Modifiable Factors Associated with Quality of Bowel Preparation Among Hospitalized Patients Undergoing Colonoscopy
INTRODUCTION: Inadequate bowel preparation (IBP) is a common problem in hospitalized patients; however, little is known about how to prevent IBP. In a large, multihospital system, we evaluated the association between modifiable factors and IBP rate.
METHODS: We reviewed data from adult (≥18 years) inpatients undergoing colonoscopy between January 2011 and June 2017. Colonoscopies performed in the intensive care unit or lacking descriptions of bowel preparation quality were excluded. Multivariate logistic regression analysis was performed to identify factors associated with IBP. A counterfactual analysis was performed to assess the potential contribution of modifiable factors to IBP.
RESULTS: Of 8,819 patients that were included (median age of 64 years; 50.5% female), 51% had IBP. Patients with IBP stayed in the hospital one day longer than those with adequate bowel preparation (P < .001). Modifiable factors associated with IBP include opiate use within three days of colonoscopy (OR, 1.31; 95% CI, 1.18, 1.45), colonoscopy performed after 12:00 pm (OR, 1.25; 95% CI, 1.1, 1.41), and solid diet the day before colonoscopy (OR, 1.37; 95% CI, 1.18, 1.59). In the counterfactual analysis, if all patients avoided these three conditions, adjusted IBP rates were reduced by 5.6%.
CONCLUSIONS: Among hospitalized patients undergoing colonoscopy, IBP rates are high and associated with an increased length of stay. Avoiding opiates before colonoscopy, performing colonoscopy before noon, and maintaining patients on a liquid diet or nil per os might significantly reduce IBP rates.
© 2019 Society of Hospital Medicine
Inadequate bowel preparation (IBP) at the time of inpatient colonoscopy is common and associated with increased length of stay and cost of care.1 The factors that contribute to IBP can be categorized into those that are modifiable and those that are nonmodifiable. While many factors have been associated with IBP, studies have been limited by small sample size or have combined inpatient/outpatient populations, thus limiting generalizability.1-5 Moreover, most factors associated with IBP, such as socioeconomic status, male gender, increased age, and comorbidities, are nonmodifiable. No studies have explicitly focused on modifiable risk factors, such as medication use, colonoscopy timing, or assessed the potential impact of modifying these factors.
In a large, multihospital system, we examine the frequency of IBP among inpatients undergoing colonoscopy along with factors associated with IBP. We attempted to identify
METHODS
Potential Predictors of IBP
Demographic data such as patient age, gender, ethnicity, body mass index (BMI), and insurance/payor status were obtained from the electronic health record (EHR). International Classification of Disease 9th and 10th revision, Clinical Modifications (ICD-9/10-CM) codes were used to obtain patient comorbidities including diabetes, coronary artery disease, heart failure, cirrhosis, gastroparesis, hypothyroidism, inflammatory bowel disease, constipation, stroke, dementia, dysphagia, and nausea/vomiting. Use of opioid medications within three days before colonoscopy was extracted from the medication administration record. These variables were chosen as biologically plausible modifiers of bowel preparation or had previously been assessed in the literature.1-6 The name and volume, classified as 4 L (GoLytely®) and < 4 liters (MoviPrep®) of bowel preparation, time of day when colonoscopy was performed, solid diet the day prior to colonoscopy, type of sedation used (conscious sedation or general anesthesia), and total colonoscopy time (defined as the time from scope insertion to removal) was recorded. Hospitalization-related variables, including the number of hospitalizations in the year before the current hospitalization, the year in which the colonoscopy was performed, and the number of days from admission to colonoscopy, were also obtained from the EHR.
