Bowel cleansing before colonoscopy: Balancing efficacy, safety, cost and patient tolerance

Age Matters: Adenoma Detection Rates in Average-risk Screening Patients Aged 45 to 49 Compared With Those Aged 50 to 54

GOALS

This study aims to address gaps in medical knowledge by determining whether adenoma detection rate (ADR) in average-risk screening patients aged 45 to 49 is equivalent to screening patients aged 50 to 54.

BACKGROUND

Current guidelines recommend initiating colon cancer screening at age 45, yet our understanding of the effects of ADR in average-risk individuals among 45- to 49-year-olds is still limited.

STUDY

A retrospective analysis was conducted on records of average-risk screening colonoscopies performed on patients aged 45 to 54 from January 2018 to August 2022. Exclusions were prior diagnoses of colorectal cancer or adenomatous polyps, inflammatory bowel disease, personal or family history of genetic cancer syndromes, incomplete colonoscopy, and inadequate bowel preparation. The primary outcome was ADR in the age 45 to 49 group compared with the age 50 to 54 group.

RESULTS

Of the 3199 average-risk screening colonoscopies performed, 879 and 2116 patients were included in the age 45 to 49 and 50 to 54 groups, respectively. Both groups were predominantly female, White ethnicity, never smokers, and obese. ADR was found to be 27% in the age 45 to 49 group compared with 34% in the age 50 to 54 group (odds ratio 0.70, 90% CI: 0.60-0.83, P -value for equivalence=0.81 w/ margin 0.77 to 1.30).

CONCLUSIONS

The study did not demonstrate equivalent ADR between the 2 age groups, with ADR being substantially lower in the age 45 to 49 group (27% vs. 34%). Despite this, the ADR in the 45 to 49 age range surpasses the established benchmark of 25%, supporting the decision to lower the screening age to 45 years. Ongoing national monitoring is essential to comprehensively evaluate the impact of these updated guidelines.

Deaths and cardiopulmonary events following colorectal cancer screening-A systematic review with meta-analyses

BACKGROUND

Colorectal cancer screening programmes (CRCSPs) are implemented worldwide despite recent evidence indicating more physical harm occurring during CRCSPs than previously thought. Therefore, we aimed to review the evidence on physical harms associated with endoscopic diagnostic procedures during CRCSPs and, when possible, to quantify the risk of the most serious types of physical harm during CRCSPs, i.e. deaths and cardiopulmonary events (CPEs).

METHODS

Systematic review with descriptive statistics and random-effects meta-analyses of studies investigating physical harms following CRCSPs. We conducted a systematic search in the literature and assessed the risk of bias and the certainty of the evidence.

RESULTS

We included 134 studies for review, reporting findings from 151 unique populations when accounting for multiple screening interventions per study. Physical harm can be categorized into 17 types of harm. The evidence was very heterogeneous with inadequate measurement and reporting of harms. The risk of bias was serious or critical in 95% of assessments of deaths and CPEs, and the certainty of the evidence was very low in all analyses. The risk of death was assessed for 57 populations with large variation across studies. Meta-analyses indicated that 3 to 23 deaths occur during CRCSPs per 100,000 people screened. Cardiopulmonary events were assessed for 55 populations. Despite our efforts to subcategorize CPEs into 17 distinct subtypes, 41% of CPE assessments were too poorly measured or reported to allow quantification. We found a tendency towards lower estimates of deaths and CPEs in studies with a critical risk of bias.

DISCUSSION

Deaths and CPEs during CRCSPs are rare, yet they do occur during CRCSPs. We believe that our findings are conservative due to the heterogeneity and low quality of the evidence. A standardized system for the measurement and reporting of the harms of screening is warranted.

TRIAL REGISTRATION

PROSPERO Registration number CRD42017058844.

Comparing Low Volume Versus Conventional Volume of Polyethylene Glycol for Bowel Preparation during Colonoscopy: A Randomised Controlled Trial

Background

Polyethylene glycol (PEG) solution is widely used as a colonoscopic bowel cleaning agent, although some patients are intolerant due to the need for ingesting large solution volumes and unpleasant taste. A low-volume solution may enhance patient tolerability and compliance in bowel preparation. Accordingly, this study compared the effectiveness of two difference PEG volumes for bowel preparation before colonoscopy in terms of bowel cleanliness, completeness of colonoscopy, patient tolerability and colonoscopy duration.

Methods

Using a prospective randomised controlled single-blinded study design, 164 patients scheduled for colonoscopy were allocated to two groups (n = 82 patients in each) to receive either the conventional PEG volume (3 L, control group) or the low volume (2 L, intervention group). The Boston Bowel Preparation Scale (BBPS), a validated scale for assessing bowel cleanliness during colonoscopy, was used to score bowel cleanliness in three colon segments. Secondarily, colonoscopy completeness, tolerability to drinking PEG and the duration of colonoscopy were compared between the groups.

Results

There were no statistically significant differences between the two intervention groups in terms of bowel cleanliness (P = 0.119), colonoscopy completion (P = 0.535), tolerability (P = 0.190) or the amount of sedation/analgesia required (midazolam, P = 0.162; pethidine, P = 0.708). Only the duration of colonoscopy differed between the two groups (longer duration in the control group, P = 0.039).

Conclusion

Low-volume (2 L) PEG is as effective as the standard 3 L solution in bowel cleaning before colonoscopy; however, the superiority of either solution could not be established.

Pre-colonoscopy special guidance and education on intestinal cleaning and examination in older adult patients with constipation

BACKGROUND

The prevalence of constipation in the Chinese population over 60 years of age is 11.5%, and this prevalence increases with age, which seriously affects the quality of life in older adults. Therefore, reducing the incidence of constipation in older adults is necessary to promote a healthy lifestyle as well as biochemical health.

AIM

To explore the value of preoperative guidance and education to improve the effects of bowel cleaning in older adult patients undergoing colonoscopy.

METHODS

In this study, 160 older adult patients with constipation requiring colonoscopy at Shandong Provincial Hospital between January 2019 and March 2021 were selected and randomly divided into a study group and a control group, with 80 patients in each group. The study group received medication guidance and targeted educational guidance before the operation, while the control group received only medication and dietary guidance. The baseline data, colonoscopy duration, bowel preparation compliance, Boston bowel preparation (BBPS) assessment score, intestinal bubble score, the incidence of adverse reactions during bowel preparation, and nursing appointment satisfaction were compared between the two groups.

