title: Inverse association between nonsteroidal anti-inflammatory drugs and prostate cancer.
abstract: BACKGROUND
  Prostate cancer is considered a major health problem in western countries. Promising results from observational studies on cancer at other sites fuelled the publication of several studies assessing the association between nonsteroidal anti-inflammatory drug (NSAID) use and prostate cancer. However, these studies show conflicting results.
  
  
  METHODS
  We conducted a cohort study with a nested case-control analysis to further study the association between NSAIDs and prostate cancer. We used data from the General Practice Research Database in United Kingdom.
  
  
  RESULTS
  Aspirin use was associated with a reduced risk of prostate cancer [odds ratio (OR) = 0.70, 95% confidence interval (95% CI) = 0.61-0.79]. We also found that paracetamol use with a treatment duration longer than 1 year was associated with a decreased risk (OR = 0.65, 95% CI = 0.54-0.78). Non-aspirin-NSAID (NA-NSAID) and paracetamol short-term use was associated with a small increased risk whereas long-term users of NA-NSAIDs presented an OR of 0.89 (95% CI = 0.73-1.08).
  
  
  CONCLUSIONS
  Our findings support a protective effect of aspirin and paracetamol against prostate cancer. The transient elevated risk observed among newly started users of NA-NSAIDs and paracetamol is most likely explained by prothopathic bias. We found some suggestion of a reduced risk with long-term use of NA-NSAID.
authors.affiliation: Centro Español de Investigación Farmacoepidemiológica (CEIFE), Almirante 28-2, 28004 Madrid, Spain.
authors.forename: Luis A
authors.initials: LA
authors.lastname: García Rodríguez
authors.forename: Antonio
authors.initials: A
authors.lastname: González-Pérez
mesh_terms: D000082:Acetaminophen / Q000008:administration & dosage*; D000368:Aged; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage*; D001241:Aspirin / Q000008:administration & dosage; D016022:Case-Control Studies; D015331:Cohort Studies; D016208:Databases, Factual; D006801:Humans; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000097:blood / Q000453:epidemiology* / Q000209:etiology / Q000517:prevention & control*; D012307:Risk Factors; D006113:United Kingdom / Q000453:epidemiology
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D000082:Acetaminophen; D001241:Aspirin