Effects of Colorectal Cancer Risk Factors on the Association Between Aspirin and Colorectal Cancer

Background/Aim: We investigated the effect of aspirin on colorectal cancer (CRC) risk among subgroups of women with and without risk factors for CRC. Patients and Methods: Using data from the Women's Health Initiative, we estimated hazard ratios for CRC in association with aspirin use, with stratifications by cardiovascular disease (CVD) risk status, family history of CRC, and history of colorectal polypectomy. Results: Aspirin was associated with a lower risk of CRC among women with low/normal or high CVD-risk status; no family history of CRC; or a history of colonoscopy with polypectomy. Aspirin was not associated with CRC among women with a family history of CRC or a history of colonoscopy without polypectomy. Conclusion: Aspirin was associated with a lower risk of CRC in women at all levels of CVD-risk, in those with a history of colonoscopy with polypectomy, and in those without a family history of CRC.