Optimizing bowel preparation for colonoscopy: what are the predictors of an inadequate preparation?

Bowel preparation with linaclotide and 1 L polyethylene glycol plus ascorbic acid prior to colonoscopy in chronic constipated patients

BACKGROUND AND AIMS

Information on effective bowel preparation (BP) methods for patients with constipation is limited. We recently reported the efficacy of 1 L polyethylene glycol plus ascorbic acid (PEG-Asc) combined with senna for BP; however, this regimen was insufficient in patients with constipation. We hypothesized that the addition of linaclotide, which is approved for the treatment of chronic constipation, to 1 L PEG-Asc would yield results superior to those of senna in patients with constipation.

METHODS

This was a retrospective, single-center study that included outpatients with constipation who underwent BP prior to colonoscopy between March and December 2019 (receiving 1 L PEG-Asc with 24 mg senna) and between January and October 2020 (receiving 1 L PEG-Asc with 500 mg linaclotide).

RESULTS

A total of 543 patients with constipation were included, of whom 269 received linaclotide and 274 received senna. The rate of inadequate BP was significantly lower (11% vs 20%, p < 0.01) and the adenoma detection rate was significantly higher (54% vs 45%, p = 0.04) in the linaclotide group than in the senna group. Multivariate analysis revealed that the linaclotide regimen significantly reduced the risk of inadequate BP (odds ratio = 0.36, 95% confidence interval = 0.21-0.60, p < 0.01).

CONCLUSIONS

The linaclotide regimen significantly increased BP efficacy and the adenoma detection rate compared with the senna regimen without reducing tolerability and is therefore a promising new option for BP in patients with constipation.

Incidence and predicting factors of inadequate bowel preparation for colonoscopy: A cross-sectional study

Background and Aim

Adequate bowel preparation is necessary for optimal colonoscopy. Inadequate bowel preparation results in increased costs and imprecise colonoscopy results. This study aims to determine the incidence and risk factors of inadequate bowel preparation.

Methods

In this study, 604 consecutive patients were observed prospectively who underwent colonoscopy examination. The patient's clinical and demographic data were obtained on the day of the procedure. Bowel preparation was evaluated by Boston Bowel Preparation Scale (BBPS) and was divided into two groups; adequate and inadequate. Univariate and multivariate analyses were performed.

Results

Inadequate bowel preparation incidence was 17.9%. In the univariate analysis, education level (P value = 0.009), body mass index (P value = 0.03), admission type (P value = 0.038), previous history of colonoscopy (P value = 0.03), color and consistency of the last feces (P value = 0.03), diabetes (P value = 0.004), and smoking (P value = 0.03) were significantly related with the incidence of inadequate bowel preparation. While ischemic heart disease (IHD) decreased the level of inadequate bowel preparation (P value = 0.047). Multivariate analysis showed that diabetes mellitus (odds ratio [OR] = 2.18), smoking (OR = 2.10), inpatient status of admission type (OR = 3.32), last stool that was non-watery (OR = 1.60), and ischemic heart disease (OR = 0.032) were independent factors associated with inadequate bowel preparation.

Conclusion

Diabetic patients, smokers, inpatients and who defecated a non-watery and colory stool as the last defecation are at risk of inadequate bowel preparation and need more potent regimens. It is important to inform patients about preventable factors that affect bowel preparation to improve their preparation outcomes.

Single-center experience with intraprocedural cleansing system to improve inadequate bowel preparation during colonoscopy

Inadequate bowel preparation is common despite various preprocedure interventions. There is a need for an intervention at the time of colonoscopy to combat poor preparation. In this retrospective, observational study of 46 patients, we evaluated the clinical efficacy and feasibility of implementing the third generation of the Pure-Vu EVS System, a US Food and Drug Administration-cleared over-the-scope-based intraprocedural cleansing device, into our practice at the Minneapolis VA Medical Center (Minneapolis, Minnesota, United States). To study clinical efficacy, we measured bowel preparation adequacy before and after using the device, as measured by the Boston Bowel Preparation Score, and reviewed colonoscopy surveillance interval recommendations. Technical success and feasibility of using the device were measured by procedure success rates and duration. We found that BBPS scores increased from 4.4 to 7.9 when using the device. Technical success was achieved 78.3% of the time (36/46 cases). Median colonoscopy duration was 46 minutes, although there was a trend toward shorter procedures over time. This is the first clinical evaluation of the third generation of an intraprocedural cleansing device. We found the device efficacious and easy to use with low procedure failure rates, but it does come with a learning curve. We suspect that adoption of this device mutually will benefit patients and health systems with the potential to improve resource utilization.

Colonoscopy Utilization in Elderly Patients with Dementia: Characteristics, Complications, and Charges in a National Matched-Cohort Analysis

BACKGROUND

It is projected that the elderly population will continue to increase. Many will develop chronic conditions such as dementia.

AIMS

Our aims are to describe the utilization of colonoscopy among patients with dementia and compare outcomes in those with and without dementia.

METHODS

This population-based analysis utilized the National Inpatient Sample (NIS) during 2019. Patients with dementia over the age of 60 years receiving colonoscopy were identified utilizing ICD-10 codes. Logistic regression was used for propensity score matching between the comparison groups. A Greedy one-to-one matching algorithm was utilized along with standardized mean differences to assess balance. Mcnemar test, signed rank sum, and paired t-test were used to compare the outcomes.

RESULTS

Initially, 50,692 patients without dementia were compared with 4323 patients with dementia. Patients with dementia were more likely to be female, older, less likely White, had lower income, and more likely to be on Medicare. In the matched comparison (4176 in each group), complication analysis showed that patients with dementia did not have higher colonoscopy-related complications. They did have higher rates of other complications including renal/AKI (p = 0.0042), pulmonary/pneumonia (p = 0.003), cerebrovascular accidents (p = 0.0063), and sepsis (< 0.0001). Patients with dementia were also less likely to have routine discharges (< 0.0001), had longer hospital stays (< 0.0001), and higher hospital costs (< 0.0001).

CONCLUSIONS

Elderly patients with dementia have similar colonoscopy-related complications as patients without dementia. However, they do have higher complications in general. The decision whether to perform colonoscopy in this patient population is multifactorial. A careful assessment of a dementia patient's history can help with this decision.

Importance of Bowel Habits in Predicting Inadequate Bowel Preparation: A Prospective Observational Study

OBJECTIVES

Inadequate bowel preparation (BP) negatively affects the efficacy and quality of colonoscopy. Although constipation has already been reported as one of the most important predictors of inadequate BP, there is limited information on the relation between inadequate BP and bowel habits including constipation-related symptoms, medications, and severity of constipation.

METHODS

This single-center, prospective observational study was conducted between August 2019 and May 2020. All participants answered questionnaires regarding personal bowel habits and received low-volume polyethylene glycol plus ascorbic acid for outpatient colonoscopy. Severity of constipation was evaluated by constipation scoring system. Bowel preparation cleansing was evaluated using Boston Bowel Preparation Scale (BBPS). Potential predictors of inadequate BP were analyzed using multivariate logistic regression models.

