Judgement of the quality of bowel preparation at screening flexible sigmoidoscopy is associated with variability in adenoma detection rates

Impact of Bowel Preparation Quality on Colonoscopy Findings and Colorectal Cancer Deaths in a Nation-Wide Colorectal Cancer Screening Program

INTRODUCTION

Adequate bowel preparation is paramount for a high-quality screening colonoscopy. Despite the importance of adequate bowel preparation, there is a lack of large studies that associated the degree of bowel preparation with long-term colorectal cancer outcomes in screening patients.

METHODS

In a large population-based screening program database in Austria, quality of bowel preparation was estimated according to the Aronchick Scale by the endoscopist (excellent, good, fair, poor, and inadequate bowel preparation). We used logistic regression to assess the influence of bowel preparation on the detection of different polyp types and the interphysician variation in bowel preparation scoring. Time-to-event analyses were performed to investigate the association of bowel preparation with postcolonoscopy colorectal cancer (PCCRC) death.

RESULTS

A total of 335,466 colonoscopies between January 2012 and follow-up until December 2022 were eligible for the analyses. As compared with excellent bowel preparation, adenoma detection was not significantly lower for good bowel preparation (odds ratio 1.01, 95% confidence interval [CI] 0.9971-1.0329, P = 0.1023); however, adenoma detection was significantly lower in fair bowel preparation (odds ratio 0.97, 95% CI 0.9408-0.9939, P = 0.0166). Individuals who had fair or lower bowel preparation at screening colonoscopy had significantly higher hazards for PCCRC death (hazard ratio for fair bowel preparation 2.56, 95% CI 1.67-3.94, P < 0.001).

DISCUSSION

Fair bowel preparation on the Aronchick Scale was not only associated with a lower adenoma detection probability but also with increased risk of PCCRC death. Efforts should be made to increase bowel cleansing above fair scores.

Impact of inadequate bowel cleansing in sigmoidoscopy screening

BACKGROUND AND STUDY AIMS

Long-time follow-up of sigmoidoscopy screening trials has shown reduced incidence and mortality of colorectal cancer (CRC), but inadequate bowel cleansing may hamper efficacy. The aim of this study was to assess the impact of bowel cleansing quality in sigmoidoscopy screening.

PATIENTS AND METHODS

Individuals 50 to 74 years old who had a screening sigmoidoscopy in a population-based Norwegian, randomized trial between 2012 and 2019, were included in this cross-sectional study. The bowel cleansing quality was categorised as excellent, good, partly poor, or poor. The effect of bowel cleansing quality on adenoma detection rate (ADR) and referral to colonoscopy was evaluated by fitting multivariable logistic regression models.

RESULTS

35,710 individuals were included. The bowel cleansing at sigmoidoscopy was excellent in 20,934 (58.6%) individuals, good in 6580 (18.4%), partly poor in 7097 (19.9%) and poor in 1099 (3.1%). The corresponding ADRs were 17.0%, 16.6%, 14.5%, and 13.0%. Compared to participants with excellent bowel cleansing, those with poor bowel cleansing had an odds ratio for adenoma detection of 0.66 (95% confidence interval 0.55-0.79). We found substantial differences in the assessment of bowel cleansing quality among endoscopists.

CONCLUSIONS

Inadequate bowel cleansing reduces the efficacy of sigmoidoscopy screening, by lowering ADR. A validated rating scale and improved bowel preparation are needed to make sigmoidoscopy an appropriate screening method.

Trial registration Clinicaltrials.gov (NCT01538550).

The impact of endoscopist performance and patient factors on distal adenoma detection and colorectal cancer incidence

BACKGROUND

High quality endoscopy is key for detecting and removing precursor lesions to colorectal cancer (CRC). Adenoma detection rates (ADRs) measure endoscopist performance. Improving other components of examinations could increase adenoma detection.

AIMS

To investigate how endoscopist performance at flexible sigmoidoscopy (FS) affects adenoma detection and CRC incidence.

METHODS

Among 34,139 participants receiving FS screening by the main endoscopist at one of 13 centres in the UK FS Screening Trial, median follow-up was 17 years. Factors examined included family history of CRC, bowel preparation quality, insertion and withdrawal time, bowel segment reached, patient pain and ADR. Odds ratios (OR) for distal adenoma detection were estimated by logistic regression. Hazard ratios (HR) for distal CRC incidence were estimated by Cox regression.

RESULTS

At screening, 4,104 participants had distal adenomas detected and 168 participants developed distal CRC during follow-up. In multivariable models, a family history of CRC (yes vs. no: OR 1.40, 95%CI 1.21-1.62), good or adequate bowel preparation quality (vs. excellent: OR 0.84, 95%CI 0.74-0.95; OR 0.56, 95%CI 0.49-0.65, respectively) and longer insertion and withdrawal times (≥ 4.00 vs. < 2.00 min: OR 1.96, 95%CI 1.68-2.29; OR 32.79, 95%CI 28.22-38.11, respectively) were associated with adenoma detection. Being screened by endoscopists with low or intermediate ADRs, compared to high ADRs, was positively associated with CRC incidence (multivariable: HR 4.71, 95%CI 2.65-8.38; HR 2.16, 95%CI 1.22-3.81, respectively).

CONCLUSIONS

Bowel preparation quality and longer insertion and withdrawal time are key for improving distal adenoma detection. Higher ADRs were associated with a lower risk of distal CRC.

AN ELECTRONIC MEDICAL RECORD PREDICTION MODEL TO IDENTIFY INADEQUATE BOWEL PREPARATION IN PATIENTS AT OUTPATIENT COLONOSCOPY

Background and Aims

Inadequate bowel preparation during colonoscopy is associated with decreased adenoma detection, increased costs, and patient procedural risks. This study aimed to develop a prediction model for identifying patients at high risk of inadequate bowel preparation for potential clinical integration into the EMR.

