The impact of colonoscopy indication on polyp detection rate

Adenoma/polyp detection rates are considered to be among the most important quality indicators of colonoscopy and are key measures of a quality procedure. However, they are designed for use in the screening setting and are not amenable to other colonoscopy indications. Little is known about their significance in other colonoscopy indications. We aimed to evaluate the impact of the various indications on polyp detection rate (PDR).

This was a retrospective, single-center study. Electronic reports of index colonoscopy procedures with adequate bowel preparation over a 10-year period were reviewed. Patients were divided into 7 groups based on the study indication. PDR was determined for each group and was compared to that of a control group, the screening indication group. Adjustment was made for potential confounders such as age, sex, and procedural setting.

A total of 13,054 patients were considered suitable for the study. PDR was greatest in the positive fecal occult blood test group, with a value of 33.1% (P<0.01). Overall, the remaining groups showed similar PDRs compared with screening (22.1% vs. 20.4%; P=0.15). This trend persisted in a multivariate analysis, which showed the odds ratio in the positive fecal occult blood test group to be significantly higher, with a value of 1.955 (1.759-2.172, P<0.001) compared with the screening group.

PDR was highest for the positive fecal occult blood test indication, but was not affected significantly by most indications. Further randomized studies are warranted to confirm these findings and help calculate recommended thresholds for "overall" PDR.