Factors That Affect Adequacy of Colon Cleansing for Colonoscopy in Hospitalized Patients

Hospitalization is associated with inadequate colon cleansing before colonoscopy. We aimed to identify factors associated to inadequate colon cleansing among inpatients, and to derive and validate a model to identify inpatients with inadequate cleansing.

We performed a prospective observational study at 12 hospitals in Italy. Consecutive adult inpatients scheduled for colonoscopy for any indication were enrolled from February through May 2019 (derivation cohort, n = 1016) and from June through August 2019 (validation cohort, n = 508). Inadequate cleansing was defined as Boston bowel preparation scale scores below 2 in any colon segment. We performed multivariate logistic regression to identify factors associated with inadequate cleansing.

In the combined cohorts, 1032 patients (68%) had adequate colon cleansing. Physicians' meetings to optimize bowel preparation (odds ratio [OR], 0.42; 95% CI, 0.27-0.65), written and oral instructions to patients (OR, 0.48; 95% CI, 0.36-0.65), admission to gastroenterology unit (OR, 0.71; 95% CI, 0.51-0.98), split-dose regimens (OR, 0.27; 95% CI, 0.20-0.35), a 1-liter polyethylene glycol-based bowel purge (OR, 0.39; 95% CI, 0.23-0.65), and 75% or more intake of bowel preparation (OR, 0.09; 95% CI, 0.05-0.15) significantly reduced odds of inadequate colon cleansing. Alternatively, bedridden status (OR, 2.14; 95% CI, 1.55-2.98), constipation (OR, 2.16; 95% CI, 1.55-3.0), diabetes mellitus (OR, 1.61; 95% CI, 1.18-2.20), use of anti-psychotic drugs (OR, 3.26; 95% CI, 1.62-6.56), and 7 or more days of hospitalization (OR, 1.02; 95% CI, 1.00-1.04) increased risk of inadequate colon cleansing. We developed a model to identify patients with inadequate cleaning using data from patients in the derivation cohort and tested it in the validation cohort. Calibration values were P = .218 for the discrimination cohort and P = .232 for the validation cohort. Discrimination values were c-statistic, 0.78 (95% CI, 0.74-0.81) for the discrimination cohort and c-statistic, 0.73 (95% CI, 0.69-0.78) for the validation cohort. We developed app for use by clinicians.

In a prospective observational study, we identified setting-, patient- and preparation-related factors that affect colon cleansing among inpatients. We derived and validated a model to identify patients with inadequate preparation and developed an app for clinicians. ClinicalTrials.gov no: NCT03925506.