Remarks: Patients who place an exceptionally high value on stroke reduction and a low value on avoid- ing bleeding and the burden associated with anti- thrombotic therapy are likely to choose antithrombotic therapy rather than no antithrombotic therapy. Other factors that may in uence the choices above are a consideration of patient-speci c bleeding risk and the presence of additional risk factors for stroke, including age 65 to 74 years and female sex, which have been more consistently validated, and vascu- lar disease, which has been less well validated (see section 2.1.12). The presence of multiple non- CHADS2 risk factors for stroke may favor oral anti- coagulation therapy. 2.1.9 Recommendations for Patients With AF at Intermediate Risk of Stroke (eg, CHADS2 Score of 1): For patients at intermediate risk of stroke with a CHADS2 score of 1, compared with no therapy, 1 year of VKA therapy is expected to result in 15 fewer deaths and 15 fewer nonfatal strokes per 1,000 patients at the cost of eight more nonfatal major extracranial bleeds (Table 3). Regarding the choice between VKA therapy and aspirin, VKA therapy is anticipated to prevent nine nonfatal strokes for every 1,000 patients treated for 1 year compared with aspirin but will result in three additional bleeds and www.chestpubs.org CHEST / 141 / 2 / FEBRUARY, 2012 SUPPLEMENT e557S stroke (eg, CHADS2 score 2), we recommend oral anticoagulation rather than no therapy (Grade 1A), aspirin (75 mg to 325 mg once daily) (Grade 1B), or combination therapy with aspirin and clopidogrel (Grade 1B). For patients who are unsuitable for or choose not to take an oral anticoagulant (for reasons other than concerns about major bleeding), we recommend combi- nation therapy with aspirin and clopidogrel rather than aspirin (75 mg to 325 mg once daily) (Grade 1B). 