Anticoagulation for stroke prevention in elderly patients with atrial fibrillation, including those with falls and/or early-stage dementia: A single-center, retrospective, observational study

Background: Anticoagulation for stroke prevention is underused in elderly patients with nonvalvular atrial fibrillation (AF). Those with falls and/or early dementia may be at particular risk for stroke and hemorrhage. Objective: The aim of this study was to determine the prescribing patterns, risks, and benefits of anticoagulation with warfarin or acetylsalicylic acid (ASA) in elderly patients with AF at risk for stroke and hemorrhage, including those with falls and/or dementia. Methods: In this single-center, retrospective, observational study, data from patients aged ≥65 years with chronic nonvalvular AF treated at an urban academic geriatrics practice over a 1-year period were included. Eligible patients were receiving noninvasive management of AF with warfarin or ASA. Data were assessed to determine the prevalences of stroke, hemorrhage, falls, and the possible effects of anticoagulation with dementia. Outcomes events at 12 months, including time-in-therapeutic range (TTR), stroke, hemorrhage, and death, were determined. The stroke risk in each patient was estimated using the CHADS₂ (congestive heart failure, hypertension, age ≥75 years, diabetes, history of stroke or transient ischemic attack) score, and the risk for hemorrhage was estimated using the Outpatient Bleeding Risk Index. Results: A total of 112 patients (mean age, 82 years) were identified; 106 were included in the present analysis (80 women, 26 men); 6 were not receiving antithrombotic therapy and thus were excluded from the analysis. Warfarin was prescribed in 85% (90 patients); ASA, 15% (16). International normalized ratio testing was done frequently, with a median interval of 13.7 days between tests (92% within 28 days). No association was found between an improved TTR and the number of tests per unit of time or the number of patients per clinician. The distributions of both the CHADS₂ and Outpatient Bleeding Risk Index scores were not significantly different between the warfarin and ASA groups. The proportions of patients treated with warfarin were not significantly different between the groups with a high risk for hemorrhage and the groups at lower risk. At 12 months in the 90 patients initially treated with warfarin, the rate of stroke was 2% (2 patients); major hemorrhage, 6% (5); and death, 20% (18). Mortality was greater in patients with falls (45% [5/11]) and/or dementia (47% [8/17]) compared with those without either falls or dementia (12% [8/65]). Conclusions: In this well-monitored geriatric population with chronic AF, including patients with falls and/or dementia, a high percentage were prescribed warfarin (85%), with low rates of stroke, hemorrhage, and death at 12 months despite a low TTR. Patients with falls and/or dementia had a high mortality rate (~45%).