title: Aspirin resistance: focus on clinical endpoints.
abstract: BACKGROUND
  Via its antiplatelet effect, aspirin reduces the odds of an arterial thrombotic event in high-risk patients by approximately 25%. However, 10% to 20% of patients with an arterial thrombotic event who are treated with aspirin have a recurrent arterial thrombotic event during long-term follow-up. Nevertheless, the effectiveness of aspirin has been questioned by the emergence of the concept of aspirin resistance, which has been introduced as an explanation of the fact that a considerable proportion of patients treated with aspirin exhibit normal platelet function.
  
  
  OBJECTIVE
  We systematically reviewed all available evidence till March 2008 on prevalence of aspirin resistance and its association with clinical outcome. We also collected articles showing the possible way of treatment.
  
  
  CONCLUSIONS
  Analyzing the data of different laboratory methods aspirin resistance seems to be associated with poor clinical outcome, although currently no standardized or widely accepted definition of aspirin resistance exists. The widely used laboratory methods might not be comparable with each other; therefore, specific treatment recommendations for patients who exhibit high platelet reactivity during aspirin therapy or who have poor platelet inhibition by aspirin are not established.
authors.affiliation: Department of Neurology, University of Pecs, School of Medicine, Pecs, Hungary.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Pusch
authors.forename: Gergely
authors.initials: G
authors.lastname: Feher
authors.forename: Katalin
authors.initials: K
authors.lastname: Kotai
authors.forename: Antal
authors.initials: A
authors.lastname: Tibold
authors.forename: Beata
authors.initials: B
authors.lastname: Gasztonyi
authors.forename: Andrea
authors.initials: A
authors.lastname: Feher
authors.forename: Elod
authors.initials: E
authors.lastname: Papp
authors.forename: Geza
authors.initials: G
authors.lastname: Lupkovics
authors.forename: Laszlo
authors.initials: L
authors.lastname: Szapary
mesh_terms: D001241:Aspirin / Q000627:therapeutic use*; D001760:Bleeding Time / Q000592:standards; D002318:Cardiovascular Diseases / Q000097:blood / Q000188:drug therapy*; D004351:Drug Resistance; D019317:Evidence-Based Medicine; D006801:Humans; D010973:Platelet Adhesiveness / Q000187:drug effects*; D010974:Platelet Aggregation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D010979:Platelet Function Tests / Q000295:instrumentation / Q000379:methods / Q000592:standards*; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D009626:Terminology as Topic; D013928:Thromboxane A2 / Q000097:blood; D016896:Treatment Outcome
chemical_list: D010975:Platelet Aggregation Inhibitors; D013928:Thromboxane A2; D001241:Aspirin