RESULTS

The colonoscopy duration times and intestinal bubble scores of the study group were shorter than those of the control group, with statistically significant differences. The BBPS scores for the right, left, and interrupted colon in the study group were also higher than those in the control group, and the difference was statistically significant. Additionally, the study group had a higher rate of liquid diet one day before the examination, higher rate of correct bowel-clearing agent dilution method, higher rate of accurate time of ingesting the bowel-clearing agent, and a higher proportion of patients ingesting bowel-clearing agent at the specified time than the control group, with statistically significant differences. The incidence of nausea and vomiting during bowel clearance in the study group was significantly lower than that in the control group. The incidence of abdominal pain, abdominal distension, dizziness, and fatigue was compared between the two groups, but the difference was not statistically significant. The scores of service attitude, detailed notification of dietary precautions, clear and easy-to-understand health educational content, and receiving care and comfort in the study group were significantly higher than those in the control group.

CONCLUSION

Preoperative special guidance and education were shown to significantly improve bowel clearance and compliance and reduce the incidence of adverse reactions in older adult patients with constipation undergoing colonoscopy. These factors are beneficial for improving patient satisfaction with nursing services.

Dedicated staff for patient education improves bowel preparation quality and reduces the cecal intubation time of colonoscopy: A single institution retrospective study

Adequate bowel preparation is an essential part of a high-quality colonoscopy. Recent studies showed that the small-volume bowel cleansing agent Bowklean performs better in terms of tolerability and acceptability. However, its split-dose regimen is sometimes confusing to the patient. To promote Bowklean in Fu Jen Catholic University Hospital, dedicated staff for patient education on bowel preparation were provided by Universal Integrated Corporation (Taiwan), but not in every period because of the clinic room availability and manpower capacity. This provided us an opportunity to compare the quality of colonoscopy between those with and without the dedicated patient education. This study aimed to compare various quality indices between the two groups. We set bowel preparation quality as the primary endpoint, assessed by modified Aronchick scale, and other quality indices including procedure time and adenoma detection rate as the secondary endpoints. We performed a single institution retrospective study. All patients who received colonoscopy from an outpatient setting with Bowklean as the bowel cleansing agent from October 2020 to November 2020 were reviewed. Primary and secondary endpoints were then compared between the conventional group and the dedicated staff group, with StataSE 14 by Wilcoxon rank sum test or logistic regression. Four hundred ten patients were recruited, including 217 patients with dedicated patient education and 193 without. The proportion of bowel preparation quality "Excellent + Good + Fair" was significantly higher in dedicated staff group than conventional group (97.7% vs 93.3%, P = .03; logistic regression coefficient = 1.12). The cecal intubation time was significantly shorter in the dedicated staff group (3.68 ± 2.02 minutes vs 4.52 ± 3.25 minutes, P < .01). After excluding those with polypectomy or biopsy, the total procedure time tended to be shorter in the dedicated staff group (10.2 ± 3.35 minutes vs 9.40 ± 2.43 minutes, P = .06). There was no significant difference regarding adenoma detection rate between the two groups. Our study shows that patient education by dedicated staff can improve bowel preparation quality and has the potential to decrease procedure time. Further large-scale prospective trials are still needed to evaluate if it can also achieve a better adenoma detection rate.

Novel multiplex stool-based assay for the detection of early-stage colon cancer in a Chinese population

BACKGROUND

Stool DNA (sDNA) methylation analysis is a promising, noninvasive approach for colorectal cancer screening; however, reliable biomarkers for detecting early-stage colon cancer (ECC) are lacking, particularly in the Chinese population.

AIM

To identify a novel stool-based assay that can improve the effectiveness of ECC screening.

METHODS

A blinded case-control study was performed using archived stool samples from 125 ECC patients, and 125 control subjects with normal colonoscopy. The cohort was randomly divided into training and test sets at a 1.5:1 ratio. Targeted bisulfite sequencing (TBSeq) was conducted on five pairs of preoperative and postop-erative sDNA samples from ECC patients to identify DNA methylation biomarkers, which were validated using pyrosequencing. By logistic regression analysis, a multiplex stool-based assay was developed in the training set, and the detection performance was further assessed in the test set and combined set. The χ² test was used to investigate the association of detection sensitivity with clinico-pathological features.

RESULTS

Following TBSeq, three hypermethylated cytosine-guanine sites were selected as biomarkers, including paired box 8, Ras-association domain family 1 and secreted frizzled-related protein 2, which differed between the groups and were involved in important cancer pathways. An sDNA panel containing the three biomarkers was constructed with a logistic model. Receiver operating characteristic (ROC) analysis revealed that this panel was superior to the fecal immunochemical test (FIT) or serum carcinoembryonic antigen for the detection of ECC. We further found that the combination of the sDNA panel with FIT could improve the screening effectiveness. In the combined set, the sensitivity, specificity and area under the ROC curve for this multiplex assay were 80.0%, 93.6% and 0.918, respectively, and the performance remained excellent in the subgroup analysis by tumor stage. In addition, the detection sensitivity did not differ with tumor site, tumor stage, histological differentiation, age or sex, but was significantly higher in T4 than in T1-3 stage tumors (P = 0.041).

CONCLUSION

We identified a novel multiplex stool-based assay combining sDNA methylation biomarkers and FIT, which could detect ECC with high sensitivity and specificity throughout the colon, showing a promising application perspective.

[Bowel preparation in patients with Diabetes mellitus: Development of a procedure model]

BACKGROUND

Adequate bowel preparation prior to colonoscopy is the key factor for high quality preparation for colonoscopy. Inadequate preparation can result in prolonged procedure time, incomplete colonoscopy and an increased risk of procedural adverse events. Diabetes mellitus has been identified as a predictor of inadequate colonoscopy bowel preparation. Currently, standard recommendations for diabetes patients before colonoscopy are missing.

METHODS

This review is based on a selective literature search in PubMed and Google Scholar carried out in June 2021. Systematic reviews, guidelines, expert opinions, and recommendations from German and international societies were also considered.

