Background: There is increasing evidence that aspirin, statins and ACE-inhibitors can reduce the incidence of colorectal cancer. The aim of the present study was to assess the impact of these medications on an individual's risk of advanced neoplasia in a colorectal cancer screening programme.
Methods: A prospectively maintained database of the first round of screening in our geographical area was analysed. The outcome measure was advanced neoplasia (cancer or intermediate or high risk adenomata).
Results: Of the 4188 individuals who underwent colonoscopy following a positive occult blood stool test, colorectal pathology was present in 3043(73%). Of the 3043 patients with colorectal pathology, 1704(56%) had advanced neoplasia. Patients with advanced neoplasia were more likely to be older (OR 1.38; 95% CI 1.19-1.59) and male (OR 1.66; 95% CI 1.43-1.94) (both P<0.001). In contrast, those on aspirin (OR 0.68; 95% CI 0.56-0.83), statins (OR 0.65; 95% CI 0.55-0.78) or ACE inhibitors (OR 0.71; 95% CI 0.57-0.89) were less likely to have advanced neoplasia at colonoscopy (all P<0.05).
Conclusion: In patients undergoing colonoscopy following a positive occult blood stool test with documented evidence of aspirin, statin or ACE-inhibitor usage, advanced neoplasia is less likely, suggesting that the usage of these medications may have a chemopreventative effect.