Low-residue versus clear liquid diet before colonoscopy: a meta-analysis of randomized, controlled trials

One-day versus three-day low-residue diet bowel preparation regimens before colonoscopy: a meta-analysis of randomized controlled trials

BACKGROUND AND AIM

Although studies have shown that the quality of bowel preparation with low-residue diet (LRD) is as effective as that of clear fluid diet (CLD), there is currently no consensus on how long an LRD should last. The aim of this study was to compare a 1-day versus 3-day LRD on bowel preparation before colonoscopy.

METHODS

A systematic review search was conducted in MEDLINE/PubMed, EMBASE, Web of Science, and Cochrane database from inception to April 2023. We identified randomized controlled trials (RCTs) that compared 1-day with 3-day LRD bowel cleansing regiments for patients undergoing colonoscopy. The rate of adequate bowel preparation, polyp detection rate, adenoma detection rate, tolerability, willingness to repeat preparation, and adverse events were estimated using odds ratios (OR) and 95% confidence interval (CI). We also performed meta-analysis to identify risk factors and predictors of inadequate preparation.

RESULTS

Four studies published between 2019 and 2023 with 1927 participants were included. The present meta-analysis suggested that 1-day LRD was comparable with 3-day LRD for adequate bowel preparation (OR 0.89; 95% CI, 0.65-1.21; P = 0.45; I2 = 0%; P = 0.52). The polyp detection rate (OR 0.94; 95% CI, 0.77-1.14; P = 0.52; I2 = 23%; P = 0.27) and adenoma detection rate (OR 0.87; 95% CI, 0.71-1.08; P = 0.21; I2 = 0%; P = 0.52) were similar between the groups. There were significantly higher odds of tolerability in patients consuming 1-day LRD compared with 3-day LRD (OR 1.64; 95% CI, 1.13-2.39; P < 0.01; I2 = 47%; P = 0.15). In addition, constipation was identified as the independent predictor of inadequate preparation (OR 1.98; 95% CI, 1.27-3.11; P < 0.01; I2 = 0%; P = 0.46).

CONCLUSION

The present study demonstrated that a 1-day LRD was as effective as a 3-day CLD in the quality of bowel preparation before colonoscopy and significantly improved tolerability of patients. In addition, constipation is an independent risk factor of poor bowel preparation, and the duration of LRD in patients with constipation still needs further clinical trials.

Restrictive diets are unnecessary for colonoscopy: Non-inferiority randomized trial

Background and study aims In colonoscopy, preparation is often regarded as the most burdensome part of the intervention. Traditionally, specific diets have been recommended, but the evidence to support this policy is insufficient. The aim of this study was to evaluate the impact of the decision not to follow a restrictive diet on bowel preparation and colonoscopy outcomes. Patients and methods This was a multicenter, controlled, non-inferiority randomized trial with FIT-positive screening colonoscopy. The subjects were assigned to follow the current standard (1-day low residue diet [LRD]) or a liberal diet. The allocation was balanced for the risk of inadequate cleansing using the Dik et al. score. All participants received the same instructions for morning colonoscopy preparation. The primary outcome was the rate of adequate preparations as defined by the Boston Bowel Preparation Scale. Secondary outcomes included tolerability and measures of colonoscopy performance and quality. Results A total of 582 subjects were randomized. Of these, 278 who received the liberal diet and 275 who received the 1-day LRD were included in the intent-to-treat analysis. Non-inferiority was demonstrated with adequate preparation rates of 97.8% in the 1-day LRD and 96.4% in the liberal diet group. Tolerability was higher with the liberal diet (94.7% vs. 83.2%). No differences were found with respect to cecal intubation time, aspirated volume, or length of the examination. Global and right colon average adenoma detection rates per colonoscopy were similar. Conclusions The liberal diet was non-inferior to the 1-day LRD, and increased tolerability. Colonoscopy performance and quality were not affected. (NCT05032794).

SIED-GISCOR recommendations for colonoscopy in screening programs: Part I - Diagnostic

The implementation of FIT programs reduces incidence and mortality from CRC in the screened subjects. The ultimate efficacy for CRC morbidity and mortality prevention in a FIT program depends on the colonoscopy in FIT+ subjects that has the task of detecting and removing these advanced lesions. Recently, there has been growing evidence on factors that influence the quality of colonoscopy specifically withing organized FIT programs, prompting to dedicated interventions in order to maximize the benefit/harm ratio of post-FIT colonoscopy. This document focuses on the diagnostic phase of colonoscopy, providing indications on how to standardise colonoscopy in FIT+ subjects, regarding timing of examination, management of antithrombotic therapy, bowel preparation, competence and sedation.

Optimization of colonoscopy quality: Comprehensive review of the literature and future perspectives

Colonoscopy is crucial in preventing colorectal cancer (CRC) and reducing associated mortality. This comprehensive review examines the importance of high-quality colonoscopy and associated quality indicators, including bowel preparation, cecal intubation rate, withdrawal time, adenoma detection rate (ADR), complete resection, specimen retrieval, complication rates, and patient satisfaction, while also discussing other ADR-related metrics. Additionally, the review draws attention to often overlooked quality aspects, such as nonpolypoid lesion detection, as well as insertion and withdrawal skills. Moreover, it explores the potential of artificial intelligence in enhancing colonoscopy quality and highlights specific considerations for organized screening programs. The review also emphasizes the implications of organized screening programs and the need for continuous quality improvement. A high-quality colonoscopy is crucial for preventing postcolonoscopy CRC- and CRC-related deaths. Health-care professionals must develop a thorough understanding of colonoscopy quality components, including technical quality, patient safety, and patient experience. By prioritizing ongoing evaluation and refinement of these quality indicators, health-care providers can contribute to improved patient outcomes and develop more effective CRC screening programs.

Colon Bowel Preparation in the Era of Artificial Intelligence: Is There Potential for Enhancing Colon Bowel Cleansing?

BACKGROUND AND OBJECTIVES

Proper bowel preparation is of paramount importance for enhancing adenoma detection rates and reducing postcolonoscopic colorectal cancer risk. Despite recommendations from gastroenterology societies regarding the optimal rates of successful bowel preparation, these guidelines are frequently unmet. Various approaches have been employed to enhance the rates of successful bowel preparation, yet the quality of cleansing remains suboptimal. Intensive bowel preparation techniques, supplementary administration of bowel solutions, and educational interventions aimed at improving patient adherence to instructions have been commonly utilized, particularly among patients at a high risk of inadequate bowel preparation. Expedited strategies conducted on the same day as the procedure have also been endorsed by scientific organizations. More recently, the utilization of artificial intelligence (AI) has emerged for the preprocedural detection of inadequate bowel preparation, holding the potential to guide the preparation process immediately preceding colonoscopy. This manuscript comprehensively reviews the current strategies employed to optimize bowel cleansing, with a specific focus on patients with elevated risks for inadequate bowel preparation. Additionally, the prospective role of AI in this context is thoroughly examined.

CONCLUSIONS

While a majority of outpatients may achieve cleanliness with standard cleansing protocols, dealing with hard-to-prepare patients remains a challenge. Rescue strategies based on AI are promising, but such evidence remains limited. To ensure proper bowel cleansing, a combination of strategies should be performed.

Optimizing adenoma detection in screening-related colonoscopy

INTRODUCTION

Screening-related colonoscopy is a vital component of screening initiatives to both diagnose and prevent colorectal cancer (CRC), with prevention being reliant upon early and accurate detection of pre-malignant lesions. Several strategies, techniques, and interventions exist to optimize endoscopists' adenoma detection rates (ADR).