RESULTS

The currently available preparations comprise two different groups: High-, medium- and low- volume polyethylene glycol (PEG) preparations and hyperosmotic agents. So far, a couple of reviews tried to identify outcome related differencies. Results are heterogeneous. In practise, preparation agents and timing of preparation as well as a thorough patient information before the preparation process are considered the most relevant items. In diabetes patients, preinterventional dietary recommendations are of paramount importance.

CONCLUSION

Split dosing of PEG preparations are recommended in diabetes patients with expected motility disorders. Extensive counseling about preparation intake and dietary recommendations should be offered.

Role of fecal calprotection in predicting endoscopic recurrence in postoperative Crohn's disease

BACKGROUND AND AIMS

Fecal calprotectin (fCP) has been shown to correlate with endoscopic disease activity in Crohn's disease (CD). The aim of this study was to evaluate its role in predicting early endoscopic recurrence in postoperative CD.

METHODS

Patients who underwent CD-related intestinal resection with ileocolonic anastomosis were prospectively followed up until ileocolonoscopy was performed around 12 months post-surgery. Endoscopic recurrence (ER) was defined as modified Rutgeerts score i2b or higher. Endoscopic still images were reviewed by 2 independent reviewers blinded to fCP results. Stool specimens were collected 6 months post-surgery and a multivariate logistic regression model was established to explore the predictive value of fCP for ER.

RESULTS

79 patients were included. FCP was significantly associated with endoscopic recurrence (p = .036). A cut-off value of fCP of 267 µg/g at 6 months post-surgery predicted ER with a sensitivity of 61.8% and a specificity of 72.7% (AUC 0.669). A prediction model subsuming age at diagnosis and fCP 6 months post-surgery were significantly associated with ER (fCP at 6 months [p = .007] and age at diagnosis [p = .004], multivariate analysis).

CONCLUSIONS

FCP 6 months after surgery and age at diagnosis predict early ER at 1 year postoperatively. However, the low sensitivity of fCP still suggests the necessity of endoscopy as a gold standard for the assessment of postoperative recurrence of CD.KEY SUMMARYWhat is already known? Fecal calprotectin (fCP) correlates with endoscopic disease activity. Endoscopic recurrence occurs in up to 70% of patients after intestinal resection within 1 year.What are the significant and/or new findings of this study? Fecal calprotectin 6 months post-surgery and age at diagnosis significantly predict endoscopic recurrence at 1 year. Due to low sensitivity fCP cannot replace the necessity of endoscopy for accurate assessment of postoperative recurrence.

Safety and efficacy of sodium picosulfate, magnesium oxide, and citric acid bowel preparation in patients with baseline renal impairment or diabetes: subanalysis of a randomized, controlled trial

BACKGROUND

Selecting a bowel preparation for patients with renal impairment or diabetes requires special consideration. We aimed to describe the effect of baseline renal impairment or diabetes on the safety, efficacy, and tolerability of low-volume sodium picosulfate, magnesium oxide, and citric acid (SPMC) ready-to-drink oral solution bowel preparation.

METHODS

A post hoc secondary analysis was performed from a randomized, assessor-blinded study of SPMC oral solution bowel preparation in participants with mild or moderate baseline renal impairment or diabetes. Primary efficacy endpoint ('responders') was the proportion of participants with 'excellent' or 'good' ratings on a modified Aronchick Scale (AS). Secondary efficacy outcomes were the quality of ascending colon cleansing from the Boston Bowel Preparation Scale (BBPS), and selected results from the Mayo Clinic Bowel Prep Tolerability Questionnaire. Safety assessments included adverse events (AEs), adenoma detection, and laboratory evaluations.

RESULTS

Similar overall colon cleansing was demonstrated in the subgroups, with >85% of participants in any subgroup rated as responders by the AS, and >92% of participant responders by the BBPS. Most participants reported a tolerable bowel preparation, regardless of baseline renal impairment or diabetes history. Safety of SPMC oral solution was similar between all subgroups and the overall cohort. For the mild renal impairment, moderate renal impairment, and diabetes subgroups, respectively, commonly reported, drug-related AEs were nausea (2.6%, 5.3%, 1.4%) and headache (2.2%, 2.6%, 4.3%).

CONCLUSIONS

Ready-to-drink SPMC oral solution demonstrated efficacious colon cleansing in patients with baseline mild/moderate renal impairment or diabetes, with a tolerable bowel preparation reported by most.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03017235.

A multicenter, prospective, inpatient feasibility study to evaluate the use of an intra-colonoscopy cleansing device to optimize colon preparation in hospitalized patients: the REDUCE study

Background

High quality bowel preparation prior to colonoscopy can be difficult to achieve in the inpatient setting. Hospitalized patients are at risk for extended hospital stays and low diagnostic yield due to inadequate bowel preparation. The Pure-Vu System is a novel device intended to fit over existing colonoscopes to improve intra-colonoscopy bowel preparation. The objective of the REDUCE study was to conduct the first inpatient study to evaluate optimization of bowel preparation quality following overnight preparation when using the Pure-Vu System during colonoscopy.

Methods

This multicenter, prospective feasibility study enrolled hospitalized subjects undergoing colonoscopy. Subjects recorded the clarity of their last bowel movement using a 5-point scale prior to colonoscopy. After one night of preparation, all enrolled subjects underwent colonoscopy utilizing the Pure-Vu System. The primary endpoint was improvement of colon cleanliness from baseline to post-cleansing with the Pure-Vu System as assessed by the improvement in Boston Bowel Preparation Scale (BBPS). An exploratory analysis was conducted to assess whether the clarity of the last bowel movement could predict inadequate bowel preparation.

Results

Ninety-four subjects were included. BBPS analyses showed significant improvements in bowel preparation quality across all evaluable colon segments after cleansing with Pure-Vu, including left colon (1.74 vs 2.89; p < 0.0001), transverse colon (1.74 vs 2.91; p < 0.0001), and the right colon (1.41 vs 2.88; p < 0.0001). Prior to Pure-Vu, adequate cleansing (BBPS scores of ≥ 2) were reported in 60%, 62%, and 47% for the left colon, transverse colon, and right colon segments, respectively. After intra-colonoscopy cleansing with the Pure-Vu System, adequate colon preparation was reported in 100%, 99%, and 97% of the left colon, transverse colon, and right colon segments, respectively. Subjects with lower bowel movement clarity scores were more likely to have inadequate bowel preparation prior to cleansing with Pure-Vu.

