title: Cardioprotective aspirin users and their excess risk of upper gastrointestinal complications.
abstract: BACKGROUND
  To balance the cardiovascular benefits from low-dose aspirin against the gastrointestinal harm caused, studies have considered the coronary heart disease risk for each individual but not their gastrointestinal risk profile. We characterized the gastrointestinal risk profile of low-dose aspirin users in real clinical practice, and estimated the excess risk of upper gastrointestinal complications attributable to aspirin among patients with different gastrointestinal risk profiles.
  
  
  METHODS
  To characterize aspirin users in terms of major gastrointestinal risk factors (i.e., advanced age, male sex, prior ulcer history and use of non-steroidal anti-inflammatory drugs), we used The General Practice Research Database in the United Kingdom and the Base de Datos para la Investigación Farmacoepidemiológica en Atención Primaria in Spain. To estimate the baseline risk of upper gastrointestinal complications according to major gastrointestinal risk factors and the excess risk attributable to aspirin within levels of these factors, we used previously published meta-analyses on both absolute and relative risks of upper gastrointestinal complications.
  
  
  RESULTS
  Over 60% of aspirin users are above 60 years of age, 4 to 6% have a recent history of peptic ulcers and over 13% use other non-steroidal anti-inflammatory drugs. The estimated average excess risk of upper gastrointestinal complications attributable to aspirin is around 5 extra cases per 1,000 aspirin users per year. However, the excess risk varies in parallel to the underlying gastrointestinal risk and might be above 10 extra cases per 1,000 person-years in over 10% of aspirin users.
  
  
  CONCLUSIONS
  In addition to the cardiovascular risk, the underlying gastrointestinal risk factors have to be considered when balancing harms and benefits of aspirin use for an individual patient. The gastrointestinal harms may offset the cardiovascular benefits in certain groups of patients where the gastrointestinal risk is high and the cardiovascular risk is low.
authors.affiliation: Department of Epidemiology, Harvard School of Public Health, Boston, MA, USA. shernan@hsph.harvard.edu
authors.forename: Sonia
authors.initials: S
authors.lastname: Hernández-Díaz
authors.forename: Luis A
authors.initials: LA
authors.lastname: García Rodríguez
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000009:adverse effects / Q000627:therapeutic use; D001241:Aspirin / Q000009:adverse effects*; D002316:Cardiotonic Agents / Q000009:adverse effects*; D015331:Cohort Studies; D016208:Databases, Factual; D005767:Gastrointestinal Diseases / Q000139:chemically induced* / Q000453:epidemiology*; D006801:Humans; D008875:Middle Aged; D010437:Peptic Ulcer / Q000139:chemically induced / Q000453:epidemiology; D012306:Risk; D018570:Risk Assessment
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D002316:Cardiotonic Agents; D001241:Aspirin