AREAS COVERED

This narrative review provides an overview of the importance of ADR and other colonoscopy quality indicators. It then summarizes the available evidence regarding the effectiveness of the following domains in terms of improving ADR: endoscopist factors, pre-procedural parameters, peri-procedural parameters, intra-procedural strategies and techniques, antispasmodics, distal attachment devices, enhanced colonoscopy technologies, enhanced optics, and artificial intelligence. These summaries are based on an electronic search of the databases Embase, Pubmed, and Cochrane performed on December 12, 2022.

EXPERT OPINION

Given the prevalence and associated morbidity and mortality of CRC, the quality of screening-related colonoscopy quality is appropriately prioritized by patients, endoscopists, units, and payers alike. Endoscopists performing colonoscopy should be up to date regarding available strategies, techniques, and interventions to optimize their performance.

The Colonoscopy Cookbook: Analysis of effect of a recipe resource on quality and experience of bowel preparation in colonoscopy

Background  High-quality bowel preparation for a colonoscopy improves identification of early lesions in the large bowel, decreases procedure time and increases intervals between colonoscopies. Current recommendations advise a low-residue diet in the days leading up to colonoscopy to improve quality of preparation. This study prepared and provided a recipe resource to patients undergoing colonoscopy and assessed the quality of bowel preparation and patient experience. Patients and methods  A "Colonoscopy Cookbook" resource of recipes that comply with the preoperative diet recommendations was created and added to routine preoperative information given to patients undergoing elective colonoscopies at a regional Australian hospital over a 12-month period. Endoscopic reports were reviewed for each case and quality of bowel preparation was classified as "adequate'' or "inadequate". Data collected were compared to a representative local cohort from 2019. Results  Procedure reports from 96 patients who were provided with the resource were compared with 96 patients who were not. Adequate bowel preparation was nine times as likely when the resource was available (odds ratio 8.54, 95 % confidence interval: 2.85 to 25.60, P  < 0.001) compared to when it was not. The patient experience was assessed using a post-procedure survey, which demonstrated a positive experience in recipe preparation. Most patients would use the resource prior to future colonoscopies. Conclusions  Further randomized controlled trials are required to validate this scoping review. Pre-procedure recipe resources may improve quality of bowel preparation in patients undergoing colonoscopy.

2021 Patient Perceptions Regarding Colonoscopy Experience

GOAL

We sought to document patient perceptions in 2021 regarding colonoscopy experience and potential deterrents to repeat colonoscopy.

BACKGROUND AND AIM

Bowel preparation has been previously considered by patients to be the worst part of a colonoscopy.

MATERIALS AND METHODS

We conducted a prospective survey of consecutive patients age 18 years and older who had just completed colonoscopy at 2 outpatient endoscopy centers at a tertiary academic hospital. The short survey was conducted in the recovery area. The main outcome measure was patient perceptions of the worst part of their colonoscopy experience and which factor would most deter them from a future colonoscopy.

RESULTS

Four hundred patients completed the survey of 405 approached. Average patient age was 64 years, and 48% were women. Seventy-five percent of patients used low-volume preparations. Bowel preparation was considered the worst part of colonoscopy by 71% of patients. Women were more likely to choose laxatives as the worst part of a colonoscopy. Bowel preparation was chosen most often (55%) as the most likely deterrent to a future colonoscopy. There were minimal differences in responses between those receiving low-volume versus high-volume (4 L) preparations.

CONCLUSION

Bowel preparation remains the worst part of the colonoscopy experience for patients, and the most likely deterrent to future colonoscopy.

Prepackaged formula low-residue diet vs. self-prepared low-residue diet before colonoscopy: A multicenter randomized controlled trial

Background and aims

Compared with self-prepared LRD, a prepackaged low-residue diet (LRD) can improve patient compliance, but whether it can further improve the quality of bowel preparation is uncertain. The study aimed to compare the application of the prepackaged formula LRD with self-prepared LRD in bowel preparation for colonoscopy.

Methods

A multicenter randomized controlled trial was conducted in 15 centers. The eligible subjects were randomly assigned to one of two groups: the formula LRD group and the self-prepared LRD group. On the day before the colonoscopy, subjects in the self-prepared LRD group were instructed to consume a restricted LRD prepared by themselves, while subjects in the formula LRD group were given six bags of prepackaged formula LRD and instructed to consume them according to their individual need. The primary outcome was an adequate bowel preparation rate. Secondary outcomes mainly included Boston Bowel Preparation Scale (BBPS) scores, dietary restriction compliance rate, tolerance, satisfaction, adenoma detection rate (ADR), and adverse reactions. The trial was registered at ClinicalTrials.gov under the identifier NCT03943758.

Results

A total of 550 subjects were recruited. Compared with the self-prepared LRD group, the formula LRD group showed a higher adequate bowel preparation rate (94.5 vs. 80.4%; P < 0.01), BBPS scores (7.87 ± 1.13 vs. 6.75 ± 1.47; P < 0.01), dietary compliance rate (92.4 vs. 78.9%; P < 0.01), tolerance (P < 0.01 in degree of hunger, intensity of physical strength, and negative influence on daily activities), satisfaction (8.56 ± 1.61 vs. 7.20 ± 2.02; P < 0.01), and ADR (25.6 vs. 16.0%; P < 0.01). There was no significant difference in adverse reactions.

Conclusion

Compared with self-prepared LRD, the formula LRD showed similar safety and higher bowel preparation quality, compliance, and tolerance in bowel preparation. More formula LRDs could be designed according to different dietary habits and ethnic populations, and further researches are warranted to confirm their effect.

Clinical trial registration

https://register.clinicaltrials.gov, identifier: NCT03943758.

Preparing for Colonoscopy in People with Diabetes: A Review with Suggestions for Clinical Practice

People with diabetes have an increased risk of adverse events during the peri-colonoscopy period, including hypoglycemia, lactic acidosis, diabetic ketoacidosis and acute kidney injury. This is secondary to inadequate dietary modification, the bowel preparation and antihyperglycemic agent modification. With the availability of many new diabetes agents, endoscopists need updated guidance. This review of current literature provides a practical approach to antihyperglycemic agent modification in the context of colonoscopy preparation, as well as guidelines on dietary changes, the bowel preparation itself and glucose monitoring.

Key factors for improving adenoma detection rate

INTRODUCTION

Colonoscopy is a fundamental tool in colorectal cancer (CRC) prevention. Nevertheless, one-fourth of colorectal neoplasms are still missed during colonoscopy, potentially being the main reason for post-colonoscopy colorectal cancer (PCCRC). Adenoma detection rate (ADR) is currently known as the best quality indicator correlating with PCCRC incidence.

AREAS COVERED

We performed a literature review in order to summarize evidences investigating key factors affecting ADR: endoscopists education and training, patient management, endoscopic techniques, improved navigation (exposition defect), and enhanced lesions recognition (vision defect) were considered.

EXPERT OPINION

'Traditional' factors, such as split dose bowel preparation, adequate withdrawal time, and right colon second view, held a significant impact on ADR. Several devices and technologies have been developed to promote high-quality colonoscopy, however artificial intelligence may be considered the most promising tool for ADR improvement, provided that endoscopists education and recording are guaranteed.

From advanced diagnosis to advanced resection in early neoplastic colorectal lesions: Never-ending and trending topics in the 2020s

Colonoscopy represents the most widespread and effective tool for the prevention and treatment of early stage preneoplastic and neoplastic lesions in the panorama of cancer screening. In the world there are different approaches to the topic of colorectal cancer prevention and screening: different starting ages (45-50 years); different initial screening tools such as fecal occult blood with immunohistochemical or immune-enzymatic tests; recto-sigmoidoscopy; and colonoscopy. The key aspects of this scenario are composed of a proper bowel preparation that ensures a valid diagnostic examination, experienced endoscopist in detection of preneoplastic and early neoplastic lesions and open-minded to upcoming artificial intelligence-aided examination, knowledge in the field of resection of these lesions (from cold-snaring, through endoscopic mucosal resection and endoscopic submucosal dissection, up to advanced tools), and management of complications.