RESULTS

Overall, 1054 patients were enrolled, of which, 105 (10%) had inadequate BP (total BBPS ≤ 6 or any segmental BBPS < 2). The risk of inadequate BP increased with constipation severity (P = 0.01). Multivariate analysis showed that frequent straining (> 25% of defecations) (OR 2.09, 95% CI: 1.33-3.28) and chronic use of stimulant laxatives (OR 2.57, 95% CI: 1.59-4.17) were significant predictors of inadequate BP, among personal bowel habits.

CONCLUSION

Frequent straining and chronic use of stimulant laxatives were predictors of inadequate BP. An intensified preparation regimen should be considered for severely constipated patients with straining and chronic use of stimulant laxatives.

Endoscopic Disease Activity and Biologic Therapy Are Independent Predictors of Suboptimal Bowel Preparation in Patients with Inflammatory Bowel Disease Undergoing Colonoscopy

BACKGROUND AND AIMS

Optimal bowel preparation (BP) is critical for endoscopic assessment of inflammation and dysplasia in patients with inflammatory bowel disease (IBD). Comorbidities and patient-related factors have been associated with suboptimal BP (SOBP) in the general population. We sought to identify disease-specific characteristics that may impact the quality of BP in patients with IBD.

METHODS

We conducted a retrospective analysis of adult IBD patients who underwent outpatient colonoscopies between January 2014 and September 2020 at a large academic medical center. Quality of BP was documented using the Boston Bowel Preparation Scale (BBPS) or the Aronchick scale and dichotomized into "suboptimal" (BBPS 0-5 or Aronchick "fair," "poor," unsatisfactory") and "optimal" (BBPS 6-9 or Aronchick "excellent," "good"). IBD-specific and other factors associated with SOBP were evaluated using logistic regression analyses.

RESULTS

Among a total of 395 IBD patients [54% males, mean age 40 years, 63% with Crohn's disease (CD), 35% with ulcerative colitis (UC)], 24.8% had SOBP. On multivariable analysis, moderate-to-severe endoscopic disease vs mild or inactive disease was associated with a higher odds of SOBP [adjusted OR 2.7(95% CI 1.52-4.94)], whereas baseline biologic use was associated with a lower odds of SOBP [aOR 0.24(0.09-0.65)] among the overall IBD cohort. Additionally, age > 65 years [aOR 2.99(1.19-7.54)] and single-dose vs split-dose BP [aOR 2.37(1.43-3.95)] were predictors of SOBP. In the subgroup analysis by IBD type, moderate-to-severe endoscopic disease predicted SOBP among both CD and UC cohorts.

CONCLUSION

Endoscopic disease activity was predictive of SOBP, and biologic therapy was protective against SOBP among IBD patients.

The Patient Experience of an Inadequate-Quality Bowel Preparation During the Colonoscopy Process: A Qualitative Study

As many as 35% of patients may experience an inadequate-quality bowel preparation for colonoscopy, which may then require a repeated colonoscopy without insurance coverage. To our knowledge, there have been no qualitative studies with an in-depth exploration of patient experiences of this outcome. This study aimed to explore patients' perceptions of experiencing an inadequate preparation compared to those with only an adequate-quality bowel preparation history. Quantitative analyses were conducted for three one-item questions (e.g., anxiety rating) with ordinal scales. Qualitative data were collected from audio-recorded and transcribed telephone interviews ( N = 20) and anonymous online surveys ( N = 59). An inductive/deductive coding system was constructed, and themes were generated to form a conceptual framework. Brief quantitative results are provided. Themes of the colonoscopy process include context, prepreparation, implementation, outcomes, response, and decision to repeat. This novel study underscored the emotional experience of patients with inadequate preparation and subsequent influence on decisions to repeat the procedure. Recommendations are given for research, policy, and practice.

Predictors of poor bowel preparations and colonoscopy cancellations in inpatient colonoscopies, a single center retrospective study

BACKGROUND

An adequate bowel preparation prior to colonoscopy is a major quality-limiting factor that determines both the diagnostic and therapeutic yield of a colonoscopy. Colonoscopy is considered the gold standard for colon cancer screening and it is the primary approach to the workup of hematochezia, diarrhea and iron deficiency anemia (IDA). Several modifiable factors of bowel prep adequacy have been identified, that account for around 25% of inadequate bowel preparations in outpatient colonoscopies. However, the literature is sparse when examining the factors associated with inadequate preparations and procedure cancellations in an inpatient hospital setting. We aim to identify factors that affect bowel preparation adequacy and procedure cancellations among diagnostic colonoscopies performed during hospitalization.

METHODS

We retrospectively reviewed the electronic medical records of 1,500 consecutive patients who had a diagnostic colonoscopy as an inpatient at a tertiary level hospital over a 2-year period. All patients were administered a clear liquid diet the day prior to the colonoscopy. Patients were then instructed to drink 4 L of polyethylene glycol (PEG, Golytely) between 5 am to 9 am on the day of the procedure. The clinical course of each case was followed to identify quality of preparations, cancelled procedures and the reasons for cancellations. We applied univariate and multivariate logistic regression analysis to identify variables to predict cancellation and poor preparation.

RESULTS

A total of 1,029 patients were included in the study. 194 (18.8%) patients had colonoscopy cancellations and 268 (26.0%) had poor bowel preparations. Multivariate analysis revealed these factors to be associated with colonoscopy cancellations: education at the graduate school level [odds ratio (OR) =1.93, P=0.04], Hispanic ethnicity (OR =0.47, P<0.01), hemoglobin level <10 g/dL (OR =1.41, P=0.05) and if the colonoscopy was done for other indications (OR =0.53, P=0.04). Factors associated with poor bowel preparation on multivariate analysis, were dementia (OR =2.44, P=0.02), gastroparesis (OR =3.97, P=0.01) and inpatient opioids use (OR =1.69, P=0.04).

CONCLUSIONS

The rate of colonoscopy cancellations and poor bowel preparations in inpatient colonoscopies were high, and we were able to identify predictors of inadequate colon preparation and procedure cancellations. Exploring more individualized colon preparation regimens based on personal risk factors could reduce the number of inadequate and cancelled colonoscopies in an inpatient setting.

Volume of fluid consumption during preparation for colonoscopy is possibly the single most important determinant of bowel preparation adequacy

Background

The effectiveness and safety of colonoscopy are directly dependent on the quality of bowel preparation. Multiple risk factors for inadequate bowel preparation (IBP) have been identified; however, IBP is still reported in 20-30% of cases in most studies. We aimed to identify modifiable predictors of the adequacy of bowel preparation using sodium picosulfate, and to recommend easily modifiable parameters to increase the success rate of colonoscopies.

Methods

This was a single-center observational study of adult outpatients referred for an elective colonoscopy. Patients were interviewed prior to colonoscopy; volume of liquids consumed was calculated as number of 200-mL cups showed to the patient. Additional information, including medical history, diagnoses and regular medications, was procured from patients’ medical records. Univariate and multivariate regression analyses were performed to identify factors significantly associated with IBP in a subgroup analysis of high-risk patients.

