title: Amino terminal pro-B-type natriuretic peptide, secondary stroke prevention, and choice of antithrombotic therapy.
abstract: OBJECTIVE
  Because of its association with atrial fibrillation and heart failure, we hypothesized that amino terminal pro-B-type natriuretic peptide (NT-proBNP) would identify a subgroup of patients from the Warfarin-Aspirin Recurrent Stroke Study, diagnosed with inferred noncardioembolic ischemic strokes, where anticoagulation would be more effective than antiplatelet agents in reducing risk of subsequent events.
  
  
  METHODS
  NT-proBNP was measured in stored serum collected at baseline from participants enrolled in Warfarin-Aspirin Recurrent Stroke Study, a previously reported randomized trial. Relative effectiveness of warfarin and aspirin in preventing recurrent ischemic stroke or death over 2 years was compared based on NT-proBNP concentrations.
  
  
  RESULTS
  About 95% of 1028 patients with assays had NT-proBNP below 750 pg/mL, and among them, no evidence for treatment effect modification was evident. For 49 patients with NT-proBNP >750 pg/mL, the 2-year rate of events per 100 person-years was 45.9 for the aspirin group and 16.6 for the warfarin group, whereas for 979 patients with NT-proBNP ≤750 pg/mL, rates were similar for both treatments. For those with NT-proBNP >750 pg/mL, the hazard ratio was 0.30 (95% confidence interval: 0.12-0.84; P=0.021) significantly favoring warfarin over aspirin. A formal test for interaction of NT-proBNP with treatment was significant (P=0.01).
  
  
  CONCLUSIONS
  For secondary stroke prevention, elevated NT-proBNP concentrations may identify a subgroup of ischemic stroke patients without known atrial fibrillation, about 5% based on the current study, who may benefit more from anticoagulants than antiplatelet agents.  Clinical Trial Registration- This trial was not registered because enrollment began before 2005.
authors: Department of Neurology, Harborview Medical Center, Seattle, WA, USA. wl@uw.edu
authors: W T
authors: WT
authors: Longstreth
authors: Richard A
authors: RA
authors: Kronmal
authors: John L P
authors: JL
authors: Thompson
authors: Robert H
authors: RH
authors: Christenson
authors: Steven R
authors: SR
authors: Levine
authors: Rebecca
authors: R
authors: Gross
authors: Robin L
authors: RL
authors: Brey
authors: Richard
authors: R
authors: Buchsbaum
authors: Mitchell S V
authors: MS
authors: Elkind
authors: David L
authors: DL
authors: Tirschwell
authors: Stephen L
authors: SL
authors: Seliger
authors: J P
authors: JP
authors: Mohr
authors: Christopher R
authors: CR
authors: deFilippi
mesh_terms: D000368:Aged; D000925:Anticoagulants / Q000627:therapeutic use; D001241:Aspirin / Q000627:therapeutic use*; D015415:Biomarkers / Q000097:blood; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use; D055502:Secondary Prevention; D020521:Stroke / Q000097:blood / Q000517:prevention & control*; D016896:Treatment Outcome; D014859:Warfarin / Q000627:therapeutic use*
chemical_list: D000925:Anticoagulants; D015415:Biomarkers; D010446:Peptide Fragments; D010975:Platelet Aggregation Inhibitors; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain; D014859:Warfarin; D001241:Aspirin