Translating the Results of Randomized Trials into Clinical Practice: The Challenge of Warfarin Candidacy Among Hospitalized Elderly Patients With Atrial Fibrillation

Abstract

Background and Purpose— Numerous studies have documented under use of warfarin particularly among elderly patients. A better understanding of the discrepancy between trials and clinical practice will help inform stroke prevention strategies in this vulnerable age group. The study objective was to prospectively assess the use of antithrombotic therapy among a contemporary cohort of patients with atrial fibrillation at the time of hospital discharge. In addition to baseline characteristics, we sought to define the physician-cited reason for not prescribing warfarin for each patient. Methods— Patients with atrial fibrillation were prospectively identified and followed to hospital discharge. Enrolled patients were ≥65 years of age, not taking warfarin on admission, and had their longitudinal care provided at our institution. Predictors of warfarin use were determined and physician-cited contraindications were compared across age groups. Results— Fifty-one percent (n=206) of patients were discharged on warfarin: 75% of those 65 to 69 years of age, 59% 70 to 79, 45% 80 to 89, and 24% age ≥90 years. Of the remaining 199 patients, 83% had ≥2 major risk factors for stroke, and 98% were felt to have contraindications including nearly 25% who were unable to tolerate warfarin in the past. Among patients age ≥80, falling was the most often physician-cited reason for not prescribing warfarin (41%) followed by hemorrhage (28%). Conclusion— Our findings suggest that many elderly patients at high risk for stroke may not be optimal candidates for anticoagulant therapy. There is a pressing need for alternative stroke prevention strategies for this expanding patient population.