No higher risk for colorectal adenomas with colonic diverticula

Last Updated: 2015-11-17

By Laura Newman

NEW YORK (Reuters Health) - Patients with colonic diverticula have no greater risk for colorectal adenomas, according to a new prospective study.

"This finding should be reassuring for patients with diverticula," said Dr. Anne F. Peery of the University of North Carolina School of Medicine in Chapel Hill, in an interview with Reuters Health. "Most of the literature until now has not been done prospectively. Here, we did a very simple study, looking at first-time colonoscopy, looking meticulously for deep, large, inflamed pockets, and muscle hypertrophy."

Dr. Peery's team enrolled 624 patients undergoing first-time screening colonoscopy at the University of North Carolina Hospitals in Chapel Hill, between 2013 and 2015. Participants were age 30 and older, with an adequate preparation for colonoscopy and a complete examination to the cecum.

As reported online November 3 in the American Journal of Gastroenterology, 216 patients (35%) had one or more colorectal adenomas. There was no tie between diverticula identified on colonoscopy and an increased risk of adenoma (odds ratio, 1.0; 95% CI 0.7-1.4) or advanced adenoma (OR 0.8; 95% CI 0.4-1.5). Even patients with 10 or more diverticula did not have an elevated risk for adenoma (OR 1.1; 95% CI 0.7-1.8) compared to patients with no diverticula.

In terms of location, colonic diverticula were not linked to an increased risk of proximal (OR 1.0; 95% CI 0.6-1.6) or distal adenoma (OR 1.0; 95% CI 0.6-1.7).

Dr. Peery explained, "Diverticula can distort the architecture of the colon and they are very common. Whether diverticula are linked to adenomas has been a question until now."

Dr. Thomas Imperiale of Indiana University and the Regenstrief Health Center in Indianapolis, who has studied screening for colorectal cancer, praised the research in a telephone interview with Reuters Health.

"This is a very well done study by a very careful group of investigators finding no association between diverticulosis and adenomas," he said. "What's different about this study is that it was done prospectively and very carefully. The investigators counted adenomas meticulously and adjusted thoroughly for confounders."

He added: "The only drawback is that the sample sizes were small and some of the confidence intervals were rather broad."

Dr. Imperiale cautioned that the study is also limited to first-time screening. Therefore, "you can't really say anything definitive about the relationship between diverticulosis and adenoma risk beyond the fist-time screening subgroup," he said.

SOURCE: http://bit.ly/1MkUeRr

Am J Gastroenterol 2015.