Efficacy and tolerability of a low-residue diet for bowel preparation: systematic review and meta-analysis

BACKGROUND

Colorectal cancer (CRC) contributes significantly to cancer mortality worldwide. In an effort to reduce the risk of death, detection of polyps through colonoscopy is crucial. The success of the colonoscopy depends on the diet administered the day before the test. Our aim was to evaluate the efficacy, tolerability, and adverse effects of bowel preparation when using a low-residual diet (LRD) compared to a clear-liquid diet (CLD) the day before a scheduled colonoscopy.

METHODS

PubMed/Medline, Embase, the Cochrane Central Register of Controlled Trials (CENTRAL) and Scopus databases were searched. We included studies of patients undergoing a scheduled colonoscopy for CRC screening and surveillance or for diagnostic purposes that compared a LRD with a CLD the day before the colonoscopy. Efficacy, the primary outcome, was evaluated as the rate of adequate bowel preparation. Secondary outcomes were tolerability and adverse effects of bowel preparation.

RESULTS

Thirteen RCTs (N = 2587) were included. Patients receiving a LRD compared to a CLD showed no difference in adequate bowel preparations (RR 1.02; 95% CI 0.99-1.05; I² = 60%). However, the LRD improved patient tolerability (RR 1.17; 95% CI 1.12-1.23; I² = 66%) and had fewer adverse effects (RR 0.89; 95% CI 0.84-0.94; I² = 73%) compared to the CLD. Groups using a LRD with 4L of polyethylene glycol in a single dose or a LRD with < 2000 kcal < 32 g of fibres/day had better tolerability.

CONCLUSION

Based on these findings, our recommendation is strong in favour of a LRD for bowel preparation of patients undergoing a scheduled colonoscopy. This diet could also be useful as a preoperative colonic preparation, but this requires further research.

[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.

Colonoscopy: an evidence-based approach

Colonoscopy is an invasive, endoscopic procedure undertaken to visualise the inner lumen of the colon and is used for a variety of diagnostic purposes. The procedure is increasingly performed by nurse endoscopists. This article provides an overview of the indications and contraindications for colonoscopy and describes various elements of the procedure, including consent, sedation and bowel preparation within the context of the evidence base. The article also discusses patient care before, during and after the procedure.

Efficacy of ultra-low volume (≤1 L) bowel preparation fluids: Systematic review and meta-analysis

BACKGROUND AND AIMS

High-quality bowel preparation is paramount for the diagnostic accuracy and safety of colonoscopy; however, it is often difficult for patients to adhere to high-volume laxatives, which may contribute to poor bowel preparation. This review aims to assess the efficacy of bowel preparation fluids of 1 L or less (≤1 L).

METHODS

We performed a systematic review including all relevant randomized controlled trials on ultra-low volume (≤1 L) bowel preparation fluids for colonoscopy published since 2015. Primary endpoint was the percentage of adequately prepared patients. Secondary endpoints included adenoma detection rate (ADR) and safety.

RESULTS

Bowel preparation with sodium picosulfate/magnesium citrate (SPMC; 19 trials, n = 10,287), 1L-polyethylene glycol with ascorbate (PEGA; 10 trials, n = 1717), sodium phosphate (NaP; 2 trials, n = 621), and oral sulfate solution (OSS; 3 trials, n = 597) was adequate in 75.2%, 82.9%, 81.9%, and 92.1%, respectively, of patients; however, heterogeneity between studies was considerable (I² range: 86-98%). Pooled ADRs were 31.1% with SPMC, 32.3% with 1L-PEGA, 30.4% with NaP, and 40.9% with OSS. Temporary electrolyte changes were seen with all ultra-low volume bowel preparation fluid solutions but without sustained effects in most patients.

CONCLUSION

Ultra-low volume bowel preparation fluids do not always meet the 90% quality standard for adequate bowel preparation as defined by current guidelines. Nonetheless, they may be considered in patients intolerant for higher-volume laxatives and without risk factors for inadequate bowel preparation or dehydration-related complications.

Validation and Application of Predictive Models for Inadequate Bowel Preparation in Colonoscopies in a Tertiary Hospital Population

Background: Bowel preparation is a major quality criterion for colonoscopies. Models developed to identify patients with inadequate preparation have not been validated in external cohorts. We aim to validate these models and determine their applicability. Methods: Colonoscopies between April and November 2019 were retrospectively included. Boston Bowel Preparation Scale ≥2 per segment was considered adequate. Insufficient data, incomplete colonoscopies, and total colectomies were excluded. Two models were tested: model 1 (tricyclic antidepressants, opioids, diabetes, constipation, abdominal surgery, previous inadequate preparation, inpatient status, and American Society of Anesthesiology [ASA] score ≥3); model 2 (co-morbidities, tricyclic antidepressants, constipation, and abdominal surgery). Results: We included 514 patients (63% males; age 61.7 ± 15.6 years), 441 with adequate preparation. The main indications were inflammatory bowel disease (26.1%) and endoscopic treatment (24.9%). Previous surgery (36.2%) and ASA score ≥3 (23.7%) were the most common comorbidities. An ASA score ≥3 was the only identified predictor for inadequate preparation in this study (p < 0.001, OR 3.28). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of model 1 were 60.3, 64.2, 21.8, and 90.7%, respectively. Model 2 had a sensitivity, specificity, PPV, and NPV of 57.5, 67.4, 22.6, and 90.5%, respectively. The AUC for the ROC curves was 0.62 for model 1, 0.62 for model 2, and 0.65 for the ASA score. Conclusions: Although both models accurately predict adequate bowel preparation, they are still unreliable in predicting inadequate preparation and, as such, new models, or further optimization of current ones, are needed. Utilizing the ASA score might be an appropriate approximation of the risk for inadequate bowel preparation in tertiary hospital populations.

Novel frontiers of agents for bowel cleansing for colonoscopy

The incidence of colorectal cancer (CRC) is characterized by rapid declines in the wake of widespread screening. Colonoscopy is the gold standard for CRC screening, but its accuracy is related to high quality of bowel preparation (BP). In this review, we aimed to summarized the current strategy to increase bowel cleansing before colonoscopy. Newly bowel cleansing agents were developed with the same efficacy of previous agent but requiring less amount of liquid to improve patients’ acceptability. The role of the diet before colonoscopy was also changed, as well the contribution of educational intervention and the use of adjunctive drugs to improve patients’ tolerance and/or quality of BP. The review also described BP in special situations, as lower gastrointestinal bleeding, elderly people, patients with chronic kidney disease, patients with inflammatory bowel disease, patients with congestive heart failure, inpatient, patient with previous bowel resection, pregnant/lactating patients. The review underlined the quality of BP should be described using a validate scale in colonoscopy report and it explored the available scales. Finally, the review explored the possible contribution of bowel cleansing in post-colonoscopy syndrome that can be related by a transient alteration of gut microbiota. Moreover, the study underlined several points needed to further investigations.

Comparative Effectiveness of Enhanced Patient Instructions for Bowel Preparation Before Colonoscopy: Network Meta-analysis of 23 Randomized Controlled Trials

Background

Various enhanced patient instructions (EPIs) have been used for bowel preparation (BP) and our previous meta-analysis also demonstrated the efficacy of EPIs in increasing the colonic polyp and adenoma detection rates; however, the optimal method for adequate BP has not yet been developed.

Objective

We performed a network meta-analysis to determine the optimal instructions.

Methods

We searched for randomized controlled trials (RCTs) comparing the effectiveness of EPIs with each other or standard patient instructions (SPIs) for BP. We performed direct and Bayesian network meta-analyses for all instructions and used the GRADE (Grading of Recommendations Assessment, Development and Evaluation) criteria to appraise the quality of evidence.

