2055. Anticoagulant Use for Atrial Fibrillation in the Elderly
Stephan A Gaehde, MD, MPH, VA Boston Healthcare System and Boston University School of Medicine, MT Brophy, Massachusetts Veterans Epidemiology Research and Information Center (MAVERIC) and VA Boston Healthcare System and Boston University School of Medicine, KE Snyder, Massachusetts Veterans Epidemiology Research and Information Center (MAVERIC), C Ives, VA Boston Healthcare System, D Gagon, Massachusetts Veterans Epidemiology Research and Information Center (MAVERIC) and Boston University School of Public Health, LD Fiore, Massachusetts Veterans Epidemiology Research and Information Center (MAVERIC) and VA Boston Healthcare System and BUSM and BUSPH

Objectives: To determine the influence of advanced age on anticoagulant use in subjects with atrial fibrillation and to explore the extent to which risk factors for stroke and contraindications to anticoagulant therapy predict subsequent use.

Methods: In this retrospective cohort study 2,217 patients followed in the Boston VA Healthcare System with non-valvular atrial fibrillation were identified. Subjects were stratified for risk of CVA, contraindications to anticoagulation and exposure to warfarin. Administrative databases were use to identify subject’s age, anticoagulant use, and the presence of a diagnosis of atrial fibrillation, cerebrovascular accident, hypertension, diabetes mellitus, congestive heart failure, gastrointestinal or cerebral hemorrhage.

Results: Unadjusted analysis showed no difference in warfarin use between those older than 75 years and the younger subjects regardless of the presence (33.9% vs 35.7%, p=0.37) or absence (33.4% vs 34.7%, p=0.58) of contraindications to anticoagulant therapy. Multivariate modeling demonstrated a 14% reduction (95%CI 4-22%) in anticoagulant use with each advancing decade of life. Intracranial hemorrhage was a significant deterrent (OR 0.27 95%CI 0.06-0.85). A history of hypertension (OR 2.90, 95%CI 2.15-3.89), congestive heart failure (OR 1.70, 95%CI 1.41-2.04) and cerebrovascular accident (OR 1.54, 95%CI 1.25-1.89) were significant independent predictors for anticoagulant use.

Conclusions: Despite consensus guidelines to treat all atrial fibrillation patients greater than 75 years of age with anticoagulants, we found advancing age to be an independent deterrent to warfarin use. Better estimates of the risk/benefit ratio for oral anticoagulant therapy in older patients with atrial fibrillation are needed to optimize decision-making.