['Studies have suggested that statins may protect against colorectal cancer (CRC), but it is not clear whether that protection results from effects on established adenomatous polyps (APs) or from preventing the development of new APs. We have conducted a retrospective, cohort study to explore how the long-term use of statins influences the development of new APs.', 'We reviewed endoscopy and pathology databases to identify patients with histologically verified APs, all of which were removed during an index colonoscopy, and who had a follow-up colonoscopy 3-5 years later. Patients were categorized as users or nonusers of statins by review of their medical and pharmacy records, and the characteristics of APs found on follow-up colonoscopy in the 2 groups was compared.', 'We identified 2,626 patients (84% men, mean age 62.2 years) with APs removed during an index colonoscopy. Of 1,688 patients (35%) who used statins continuously, 583 had an AP found on follow-up colonoscopy, compared to 477 of 938 patients (51%) who did not use statins continuously [odds ratio (OR) 0.51, 95% confidence interval (CI) 0.43-0.60; p < 0.01]. Statin use was associated with a smaller mean number of polyps (2.6 vs. 3.1; p = 0.002), a smaller mean polyp size (7.1 vs. 7.9 mm; p = 0.03) and a significant reduction in the incidence of advanced APs (OR 0.74, 95% CI 0.52-0.96; p = 0.03).'] Is the long-term use of statins associated with a decreased incidence of adenomatous colon polyps?