title: Aspirin related gastrointestinal bleeders have an exaggerated bleeding time response due to aspirin use.
abstract: BACKGROUND
  Gastrointestinal bleeding is related to non-steroidal anti-inflammatory drug (NSAID) use, especially aspirin, but only a small subset of users bleed.
  
  
  OBJECTIVE
  To look for risk factors or mechanisms whereby aspirin may promote gastrointestinal bleeding.
  
  
  METHODS
  Sixty one patients with previous aspirin related upper gastrointestinal bleeding and 61 matched controls.
  
  
  METHODS
  Patients and controls were given 375 mg of aspirin and sequential skin bleeding time and blood aspirin levels were measured. Additional studies included platelet lumiaggregation, von Willebrand factor, Factor VIII, and coagulation studies.
  
  
  RESULTS
  Baseline skin bleeding time was similar in bleeders and controls, but bleeders had a more prolonged skin bleeding time after aspirin use. Hyper-response was more frequent in bleeders (30% v 9.3%; p < 0.01) and was associated with more than one previous separate bleeding event and a lower packed cell volume during the preceding bleeding episode. No differences were found in other factors studied. Logistic regression analysis identified prolonged skin bleeding time after aspirin use as an independent factor contributing to aspirin related gastrointestinal bleeding (RR = 5.4; 95% CI: 1.8 to 17.1).
  
  
  CONCLUSIONS
  30% of patients with a history of aspirin related gastrointestinal bleeding have an exaggerated prolongation of skin bleeding time in response to aspirin, which may be a risk factor for bleeding. This intrinsic defect or to subclinical von Willebrand disease or different aspirin metabolism.
authors.affiliation: Service of Gastroenterology, Hospital Clínico Universitario, Zaragoza, Spain.
authors.forename: A I
authors.initials: AI
authors.lastname: Lanas
authors.forename: M T
authors.initials: MT
authors.lastname: Arroyo
authors.forename: F
authors.initials: F
authors.lastname: Esteva
authors.forename: R
authors.initials: R
authors.lastname: Cornudella
authors.forename: B I
authors.initials: BI
authors.lastname: Hirschowitz
authors.forename: R
authors.initials: R
authors.lastname: Sáinz
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000009:adverse effects* / Q000097:blood; D001241:Aspirin / Q000009:adverse effects* / Q000097:blood; D001760:Bleeding Time; D001777:Blood Coagulation / Q000187:drug effects*; D005169:Factor VIII / Q000032:analysis; D005260:Female; D006471:Gastrointestinal Hemorrhage / Q000097:blood / Q000139:chemically induced*; D006400:Hematocrit; D006801:Humans; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D012307:Risk Factors; D012459:Salicylates / Q000097:blood; D020156:Salicylic Acid; D012907:Smoking / Q000009:adverse effects; D014841:von Willebrand Factor / Q000032:analysis
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D012459:Salicylates; D014841:von Willebrand Factor; D005169:Factor VIII; D020156:Salicylic Acid; D001241:Aspirin