Risk factors of poor bowel preparation before colonoscopy: a retrospective cohort study

Abstract

Abstract Background: Colonoscopy is the standard and most effective screening tool for colonic diseases and the accuracy of colonoscopy depends on the quality of bowel preparation. The aim of this study was to analyze the risk factors for poor bowel preparation before colonoscopy.Methods: In this retrospective study, patients who underwent colonoscopy from January 2018 to December 2018 were included. Polyethylene Glycol Electrolytes Powder (Ⅳ) + simethicone was used for bowel preparation. Patient- and procedure-related parameters were recorded. The primary outcome was the quality of bowel preparation. Risk factors for poor bowel preparation were identified using multivariate logistic regression analysis. Results: A total of 6720 patients were included in the present study. The mean age of these patients was 49.69±12.96 years old. There were 3467 (51.59%) males. Inadequate bowel preparation was found in 233 (12.37%), 139 (6.42%), 131 (6.96%), 68 (8.6%) patients in spring, summer, autumn and winter respectively. On the multivariate analysis, age, sex, inpatient status and the season when colonoscopy was performed were the independent risk factors for poor bowel preparation. Using winter as a reference, patients in spring had a worse bowel preparation, while patients in summer were more easily to have adequate colon preparation. There is no statistically significant difference between bowel preparation in autumn.Conclusions: Male, inpatient status and spring season were the independent risk factors for poor bowel preparation. Compared with autumn and summer, patients in spring may need intensive bowel preparation. Male patients and inpatients should receive more enhanced instructions for bowel preparation.