Risk of breast cancer among users of aspirin and other anti-inflammatory drugs

Br J Cancer. 2004 Aug 2;91(3):525-9. doi: 10.1038/sj.bjc.6602003.


We conducted a cohort study with a nested case-control analysis to evaluate the effect of anti-inflammatory drugs in breast cancer incidence using the General Practice Research Database. Women taking aspirin and paracetamol for 1 year or longer had an odds ratio (OR) of 0.77 (95 percent confidence interval (95% CI): 0.62,0.95) and 0.76 (95% CI: 0.65,0.88), respectively, compared to nonusers. Daily doses of aspirin (75 mg) and paracetamol (up to 2000 mg) showed the greatest reduced risk. Use of non-aspirin nonsteroidal anti-inflammatory drugs for more than 1 year was not associated with a reduced risk of breast cancer (OR=1.00 (95% CI: 0.84, 1.17), and the corresponding estimate among users with at least 2 years duration was similar. Our findings suggest that aspirin at cardioprophylactic doses as well as paracetamol at analgesic doses is associated with a reduced risk of breast cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Anti-Inflammatory Agents, Non-Steroidal / adverse effects*
  • Aspirin / adverse effects*
  • Breast Neoplasms / epidemiology*
  • Breast Neoplasms / etiology*
  • Breast Neoplasms / prevention & control
  • Case-Control Studies
  • Cohort Studies
  • Databases, Factual
  • Female
  • Humans
  • Middle Aged
  • Odds Ratio
  • Risk Assessment


  • Anti-Inflammatory Agents, Non-Steroidal
  • Aspirin