Results

The rate of IBP in 1172 subjects was 19.4%. This rate decreased as fluid consumption increased, with a further drop associated with shorter intervals from end of preparation to colonoscopy. Drinking < 1.4 L significantly increased the risk of IBP (odds ratio [OR] 3.62, 95% confidence interval [CI] 2.65-4.95), while drinking ≥2 L was associated with adequate preparation (OR 0.09, 95%CI 0-0.42). These associations were stronger in high-risk individuals.

Conclusion

Greater fluid intake and short interval to colonoscopy are easily modifiable parameters that can substantially reduce the rate of IBP, especially among high-risk individuals.

Bowel-cleansing efficacy of the 1L polyethylene glycol-based bowel preparation NER1006 (PLENVU) in patient subgroups in two phase III trials

BACKGROUND

Adequate bowel preparation prior to colonoscopy is essential for visualization of the colonic mucosa to maximize adenoma and polyp detection. The risk of inadequate bowel cleansing is heightened if the patient is older, male, overweight, and has comorbidities, such as diabetes. This post hoc analysis of the combined MORA and NOCT clinical trials explores the efficacy of evening/morning split-dose regimens of NER1006 (PLENVU^®, Norgine Ltd), a 1-liter polyethylene glycol (PEG) bowel preparation, to evaluate its bowel-cleansing efficacy in patients at risk for inadequate cleansing.

METHODS

Patients requiring colonoscopy were randomized to receive evening/morning split-dosing of either NER1006, 2-liter (2L) PEG and ascorbate, or oral sulfate solution (OSS). Bowel-cleansing efficacy was assessed by treatment-blinded central readers using the validated Harefield Cleansing Scale (HCS).

RESULTS

Split-dose NER1006 was associated with high levels of cleansing, ranging between 87.0% and 94.0% across all patient subtypes (n = 551), including patients with obesity or diabetes. However, patients aged >65 years and <45 years showed significantly greater rates of successful cleansing than patients aged 45-65 years (94.0% versus 94.2% versus 87.0%, p = 0.002). The high-risk patient subgroup, which included obese males aged ⩾60 years, had significantly improved overall and high-quality bowel-cleansing success rates of 100% (33/33) and 72.7% (27/33) on the HCS with NER1006, compared with 86.7% (26/30) and 50% (15/30) with the comparator solutions (p = 0.015 and p = 0.033, respectively). In this high-risk subgroup, adenoma detection was greater per patient receiving NER1006 versus the comparator group (1.82 versus 0.93, p = 0.041). NER1006 was the only treatment that enabled the detection of patients with ⩾5 adenomas [9.1% (3/33) versus 0/30, p = 0.047].

CONCLUSION

NER1006 effectively cleansed a broad range of patients and offered superior bowel cleansing versus 2LPEG/OSS in patients at increased risk of colorectal cancer. Future research should establish whether more effective cleansing also enables improved adenoma detection.

PLAIN LANGUAGE SUMMARY

A low-volume bowel preparation solution to better detect lesions associated with colorectal cancer during colonoscopyColorectal cancer (CRC) is the fourth most commonly diagnosed cancer in the world. Obese men over the age of 65 years are at particularly increased risk of developing CRC. If the changes in their large intestine (colon) could be seen more clearly during a colonoscopy (where a small camera is inserted via the anus to examine the bowels from the inside), patients who need treatment would be diagnosed earlier, thus improving their chances of survival. In this paper we discuss the use of a bowel preparation solution that is more convenient for patients (less to drink) but also cleans bowels more effectively, meaning more lesions are detected than when other solutions are used. This improved cleansing, and thus better visualization, occurred in a range of patients, including those at higher risk of CRC, such as older, overweight men.

Prospective single-blinded single-center randomized controlled trial of Prep Kit-C and Moviprep: Does underlying inflammatory bowel disease impact tolerability and efficacy?

BACKGROUND

Colonoscopy remains the gold standard for detection of colonic disease. An optimal evaluation depends on adequate bowel cleansing. Patients with inflammatory bowel disease (IBD), require frequent endoscopic assessment for both activity and dysplasia assessment. Two commonly used bowel preparations in Australia are Prep Kit-C (Pc) and Moviprep (Mp). Little is known about tolerability, efficacy and safety of split protocols of Mp and Pc in both IBD and non-IBD patients.

AIM

To primary aim was to compare the tolerability, efficacy and safety of split protocols of Mp and Pc in patients having a colonoscopy. The secondary aim was to compare the efficacy, tolerability and safety of either preparation in patients with or without IBD.

METHODS

Patients were randomized to Pc or Mp bowel preparation. Patients completed a questionnaire to assess tolerability. Efficacy was assessed using the Ottawa Bowel Preparation Score. Serum electrolytes and renal function were collected one week prior to colonoscopy and on the day of colonoscopy.

RESULTS

Of 338 patients met the inclusion criteria. Of 168 patients randomized to Mp and 170 to Pc. The efficacy of bowel preparation (mean Ottawa Bowel Preparation Score) was similar between Mp (5.4 ± 2.4) and Pc (5.1 ± 2.1) (P = 0.3). Mean tolerability scores were similar in Mp (11.84 ± 5.4) and Pc (10.99 ± 5.2; P = 0.17). 125 patients had IBD (73 had Crohn’s Disease and 52 had Ulcerative colitis). Sixty-four IBD patients were allocated to Mp and 61 to Pc. In non-IBD patients, 104 were allocated to Mp and 109 to Pc. The mean tolerability score in the IBD group was lower than the non-IBD group (mean tolerability scores: IBD: 10.3 ± 5.1 and non-IBD: 12.0 ± 5.3; P = 0.01). IBD patients described more abdominal pain with Mp when compared with Pc; (Mp: 5.7 ± 4.4 vs Pc: 3.6 ± 2.6, P = 0.046). Serum magnesium level increased with Pc compared with Mp in all patients (mean increase in mmol/L: Mp: 0.03 ± 0.117 and Pc: 0.11 ± 0.106; P < 0.0001).

CONCLUSION

In this study, the efficacy, tolerability and safety of Mp and Pc were similar in all patients. However, patients with IBD reported lower tolerability with both preparations. Specifically, IBD patients had more abdominal pain with Mp. These results should be considered when recommending bowel preparation especially to IBD patients.

An Evidence-based Approach Towards Targeted Patient Education to Improve Bowel Preparation for Colonoscopy

GOALS AND BACKGROUND

Quality of bowel preparation is an important factor influencing adenoma detection. Patient education is believed to improve the quality of bowel preparation but might be resource-intensive. We aimed to (a) identify risk factors for failed bowel preparations and (b) develop and test the efficacy of a screening tool that allows to prospectively identify and target patients at increased risk.