Conclusions

In this feasibility study, the Pure-Vu System appears to be effective in significantly improving bowel preparation quality in hospitalized subjects undergoing colonoscopy. Clarity of last bowel movement may be useful indicator in predicting poor bowel preparation. Larger studies powered to evaluate clinical outcomes, hospital costs, and blinded BBPS assessments are required to evaluate the significance of these findings.

Trial registration Evaluation of the Bowel Cleansing in Hospitalized Patients Using Pure-Vu System (NCT03503162).

Patient experience with NER1006 as a bowel preparation for colonoscopy: a prospective, multicenter US survey

BACKGROUND

NER1006 (Plenvu®, Salix Pharmaceuticals, Bridgewater, NJ) is a 1 L polyethylene glycol bowel preparation indicated for colonoscopy in adults. A US online survey assessed real-world ease of use and treatment satisfaction in individuals who received NER1006.

METHODS

Adults were recruited from 444 US community gastrointestinal practices and provided a kit number for enrollment into an online survey to be completed within 2 weeks. Survey questions evaluated colonoscopy history and prior bowel preparation(s) prescribed, patient experience during NER1006 administration, and patient satisfaction with the bowel preparation process. A 9-point predefined grading scale was used to evaluate ease of NER1006 preparation and consumption (range, 1 "very difficult" to 9 "very easy"); the perceived importance of volume requirement and clear liquid options (range, 1 "not important at all" to 9 "very important"); and patient satisfaction (range, 1 "not satisfied at all" to 9 "very satisfied").

RESULTS

1630 patients were enrolled, 1606 underwent colonoscopy, and 1598 completed the survey between September 15, 2018 and February 28, 2019. Among 1606 patients who had a colonoscopy, 62.5% were female, and the mean patient age was 54.4 years (range 18-89 years). Most patients (74.7%) did not report a family history of colon cancer, 62.6% had undergone prior colonoscopy, and 64.8% were undergoing colonoscopy for routine colorectal cancer screening. A majority (76.1%) of patients who completed the survey reported that NER1006 was very easy to prepare and take, and 89.9% were very or moderately satisfied with NER1006 overall. Most (97.6%) patients reported consuming all or most of the bowel preparation. Among 1005 patients with previous bowel preparation use, 84.7% indicated that their experience with NER1006 was much better or better (65.3%) or about the same (19.4%) compared with previously used bowel preparations, while only 15.3% rated NER1006 as worse or much worse.

CONCLUSIONS

In this first real-world, US multicenter survey, patient-reported experience with NER1006 as a bowel preparation for colonoscopy was favorable and adherence was high. The majority of patients were very or moderately satisfied with the overall experience and found it much better/better than previously used bowel preparations.

TRIAL REGISTRATION

Not applicable.

Triage May Improve Selection to Colonoscopy and Reduce the Number of Unnecessary Colonoscopies

Implementation of population screening for colorectal cancer by direct colonoscopy or follow-up colonoscopy after a positive fecal blood test has challenged the overall capacity of bowel examinations. Certain countries are facing serious colonoscopy capacity constraints, which have led to waiting lists and long time latency of follow-up examinations. Various options for improvement are considered, including increased cut-off values of the fecal blood tests. Results from major clinical studies of blood-based, cancer-associated biomarkers have, however, led to focus on a Triage concept for improved selection to colonoscopy. The Triage test may include subject age, concentration of hemoglobin in a feces test and a combination of certain blood-based cancer-associated biomarkers. Recent results have indicated that Triage may reduce the requirements for colonoscopy by around 30%. Such results may be advantageous for the capacity, the healthcare budgets and in particular, the subjects, who do not need an unnecessary, unpleasant and risk-associated bowel examination.

Determination of the Effectiveness of Informing With the Guidance of an Education Booklet in Patients Undergoing Colonoscopy-A Randomized Controlled Trial

PURPOSE

The aim of this study was to determine the effect of precolonoscopy information with the guidance of an education booklet on anxiety and bowel preparation adequacy in patients undergoing colonoscopy.

DESIGN

A randomized controlled study.

METHODS

The education group was informed face to face by the researcher with the guidance of the colonoscopy education booklet and provided the education booklet. The control group received usual care.

FINDINGS

The mean state and trait anxiety scores of the patients in the education group were found to be significantly lower than the control group. In the education group, the bowel preparation adequacy was determined to be higher compared with the control group.

CONCLUSIONS

Informing patients with the guidance of the education booklet before the colonoscopy decreased patients' state and trait anxiety levels and increased their bowel preparation adequacy.

Bowel Preparation for Colonoscopy in 2020: A Look at the Past, Present, and Future

PURPOSE OF THIS REVIEW

Colorectal cancer is the third most common cancer in the USA. Colonoscopy is considered the gold standard for colorectal cancer screening and can offer both diagnosis and therapy. The bowel preparation remains a significant barrier for patients who need to undergo colonoscopy and is often cited as the most dreaded aspect of the colonoscopy process. Inadequate bowel preparations still occur in 10-25% of colonoscopies, and this in turn can lead to increased procedural times, lower cecal intubation rates, and shorter interval between colonoscopies. From a quality standpoint, it is imperative that we do what we can to decrease the rate of inadequate bowel preparations. This review will focus on recent data regarding bowel preparation and offers a glimpse into what may be coming in the future.

RECENT FINDINGS

Recent advances in the field have been made to improve tolerability of bowel preparations and allow for more adequate colonoscopies. Newer, lower volume, flavored preparations, the use of adjuncts, and using split-dose preparations all can help with tolerability, compliance, and, in turn, preparation quality. Edible bowel preparations may become available in the near future. Early data on the use of artificial intelligence for assessment of preparation quality has been promising. Additionally, utilization of smartphone technology for education prior to the bowel preparation has also been shown to improve the adequacy of bowel preparations.

