Association between bowel habits and quality of bowel preparation for colonoscopy

The effectiveness of colonoscopy is highly dependent on the quality of bowel preparation. Although many studies have previously evaluated the role of cleansing methods and dosing regimens, few have examined the association between bowel habits and subsequent bowel preparation. Here, we aimed to evaluate the impact of bowel habits on the quality of bowel preparation. A total of 404 patients who underwent a total colonoscopy and completed a personal bowel habit questionnaire at Korea University Hospital between December 2012 and December 2013 were enrolled. The usual stool form of patients was classified into 7 categories according to the Bristol Stool Scale (BSS). The quality of bowel preparation was determined during colonoscopy according to the Ottawa Bowel Preparation Scale (OBPS). Segment scores of ≥3 or total OBPS scores of >7 were defined as poor bowel preparation. Poor bowel preparation was reported in 9.4% of observed colonoscopies. The odds ratio (OR) of poor bowel preparation being associated with infrequent bowel movements (<3/week) was 5.00 (95% confidence interval [CI], 1.91–13.1, P = .001). BSS types 1 and 2 tended to have an association with poor bowel preparation, but the association was statistically insignificant (OR: 2.38; 95% CI, 0.90–6.33, P = .082). After adjusting for age, sex, drinking, presence of diabetes mellitus, and bowel preparation regimen, infrequent bowel movement (<3/week) was still significantly associated with poor bowel preparation. When subdividing by colonic segment, it was significantly associated with poor bowel preparation in all segments. Infrequent bowel movement (<3/week) was significantly associated with poor bowel preparation.