STUDY

Part 1: 76 consecutive outpatients with poor bowel preparation were compared with 76 age-matched and gender-matched outpatients with good preparation from the same procedure lists. Sociodemographic and clinical data were obtained from centralized databases. Univariate analysis and multivariate logistic regression was used to identify risk factors for poor bowel preparation. Part 2: on the basis of results of part 1, a screening tool for prospectively identifying patients at high risk was developed, and targeted education tested.

RESULTS

We identified the use of opioids or other constipating agents and low socioeconomic status as risk factors for poor bowel preparation [odds ratio (OR)=2.88; 95% confidence interval (CI): 1.22-6.80 and OR=2.43; 95% CI: 1.25-4.72]. Diabetes, hypothyroidism, age, and gender were found to have no effect on quality. When education was provided only to patients at increased risk, the targeted approach did not negatively affect the proportion of poor preparation (OR=6.12%; 95% CI: 4.79%-7.78% vs. OR=5.73%; 95% CI: 4.61%-7.10%).

CONCLUSIONS

Poor bowel preparation is associated with specific risk factors. Identifying and specifically targeting education at patients with these risk factors appears to facilitate more efficient use of education resources in endoscopy.

Impact of opioid use on patients undergoing screening colonoscopy according to the quality of bowel preparation

Aims

Constipation associated with opioid therapy for chronic pain may negatively impact colonoscopy success. This retrospective, observational study using administrative data and electronic medical records evaluated the impact of opioid use on colonoscopy outcomes.

Methods and Results

Procedural codes were used to identify patients who had a screening colonoscopy at two Henry Ford Health System centers (January 2015–December 2016). All patients had completed a standard uniform bowel preparation protocol. Medication orders and filled prescriptions were used to identify patients with a history of opioid use during the 28 days preprocedure (exposed) and a matched random sample of presumptive opioid nonusers (unexposed). Electronic medical records were reviewed for colonoscopy procedure data and outcomes.

The exposed and unexposed groups included 964 and 1054 patients, respectively. Inadequate bowel preparation was significantly more common in the exposed versus unexposed group (18.5% vs 12.7%; P < 0.001). In the exposed and unexposed groups, 97.1 and 98.0% of colonoscopy procedures were completed, respectively (P = nonsignificant). Total procedure time was slightly increased for the exposed versus unexposed group (23.8 vs 22.5 min; P = 0.039). Polyp identification and cancer diagnosis were similar between groups. Prolonged sedation occurred in three patients in the exposed group and none in the unexposed group. Procedural complications were rare, but the incidence was significantly greater in the exposed versus unexposed group (1.3% vs 0.2%; P < 0.01).

Conclusions

Opioid exposure was associated with significant reductions in the quality of preprocedure bowel preparation and an increased risk of complications in patients undergoing colonoscopy.

Risk Factors Associated with Inadequate Bowel Preparation in Patients with Functional Constipation

BACKGROUND

Constipation is a common reason of poor bowel preparation, which negatively influences the quality of colonoscopy. Risk factors for inadequate bowel preparation in constipated patients remain unclear.

AIMS

This study aimed to investigate the high-risk factors that might influence the quality of bowel preparation in patients with functional constipation.

METHODS

Consecutive patients with functional constipation who underwent colonoscopy between June 2016 and April 2017 were enrolled. A standard split dose of 4 l polyethylene glycol was used for bowel preparation. Patient- and procedure-related parameters were recorded. The primary outcome was an adequate rate of bowel preparation. Risk factors for inadequate bowel preparation were screened by multivariate logistic regression analysis.

RESULTS

A total of 199 patients were included. Adequate bowel preparation was found in 62.8% (125/199) of patients. At multivariate analysis, Bristol stool form scale (BSFS) 1 [odds ratio (OR) 2.73, 95% confidence interval (CI) 1.26-5.90; P = 0.011], rectal pain score during defecation < 2 (OR 4.14, 95% CI 1.22-13.97; P = 0.022), and starting-to-defecation interval ≥ 4 h (OR 3.83, 95% CI 1.34-10.91; P = 0.012) were risk factors for inadequate bowel preparation in patients with constipation. For patients with no, 1, 2, or 3 risk factors, the rates of inadequate bowel preparation were 11%, 23%, 49%, and 65%, respectively.

CONCLUSIONS

With the standard preparation regime, > 1/3 of patients with functional constipation had inadequate bowel cleansing. BSFS 1, rectal pain score during defecation < 2, and starting-to-defecation interval ≥ 4 h were identified as independent risk factors for inadequate bowel preparation in constipated patients.

TRIAL REGISTRATION

ClinicalTrials.gov number NCT02842411.

A Theory-based Educational Pamphlet With Low-residue Diet Improves Colonoscopy Attendance and Bowel Preparation Quality

GOALS/BACKGROUND

Patients who "no-show" for colonoscopy or present with poor bowel preparation waste endoscopic resources and do not receive adequate examinations for colorectal cancer (CRC) screening. Using the Health Belief Model, we modified an existing patient education pamphlet and evaluated its effect on nonattendance rates and bowel preparation quality.

STUDY

We implemented a color patient education pamphlet to target individual perceptions about CRC and changed bowel preparation instructions to include a low-residue diet instead of the previous clear liquid diet. We compared the nonattendance rate over a 2-month period before and after the introduction of the pamphlet, allowing for a washout period during which pamphlet use was inconsistent. We compared the Boston Bowel Preparation Scale (BBPS) in 100 consecutive patients who underwent colonoscopy during each of the 2 periods.

RESULTS

Baseline characteristics between the 2 groups were similar, although patients who received the pamphlet were younger (P=0.03). The nonattendance rate was significantly lower in patients who received the pamphlet (13% vs. 21%, P=0.01). The percentage of patients with adequate bowel preparation increased from 82% to 86% after introduction of the pamphlet, although this was not statistically significant (P=0.44). The proportion of patients with a BBPS score of 9 was significantly higher in the pamphlet group (41% vs. 27%, P=0.03). There was no difference in adenoma and sessile serrated adenoma detection rates before and after pamphlet implementation.

CONCLUSIONS

After implementing a theory-based patient education intervention with a low-residue diet, our absolute rate for colonoscopy nonattendance decreased by 8% and the proportion of patients with a BBPS score of 9 increased by 14%. The Health Belief Model appears to be a useful construct for CRC screening interventions.

Predictive factors for inadequate bowel preparation using low-volume polyethylene glycol (PEG) plus ascorbic acid for an outpatient colonoscopy

Low-volume polyethylene glycol (PEG) plus ascorbic acid solutions are widely used for bowel cleansing before colonoscopy. This study aimed to investigate the pre-endoscopic predictive factors for inadequate preparation in subjects receiving low-volume PEG plus ascorbic acid. A prospective study was performed at Gangnam Severance Hospital, Korea, from June 2016 to December 2016. All participants received low-volume PEG plus ascorbic acid solutions for outpatient colonoscopy. The split-dose bowel preparation was administered in subject with morning colonoscopy while same day bowel preparation was used for afternoon colonoscopy. 715 patients were enrolled (mean age 56.1 years, 54.4% male), of which 138 (19.3%) had an inadequate bowel preparation. In multivariable analysis, cirrhosis (OR 4.943, 95% CI 1.191–20.515), low (less than 70%) compliance for three-day low-residual diet (OR 2.165, 95% CI 1.333–3.515), brown liquid rectal effluent (compared with clear or semi-clear effluent) (OR 7.604, 95% CI, 1.760–32.857), and longer time interval (≥2 hours) between last defecation and colonoscopic examination (OR 1.841, 95% CI, 1.190–2.849) were found as an independent predictors for inadequate preparation. These predictive factors may be useful in guiding additional intervention to improve quality of bowel preparation.

