title: Risk of upper gastrointestinal bleeding associated with use of low-dose aspirin.
abstract: OBJECTIVE
  Aspirin products are known to cause irritation and injury to the gastric mucosa. We examined the risk of hospitalization for upper gastrointestinal bleeding with use of low-dose aspirin.
  
  
  METHODS
  This was a cohort study based on record linkage between a population-based prescription database and a hospital discharge registry in North Jutland County, Denmark, from January 1, 1991, to December 31, 1995. Incidence rates of upper gastrointestinal bleeding in 27,694 users of low-dose aspirin were compared with the incidence rates in the general population in the county.
  
  
  RESULTS
  A total of 207 exclusive users of low-dose aspirin experienced a first episode of upper gastrointestinal bleeding with admission to the hospital during the study period. The standardized incidence rate ratio was 2.6 (95% confidence interval, 2.2-2.9), 2.3 in women and 2.8 in men. The standardized incidence rate ratio for combined use of low-dose aspirin and other nonsteroidal anti-inflammatory drugs was 5.6 (95% confidence interval, 4.4-7.0). The risk was similar among users of noncoated low-dose aspirin (standardized incidence rate ratio, 2.6; 95% confidence interval, 1.8-3.5) and coated low-dose aspirin (standardized incidence rate ratio, 2.6; 95% confidence interval, 2.2-3.0).
  
  
  CONCLUSIONS
  Use of low-dose aspirin was associated with an increased risk of upper gastrointestinal bleeding, with still higher risks when combined with other nonsteroidal anti-inflammatory drugs. Enteric coating did not seem to reduce the risk. The findings from this observational study raise the possibility that prophylactic use of low-dose aspirin may convey an increased risk of gastrointestinal bleeding, which may offset some of its benefits.
authors.affiliation: Department of Clinical Epidemiology, Aarhus University and Aalborg Hospitals, Denmark.
authors.forename: H T
authors.initials: HT
authors.lastname: Sørensen
authors.forename: L
authors.initials: L
authors.lastname: Mellemkjaer
authors.forename: W J
authors.initials: WJ
authors.lastname: Blot
authors.forename: G L
authors.initials: GL
authors.lastname: Nielsen
authors.forename: F H
authors.initials: FH
authors.lastname: Steffensen
authors.forename: J K
authors.initials: JK
authors.lastname: McLaughlin
authors.forename: J H
authors.initials: JH
authors.lastname: Olsen
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000009:adverse effects*; D001241:Aspirin / Q000008:administration & dosage / Q000009:adverse effects*; D015331:Cohort Studies; D016001:Confidence Intervals; D003718:Denmark / Q000453:epidemiology; D003937:Diagnosis, Differential; D005260:Female; D006471:Gastrointestinal Hemorrhage / Q000139:chemically induced* / Q000175:diagnosis / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D004366:Nonprescription Drugs; D012189:Retrospective Studies; D017678:Sex Distribution; D011795:Surveys and Questionnaires
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D004366:Nonprescription Drugs; D001241:Aspirin