Colonoscopy Indication and Gender May Predict Colonic Prep Quality

Background: Inadequate bowel preparation for colonoscopies is a frequent reason cited to repeat and / or abort procedures. Unfortunately, inadequate bowel prep is only discovered during the actual colonoscopy. Patients are then required to undergo the discomfort and inconvenience of repeating the prep process. The purpose of this study is to report our center experience with inadequate bowel prep and determine predictors of both inadequate prep and the need for repeat colonoscopy. Methods: Using our computerized endoscopy reporting system, we selected a random sample of 500 consecutive patients who underwent colonoscopy between 10/07 and 12/07. Data retrieved included demographics, procedure related variables, reported prep quality, indications and findings. Non -parametric tests and logistic regression models were used to assess the associations and estimate the odd ratio (OR) and 95% confidence intervals (CI) of these associations. Results: 500 subjects (225 males (45%) and 275 females (55%) with a mean age 49 yrs (18-82), Indications were: screening 230 (46%) [125 (25%) average risk and 105 (21%) high risk], surveillance 56 (11.2%), blood in stool 86 (17.2%), and miscellaneous indications 128 (25.6%). Prep quality was reported as: excellent 11.8%, good 41%, fair 34.2%, poor 13%. Procedure was discontinued in 7.4% of subjects secondary to poor prep. There was a statistically significant correlation between age and pathologic finding (OR 3.1, 95% CI: 1.7-8.6). In the multivariate analysis there was a significant correlation between prep quality and gender after controlling for age and procedure indication. Women were less likely to have poor quality (OR 0.76, 95%CI 0.39-0.95). In addition, screening in average risk subjects was associated with higher frequency of suboptimal prep compared to screening in high risk and surveillance (74/125 (59%) vs 64/161 (40%) in high risk/surveillance indication (p =0.001; OR: 3.2; 95% CI: 1.7-8.3). Conclusions: This investigation of prep quality predictors and consequences shows that 47.2% of subjects who undergo colonoscopies are reported to have suboptimal prep quality. Furthermore, women are noted to have superior prep quality than men. Subjects who underwent colonoscopy for surveillance or high risk CRC indications had superior prep quality when compared to subjects with screening for average risk or other indications. Further larger studies are needed to ascertain findings and provide potential explanation.