CONCLUSIONS

Ongoing efforts to improve the tolerability and palatability of colonoscopy bowel preparations are important from a quality improvement standpoint to ensure the adequacy of colonoscopy. Incorporating patient-specific factors and comorbidities is also an essential aspect of improving the quality of bowel preparation. Leveraging technology to better communicate with and educate patients on the bowel preparation process is likely to play a larger role in the coming years.

The importance of colonoscopy bowel preparation for the detection of colorectal lesions and colorectal cancer prevention

Background and study aims  Colonoscopy for colorectal cancer (CRC) screening has reduced CRC incidence and mortality and improved prognosis. Optimal bowel preparation and high-quality endoscopic technique facilitate early CRC detection. This review provides a narrative on the clinical importance of bowel preparation for colonoscopy and highlights available bowel preparations. Methods  A PubMed search was conducted through June 2019 to identify studies evaluating clinical outcomes, efficacy, safety, and tolerability associated with bowel preparation for CRC screening-related colonoscopy. Results  Selecting the optimal bowel preparation regimen is based on considerations of efficacy, safety, and tolerability, in conjunction with individual patient characteristics and preferences. Available bowel preparations include high-volume (4 L) and low-volume (2 L and 1 L), polyethylene glycol (PEG) solutions, sodium sulfate, sodium picosulfate/magnesium oxide plus anhydrous citric acid, sodium phosphate tablets, and the over-the-counter preparations magnesium citrate and PEG-3350. These preparations may be administered as a single dose on the same day or evening before, or as two doses administered the same day or evening before/morning of colonoscopy. Ingesting at least half the bowel preparation on the day of colonoscopy (split-dosing) is associated with higher adequate bowel preparation quality versus evening-before dosing (odds ratio [OR], 2.5; 95 % confidence interval [CI], 1.9-3.4). Conclusions  High-quality bowel preparation is integral for optimal CRC screening/surveillance by colonoscopy. Over the last 30 years, patients and providers have gained more options for bowel preparation, including low-volume agents with enhanced tolerability and cleansing quality that are equivalent to 4 L preparations. Split-dosing is preferred for achieving a high-quality preparation.

A meta-analysis of randomized controlled trials of the addition of lubiprostone to bowel preparation before colonoscopy

AIM

Adequate bowel preparation is essential to the quality of colonoscopy. We performed a meta-analysis to determine the efficacy and safety of the addition of lubiprostone to the bowel preparation process prior to colonoscopy.

METHODS

Online databases, namely, PubMed, MEDLINE and Cochrane Library, were searched for randomized controlled trials that assessed the additive effect of lubiprostone on the quality of colon preparation in patients undergoing colonoscopy. Each included study was evaluated by the Jadad score to assess the quality of the study. The primary outcome was bowel preparation efficacy, defined as the proportion of patients with an excellent or poor preparation. The secondary outcomes included the length of the colonoscopy, polyp detection, and any adverse effects.

RESULTS

In total, 5 articles published between 2008 and 2016 fulfilled the selection criteria. The addition of lubiprostone to the bowel cleansing process significantly increased the proportion of patients with an excellent preparation (risk ratio [RR] = 1.68, 95% confidence interval (CI): 1.40-2.02, P < .00001) but did not decrease the procedural time or increase the polyp detection rate (mean difference = -0.52, 95% CI: -3.74-2.69, P = .75; RR = 1.16, 95% CI: 0.96-1.42, P = .13, respectively). There was no significant difference in the proportion of patients with any adverse events.

CONCLUSION

The addition of lubiprostone to the bowel preparation regimen prior to colonoscopy is effective and safe.

Can a 1-day clear liquid diet with a split -dose polyethylene glycol overcome conventional practice patterns during the preparation for screening colonoscopy?

BACKGROUND/AIMS

A successful screening colonoscopy is closely linked to the quality of a bowel preparation. In this study, we aimed to determine the impact of a 1-day clear liquid diet (CLD) compared to a 3-day combined diet (CMD) accompanied by a split-dose regimen of polyethylene glycol and electrolyte lavage solution (PEG-ELS) for screening colonoscopy.

MATERIALS AND METHODS

This was a prospective, randomized, endoscopist-blinded study. Patients referred for screening colonoscopy were randomized to four groups as a 1-day CLD+PEG-ELS vs. a 1-day CLD+sulfate free (SF)-PEG-ELS and a 3-day CMD+PEG-ELS vs. a 3-day CMD+SF-PEG-ELS. An assessment of the quality of colon cleaning, tolerability to the preparation, and symptoms related to the preparation were recorded.

RESULTS

A total of 506 patients were enrolled in this study. The quality of bowel preparation was significantly inferior in the CMD+PEG-ELS group than CLD+PEG-ELS (p=0.004) and CMD+SF-PEG-ELS groups (p=0.007). There were no statistical differences among the groups in terms of the polyp detection rate. With respect to an easy rating of diet following and the consumption of laxative, there were no significant differences among the four groups. Gastric fullness and nausea/vomiting were pointed out much more, especially in the SF-PEG-ELS users (p=0.008 and p=0.004, respectively).

CONCLUSION

A 1-day CLD was not inferior to a 3-day CMD for colonoscopy preparation in terms of bowel cleaning, the polyp detection rate, and patient tolerance.

Randomized, double-blinded, placebo-controlled trial evaluating simethicone pretreatment with bowel preparation during colonoscopy

BACKGROUND

The presence of small air bubbles and foam are an impediment to a successful colonoscopy. They impair an endoscopist’s view and diminish the diagnostic accuracy of the study. This has been particularly noted to be of concern with the switch to lower volume polyethylene glycol (PEG) and bisacodyl combination preparation.

AIM

To evaluate the effect of oral simethicone addition to bowel preparation on intraluminal bubbles reduction during colonoscopy.

METHODS

Described is a prospective, randomized, multi-center, double-blinded, placebo-controlled study to evaluate the use of premixed simethicone formulation with split-regimen, low-volume PEG-bisacodyl combination bowel preparation for 168 outpatients undergoing screening, surveillance, and diagnostic colonoscopies. Primary outcome includes evaluation of bubbles during colonoscopy graded using the Intraluminal Bubbles Scale. Secondary outcomes include evaluation of the Boston Bowel Preparation Scale (BBPS), total number of polyps, polyp size differentiation, polyp laterality, adenoma detection, mass detection, cecal insertion time, withdrawal time, and patient-reported adverse events.

