title: Aspirin resistance in secondary stroke prevention.
abstract: BACKGROUND
  We investigated the platelet function in stroke patients treated with aspirin [acetylsalicylic acid (ASA)] for secondary stroke prevention during a follow-up period of 1 year.
  
  
  METHODS
  In this prospective study 291 patients with first initiated aspirin therapy (300 mg/day) for secondary stroke prevention were included. Platelet aggregation measurements were performed 24 h, 3, 6, and 12 months after starting medication.
  
  
  RESULTS
  Twenty-one of 291 patients (7.2%) were identified as primary ASA-non-responders (initial insufficient platelet inhibition) and 4.1% as secondary ASA-non-responders (insufficient platelet inhibition during follow-up). There were no significant differences between ASA-responders and ASA-non-responders concerning age, gender, risk factors, and stroke characteristics.
  
  
  CONCLUSIONS
  Aspirin resistance in stroke patients is not uncommon. The clinical usefulness of routine platelet function tests needs to be proved by further trials.
authors.affiliation: Department of Neurology, Municipal Hospital Altenburg, Altenburg, Germany. berrouschot.kkh-altenburg@t-online.de
authors.forename: J
authors.initials: J
authors.lastname: Berrouschot
authors.forename: B
authors.initials: B
authors.lastname: Schwetlick
authors.forename: G
authors.initials: G
authors.lastname: von Twickel
authors.forename: C
authors.initials: C
authors.lastname: Fischer
authors.forename: H
authors.initials: H
authors.lastname: Uhlemann
authors.forename: T
authors.initials: T
authors.lastname: Siegemund
authors.forename: A
authors.initials: A
authors.lastname: Siegemund
authors.forename: A
authors.initials: A
authors.lastname: Roessler
mesh_terms: D000368:Aged; D001241:Aspirin / Q000008:administration & dosage* / Q000009:adverse effects; D004351:Drug Resistance; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D010974:Platelet Aggregation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage* / Q000009:adverse effects; D011446:Prospective Studies; D055502:Secondary Prevention; D020521:Stroke / Q000188:drug therapy / Q000517:prevention & control*
chemical_list: D010975:Platelet Aggregation Inhibitors; D001241:Aspirin