Better Segmental Bowel Preparation Scores Correlate with Higher Advanced Adenoma Detection Rates During Screening Colonoscopy

Abstract

Purpose: A primary goal for screening colonoscopy is advanced adenoma detection rate (ADR). The Boston Bowel Preparation Score (BBPS) has been standardized to improve reporting of bowel prep using segmental scores. Right sided colonic polyps are more likely to be adenomatous/pre-cancerous. Split dose bowel preparation has been devised to improve right colon preparation. This study aims to determine the correlation of the right sided segmental BBPS with ADR. Methods: This prospective study enrolled 265 consecutive patients reporting for screening colonoscopy. After colonoscopy, the endoscopist was asked to grade quality of bowel preparation using the BBPS. ADR on the right side of the colon was determined by reviewing the histopathology of excised polyps. Results: In the 265 study subjects enrolled, BBPS in the right colon (BBPS-R) was 3 in 127/265 (47.9%) (R-3, good), 2 in 111/265 (41.9%) (R-2, suboptimal) and 1 in 27/265 (10.2%) (R-1, poor). Right sided ADR was 7.1% in R-3 group, 2.7% in R-2 group and no advanced adenomas were seen in R-1 group. There was a significant linear correlation with the BBPS-R and right colonic ADR (p=0.05). A similar trend was also seen with other polyps (tubular adenomas and hyperplastic polyps). 14.9% in R-3 group, 14.4% in R-2 group and 3.7% in R-1 group. Conclusion: This study suggests that colonoscopy reports should detail quality of bowel preparation by segments. Attention to improving quality of preparation in the right colon appears to improve detection of advanced adenomas, an important outcome measure for screening colonoscopy.