Economic factors associated with antithrombotic treatments for stroke prevention in patients with atrial fibrillation
1AstraZeneca, HEOR/Medical Science, Parklands FE2 D/4, Alderley Park SK10 4TG, UK
2University of York, Heslington, UK
3AstraZeneca, Mölndal, Sweden
4Western Infirmary, Glasgow, UK
* Corresponding author. Tel: +44 1625 519944; fax: +44 1625 518537. E-mail address: paul.miller3{at}astrazeneca.com
Our objective is to summarize the key components of a health economic evaluation of antithrombotic treatments for stroke prevention in patients with atrial fibrillation (AF). The key drivers are the changes in cost and quality of life associated with: thromboembolic events; the antithrombotic drug and its management; and bleeding events. Data on costs and utilities associated with all three components are presented. In clinical trials, vitamin K antagonists (VKAs, e.g. warfarin) substantially reduce the risk of stroke in patients with AF. However, the high cost of stroke makes clinical effectiveness a key element in the economic evaluation of stroke prevention interventions. Clinical effectiveness is lower than efficacy in clinical trials because of the variable anticoagulant effect and significant underuse of VKA therapy. The pure cost implication of reduced clinical effectiveness is illustrated using published data to extrapolate from clinical trials to clinical practice. If VKA effectiveness equivalent to that seen in trials could be achieved, 13.79 strokes per 100 patients over 5 years could be avoided compared with the typical current treatment pattern. If we take the lifetime cost of stroke to be
126 797 (based on a USA estimate), preventing these additional strokes will trigger lifetime cost savings of
1.75 million. Health economic decision-making must balance these gains against the cost of drug and management of VKA therapy.
Key Words: Anticoagulants Arrhythmia Stroke Prevention Health economic analysis