Results

We included 23 RCTs (7969 patients) comparing 10 different instructions. In direct meta-analyses, most of the EPIs, except visual aids and mobile apps, increased the adequate preparation rate (APR). Network meta-analyses showed that additional explanations were superior to visual aids (odds ratio [OR] 0.35, 95% CI 0.19-0.59), telephone calls (OR 0.62, 95% CI 0.37-0.99), educational videos (OR 0.79, 95% CI 0.5-0.77), and mobile apps (OR 0.33, 95% CI 0.14-0.68) with low-to-high-quality evidence; newly designed booklets (OR 3.28, 95% CI 1.59-6.16), SMS text messaging (OR 2.33, 95% CI 1.28-3.91), telephone calls (OR 1.86, 95% CI 1.03-1.78), educational videos (OR 2.33, 95% CI 1.40-3.65), and social media applications (OR 2.42, 95% CI 1.4-3.93) were superior to visual aids and mobile apps with low-to-high-quality evidence. SMS text messaging, telephone calls, and social media applications increase adherence to and satisfaction with the BP regime. Social media applications reduce the risk of adverse events (AEs). Telephone calls and social media applications increase the polyp detection rate (PDR).

Conclusions

Newly designed booklets, telephone calls, educational videos, and social media applications can improve the quality of BP. Telephone calls and social media applications improve adherence to and satisfaction with the BP regime, reduce the risk of AEs, and increase the PDR.

Trial Registration

INPLASY (International Platform of Registered Systematic Review and Meta-analysis Protocols) INPLASY2020120103; https://inplasy.com/inplasy-2020-12-0103/

Is it time we split bowel preparation for all colonoscopies? Outcomes from a national survey of bowel preparation practice in the UK

Introduction

Adequate bowel preparation is a prerequisite for effective colonoscopy. Split bowel preparation results in optimal cleansing. This study assessed the bowel preparation regimes advised by endoscopy units across the UK, and correlated the differences with outcomes.

Methods

Trusts in the UK were surveyed, with data requested between January 2018 and January 2019, including: the type and timing of preparation, pre-endoscopy diet, adequacy rates and polyp detection. Trusts were grouped according to the timing of bowel preparation. χ² test was used to assess for differences in bowel preparation adequacy.

Results

Moviprep was the first line bowel preparation in 79% of trusts. Only 7% of trusts advised splitting bowel preparation for all procedures, however, 91% used split bowel preparation for afternoon procedures. Trusts that split preparation for all procedures had an inadequacy rate of 6.7%, compared with 8.5% (p<0.001) for those that split preparation for PM procedures alone and 9.5% (p<0.001) for those that provided day before preparation for all procedures. Morning procedures with day-before preparation had a higher rate of inadequate cleansing than afternoon procedures that received split preparation (7.7% vs 6.5 %, p<0.001). The polyp detection rate for procedures with adequate preparation was 37.1%, compared with 26.4% for those that were inadequate.

Conclusion

Most trusts in the UK do not provide instructions optimising the timing of bowel preparation prior to colonoscopy. This correlated with an increased rate of inadequate cleansing. Splitting bowel preparation is likely to reduce the impacts of poor cleansing: missed lesions, repeat colonoscopies and significant costs.

The Prediction of Inadequate Colon Capsule Cleansing: A Cohort Selection Guided by CC-CLEAR

Introduction

In order to optimize the rate of adequate cleansing in colon capsule, it may be important to identify risk factors that can predict a suboptimal colon preparation.

Aim

To define predictive factors for inadequate bowel preparation in colon capsule, according to CC-CLEAR (Colon Capsule CLEansing Assessment and Report).

Methods

Retrospective, single center, cohort study. Patients' demographics, data, and quality of bowel preparation, according to CC-CLEAR, were collected retrospectively. A univariate analysis tested the association between covariables and the outcome, inadequate cleansing. The statistically significant variables were included in multivariable logistic binary regression, and a receiver operating characteristic curve (ROC) assessment was performed.

Results

We included 167 consecutive colon capsules. Sixty-eight percent (n = 114) of patients were female, with a mean age of 64 years. The main indication for colon capsule was previous incomplete colonoscopy, in 158 patients (94.6%). The colon capsules cleansing was graded as good or excellent in 96 patients (57.5%) and as inadequate in 71 (42.5%), according to CC-CLEAR. The variables inadequate previous colon cleansing (OR adjusted 41.72 [95% CI 12.57–138.57], p value < 0.001); chronic laxative (OR adjusted 4.86 [95% CI 1.08–21.79], p value = 0.039); antidepressant (OR adjusted 5.00 [95% CI 1.65–15.16], p value = 0.004), and impaired mobility (OR adjusted 5.54 [95% CI 1.17–26.31], p value = 0.031) were independently associated with the outcome inadequate cleansing, after adjusting for confoundment. The model presented an excellent discriminative power towards the outcome variable (AUC ROC 0.937 [CI 95% 0.899–0.975], p value < 0.001).

Conclusion

A previous inadequate colon cleansing, the use of chronic laxative and antidepressant, or impaired mobility are predictors of inadequate colon capsule cleansing, as assessed by the CC-CLEAR. These 4 predictors come together as a model enabling an accurate categorization of the patients at major risk of inadequate bowel preparation for capsule colonoscopy, with an excellent discriminative power and performance, which seems useful for the selection of patients for tailored optimization of the colon cleansing protocol.

A Systematic Review and Meta-Analysis of Low-Residue Diet Versus Clear Liquid Diet: Which Is Better for Bowel Preparation Before Colonoscopy?

The goal of this systematic review was to compare the clear liquid diet and the low-residue diet to determine which is better for bowel preparation before colonoscopy. A literature search for randomized controlled trials on the effects of employing the clear liquid diet and low-residue diets before colonoscopy was conducted in major online English databases (PubMed, Web of Science, and Ovid EMBASE). After the systematic review of all 16 studies, the outcomes including quality of bowel preparation, tolerance, willingness to repeat, and adverse effects were analyzed through meta-analysis. The statistical analysis was performed by using RevMan 5.3 software. No statistically significant difference was observed between the low-residue diet and clear liquid diet groups (odds ratio [95% confidence interval] = 1.19 [0.79, 1.81]; p = .41). There was no statistically significant difference between the Boston Bowel Preparation Scale (standard mean difference [95% confidence interval] =-0.04 [-0.21, -0.14]; p = .68) Ottawa Bowel Preparation Scale (standard mean difference [95% confidence interval] =-0.04 [-0.19, 0.11]; p = .59) scores of the two groups. The quality indicators for colonoscopy of the two groups were not statistically significant. However, patient tolerance to the low-residue diet was higher (odds ratio [95% confidence interval] = 1.86 [1.47, 2.36]; p < .01). More patients in the low-residue diet group were willing to repeat the low-residue diet for bowel preparation (odds ratio [95% confidence interval] = 2.34 [1.72, 3.17]; p < .01). More patients in the clear liquid diet group experienced hunger, nausea, and vomiting. People who employed the low-residue diet before colonoscopy had the same quality of bowel preparation as those with clear liquid diet. Meanwhile, the tolerance of people with low-residue diet was better than people with clear liquid diet, and these people were more willing to repeat the colonoscopy with less adverse events.

Comparable quality of bowel preparation with single-day versus three-day low-residue diet: Randomized controlled trial

BACKGROUND AND AIMS

There is controversy about the length of low-residue diet (LRD) for colonoscopy preparation. The aim of the study was to compare one-day vs. three-day LRD associated to standard laxative treatment for achieving an adequate colonoscopy preparation in average risk subjects with positive fecal immunochemical test undergoing screening colonoscopy.

