively. Conclusion. Patients older 70 years have elevated risk of stroke, but substantial quantity of eligible patients does not receive Warfarin. Development and implementation of the system of care for patients taking anticoagulants will allow increasing indication of Warfarin to patients requiring it and making the therapy safer.
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Kropacheva E. S. Warfarin therapy in elderly patients. Factors determining efficiency and safety of long-term therapy. Russian Heart Failure Journal. 2012;13(3):143-150

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