Age as a Risk Factor for Stroke in Atrial Fibrillation Patients

The prevalence of atrial fibrillation (AF) is related to age and is projected to rise exponentially as the populationages and the prevalence of cardiovascular risk factors increases. The risk of ischemic stroke is significantly increasedin AF patients, and there is evidence of a graded increased risk of stroke associated with advancingage. Oral anticoagulation (OAC) is far more effective than antiplatelet agents at reducing stroke risk in patientswith AF. Therefore, increasing numbers of elderly patients are candidates for, and could benefit from, the use ofanticoagulants. However, elderly people with AF are less likely to receive OAC therapy. This is mainly due to concernsabout a higher risk of OAC-associated hemorrhage in the elderly population. Until recently, older patientswere under-represented in randomized controlled trials of OAC versus placebo or antiplatelet therapy, and thereforethe evidence base for the value of OAC in the elderly population was not known. However, analyses of theavailable trial data indicate that the expected net clinical benefit of warfarin therapy is highest among patientswith the highest untreated risk for stroke, which includes the oldest age category. An important caveat with warfarintreatment is maintenance of a therapeutic international normalized ratio, regardless of the age of the patient,where time in therapeutic range should be 65%. Therefore, age alone should not prevent prescription ofOAC in elderly patients, given an appropriate stroke and bleeding risk stratification. (J Am Coll Cardiol 2010;56:827–37) © 2010 by the American College of Cardiology Foundation