METHODS

A non-inferiority, randomized, controlled, parallel-group clinical trial was performed in the setting of average risk colorectal cancer screening program. Participants were randomized to receive 1-day vs. 3-day LRD in addition to standard polyethilenglicol treatment. Adequacy of preparation was evaluated using the Boston Bowel Preparation Scale (BBPS). Primary outcome was achieving a BBPS ≥ 2 in all colon segments. Analysis was performed for a non-inferiority margin of 5%, a 95% statistical power and one-sided 0.05 significance level.

RESULTS

A total of 855 patients were randomized. Adequate bowel preparation was similar between groups: 97.9% of patients in the 1-day LRD group vs 96.9% in the 3-day LRD group achieved the primary outcome (P-value for non-inferiority < 0.001). The percentage of patients with BBPS scores ≥ 8 was superior in the 1-day LRD group (254 vs 221 in the 3-day LRD group, P = 0.032). The 1-day regimen was better tolerated than the 3-day diet. 47.7% (vs 28.7%, P < 0.05) of patients rated the 1-day LRD as very easy to follow.

CONCLUSION

The 1-day LRD is non-inferior to 3-day LRD for achieving an adequate colon cleansing before average risk screening colonoscopy and it is better tolerated.

Impact of Prepackaged Low-Residue Diet on Bowel Preparation for Colonoscopy: A Meta-analysis

This meta-analysis aimed to evaluate the impact of prepackaged low-residue diet (PLRD) on bowel preparation for colonoscopy. We searched PubMed, Web of Science, EMBASE, and Cochrane Library databases from inception to August 2020. Randomized controlled trials (RCTs) comparing PLRD with clear liquid diet (CLD) or self-prepared LRD were considered for inclusion. The analysis calculated the odds ratio (OR) for the rate of adequate bowel preparation, patient tolerance, willingness to repeat bowel preparation, tolerability of bowel preparation, and overall adverse effects. Five RCTs published between 2006 and 2019 (N = 561) were included in our meta-analysis. Compared with the traditional CLD or self-prepared LRD, PLRD showed significantly higher rates of adequate bowel preparation (OR, 2.16; 95% confidence interval [CI], 1.18-3.98; p = .01), patient tolerance (OR, 1.99; 95% CI, 1.30-3.07; p = .002), and willingness to repeat the bowel preparation (OR, 1.68; 95% CI, 1.05-2.70; p = .03), with no differences in adverse events (OR, 0.93; 95% CI, 0.59-1.46; p = .75). Prepackaged low-residue diet improved bowel preparation quality, patient tolerance, and willingness to repeat bowel preparations. Importantly, PLRD does not increase the incidence of adverse events. This suggests that it is effective and safe to use PLRD for bowel preparation before colonoscopy.

Bowel Preparation for Pediatric Colonoscopy

Colonoscopy is an important diagnostic and therapeutic tool in evaluating and treating gastrointestinal tract pathologies. Adequate visualization of the intestinal lumen is necessary for detection of lesions, and thus bowel preparation is a key component of the process. It is estimated that over 25% percent of pediatric patients have sub-optimal bowel preparations, which can lead to longer procedure times, missed pathology, unsuccessful ileal intubation, and possibly repeat procedure/anesthesia. There is no universal protocol for bowel preparation in pediatrics and there is a wide variability of practices around the world. The purpose of this paper is to review the recent published literature regarding bowel preparations for pediatric colonoscopy with focus on published work in the last decade exploring a number of factors involved in bowel preparation including the role of patient education, types of bowel preparation, and their efficacy and safety.

Low-residue versus clear liquid diet before colonoscopy: An updated meta-analysis of randomized, controlled trials

Great value in the early identification and treatment of adenomatous polyps or early canceration using colonoscopy has been recognized. A clear colonoscopic vision brought by good intestinal preparation will become crucial. Several studies have completed using the low-residue diet (LRD) versus a clear liquid diet (CLD) the day before colonoscopy that presenting contradictory results. Therefore, a more comprehensive and updated meta-analysis is needed to summarize the findings on the effects of LRD and CLD on intestinal preparation and the quality of coloscopy.The comprehensive search was performed in PubMed/MEDLINE, Scopus, Cochrane databases (February 2020). LRD vs CLD before colonoscopy were included in this study. Mantel-Haenszel or DerSimonian and Laird models with the relative risk (RR) to evaluate differences in intestinal preparation, tolerance, readiness to repeat preparation, detected of a polyp, and overall adverse reactions.Total 16 studies (N = 3413) were eligible. Patients with LRD compared with CLD indicated significantly better of tolerability (RR 0.92;95% CI,0.85-0.99; P < .05) and willingness to repeat intestinal preparation (RR 0.86; 95% CI 0.79-0.93; P < .05), but no differences with adequate intestinal preparations, detected polyp or overall adverse reactions (all P > .05).Patients with LRD the day before colonoscopy show better tolerance and willingness to repeat intestinal preparation, and no difference with adequate intestinal preparations compared with CLD, but the recommended level of evidence is weak. However, in terms of the detection rate of intestinal adenomas, the LRD group is not weaker than the CLD group, for its evidence level is high, and can significantly reduce the hunger experience of patients.

Colorectal Cancer Screening Decisions in the Opportunistic Setting

Colorectal cancer incidence and mortality have decreased in the United States in recent decades, largely through opportunistic screening. Although certain organizations have improved internal screening rates by implementing programmatic screening, most of the United States undergoes opportunistic screening. Much effort and resources have been expended comparing screening tests to determine the most effective; however, deeper analysis of the US population has revealed subsets of ethnicities may be grossly underscreened. The most effective screening test remains the test that is completed and adhered to, and a better question may concern the best method of discussing screening.

Enhanced Patient Education for Colonic Polyp and Adenoma Detection: Meta-Analysis of Randomized Controlled Trials

Background

To improve patients’ comprehension of bowel preparation instructions before colonoscopy, enhanced patient education (EPE) such as cartoon pictures or other visual aids, phone calls, mobile apps, multimedia education and social media apps have been proposed. However, it is uncertain whether EPE can increase the detection rate of colonic polyps and adenomas.

Objective

This meta-analysis aimed to evaluate the efficacy of EPE in detecting colonic polyps and adenomas.

Methods

We searched PubMed, EMBASE, and Cochrane Central Register of Controlled Trials from their inception to June 2019 for the identification of trials comparing the EPE with standard patient education for outpatients undergoing colonoscopy. We used a random effects model to calculate summary estimates of the polyp detection rate (defined as the number of patients with at least one polyp divided by the total number of patients undergoing selective colonoscopy), adenoma detection rate (defined as the number of patients with at least one adenoma divided by the total number of patients undergoing selective colonoscopy), advanced adenoma detection rate (defined as the number of patients with at least one advanced adenoma divided by the total number of patients undergoing selective colonoscopy), sessile serrated adenoma detection rate (defined as the number of patients with at least one sessile serrated adenoma divided by the total number of patients undergoing selective colonoscopy), cancer detection rate (defined as the number of patients with at least one cancer divided by the total number of patients undergoing selective colonoscopy), or adenoma detection rate - plus (defined as the number of additional adenomas found after the first adenoma per colonoscopy). Moreover, we conducted trial sequential analysis (TSA) to determine the robustness of summary estimates of all primary outcomes.

Results

We included 10 randomized controlled trials enrolling 4560 participants for analysis. The meta-analysis suggested that EPE was associated with an increased polyp detection rate (9 trials; 3781 participants; risk ratio [RR] 1.19, 95% CI 1.05-1.35; P<.05; I²=42%) and adenoma detection rate (5 trials; 2133 participants; RR 1.37, 95% CI 1.15-1.64; P<.001; I2=0%), which were established by TSA. Pooled result from the inverse-variance model illustrated an increase in the sessile serrated adenoma detection rate (3 trials; 1248 participants; odds ratio 1.76, 95% CI 1.22-2.53; P<.05; I²=0%). One trial suggested an increase in the adenoma detection rate - plus (RR 4.39, 95% CI 2.91-6.61; P<.001). Pooled estimates from 3 (1649 participants) and 2 trials (1375 participants) generated no evidence of statistical difference for the advanced adenoma detection rate and cancer detection rate, respectively.

