Patient factors predictive of inadequate bowel preparation using polyethylene glycol: a prospective study in Korea.

Inadequate bowel preparation is important because it can result in missed lesions, cancelled procedures, increased procedural time, and a potential increase in complication rates. This prospective study was designed to look at the quality of colon preparation using polyethylene glycol solution and evaluate potential associations between specific patient characteristics and inadequate bowel preparation. A total of 362 patients who were compliant with preparation instructions were enrolled. All colonoscopic examinations were performed by an experienced endoscopist and the quality of the preparation was graded by the endoscopist (excellent to poor). Patient demographic and medical history information was gathered before the procedure. Possible predictors of inadequate colonic preparation were analyzed using univariate statistics and multivariate logistic regression models. An inadequate bowel preparation was reported in 28.2% of observed colonoscopies. In multivariate regression analysis, age greater than 60 years [odds ratio (OR) 2.8, 95% confidence interval (CI) 1.04-7.4], a history of diabetes (OR 8.6, 95% CI 6.3-19.4), a history of appendectomy (OR 4.6, 95% CI 2.0-10.5), a history of colorectal resection (OR 7.5, 95% CI 3.4-17.6), and a history of hysterectomy (OR 3.4, 95% CI 1.1-10.4) were independent predictors of an inadequate colon preparation. This prospective study identified several factors that may predict inadequate polyethylene glycol preparation independent of compliance with preparation instructions and procedure starting time. This result may help to identify patients at an increased risk for inadequate bowel preparation for whom alternative preparation protocols would be beneficial.