Predictive factors of an incomplete examination and inadequate small-bowel cleanliness during capsule endoscopy

AIM

the aim of this study was to determine predictive factors for an incomplete capsule endoscopy and an inadequate small-bowel preparation in capsule endoscopy.

METHODS

predictive factors for an incomplete capsule endoscopy were evaluated. Therefore, all patients with incomplete examinations performed between June 2009 and February 2016 were retrospectively included and compared with all patients with complete procedures performed between January 2014 and February 2016. Predictive factors of an inadequate small-bowel cleanliness were assessed. Therefore, the subset of patients that underwent capsule endoscopy between January 2014 and February 2016, including incomplete examinations, were evaluated. Small-bowel cleanliness was evaluated according to a quantitative index and a qualitative evaluation scale. Data with regard to patient and capsule endoscopy was analyzed.

RESULTS

31 incomplete and 122 complete capsule endoscopies were included in the analysis of predictive factors for an incomplete capsule endoscopy. The degree of dependency (OR = 4.67; p = 0.028), performance of a capsule endoscopy in hospitalized patients (OR = 4.04; p = 0.006) and prior abdominal surgery (OR = 3.45; p = 0.012) were independent predictive factors of an incomplete procedure. 130 patients were included in the analysis of predictive factors for an inadequate small-bowel cleanliness. The mean quantitative index value was 7.3 (s.d. ± 2.3); 41.6% and 58.5% of capsule endoscopies were classified as poor-fair and good/excellent respectively, according to the qualitative evaluation. Independent predictive factors for an inadequate preparation according to the quantitative index included male gender (Beta = -0.79; p = 0.028), small-bowel transit time (Beta = -0.007; p < 0.0001) and cardiac disease (Beta = -1.29; p = 0.001). Associated factors according to the qualitative evaluation included male gender (OR = 0.406; p = 0.027) and small-bowel transit time (SBTT) (OR = 0.993; p < 0.0001).

CONCLUSION

inpatient status, higher degrees of dependency and abdominal surgery are predictive factors for an incomplete capsule endoscopy; male gender and higher small-bowel transit time are predictive factors for an inadequate cleanliness.

Multicentre endoscopist-blinded randomised clinical trial to compare two bowel preparations after a colonoscopy with inadequate cleansing: a study protocol

INTRODUCTION

Inadequate bowel preparation is common and negatively impacts colonoscopy quality. The objective of this study is to compare two bowel preparation regimens in cleansing the colon after an index colonoscopy with failed bowel preparation.

METHODS AND ANALYSIS

This is a phase III, multicentre, randomised clinical trial comparing two bowel preparation regimens after failure to adequately cleanse at the index colonoscopy. Regimen A consists of 4 L split-dose polyethylene glycol electrolyte solution (PEG-ELS) and Regimen B consists of 6 L split-dose PEG-ELS, both preceded by 15 mg of bisacodyl the day before the procedure along with a low-fibre diet 3 and 2 days before the procedure followed by a clear fluid diet starting the day before the procedure. The primary outcome is adequate bowel preparation, defined as a Boston Bowel Preparation Scale (BBPS) score of ≥6 with each segment score ≥2. Secondary outcomes include mean BBPS score, bowel preparation adequacy using the US Multi-Society Task Force on Colorectal Cancer definition, detection rate by polyp subtype, caecal intubation rate, mean Validated Patient Tolerability Questionnaire for Bowel Preparation score, subject willingness to repeat the preparation and faecal incontinence rate.

ETHICS AND DISSEMINATION

The study will be conducted in accordance with Good Clinical Practice guidelines and local institutional standards. Study findings will be disseminated at an international gastroenterology conference and published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT02976805; Pre-results.

What Patients Want in a Smartphone App That Supports Colonoscopy Preparation: Qualitative Study to Inform a User-Centered Smartphone App

Background

The preparation for colonoscopy is elaborate and complex. In the context of colorectal cancer screening, up to 11% of patients do not keep their colonoscopy appointments and up to 33% of those attending their appointments have inadequately cleansed bowels that can delay cancer diagnosis and treatment. A smartphone app may be an acceptable and wide-reaching tool to improve patient adherence to colonoscopy.

Objective

The aim of this qualitative study was to employ a user-centered approach to design the content and features of a smartphone app called colonAPPscopy to support individuals preparing for their colonoscopy appointments.

Methods

We conducted 2 focus group discussions (FGDs) with gastroenterology patients treated at the McGill University Health Centre in Montreal, Canada. Patients were aged 50 to 75 years, were English- or French-speaking, and had undergone outpatient colonoscopy in the previous 3 months; they did not have inflammatory bowel disease or colorectal cancer. FGDs were 75 to 90 min, conducted by a trained facilitator, and audiotaped. Participants discussed the electronic health support tools they might use to help them prepare for the colonoscopy, the content needed for colonoscopy preparation, and the features that would make the smartphone app useful. Recordings of FGDs were transcribed and analyzed using thematic analysis to identify key user-defined content and features to inform the design of colonAPPscopy.

Results

A total of 9 patients (7 male and 2 female) participated in one of 2 FGDs. Main content areas focused on bowel preparation instructions, medication restrictions, appointment logistics, communication, and postcolonoscopy expectations. Design features to make the app useful and engaging included minimization of data input, reminders and alerts for up to 7 days precolonoscopy, and visual aids. Participants wanted a smartphone app that comes from a trusted source, sends timely and tailored messages, provides reassurance, provides clear instructions, and is simple to use.

Conclusions

Participants identified the need for postcolonoscopy information as well as reminders and alerts in the week before colonoscopy, novel content, and features that had not been included in previous smartphone-based strategies for colonoscopy preparation. The ability to tailor instructions made the smartphone app preferable to other modes of delivery. Study findings recognize the importance of including potential users in the development phase of building a smartphone app.