Conclusions

The current evidence indicates that EPE should be recommended to instruct bowel preparation in patients undergoing colonoscopy because it can increase the polyp detection rate, adenoma detection rate, and sessile serrated adenoma detection rate. However, further trials are warranted to determine the efficacy of EPE for advanced adenoma detection rate, adenoma detection rate - plus, and cancer detection rate because of limited data.

Low-residue diet for colonoscopy in veterans: Risk factors for inadequate bowel preparation and patient satisfaction and compliance

Bowel preparation with low-residue diet (LRD) has resulted in higher patient satisfaction and similar polyp detection rates compared to conventional clear liquid diet. However, there is limited experience with LRD in veterans, in whom conditions associated with poor bowel preparation are more prevalent than the general population. To examine risk factors associated with inadequate bowel preparation, we conducted a chart review of outpatient colonoscopies at the Manhattan VA Medical Center from February 2017 to April 2018. To examine patient satisfaction and compliance, we administered an anonymous questionnaire to patients undergoing outpatient colonoscopy from March to August 2018. Patients assessed by chart review (n = 660) were 92% male with a mean age of 64 years. An adequate Boston Bowel Preparation Scale score ≥2 in each colonic segment was achieved in 94% of procedures. Higher BMI, diabetes, prior inadequate bowel preparation, bowel preparation duration of two days, and opioid use were associated with inadequate bowel preparation on univariable analysis. On multiple logistic regression, only higher BMI remained a predictor, with every one-unit increase associated with a 6% increased odds of poor bowel preparation. Questionnaire responses showed 84% of patients were willing to repeat LRD bowel preparation, 85% found the process easy or acceptable, and 78% reported full adherence to LRD. These findings demonstrate that bowel preparation quality, patient satisfaction, and compliance were all high among veterans using LRD.

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.

Comparison of the effect of 1-day and 2-day low residue diets on the quality of bowel preparation before colonoscopy

BACKGROUND/AIM

Low residue diet (LRD) has a similar quality of bowel preparation with clear liquid diet before colonoscopy, but improved patient tolerance. However, the optimal LRD duration is still controversial. In this study, we have compared the effect of a 1-day LRD and 2-day LRD on the quality of bowel preparation and patient tolerance.

PATIENTS AND METHODS

Our prospective, randomized, single-blind trial, single-blind, trial compared two dietary regimens administered the day before colonoscopy. All patients were administered PEG-ES and simethicone for bowel preparation. The primary outcome measure was bowel preparation quality. The secondary outcome measures were insertion time, withdrawal time, polyp detection rate, patient tolerance, and willingness to use the same diet for bowel preparation again. Bowel preparation quality was evaluated using the Boston bowel preparation scale (BBPS). Patient tolerance was evaluated using a hunger-comfort scale.

RESULTS

There was no significant difference in bowel preparation quality between the 2 groups. The 1-day LRD group had a BBPS score of 6.48 ± 1.59 points, while the 2-day LRD group had a score of 6.42 ± 1.06 points (P > 0.05). The groups reported similar colonoscope insertion times, withdrawal times, polyp detection rates and patient tolerance scores (hunger-comfort scores). The numbers of patients who reported that compliance as easy or very easy were 126 (78.2%) in the 1-day group versus 88 (55.0%) in the 2 day group (P < 0.05) and the numbers who were willing to use the diet again in the future were 154 (95.7%) in the 1-day group versus 131 (81.9%) in the 2 day group (P < 0.05).

CONCLUSION

LRD duration (1 day or 2 days) had no significant effect on bowel preparation quality. Patients in the 1-day LRD group had higher tolerance and satisfaction levels than patients in the 2-day LRD group. However, overall satisfaction was higher with the 1-day LRD group than with the 2-day LRD group.

A 3-day low-fibre diet does not improve colonoscopy preparation results compared to a 1-day diet: A randomized, single-blind, controlled trial

Background

Although a 1-day low-fibre diet before colonoscopy is currently recommended, some endoscopists prescribe a 3-day diet.

Objective

The objective of this study was to compare the influence of a 3-day versus a 1-day low-fibre diet on bowel preparation quality, patient tolerability and adherence.

Methods

Outpatients scheduled for total colonoscopy were randomized in two groups, 3-day versus 1-day low-fibre diet, performing a 4-litre polyethylene glycol split-dose. The primary outcome was a reduction of inappropriate preparations in the 3-day low-fibre diet arm from 15% to 5% (bowel preparation was assessed by the Boston Bowel Preparation Scale). Secondary outcomes were adherence to, difficulty to perform, difficulty to obtain and willingness to repeat the diet. Intention-to-treat (ITT) and per-protocol (PP) analyses were conducted for the primary outcome.

Results

A total of 412 patients were randomized (206 per group). Bowel preparation quality was similar between groups. On ITT analysis (n = 412), adequate bowel preparation was 91.7% (3-day diet) versus 94.7% (1-day diet), p = 0.24 and on PP analysis (n = 400) 93.5% versus 96.5%, respectively, p = 0.16. Difficulty to perform the diet was significantly higher on the 3-day diet, p = 0.04. No differences were found on difficulty to obtain the diet, willingness to repeat the diet, adverse events and intra-colonoscopy findings.

Conclusion

A 3-day low-fibre diet does not bring benefit to the bowel preparation quality and is harder to perform than a 1-day diet.

Strategies to Improve Inadequate Bowel Preparation for Colonoscopy

Bowel cleansing is one of the most important parameters included in the evaluation of colonoscopy quality. The available evidence suggests that inadequate bowel preparation reduces the diagnostic yield of colorectal neoplasia and increases post-colonoscopy colorectal cancer risk. Nowadays, up to 30% of patients referred for colonoscopy have a poor bowel cleansing. Recently, several studies have analyzed the risk factors for inadequate bowel cleansing as well as the strategies to optimize bowel preparation. In this review, we have focused on summarizing the available evidence in this field.

Randomized Controlled Trial: Split-dose and Same-day Large Volume Bowel Preparation for Afternoon Colonoscopy Have Similar Quality of Preparation

GOALS

We compare bowel cleanliness in patients taking same-day versus split-dose 4-L polyethylene glycol laxative for afternoon colonoscopy. Secondary objectives included patient satisfaction, adverse effects and patient tolerability.

BACKGROUND

Afternoon colonoscopies have been associated with inadequate bowel preparation and lower adenoma detection rates. Same-day (morning) or split-dosing of the laxative have improved preparation quality but differences between these options are unclear.

MATERIALS AND METHODS

Single-center prospective randomized endoscopist blinded trial. Patients aged 18 years and above prescribed 4-L polyethylene glycol for colonoscopy were randomized into same-day or split-dose preparation. Preparation quality was assessed using the Ottawa Bowel Preparation Scale. Patient satisfaction and side effects was collected using a questionnaire. Intention-to-treat and per-protocol analysis were performed.

RESULTS

A total of 300 patients (158 split-dose, 142 same-day) were evaluated. No statistically significant difference was seen on total Ottawa score among the groups (P=0.47) or by individual colonic segments in intent-to-treat and per-protocol analysis. Patients in split-dose group were more likely to complete the entire preparation (P=0.01) but reported more sleep loss (P=0.001). The same-day preparation group reported higher incidence of vomiting (P=0.036). Patients ingesting bowel preparation ≥7 hours before colonoscopy had higher total Ottawa scores (P=0.001).