RESULTS

Higher Intraluminal Bubbles grades III and IV (less than 75% of the mucosa cleared of bubbles/foam requiring intervention with simethicone infused wash) were detected in the placebo group [Simethicone n = 4/84 vs Placebo n = 20/84 (P = 0.007)]. BBPS total score was 7.42 [standard deviation (SD) = ± 1.51] in the simethicone group and 7.28 (SD = ± 1.44) in the placebo group (P = 0.542) from a total of 9. Significantly higher number of adenomas were detected in the simethicone group (P = 0.001).

CONCLUSION

The addition of simethicone to bowel preparation is well advised for its anti-foaming properties. The results of this study suggest that addition of oral simethicone can improve bowel wall visibility.

The Efficacy of Split-Dose Bowel Preparations for Polyp Detection: A Systematic Review and Meta-Analysis

INTRODUCTION

Split-dose bowel preparation leads to superior colon cleansing for colonoscopy. However, the magnitude of benefit in detecting colonic polyps is uncertain. We performed a systematic review to synthesize the data on whether using a split-dose bowel preparation regimen improves the detection of polyps when compared with other dosing methods or regimen products.

METHODS

We searched MEDLINE, EMBASE, and CENTRAL databases (from the inception to June 2017) for randomized controlled trials that assessed the following: split-dose vs day-before, split-dose vs same-day (as colonoscopy), or different types of split-dose regimens for patients undergoing colonoscopy. We excluded studies limited to inpatients, children, or individuals with inflammatory bowel disease. We compared the number of patients undergoing colonoscopy with recorded detection of polyps, adenomas, advanced adenomas, sessile serrated polyps (SSPs), right colonic adenomas, right colonic polyps, or right colonic SSPs.

RESULTS

Twenty-eight trials fulfilled the inclusion criteria (8,842 participants). Of the seven trials comparing split-dose vs day-before bowel preparation regimens, there was an increased detection rate of adenomas (risk ratio (RR) 1.26, 95% confidence intervals (CIs): 1.10-1.44; 4 trials; 1,258 participants), advanced adenomas (RR 1.53, 95% CI: 1.22-1.92; 3 trials; 1,155 participants), and SSPs (RR 2.48, 95% CI: 1.21-5.09; 2 trials; 1,045 participants). Pooled estimates from 8 trials (1,587 participants) evaluating split-dose vs same-day bowel preparations yielded no evidence of statistical difference. For various split-dose vs split-dose trials, 14 fulfilled the criteria (5,496 participants) and no superior split-regimen was identified.

CONCLUSIONS

Compared with day-before bowel preparation regimens, split-dose bowel preparations regimens increase the detection of adenomas, advanced adenomas, and have the greatest benefit in SSP detection.

Efficacy and safety of a ready-to-drink bowel preparation for colonoscopy: a randomized, controlled, non-inferiority trial

BACKGROUND

We performed a randomized, controlled, assessor-blinded, multicenter, non-inferiority (NI) study to compare the safety and efficacy of a ready-to-drink formulation of sodium picosulfate, magnesium oxide, and citric acid (SPMC oral solution) with a powder formulation (P/MC powder) for oral solution.

METHODS

Eligible participants (adults undergoing elective colonoscopy) were randomized 1:1 to split-dose SPMC oral solution or P/MC powder. The primary efficacy endpoint assessed overall colon-cleansing quality with the Aronchick Scale (AS), and the key secondary efficacy endpoint rated quality of right colon cleansing with the Boston Bowel Preparation Scale (BBPS). Assessments were performed by a treatment-blinded endoscopist. Tolerability was assessed using the Mayo Clinic Bowel Prep Tolerability Questionnaire. Safety assessments included adverse events and laboratory evaluations.

RESULTS

The study included 901 participants: 448 for SPMC oral solution; 453 for P/MC powder. SPMC oral solution demonstrated non-inferiority to P/MC powder {87.7% (393/448) responders versus 81.5% (369/453) responders [difference (95% confidence interval): 6.3% (1.8, 10.9)]}. The key secondary efficacy objective assessing the right colon was also met. According to the prespecified hierarchical testing, after meeting the primary and key secondary objectives, SPMC oral solution was tested for superiority to P/MC powder for the primary endpoint (p = 0.0067). SPMC oral solution was well tolerated. Most common adverse events were nausea (3.1% versus 2.9%), headache (2.7% versus 3.1%), hypermagnesemia (2.0% versus 5.1%), and vomiting (1.3% versus 0.7%) for SPMC oral solution and P/MC powder, respectively.

CONCLUSIONS

Ready-to-drink SPMC oral solution showed superior efficacy of overall colon cleansing compared with P/MC powder, with similar safety and tolerability.[ClinicalTrials.gov identifier: NCT03017235.].

A comparative review of use of sulphate and phosphate salts for colonoscopy preparations and their potential for nephrotoxicity

Background and study aims  Colonoscopy is a widely used diagnostic procedure which requires prior cleansing of the bowel. Many different bowel cleansing preparations have been developed, all of which have specific advantages and disadvantages. This review compares two low-volume high-osmolarity bowel cleansing preparations, oral phosphate salts and oral sulphate salts, with a particular focus on risk of nephrotoxicity. Patients and methods  An electronic search of the Medline database was performed using the search terms "(phosphates OR sulfates) AND cathartics [MeSH Term] AND kidney" restricted to humans with a cut-off date of December 31, 2016. Results  Introduction of oral phosphate salts offered the advantage of low intake volume and low risk of bowel irritation compared to previous options. However, phosphate salts have been associated with renal toxicity (acute phosphate nephropathy [APN]), thought to arise due to perturbations of calcium and phosphate homeostasis as a consequence of increases in serum phosphate. This results in high concentrations of calcium phosphate in the distal tubule and collecting ducts of the kidney, where it may precipitate. Although APN is rare, it may lead to permanent kidney damage. For this reason, phosphate salts are contraindicated in vulnerable patient groups. As an alternative to phosphate salts, oral sulphate salts have recently been introduced. Because sulphate absorption from the intestinal tract is saturable, serum sulphate concentrations increase only minimally after ingestion. Furthermore, excretion of sulphate in the kidney is not accompanied by calcium excretion and urine calcium levels are unchanged. For these theoretical reasons, use of sulphate salts as bowel cleansing solutions is not expected to lead to calcium precipitation in the nephron. Conclusions  Oral phosphate salts are no longer recommended for routine use as bowel cleansing preparations as they carry significant risk of kidney damage and a safer alternative is available in the form of oral sulphate solutions. To date, use of sulphate salts has not been associated with elevations in serum creatinine or other markers of renal impairment, nor with clinical manifestations of kidney injury. Nonetheless, experience with sulphate salts in everyday practice is limited and physicians should be vigilant in detecting potential safety issues.