Impact of Colonoscopy Preparation Video on Boston Bowel Preparation Scale Score

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths in the United States and the third most common cancer in men and the second most common cancer among women. Early detection of localized adenocarcinoma and adenomatous polyps helps reduce the mortality related to colon cancer. According to the American Gastroenterological Association, colonoscopy (CSPY) is the gold standard in screening for CRC. To improve the results of screening, the CSPY preparation (prep) needs to be optimal. This study was undertaken to determine whether a supplemental standardized educational video on bowel preparation in the viewer's native language would improve bowel preparation at the time of CSPY. After institutional review board approval, the records of adult patients who presented to the gastroenterology clinic were reviewed. Patients who underwent a CSPY were assigned according to whether they watched a supplemental educational video on CSPY bowel preparation in their native language. This video reflects the same information provided in written and verbal form at the time of CSPY scheduling. Bowel prep was rated by the endoscopist using the Boston Bowel Preparation Scale (BBPS) and quantifies the adequacy of the preprocedure bowel prep. Participant characteristics and BBPS scores were statistically assessed for significant differences. We identified a total of 186 patients, 91 in March 2015 (pre-video intervention) and 95 in March 2016 (post-video intervention). Mean BBPS score was 7.9 and 8.54 for the March 2015 and 2016 group, respectively (p value of .0039). Although there was no statistical difference between the 2 groups with concern to gender and age, the racial makeup and BBPS score were statistically different. Multivariate analysis was performed. There was no interaction between gender or race and year effect to account for any difference in that factors' performance. Thus, it can be implied that there is not a consistent race effect but there is a consistent gender effect with females having higher success rates, regardless of video intervention (p value of .003). After controlling for both gender and race, the year effect is modestly significant (p value of .025), with the post-video subjects having higher prep success rates. A supplemental educational video incorporated into precolonoscopy teaching may provide a standardized method of effectively conveying simple bowel prep instructions in an efficient manner. This study demonstrated that using such a video produced significant results in improving the quality of bowel preparation.

Clear liquid diet before bowel preparation predicts successful chromoendoscopy in patients with inflammatory bowel disease

BACKGROUND AND AIMS

Chromoendoscopy (CE) has been shown to generate both a superior diagnostic yield and dysplasia detection rate than conventional white-light endoscopy and requires a high-quality bowel preparation. The aim of this study was to identify predictors of the ability to perform CE in patients with inflammatory bowel disease (IBD).

METHODS

We performed an observational study of patients with IBD undergoing colorectal cancer surveillance examinations with CE. Same-day colonoscopy surveys were used to collect patient and procedural variables. Multivariate logistic regression was used to establish odds ratios of successful completion of CE.

RESULTS

Eighty-eight patients with IBD were enrolled. We found that patients who did not follow a clear liquid diet before colonoscopy had much lower odds of being able to undergo CE (odds ratio, 0.106; 95% confidence interval, 0.013-0.845; P < .034). Further, we found that previously identified risk factors (older age, history of diabetes mellitus, the timing and split dosing of preparation solution, and procedure time (AM or PM), chronic narcotic use, and history of constipation) for inadequate bowel preparation were not associated with the ability to perform CE.

CONCLUSIONS

Following a clear liquid diet the entire day before the procedure was highly predictive of the ability to perform CE. However, established risk factors for inadequate bowel preparation did not inhibit the ability to perform CE in our population. Endoscopists performing CE should consider recommending that patients follow a clear liquid diet the entire day before their examination.

Which Patient-Related Factors Determine Optimal Bowel Preparation?

PURPOSE OF REVIEW

Adequate bowel cleansing before colonoscopy is a simple concept but the high rate of inadequate or incomplete bowel cleanliness and its consequences have been the subject of many studies, guidelines, and meta-analysis. The complexity resides in all the factors surrounding preparation intake such as type and regimen of bowel preparation, diets, compliance, and also patient-related factors that all influence quality of the bowel preparation. The purpose of this review is to focus specifically on patient-related factors and their challenges. Patients with lower GI bleeding are excluded from this review.

RECENT FINDINGS

Patient factors that may be associated with a poor bowel preparation were searched for in the literature. With regard to patient's characteristics, higher age, male gender, and socio-economic status (lower income, Medicaid, and lower education) were all associated with higher rates of inadequate bowel preparation. Comorbidities such as inflammatory bowel disease (IBD), in-patients, body mass index (BMI), cirrhosis, constipation, and neurological condition as well as some pharmacotherapy were also associated with inadequate bowel preparation. Studies identifying predictive patient factors as well as those studying these patients in particular showed variability in the strength of the patient factor associations. Patients taking tricyclic antidepressant, narcotics, and those with neurological conditions were identified to have a stronger association with worse bowel cleanliness. Those can be implemented with the current recommendations of split-dosing. Identifying individual factors that can impact the quality of bowel cleanliness can be challenging. Some have been well-studied in the literature such as age, in-patient status, or constipation and others such as male gender or higher BMI have required more studies to clearly conclude on any possible association. In many studies, simple recommendations like walking 30 min during the preparation, and additional instructions or support have also been added to instructions to improve motility and compliance.

NEW BOWEL PREPARATION TECHNIQUE FOR COLONOSCOPY: CLINICAL TRIAL COMPARING AQUANET AND MANNITOL

Background:

Fifty-five percent of Americans aged 50-65 are submitted to colonoscopy. For over 65-year, this number increases to 64%. In Brazil, it is forecast that the population submitted to colonoscopy will grow, even though inadequate preparation is still a major problem.

Aim:

To analyze the quality of a new intestinal preparation technique, Aquanet EC-2000^®, compared to oral Mannitol solution.

Methods:

This prospective longitudinal study enrolled 200 patients with indication for colonoscopy. The sample was randomly allocated to two groups of 100; one group received Aquanet EC-2000^® to prepare for colonoscopy and the other Mannitol solution. The Boston scale was used to analyze the results.

Results:

As expected both preparations produced similar results with the bowel cleansing of the different regions of the colon being classified as Boston scale 3 (excellent) in most patients (p>0.05).

Conclusion:

The results of bowel preparation using Aquanet EC-2000^® were similar to using Mannitol solution.

Efficacy and tolerability of 2-L polyethylene glycol with ascorbic acid versus sodium picosulfate with magnesium citrate: a randomized controlled trial

BACKGROUND/AIM

Previous studies comparing 2-L polyethylene glycol (PEG)-based solution with ascorbic acid (PEG/Asc) with sodium picosulfate/magnesium citrate (SP/MC) drew inconclusive results. This study aimed to compare a 2-L-PEG/Asc with SP/MC by split method in bowel cleansing efficacy, tolerability, and safety and to identify factors influencing inadequate bowel preparation.

METHOD

We performed a prospective randomized, endoscopist-blinded, single-center, controlled trial. The Aronchick scale and Ottawa bowel preparation scale (OBPS) were used to evaluate the bowel cleansing efficacy, and patients' tolerability and preferences were assessed by questionnaire.

RESULTS

In total, 223 patients were randomized to receive 2-L-PEG/Asc (n = 109) or SP/MC (n = 114). There was no significant difference in overall bowel cleansing efficacy between the two groups; however, when analyzing by individual segment, mean bowel cleansing efficacy of right colon showed a trend in favor of SP/MC group than in PEG/Asc group (OBPS; 1.55 ± 0.66 vs. 1.74 ± 0.88, P = 0.08). Furthermore, SP/MC was better tolerated than PEG/Asc based on ease of consumption and preference to receive the agents again in the future. Total adverse events were significantly lower in SP/MC group than PEG/Asc group (47.4 vs. 62.4%, P = 0.031). In multivariate analysis, later colonoscopic starting time was the only independent factor predicting inadequate bowel preparation (OR 1.39, 95% CI 1.156-1.692, P = 0.001).