CONCLUSIONS

There were no differences in quality of preparation in patients taking same-day versus split-dose preparation for afternoon colonoscopy. Those receiving same-day preparation were less likely to lose sleep but more likely to have emesis. These differences should be considered when selecting a bowel preparation regimen.

A low-residue diet before colonoscopy tends to improve tolerability by patients with no differences in preparation quality: a randomized trial

BACKGROUND

The pre-colonoscopy diet traditionally involves 24 h of a clear liquid diet (CLD) in combination with a lavage solution; however, this preparation is poorly tolerated.

AIM

To compare the impact on the quality of bowel cleansing and tolerability of a CLD versus a low-residue diet (LRD).

METHODS

We performed a randomized trial. Subjects were randomized to CLD or LRD the day before of elective colonoscopy. All subjects received a 4-L preparation of single-dose PEG beginning 16 h prior to colonoscopy. The Boston bowel preparation scale was used to evaluate bowel cleansing; an adequate-quality preparation was defined as a score ≥ 2 per segment.

RESULTS

A total of 205 subjects were included with a mean age (SD) of 55.6 (12.6) years; 133 (64.9%) of them were female. A total of 105 subjects were randomized to receive CLD and 100 to LRD. No significant differences in bowel preparation quality were observed between groups according to the section of colon: right colon (70% vs. 73%, p = 0.08), transverse colon (82% vs. 79%, p = 0.062), or left colon (80% vs. 78.7%, p = 0.28). There was a tendency toward less-frequent nausea (p = 0.08) and vomiting (p = 0.07) in patients with LRD. No differences between groups regarding ADR (12% vs. 10%) were noted.

CONCLUSIONS

An LRD before colonoscopy resulted in a tendency toward improved tolerability by patients, with no differences in the quality of bowel preparation.

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.

Favorable outcomes of prepackaged low-residue diet on bowel preparation for colonoscopy: Endoscopist-blinded randomized controlled trial

BACKGROUND AND AIM

2 L polyethylene glycol plus an ascorbic acid (PEGA) is known to be as effective. However, 2 L polyethylene glycol-based regimens are often still difficult for patients to tolerate. Therefore, we conducted this study to evaluate the potential of 1 L PEGA with prepackaged low-residue diet (PLD) as an alternative to 2 L PEGA before colonoscopy.

METHODS

The subjects were randomly assigned to either of the two groups. The 2 L PEGA group received 2 L PEGA split regimen. The 1 L PEGA with PLD group received PLD on the day preceding colonoscopy and 1 L PEGA. All endoscopic procedures were performed by one physician who did not know patients allocation. Bowel preparation status were graded using Boston Bowel Preparation Score (BBPS). A questionnaire regarding tolerability and safety was administered. This trial is registered at ClinicalTrials.gov (NCT03329339).

RESULTS

A total of 173 patients completed the study (86 in the 2 L PEGA group and 87 in the 1 L PEGA with PLD group). Bowel preparation was adequate in 88.4% (76/86) of patients in the 2 L PEGA group and 93.1% of patients in the 1 L PEGA with PLD group (81/87, P = 0.28). The patients in the 1 L PEGA with PLD group had higher whole Boston Bowel Preparation Scale score (P = 0.02) and expressed more satisfaction and willingness to repeat the procedure (P < 0.01). There was no significant difference with respect to compliance or safety.

CONCLUSION

1 L PEGA with PLD showed equivalent efficacy, greater satisfaction, and more willingness to repeat compared with 2 L PEGA for bowel preparation.

Strategies to optimise the quality of bowel cleansing

Colonoscopy is the gold standard procedure for detecting neoplastic lesions of the colon and its efficiency is closely linked to the quality of the procedure. Adequate bowel preparation is a crucial factor in achieving the recommended quality indicators, but poor preparation has been reported in up to 30% of outpatients referred for colonoscopy. Consequently, over recent years, a number of studies have developed strategies to optimise bowel cleansing by improving adherence and tolerance to and the efficacy of the bowel preparation. Moreover, the identification of risk factors for inadequate bowel cleansing has led to tailored bowel preparation strategies being designed, with promising results. We aimed to review studies that assessed risk factors for inadequate bowel preparation and strategies to optimise bowel cleansing in patients at high risk of having poor preparation.

Antihyperglycemic therapy during colonoscopy preparation: A review and suggestions for practical recommendations

Patients with diabetes have distinct risks during precolonoscopy bowel preparation, caused by change of diet, change of antihyperglycemic medication regimens and diabetes-related complications and comorbidities. These risks include hypoglycemia, water and electrolyte imbalance, acute renal failure, lactic acidosis, ketoacidosis and low quality of bowel preparation. Here we review the existing literature and present recommendations from a subcommittee of the Israeli National Diabetes Council for primary care physicians and gastroenterologists. The instructions include general suggestions on diet and glucose monitoring and specific recommendations on timing of modification or cessation of each of the antihyperglycemic medication types to ensure patient safety during bowel preparation.

Randomized Clinical Trial: A Normocaloric Low-Fiber Diet the Day Before Colonoscopy Is the Most Effective Approach to Bowel Preparation in Colorectal Cancer Screening Colonoscopy

BACKGROUND

Clinical guidelines recommend either a clear-liquid diet or a low-fiber diet for colonoscopy preparation. Participants in a screening program are usually motivated healthy individuals in which a good tolerability is important to improve adherence to potential surveillance colonoscopies.

OBJECTIVE

Our aim was to assess whether or not a normocaloric low-fiber diet followed the day before a screening colonoscopy compromises the efficacy of bowel cleansing and may improve the tolerability of bowel preparation.

DESIGN

This is a randomized, endoscopist-blinded, noninferiority clinical trial.

SETTINGS

The study was conducted at a tertiary care center.

PATIENTS

A total of 276 consecutive participants of the Barcelona colorectal cancer screening program were included.

INTERVENTION

Participants were randomly assigned to a clear-liquid diet or a normocaloric low-fiber diet the day before the colonoscopy. Both groups received 4 L of polyethylene glycol in a split-dose regimen.

MAIN OUTCOME MEASURES

Primary outcome was the adequate bowel preparation rate measured with the Boston bowel preparation scale. Secondary outcomes included tolerability, fluid-intake perception, hunger, side effects, and acceptability.

RESULTS

Participants in both groups were similar in baseline characteristics. Adequate bowel preparation was achieved in 89.1% vs 95.7% in clear-liquid diet and low-fiber diet groups, showing not only noninferiority, but also superiority (p = 0.04). Low-fiber diet participants reported less fluid-intake perception (p = 0.04) and less hunger (p = 0.006), with no differences in bloating or nausea.

LIMITATIONS

The single-center design of the study could limit the external validity of the results. The present findings may not be comparable to other clinical settings.

CONCLUSION

A normocaloric low-fiber diet the day before a screening colonoscopy achieved better results than a clear-liquid diet in terms of adequate colon preparation. Moreover, it also improved the perception of hunger and excessive fluid intake. Registered at clinicaltrials.gov: NCT02401802. See Video Abstract at http://links.lww.com/DCR/A829.

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.

Evaluation of the combined effect of factors influencing bowel preparation and adenoma detection rates in patients undergoing colonoscopy

Background

Colonoscopy is a commonly used modality for screening and surveillance of colorectal cancer (CRC). Therefore, it is essential to have adequate bowel preparation (prep) for the procedure which depends on type of bowel regimens, diet before colonoscopy and timing of the procedure.

Aims

The purpose of this study is to analyse the effect of multiple factors on adenoma detection rate (ADR) and prep quality of colonoscopy. This is the also the first study determining outcomes based on various combinations of diet, timing of the procedure and bowel prep regimens.

Methods

This is a retrospective single-centre observational study. Data about diet before procedure, bowel prepprep regimen and timing of the procedure was collected for patients coming for screening colonoscopy.

