Distal hyperplastic polyps do not predict proximal adenomas: results from a multicentric study of colorectal adenomas

Background: The association between distal hyperplastic polyps and proximal adenomas is still a matter of debate. We investigated this association while taking into account patient characteristics. Methods: After exclusion of patients with inflammatory bowel diseases, familial adenomatous polyposis, or any cancer, 3088 eligible consecutive subjects aged 18 to 69 years underwent total colonoscopy in four gastroenterology units. The odds ratios (OR) of having proximal adenomas according to patient characteristics (age, sex, medical center, year of endoscopy, reasons for referral, and distal findings) were estimated in univariate and multivariate analyses. Results: Patients with distal polyps of any type showed an adjusted OR of 2.5 (95% Cl [1.9, 3.1] p < .001) of having proximal adenomas as compared with those without distal polyps. When distal adenomas and distal hyperplastic polyps were included in the multivariate model as independent factors, the presence of adenomas significantly increased the risk of proximal adenomas (OR = 2.8: 95% Cl [2.2, 3.6] p < .001), whereas the presence of hyperplastic polyps did not (OR = 1.1: 95% Cl [0.8, 1.5] p = .64). No association with number, size, or location of distal hyperplastic polyps was seen. Conclusions: Our data show that the presence of hyperplastic polyps should not be the sole indication for total colonoscopy because they are not associated with proximal adenomas when adjusting for patient characteristics and presence of distal adenomas.