CONCLUSIONS

There was no significant difference in overall bowel cleansing efficacy between PEG/Asc and SP/MC; however, SP/MC showed better tolerability and safety profile than PEG/Asc. The independent factor for inadequate bowel preparation was later colonoscopic starting time when applied split method.

Patient Characteristics Associated With Quality of Colonoscopy Preparation: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Some features of patients are associated with inadequate bowel preparation, which reduces the effectiveness of colonoscopy examination. We performed a systematic review and meta-analysis of the association between patients' sociodemographic characteristics, health conditions, and medications with inadequate bowel preparation.

METHODS

We searched the PubMed, Scopus, and Cochrane Review databases for randomized controlled trials cohort (prospective and retrospective), case-control, and cross-sectional studies published through March 2016. We collected information on study design, study population, and bowel preparation. For each factor, we obtained the odds ratio (OR) for inadequate bowel preparation. We conducted the meta-analyses using the random-effects approach and investigated any identified heterogeneity and publication bias via graphical methods, stratification, and meta-regression.

RESULTS

We performed a meta-analysis of 67 studies, comprising 75,818 patients. The estimated pooled OR for inadequate bowel preparation was small for sociodemographic characteristics: 1.14 for age, and 1.23 for male sex (excluding studies in Asia, which had substantial heterogeneity and publication bias), and 1.49 for low education. The effect of high body mass index differed significantly in studies with mostly female patients (OR, 1.05) vs those with mostly male patients (OR, 1.30) (P = .013 for the difference). ORs for constipation and cirrhosis were heterogeneous; adjusted ORs were larger than unadjusted ORs (1.97 vs 1.29 for constipation and 3.41 vs 1.36 for cirrhosis). Diabetes (OR, 1.79), hypertension (OR, 1.25), stroke or dementia (OR, 2.09), and opioid use (OR, 1.70) were associated with inadequate bowel preparation. History of abdominal surgery (OR, 0.99) did not associate with inadequate bowel preparation. Use of tricyclic antidepressants had a larger effect on risk of inadequate bowel preparation in studies of mostly female patients (OR, 2.62) than studies of mostly male patients (OR, 1.42) (P = .085 for the difference).

CONCLUSIONS

In a systematic review and meta-analysis, we found no single patient-related factor to be solely associated with inadequate bowel preparation. Health conditions and use of some medications appear to be stronger predictors than sociodemographic characteristics.

Aquanet Bowel Cleansing Device Versus Oral Sodium Picosulfate for Pre-Endoscopy Bowel Preparation: Propensity Score Analysis for Interventional Effectiveness Evaluation

Background

Colonoscopy procedures are commonly performed and have high success rates. However, poor or inadequate bowel preparation is one of the most common reasons for a repeated or failed colonoscopy. We therefore performed an observational study followed by propensity score modeling to evaluate and compare the quality of bowel preparation with the use of Aquanet bowel cleansing devices (BCDs) versus the use of oral sodium picosulfate solution.

Methods

We performed a prospective cross-sectional study to compare the quality of pre-endoscopic bowel preparation using a BCD with oral solution. Our major outcome of interest was the quality of bowel preparation as measured through the Boston bowel preparation (BBP) scale. Our main predictor was the method of bowel preparation. The bowel was prepared using either sodium picosulfate or the BCD.

Results

A total of 314 participants were part of this study. The average age of the participants was 54 years and most of the participants were females (81%). Sodium picosulfate was associated with better scores at each segment. After propensity scoring with a 1:1 match and further adjusting for the unbalanced variable (age), we found that despite the apparent superior cleansing performance of sodium picosulfate over the BCD, the difference was not statistically significant.

Conclusion

This study reinforces previous reports regarding the quality, safety and comfort of BCDs, indicating that this technique should be considered for colonoscopy preparation. In the future, randomized controlled trials should be performed to validate these preliminary findings.

Improving the Quality of Inpatient Bowel Preparation for Colonoscopies

BACKGROUND

Hospitalized patients completing bowel preparation for colonoscopy typically have preparations of poorer quality when compared to outpatient populations.

AIMS

Our study aimed to evaluate the effectiveness of a performance improvement program in improving colonoscopy preparation for an inpatient population.

METHODS

We identified a cohort of adult patients (n = 641) undergoing an inpatient colonoscopy during a 12-month period at an academic medical center and compared a multifactor intervention group to a historical baseline group. During this 12-month period, a performance improvement program including use of a dedicated gastrointestinal nurse facilitator, implementation of standardized order sets, and introduction of split bowel preparations in the inpatient setting was made available to the cohort group.

RESULTS

The primary outcome was quality of bowel preparation for colonoscopy as rated by endoscopists using the modified Aronchick scale. When comparing the baseline group to the intervention group, the rate of acceptable preparations, characterized as excellent, good, or adequate, increased from 69.9 to 78.9%, which was statistically significant (p < 0.001).

CONCLUSIONS

A comprehensive performance improvement program improved the quality of colonoscopy preparation among inpatients. The use of a dedicated gastrointestinal nurse facilitator, implementation of standardized order sets, and introduction of split bowel preparations are recommended in the inpatient setting for an effective bowel preparation.

Polyethylene glycol-based bowel preparation before colonoscopy for selected inpatients: A pilot study

OBJECTIVE

To evaluate the impact of a new same-day, low-dose 1-L polyethylene glycol-based (1-L PEG) bowel preparation on the diagnostic rating of selected hospitalized patients and its tolerability, with risk factors for inadequate bowel preparation.

METHODS

A single-center prospective pilot study was conducted with hospitalized patients scheduled for colonoscopy, presenting risk factors for poor bowel preparation, such as bleeding or subocclusive symptoms. The included patients were randomly divided in two groups, which received either a same-day 1-L PEG (group A) or a split-dose 4-L PEG (group B), and performed a colonoscopy within 4 h of the last dose.

RESULTS

In all, 44 inpatients [27 males; mean age 63.5 years (range 20-94 years)] were enrolled. Optimal bowel cleansing was reached in 64% and 55% (P = 0.64) of patients in groups A and B, respectively. The adenoma detection rate was 14% (group A) and 18% (group B) (P = 0.34). A valid diagnosis was reached in 38 (86%) of 44 patients (21 in group A and 17 in group B) after a mean hospitalization of 3 days for group A and 6 days for group B (P = 0.04).

CONCLUSIONS

Our data support the conclusion that the schedule protocol proposed in this study enables a clear diagnosis in most of the inpatients at high risk of poor bowel preparation and no statistical differences were found between the two groups in terms of successful bowel cleansing achieved. Therefore, the same-day, low-dose 1-L PEG bowel preparation could be introduced for selected inpatients.

