[Factors related to a suboptimal bowel preparation for colonoscopy]

Colonoscopy is the standard method for the evaluation of the colon. A suitable intestinal cleaning is critical for the effectiveness and security of the procedure, but unfortunately there is a high proportion of suboptimal bowel preparation.

To identify factors related to suboptimal bowel preparation.

We performed an analytic, observational, cross-sectional and prospective study. We included all outpatients scheduled for colonoscopy in the Peruvian-Japanese Health Center between January and July 2012. We excluded patients with a complete or partial colonic resection. In patients with two or more colonoscopies during the study interval, only the first procedure was considered. Aronchick scale was used in assessment of bowel cleaning. The variables studied with relationship to bowel preparation were: age, sex, grade ofeducation, body mass index, time of examination, history (diabetes mellitus, stroke, cirrhosis, use of antidepressants/anxiolytics, number of bowel movements per week, abdominal surgery, personal history of previous colonoscopy, polyps and colon cancer, family history of colon cancer), received purgative, additional laxative, indication for colonoscopy and adverse effects of the preparation. Statistical analysis was made with SPSS v.160. For the categorical variables we used chi square test or Fisher exact test, whereas for continuous variables the Mann Whitney test was used. The variables significantly associated with suboptimal preparation in the univariated analysis were included in a multivariate analysis using logistic regression.

We included 841 patients. The bowel preparation was suboptimal in 438 patients (52.1%). The univariate analysis showed that the factors related to suboptimal preparation were age (P = 0.023) and body mass index ≥ 30 kg/m2 (P = 0.021). The multivariate analysis confirmed that age ≥ 70 years old (P = 0.001) and body mass index ≥ 30 kg/m2 (P = 0.010) were the variables related to suboptimal bowel preparation.

Age greater than 70 years old and obesity are factors related to suboptimal bowel preparation.