title: High incidence of clopidogrel-associated gastrointestinal bleeding in patients with previous peptic ulcer disease.
abstract: BACKGROUND
  In average-risk patients, the new anti-platelet agent, clopidogrel, causes less upper gastrointestinal adverse events than aspirin. However, there are no safety data on the use of clopidogrel in high-risk patients.
  
  
  OBJECTIVE
  To evaluate the safety of clopidogrel in patients with peptic ulcer disease in a retrospective cohort longitudinal study.
  
  
  METHODS
  During the period from January 2000 to May 2002, 70 patients who were prescribed clopidogrel (75 mg/day) for a previous history of non-aspirin-related peptic ulcer disease or a history of aspirin-related gastrointestinal complications (dyspepsia or peptic ulcer) were recruited. The occurrence of ulcer complications (bleeding/perforation/obstruction) was the primary end-point.
  
  
  RESULTS
  After a median follow-up of 1 year, nine patients (12%) developed gastrointestinal bleeding and one had a perforated peptic ulcer. Clopidogrel-associated gastrointestinal bleeding was significantly more common in patients with a history of gastrointestinal bleeding than in those without (22% vs. 0%; P = 0.007; odds ratio, 1.3; 95% confidence interval, 1.1-1.5).
  
  
  CONCLUSIONS
  Clopidogrel is associated with a high incidence of upper gastrointestinal bleeding in high-risk patients. A previous history of gastrointestinal bleeding appears to be a predictor of adverse gastrointestinal events.
authors.affiliation: Department of Medicine, Ruttonjee Hospital, Hong Kong.
authors.forename: F H
authors.initials: FH
authors.lastname: Ng
authors.forename: S Y
authors.initials: SY
authors.lastname: Wong
authors.forename: C M
authors.initials: CM
authors.lastname: Chang
authors.forename: W H
authors.initials: WH
authors.lastname: Chen
authors.forename: C
authors.initials: C
authors.lastname: Kng
authors.forename: A I
authors.initials: AI
authors.lastname: Lanas
authors.forename: B C Y
authors.initials: BC
authors.lastname: Wong
mesh_terms: D000368:Aged; D001241:Aspirin / Q000009:adverse effects; D000077144:Clopidogrel; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006471:Gastrointestinal Hemorrhage / Q000139:chemically induced*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D010437:Peptic Ulcer / Q000150:complications* / Q000188:drug therapy; D010975:Platelet Aggregation Inhibitors / Q000009:adverse effects*; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors; D013988:Ticlopidine / Q000009:adverse effects* / Q000031:analogs & derivatives
chemical_list: D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; D013988:Ticlopidine; D001241:Aspirin