Stroke prevention in atrial fibrillation: physicians' attitudes to anticoagulation in older people

The increased prevalence of atrial fibrillation (AF) in older people contributes to an increased risk of stroke. Although clear guidelines exist, there is considerable variation in physicians' approaches to the selection of patients appropriate for warfarin treatment as stroke prevention. We compared attitudes to the anticoagulation of elderly patients with AF, in a postal study of geriatricians and specialist physicians (general physicians with specialist interests in Cardiology, Gastroenterology, Diabetes and Endocrinology, Nephrology and Neurology). A structured questionnaire was mailed to all 108 consultant physicians and geriatricians in South East Wales. This explored their attitude to their patients' age and comorbidity when considering the benefits and risks of warfarin prophylaxis for AF. About 25/30 geriatricians (83%) and 43/78 specialist physicians (55%) responded; an overall response rate of 63%. About 94% of the respondents agreed that patients aged over 75 with atrial fibrillation were at a greater risk of stroke than younger patients. About 68% considered warfarin related bleeds more likely in this age group, despite which most thought that the benefits of warfarin outweighed the risks. In people aged above 75, only 13/25 (52%) geriatricians and 17/43 (40%) specialist physicians viewed lone AF (AF with no underlying risk factor) as an indication for anticoagulation. When considering the use of warfarin, geriatricians' appeared more likely to be influenced by coexisting problems such as disability, falls, cerebrovascular disease and limited life expectancy. Only a history of falls (96% geriatricians vs. 86% specialist physicians) and cerebrovascular disease (79% geriatricians vs. 51% specialist physicians) had a significant influence on prescribing practice (P<0.05, chi(2) test). There appears to be widespread uncertainty about the indications for warfarin as stroke prophylaxis, and ageist attitudes or a lack of conviction of benefit appear to be disadvantaging older people. Patients aged below 65 with lone AF who are at the lowest risk of embolic events are often considered for treatment, whilst the use of warfarin in 75-year-olds with lone AF who are at a moderately high risk of embolic events remains disappointing.