title: Clopidogrel and aspirin versus aspirin alone for the prevention of stroke in patients with a history of atrial fibrillation: subgroup analysis of the CHARISMA randomized trial.
abstract: BACKGROUND
  Aspirin offers modest reduction in stroke in patients with atrial fibrillation. Whether combination of aspirin with clopidogrel offers additional protection is unclear.
  
  
  METHODS
  Post-hoc subgroup analysis of 593 participants with a history of atrial fibrillation in the Clopidogrel for High Atherothrombotic Risk and Ischemic Stabilization, Management, and Avoidance (CHARISMA) randomized trial testing clopidogrel 75 mg per day plus aspirin (75-162 mg per day) vs. aspirin alone in patients with stable cardiovascular disease or multiple cardiovascular risk factors.
  
  
  RESULTS
  Mean patient age was 70 years, 78% were men, and hypertension, heart failure and diabetes were present in 78, 20 and 44%, respectively. During a median follow-up of 2.3 years, stroke (ischemic and hemorrhagic) occurred in 15 of 298 assigned to clopidogrel plus aspirin and in 14 of 285 given aspirin alone (hazard ratio, HR, 1.03, 95% CI 0.49-2.1). There was no difference in all-cause mortality (HR 1.1, 95% CI 0.6-1.9) or in the composite of stroke, myocardial infarction, or vascular death (HR = 1.2, 95% CI 0.7-2.0). Severe/fatal extracranial hemorrhage occurred in 6 patients with combination vs. 3 with aspirin alone.
  
  
  CONCLUSIONS
  This post-hoc subgroup analysis does not support the use of this combination over aspirin alone in patients with a history of atrial fibrillation pending results of ongoing larger randomized trials.
authors.affiliation: Department of Neurology, University of Texas Health Science Center, San Antonio, TX 78229-3900, USA. hartr@uthscsa.edu
authors.forename: Robert G
authors.initials: RG
authors.lastname: Hart
authors.forename: Deepak L
authors.initials: DL
authors.lastname: Bhatt
authors.forename: Werner
authors.initials: W
authors.lastname: Hacke
authors.forename: Keith A A
authors.initials: KA
authors.lastname: Fox
authors.forename: Graeme J
authors.initials: GJ
authors.lastname: Hankey
authors.forename: Peter B
authors.initials: PB
authors.lastname: Berger
authors.forename: Tingfei
authors.initials: T
authors.lastname: Hu
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Topol
mesh_terms: D000368:Aged; D001241:Aspirin / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000150:complications*; D000077144:Clopidogrel; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D012307:Risk Factors; D020521:Stroke / Q000209:etiology / Q000517:prevention & control*; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D016896:Treatment Outcome
chemical_list: D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; D013988:Ticlopidine; D001241:Aspirin