Balancing the risks of stroke and upper gastrointestinal tract bleeding in older patients with atrial fibrillation

OBJECTIVE: To determine how factors that increase the risk of major upper gastrointestinal (GI) tract hemorrhage (recent upper GI tract bleeding or concurrent use of nonsteroidal anti-inflammatory drugs) influence the choice of antithrombotic therapy in older patients (those > or = 65 years) with atrial fibrillation. METHODS: For older patients with atrial fibrillation and no other contraindications to antithrombotic therapy, a Markov decision-analytic model was used to determine the preferred treatment strategy (no antithrombotic therapy, long-term aspirin use, or long-term warfarin sodium use) based on their risk of major upper GI tract hemorrhage. Input data were obtained by a systematic review of MEDLINE. Outcomes were expressed as quality-adjusted life-years (QALYs). RESULTS: For 65-year-old patients with average risks of stroke and upper GI tract bleeding, warfarin therapy was associated with 12.1 QALYs per patient; aspirin therapy, 10.8 QALYs; and no antithrombotic therapy, 10.1 QALYs. For persons with significantly higher risks of upper GI tract bleeding and/or lower risks of stroke, warfarin was no longer clearly the optimal antithrombotic therapy (eg, for 80-year-old persons with a baseline risk of stroke of 4.3% per year who were concurrently taking a conventional nonsteroidal anti-inflammatory drug: warfarin, 7.44 QALYs; aspirin, 7.39 QALYs; and no treatment, 7.21 QALYs). CONCLUSIONS: For older patients with atrial fibrillation and factors that place them at a higher than average risk of upper GI tract bleeding, the optimal choice of antithrombotic therapy to prevent stroke can vary according to the magnitude of this risk. Based on the risks of stroke and upper GI tract bleeding, clinicians can use the treatment recommendations of this study to provide rational stroke prevention therapy for older patients with atrial fibrillation.