Predictors of inadequate bowel preparation for colonoscopy: a systematic review and meta-analysis

The aim of this study was to investigate factors contributing to poor bowel preparation in patients undergoing colonoscopy procedures. We used a reproducible search strategy to identify studies, searching 10 medical databases, including PubMed, Ovid, Medline, and Cochrane Library Database for reports published between 2000 and 2016. Fully published studies, evaluating risk factors for inadequate bowel preparation, were included. Two reviewers independently scored the identified studies for methodology and abstracted pertinent data. Pooling was conducted with both fixed-effects and random-effects models; results were presented from the random effects model when heterogeneity was significant. Odds ratios (OR) estimates with 95% confidence interval were calculated. Heterogeneity was assessed by I statistics. Twenty-four studies with a total of 49 868 patients met the inclusion criteria. Age (OR: -1.20), male sex (OR: 0.85), inpatient status (OR: 0.57), diabetes mellitus (OR: 0.58), hypertension (OR: 0.58), cirrhosis (OR: 0.49), narcotic use (OR: 0.59), constipation (OR: 0.61), stroke (OR; 0.51), and tricyclic antidepressant (TCA) use (0.51), were associated with inadequate bowel preparation. In our sensitivity analysis comparing Western and Asian countries, we found that diabetes, cirrhosis, male sex, history of stroke and TCA use were stronger risk factors for inadequate bowel preparation in Western countries than in Asian countries. We also found that history of stroke, TCA use, and race were risk factors for inadequate bowel preparation in patients receiving conventional bowel preparation compared with those receiving split-dose bowel preparation. Multiple risk factors affect the quality of bowel preparation and specific risk factors can be intervened upon, in different populations, to optimize preparation.

Comparative safety of bowel cleansers: protocol for a systematic review and network meta-analysis

INTRODUCTION

The US Food and Drug Administration has withdrawn the bowel cleansing kit HalfLytely (PEG 3500) with 10 mg bisacodyl tablets due to an increased risk of ischaemic colitis compared with the same kit with only 5 mg bisacodyl. This is of interest in Canada given that the bowel cleansing kit Bi-Peglyte (PEG 3500) with 15 mg bisacodyl is currently approved for use. The objective is to assess the comparative safety of various bowel cleansers with or without bisacodyl, with a primary interest inpolyethylene glycol (PEG)-based and sodium-picosulfate-based products.

METHODS AND ANALYSIS

Given the existing volume of the literature, the review will be conducted in two stages. Stage 1 will consist of a scoping exercise by searching MEDLINE, Embase and the Cochrane Library (up to 21 November 2017) to identify randomised controlled trials, quasirandomised studies and non-randomised studies in which any bowel cleanser regimens were compared among persons undergoing colonoscopy. The outcomes will be mapped to establish a listing of the studies and their comparisons and outcomes currently available in the literature. From this, a data synthesis plan will be determined. In stage 2, a systematic review with meta-analyses will be pursued, focused on the bowel cleanser comparisons and outcomes of interest identified in stage 1. Two reviewers will screen, extract and quality assess the articles. Outcomes of interest include ischaemic colitis, electrolyte imbalances and their consequences, seizures, bowel perforation and patient tolerability. If sufficient data exist and studies are of sufficient homogeneity, network meta-analyses (NMAs) will be performed.

ETHICS AND DISSEMINATION

Ethics approval was not necessary due to study design. Updating the safety profile of bowel cleansers among the generally healthy population undergoing colonoscopy is pertinent given recent approval changes. This will be the first NMA within this population. Policy considerations may be reconsidered to minimise risk during bowel cleanser use.

PROSPERO REGISTRATION NUMBER

CRD42018084720.

Triage for selection to colonoscopy?

Implementation of population screening for colorectal cancer by direct colonoscopy or follow-up colonoscopy after a positive fecal blood test has challenged the overall capacity of bowel examinations. Certain countries are facing serious colonoscopy capacity constraints, which have led to waiting lists and long-time latency of follow-up examinations. Various options for improvement are considered, including increased cut-off values of the fecal blood tests. Results from major clinical studies of blood-based, cancer-associated biomarkers have led to focus, however, on a triage concept for improved selection to colonoscopy. The triage test may include subject age, concentration of hemoglobin in a feces test and a combination of certain blood-based cancer associated biomarkers. Recent results have indicated that triage may reduce the requirements for colonoscopy by around 30%. Such results may be advantageous for the capacity, the heath budgets and in particular, the subjects, who do not need an unnecessary, unpleasant and risk-associated bowel examination.