Preparation regimen is more important than patient-related factors: a randomized trial comparing a standard bowel preparation before colonoscopy with an individualized approach

BACKGROUND

Optimal bowel preparation is one of the most important factors affecting the quality of colonoscopy. Several patient-related factors are known to influence the quality of bowel cleansing but randomized trials in this area are lacking. We aimed to compare an individualized bowel prep strategy based on patient characteristics to a standard preparation regimen.

MATERIAL AND METHODS

We conducted an endoscopist-blinded multicenter randomized control-trial. The Boston Bowel Prep Score (BBPS) was used to assess quality of bowel preparation and a 10 point visual analogue scale to assess patient comfort during bowel prep. Patients were randomised to either the standard regimens of split-dose 4L polyethylene-glycol (group A), split-dose sodium picosulphate/magnesium citrate (group B) or to either of the two depending on their responses to a 3-item questionnaire (individualized preparation, group C).

RESULTS

185 patients were randomized during the study period and 143 patients were included in the final analysis. Patients in the individualized group had a median BBPS of 7 compared to a median of 6 in the standard group (p = 0.7). Also, there was no significant difference in patients' comfort scores, irrespective of study group or laxative regimen. However, on multivariable analysis, a split-dose 4L polyethylene-glycol was an independent predictor for achieving a BBPS>6 (OR 3.7, 95% CI 1.4-9.8), regardless of patient-related factors.

CONCLUSION

The choice of laxative seems to be more important than patient-related factors in predicting bowel cleansing. Comfort during bowel prep is not influenced by the type of strategy used.

Predictors of Suboptimal Bowel Preparation Using 3-l of Polyethylene Glycol for an Outpatient Colonoscopy: A Prospective Observational Study

BACKGROUND

A 3-l polyethylene glycol (PEG) solution provided better bowel cleansing quality than a 2-l solution for outpatient colonoscopy. Predictors of suboptimal preparation using a 3-l PEG have not been previously reported.

AIMS

To investigate the possible predictors of suboptimal bowel preparation using 3-l of PEG.

METHODS

We analyzed a database of 1404 consecutive colonoscopies during a 27-month period at a community hospital. A split-dose PEG regimen was provided for morning colonoscopies, and a same-day PEG regimen was provided for afternoon colonoscopies. The level of bowel cleansing was prospectively scored according to the Boston Bowel Preparation Scale (BBPS). Possible predictors of suboptimal colon preparation, defined as a BBPS score <7, were analyzed using univariate statistics and multivariate logistic regression models.

RESULTS

The mean age of the study population (46.7 % men) was 52.5 years (range 20-80 years, SD 11.1 years), and the majority of patients (77.6 %) underwent morning colonoscopies. A suboptimal bowel preparation was reported in 17.2 % of the observed colonoscopies. In the multivariate regression analysis, constipation (odds ratio [OR] 1.60, 95 % confidence interval [CI] 1.15-2.22), male gender (OR 1.68, 95 % CI 1.25-2.25), obesity (OR 1.76, 95 % CI 1.29-2.41), and inadequate (<80 %) PEG consumption (OR 5.4, 95 % CI 2.67-10.89) were independent predictors of a suboptimal colon preparation.

CONCLUSIONS

This prospective study identified that constipation, male gender, obesity, and inadequate intake of PEG were significant risk factors for suboptimal bowel preparation using a 3-l PEG solution for outpatient colonoscopy. Interventions of optimized colonoscopy preparation should be targeted at these patient populations.

Comparative Study of Three Regimens of Bowel Preparation Before Transabdominal Ultrasonography of the Colon

The objective of the study was to compare the efficacy of three bowel preparation regimens for transabdominal colon ultrasonography. A total of 192 consecutive patients were given one of three regimens (senna, magnesium sulfate or polyethylene glycol electrolyte powder) before ultrasonographic examinations. The cleaning grade (I = emptying; II = filled or filled + empty; III = I or II with some retention; and IV = retention [grades I and II were termed "qualified"]) and cleaning range (A = all seven colon sections were qualified; B = four to six sections were qualified; C = three or less sections were qualified) were evaluated retrospectively. Senna was found more effective than polyethylene glycol in terms of cleaning grade (p < 0.001), qualified rate (p < 0.001) and cleaning range (p = 0.003). Senna was better than magnesium sulfate in cleaning grade (p < 0.001). Our results suggest that senna seems to be the preferred regimen for bowel preparation before transabdominal colonic ultrasonography.

Constipation, fiber intake and non-compliance contribute to inadequate colonoscopy bowel preparation: a prospective cohort study

OBJECTIVE

Adequate bowel preparation is important for colonoscopy. Currently available evidence on the determinants of poor bowel preparation is largely derived from studies in Western countries. We aimed to identify the risk factors for inadequate bowel preparation for colonoscopy in the Chinese population.

METHODS

In this single-center study, patients admitted to the Outpatient Department between March 2013 and December 2015 and had indications for colonoscopy were prospectively enrolled. Questionnaires were administered to the patients. Their characteristics and procedure-related parameters such as procedure time were recorded. Bowel preparation was assessed using Boston bowel preparation scale score.

RESULTS

A total of 409 patients with a mean age of 48.8 ± 12.9 years were enrolled in the study, 60.9% of whom were men. On univariate analysis, poor educational level (P = 0.020), chronic constipation (P = 0.001), taking no physical exercise after medication (P < 0.001), a high-fiber diet during the 24-h period immediately preceding the colonoscopy (P < 0.001), incomplete intake of medication (P < 0.001), the passage of yellow or dark stools before colonoscopy (P < 0.001), waiting time (P = 0.001) and stool frequency after medication (P = 0.048) were significantly associated with inadequate bowel preparation. On multivariate analysis, chronic constipation [odds ratio (OR) 2.05, 95% confidence interval (CI) 1.31-3.23, P = 0.002], incomplete intake of the medication (OR 2.77, 95% CI 1.47-5.21, P = 0.002) and a high-fiber diet within 24 h before colonoscopy (OR 2.15, 95% CI 1.40-3.28, P < 0.001) were independent risk factors for inadequate bowel preparation.

CONCLUSIONS

Chronic constipation, poor compliance with treatment and high-fiber diet were predictors of poor bowel preparation. Patients with these risk factors require more effective strategies for bowel preparation.

Optimizing bowel preparation for colonoscopy: a guide to enhance quality of visualization

Colonoscopy is an important screening and therapeutic modality for colorectal cancer. Unlike other screening tests, colonoscopy is dependent on pre-procedure bowel preparation. If the bowel preparation is poor, significant pathology may be missed. Many factors are known to improve bowel preparation. This review will highlight those factors that may optimize the bowel preparation, including choice of bowel preparation, grading or scoring of the bowel preparation, special factors that influence preparation, and diet prior to colonoscopy that affects bowel preparation. The aim of the review is to offer suggestions and guide endoscopists on how to optimize the bowel preparation for the patients undergoing colonoscopy.