Results

Patients with split prep had higher good prep rates (73.8% vs 56.2%) and higher ADRs (34.2 % vs 29.9%) as compared with non-split prep. The good prep quality (65.8% vs 62.1%) and ADRs (31.9% vs 31.5%) were comparable in patients who received clear liquid diet as compared with low residue diet. The good results of bowel prep were obtained with split prep with either clear liquids or low residue diet irrespective of the timing of procedure. The poor prep was noticed in patients who underwent procedure in afternoon, with a low restrictive diet and non-split bowel regimen.

Conclusions

The current study adds to our knowledge about the combined effect of multiple variables affecting the bowel prep quality and ADR. It is imperative to opt for the best combination required for colonoscopy, as this will influence the effectiveness of colonoscopies regarding timely cancer detection and prevention.

Results of a Community-based, Randomized Study Comparing a Clear Liquid Diet With a Low-residue Diet Using a Magnesium Citrate Preparation for Screening and Surveillance Colonoscopies

BACKGROUND

Current bowel preparations for colonoscopy include a clear liquid diet (CLD) along with consumption of a laxative. This dietary restriction along with large volume bowel preparations are barriers to compliance and willingness among patients in scheduling screening examinations. The aim of our study was to compare the efficacy and tolerability of a low-volume split dose magnesium citrate bowel preparation in patients on a low-residue diet (LRD) with those on a CLD.

METHODS

In this single center, single blinded, randomized controlled trial, patients scheduled for outpatient colonoscopies were assigned to either a CLD or a LRD 1 day before the examination. Both groups received a split dose magnesium citrate preparation. The quality of the preparation was rated using the Boston Bowel Preparation Scale (BBPS). Patient satisfaction and side effects were evaluated using a questionnaire.

RESULTS

We were unable to detect a significant difference in the BBPS scores between the LRD and CLD groups (P=0.581). A significantly higher percentage of patients in the LRD group rated the diet as easy compared with the CLD group (P<0.001). Satisfaction scores were significantly higher in the LRD group, compared with the CLD group (P<0.001). The side effect profiles of both arms were similar.

CONCLUSIONS

There was no significant difference between LRD and CLD in patients using a magnesium citrate bowel preparation for screening and surveillance colonoscopies. Patient satisfaction scores were higher with a LRD compared with a CLD. We believe the LRD should be the recommended diet in patients using a standard bowel preparation for screening and surveillance colonoscopy.

Preparation for colonoscopy: Recommendations by an expert panel in Italy

BACKGROUND

Despite several guidelines on bowel preparation being available, their applicability in Italy is poorly investigated.

AIMS

(1) To create expert-based recommendations for the Italian setting based on available international guidelines on bowel preparation for colonoscopy; (2) to assess consensus across the Italian endoscopy community.

METHODS

The study was conducted in 2 phases: (a) statements formulation, (b) assessment of consensus. For the first phase, 6 topics related to bowel preparation were identified: (1) efficacy/tolerability; (2) timing; (3) assessment of quality of bowel preparation; (4) factors associated with inadequate preparation; (5) patient education and (6) impact of organisational factors. For each topic, statements were produced and voted by a panel of experts. For consensus assessment, the invited participants were asked to rate the statements. The statement achieved a good level of agreement when at least 70% of voters agreed with it.

RESULTS

25 statements were agreed in the first phase. Agreement was not achieved by the endoscopy community for 7 statements, mainly concerning practical aspects (i.e. strategies for management of patients with inadequate preparation, organisational factors).

CONCLUSION

A clinically relevant consensus was achieved on the main topics of bowel preparation, such as the choice of laxative and the time of administration, and it may help to homogenize the colonoscopy practice in Italy. Nevertheless, there are a few country-specific preparation-related issues that need to be addressed.

Bowel Preparations Administered the Morning of Colonoscopy Provide Similar Efficacy to a Split Dose Regimen: A Meta Analysis

BACKGROUND

Comparative efficacy of same-day bowel preparations for colonoscopy remains unclear.

AIMS

A meta-analysis of randomized controlled trials comparing the efficacy of same-day versus split dose bowel preparations for colonoscopy.

METHODS

A systematic search was conducted in MEDLINE, clinicaltrials.gov, Cochrane Registry, EMBASE, SCOPUS, Web of Science and CINAHL. Studies were gathered using keywords: "morning preparation", "morning bowel preparation", "same day bowel preparation", and "colonoscopy." Pooled estimates of bowel preparation quality were analyzed among studies with categorical and continuous outcomes according to relative risk (RR) or mean difference (MD). A random effects model was chosen a priori for all analyses.

RESULTS

A total of 1216 studies were retrieved with 15 trials meeting inclusion criteria. The categorical outcome of high quality bowel preparation for any same-day bowel preparation versus any split preparation was no different with a RR 0.95 [0.90;1.00] (P=0.62). Adenoma detection rate (ADR) was not different between groups, RR 0.97 [0.79;1.20] (P=0.81). Willingness to repeat and tolerability did not differ (RR 1.14 [0.96,1.36] (P=0.14) and RR 1.00 [0.96;1.04] (P=0.98), respectively. Adverse events were similar except for bloating, which was less frequent among the same-day preparation group, RR 0.68 [0.40;0.94] (P=0.02).

CONCLUSION

No clinically significant differences were noted among recipients of same day or split dose regimens. Adenoma detection rate, willingness to repeat and tolerability were similar, but bloating and interference with sleep favored the same-day preparations. Given lack of clinical differences, patient preference should dictate timing of colonoscopy preparation.

Impact of diet restriction on bowel preparation for colonoscopy

Diet restriction is one of the difficult parts of bowel preparation for colonoscopy, and many patients do not follow instructions properly. Few studies have evaluated the impact of dietary restriction in real clinical setting. The aim of this study was to study the effect of diet control on bowel preparation with detailed investigation of unacceptable food list in order to reveal what kind of foods are most problematic in clinical practice.Prospective observational study was carried out at a university-affiliated hospital. Around 4 L polyethylene glycol solution was used for bowel preparation on the day of colonoscopy. Patients were allowed to have regular diet until lunch the day before colonoscopy and educated to control diet from 3 days before colonoscopy with information regarding an unacceptable foods list. Factors associated with inadequate bowel preparation were analyzed using univariate statistics and multivariate logistic regression analysis.Of the 245 patients included in the study, 68 patients (27.8%) followed the diet instructions. Fiber-rich vegetables were the most commonly taken unacceptable foods (N = 143, 58.4%). Inadequate bowel preparation (fair and poor by Aronchick scale) was 47.3%. In multivariate analysis, diabetes [odds ratio (OR) 2.878, 95% confidence interval (CI) 1.242-6.671], preparation to colonoscopy interval (OR 1.003, 95% CI 1.000-1.005) and consumption of foods disturbing bowel preparation (OR 2.142, 95% CI 1.108-4.140) were independent predictors of inadequate bowel preparation.We could identify substantially low compliance to diet instructions in real clinical practice. Consumption of any foods disturbing bowel preparation was significant factor predicting inadequate bowel preparation, even though we could not select specific food list compromising preparation significantly. Favorable bowel preparation was achieved in the subgroup compliant to diet restriction, suggesting that regular diet avoiding specific kinds of foods can be possible option for diet restriction before colonoscopy.

Research progress on patient comfort during bowel preparation

Bowel preparation is one of the key and necessary steps for preoperative preparations of multiple operations such as electronic colonoscopy, capsule endoscopy, barium X-ray, colorectal surgery, gynecology surgery, and urology surgery. Although better methods for bowel preparation have been explored continuously, patient intolerance still exists during the current bowel preparation process. Adverse reactions such as nausea and vomiting often occur, leading to poor comfort experience and affecting the patient's compliance and bowel preparation results. This article reviews the factors influencing patient comfort during bowel preparation and the corresponding interventions.