Comparative efficacy of combination of 1 L polyethylene glycol, castor oil and ascorbic acid versus 2 L polyethylene glycol plus castor oil versus 3 L polyethylene glycol for colon cleansing before colonoscopy: Study protocol of a randomized, double-blind, single-center study

Colonoscopy has been regarded as an important method of early diagnosing and treating gastrointestinal lesions; however adequate bowel preparation is critical one of many factors needed for successful colonoscopy. Although several modified or novel regimes have been developed, desired quality of bowel preparation has not yet been generated. Scattered evidences revealed that castor oil may have potential of effectively cleansing colon. It is noted that, however, prospective trial of exploring the value of castor oil in preparing bowel before colonoscopy is lacking. The aims of this study are to test the hypotheses that low dose castor oil (30 mL) may enhance potential of polyethylene glycol (PEG) and combination of low castor oil and ascorbic acid may halve the volume of PEG.This is a randomized, double-blind (endoscopist and assessor), single center trial with three-arm design. We will randomly assign 282 adult patients (≥18 years but < 75 years), who are scheduled to undergo colonoscopy, to receive either 3 L PEG alone, 2 L PEG plus 30 mL castor oil or combination of 1 L PEG, 30 mL castor oil and 5 g ascorbic acid. The bowel preparation quality based on Boston Bowel Preparation Scale (BBPS) is the primary outcome. The secondary outcomes include the first defecation time, total number of defecation, time of cecal intubation, detection rate of polyp and adenoma, willing to repeat the same regime, tolerance to regime, and adverse events.The study protocol has been approved by the Clinical Research Ethics Committees of Chongqing University Cancer Hospital & Chongqing Cancer Institute & Chongqing Cancer Hospital & Chongqing Cancer Center (2017[107]). The results from this trial will be submitted for publication in peer-reviewed journals, and will be presented at national and international conferences.

Same-Day Single Dose of 2 Liter Polyethylene Glycol is Not Inferior to The Standard Bowel Preparation Regimen in Low-Risk Patients: A Randomized, Controlled Trial

OBJECTIVES

Split dose of 4 l polyethylene glycol (PEG) is currently the standard regimen for bowel preparation (BP). However, it may be unnecessary for patients without high risks (e.g., old age, constipation, and diabetes, and so on) for inadequate BP. The study aimed to compare the efficacy of bowel cleansing between low-risk patients receiving same-day, single dose of low-volume (SSL) PEG vs. standard regimen.

METHODS

This prospective, randomized, observer-blinded, non-inferiority study enrolled low-risk patients in three centers. Patients undergoing colonoscopy were randomized (1:1) to the SSL or standard group. The primary outcome was adequate BP, defined by Boston Bowel Preparation Score (BBPS) ≥6 and each segmental score ≥2. Secondary outcomes included adverse events, cecal intubation rate, and patient willingness to repeat BP, and so on.

RESULTS

Among 2,532 patients eligible for the study, 940 (37.1%) were at low risk and 792 (31.3%) at high risk for inadequate BP. The low-risk patients were randomly allocated to the SSL (n=470) or standard group (n=470). The baseline characteristics of the two groups were similar. Intention-to-treat analysis showed that adequate BP was achieved in 88.1% in the SSL group and 87.0% in the standard group (relative risk (RR) 1.10, 95% confidence interval (CI): 0.75-1.63, P=0.621). The overall BBPS was 7.3±1.2 and 7.3±1.3, respectively (P=0.948). No significant differences were found between the two groups with regards to the right, transverse, and left-segmental colon BBPS (all P>0.05). However, in terms of adverse events, patients in the SSL group reported less nausea (19.6% vs. 29.9%), vomiting (5.3% vs. 11.4%), and abdominal discomfort (2.2% vs. 6.0%) compared with those in the standard group. More patients in the SSL group were willing to repeat BP (94.0% vs. 89.5%, P=0.015).

CONCLUSIONS

For low-risk patients, the SSL regimen was not inferior to the split dose of 4 l PEG for adequacy of BP. Single dose of low-volume regimen had significantly fewer adverse events. This simplified regimen may be preferable in the "easy-to prepare" population.

Serum peptidome profiling for the diagnosis of colorectal cancer: discovery and validation in two independent cohorts

Colorectal cancer (CRC) is one of the most common malignant neoplasms worldwide. Except for the existing fecal occult blood test, colonoscopy and sigmoidoscopy, no widely accepted in vitro diagnostic methods have been available. To identify potential peptide biomarkers for CRC, serum samples from a discovery cohort (100 CRC patients and 100 healthy controls) and an independent validation cohort (91 CRC patients and 91 healthy controls) were collected. Peptides were fractionated by weak cation exchange magnetic beads (MB-WCX) and analysed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Five peptides (peaks at m/z 1895.3, 2020.9, 2080.7, 2656.8 and 3238.5) were identified as candidate biomarkers for CRC. A diagnostic panel based on the five peptides can discriminate CRC patients from healthy controls, with an accuracy of 91.8%, sensitivity of 95.6%, and specificity of 87.9% in the validation cohort. Peptide peaks at m/z 1895.3, 2020.9 and 3238.5 were identified as the partial sequences of complement component 4 (C4), complement component 3 (C3) and fibrinogen α chain (FGA), respectively. This study potentiated peptidomic analysis as a promising in vitro diagnostic tool for diagnosis of CRC. The identified peptides suggest the involvement of the C3, C4 and FGA in CRC pathogenesis.

A Modified Bowel Preparation Regimen for Colonoscopy Providing the Patients' Satisfaction and Convenience

Background

A complete cleansing of the bowel is a critical factor that impacts the diagnostic accuracy of colonoscopies. However, the common bowel preparation regimen of two 45 mL doses of sodium phosphate (2×NaP) often leads to uncomfortable symptoms and subsequently lower patient adherence. To improve patient adherence and satisfaction, we proposed a modified regimen composed of two sennoside tablets and one bottle of NaP (S+NaP) and we then evaluated bowel preparation quality and patient satisfaction.

Material/Methods

A total of 531 patients who underwent colonoscopies at the outpatient coloproctology clinic from January 2016 to December 2016 were retrospectively reviewed. Eligible patients were divided into two groups: S+NaP group (n=93) and 2×NaP group (n=60). We compared bowel preparation quality, adenoma detection rate (ADR), self-reported patient satisfaction scores, and adverse events among the two groups.

Results

Regarding high bowel preparation quality, our results showed that there was no significant difference among the two groups (p=0.775), as well as no significant differences in ADRs (p=0.187). However, a lower proportion of nausea was found in the S+NaP group compared to the 2×NaP group (24.7% versus 41.7%, respectively, p=0.028). In addition, patients in the S+NaP group were more likely to be very satisfied with the regimen compared with patients in the 2×NaP group (odds ratio: 5.58; 95% confidence interval: 2.36–13.213, p<0.001).

Conclusions

Our modified bowel preparation regimen, S+NaP, yielded significantly higher patient satisfaction with less nausea while maintaining similar bowel preparation quality.