Methods

A retrospective study was conducted using outpatient screening/surveillance colonoscopies at the University of North Carolina (UNC) from 2017 to 2022. Data were extracted from the EMRs of Epic and ProVation, including demographic, socioeconomic, and clinical variables. Logistic regression, LASSO regression, and gradient boosting machine (GBM) models were evaluated and validated in a held-out testing set.

Results

The dataset included 23,456 colonoscopies, of which 6.25% had inadequate bowel preparation. The reduced LASSO regression model demonstrated an area under the curve (AUC) of 0.65 [95% CI 0.63-0.67] in the held-out testing set. The relative risk of inadequate bowel prep in the high-risk group determined by the model was 2.42 (95% CI 2.07-2.82), compared to patients identified as low risk. The model calibration in the testing set revealed that among patients categorized as having 0-11%, 11-22%, and 22-33% predicted risk of inadequate prep, the respective proportions of patients with inadequate prep were 5.5%, 19.3%, and 33.3%. Using the reduced LASSO model, a rudimentary code for a potential Epic FHIR application called PrepPredict was developed.

Conclusions

This study developed a prediction model for inadequate bowel preparation with the potential to integrate into the EMR for clinical use and optimize bowel preparation to improve patient care.

Colorectal Cancer in Inflammatory Bowel Diseases: Epidemiology and Prevention: A Review

Simple Summary

Colorectal cancer (CRC) is one of the most serious potential complications of inflammatory bowel diseases (IBDs). The aging of patients affected by IBDs makes this issue a challenge that will increasingly be faced by clinicians in clinical practice, especially in light of the poorer prognosis for CRC in this group of people when compared with the general population. In this review, we summarize the current epidemiology, risk factors and various prevention strategies proposed for CRC in patients with IBDs.

Abstract

Colorectal cancer (CRC) is currently the third most frequent form of malignancy and the second in terms of mortality. Inflammatory bowel diseases (IBDs) are recognized risk factors for this type of cancer. Despite a worldwide increase in the incidence of CRC, the risk of CRC-related death in IBD patients has declined over time, probably because of successful surveillance strategies, the use of more effective drugs in the management of remission and improved indications to colectomy. This notwithstanding, CRC 5-year survival in patients with IBD is poorer than in the general population. This review provides a summary of the epidemiological features, risk factors and various prevention strategies proposed for CRC in IBD patients. Moreover, there is a special focus on reporting and highlighting the various prevention strategies proposed by the most important international scientific societies, both in terms of chemoprevention and endoscopic surveillance. Indeed, in conducting the analysis, we have given attention to the current primary, secondary and tertiary prevention guidelines, attempting to emphasize unresolved research and clinical problems related to this topic in order to improve diagnostic strategies and management.

The necessity of intensive surveillance colonoscopy for patients with a remaining right colon after resection of colorectal cancer: a retrospective cohort study

PURPOSE

To clarify how often postoperative surveillance colonoscopy should be undertaken based on the risk factors for the development of metachronous cancer (MC) and advanced adenoma (AA) after surgery for colorectal cancer.

METHODS

We collected data of consecutive patients who underwent curative resection for primary colorectal cancer between 2005 and 2012, with preoperative colonoscopy and surveillance colonoscopy at 1 year after surgery (406 patients, mean age: 69 years, 59% male). The detection rates of AA (with villous features, > 10 mm or high-grade dysplasia) and MC by surveillance colonoscopy were the primary outcomes.

RESULTS

At 5 years, colonoscopy was performed as postoperative surveillance an average of 3.2 times. AA and MC were detected in 57 (14.0%) and 18 patients (4.4%), respectively. Both lesions were more common in the right colon (n = 43) than in the left colon (n = 28). The detection rate did not differ to a statistically significant extent according to the number of colonoscopies performed for surveillance (p = 0.21). However, after left-sided colectomy, both types of lesions were more commonly detected in those who received ≥ 3 colonoscopies than in those with one or two colonoscopies (p = 0.04).

CONCLUSION

A remaining right colon after left-sided colectomy was associated with a higher risk of developing AA and MC. Physicians should consider performing surveillance colonoscopy more frequently if the right colon remains after surgery.

Quality of Preoperative Colonoscopy Affects Missed Postoperative Adenoma Detection in Colorectal Cancer Patients

BACKGROUND

Despite thorough preoperative screening, 19-30% of synchronous polyps or adenomas are detected after colon cancer surgery. Remnant synchronous lesions require additional colonoscopy procedures or surgery.

AIM

To investigate factors of preoperative colonoscopy potentially affecting the detection of missed lesions in patients subjected to colorectal cancer surgery.

METHODS

Of 1147 colorectal cancer patients subjected to curative open or laparoscopic colectomy and colonoscopy at the Chungnam National University Hospital from January 2012 to December 2016, 518 patients underwent pre- and postoperative colonoscopy. The index colonoscopy was defined as the last preoperative endoscopy performed. We analyzed pre- and postoperative medical charts for colonoscopy and pathological data. The effects of patient, procedure, and tumor factors on the postoperative adenoma detection rate, advanced adenoma detection rate, and adenoma miss rate (AMR) were analyzed.

RESULTS

The overall AMR was 25.7% (95% confidence interval, 22.2-29.8%). Comparing optimal and non-optimal bowel preparation groups, the latter had greater postoperative polyp missed rate (PMR), AMR (p < 0.01), and AAMR (p = 0.272). The optimal preparation group allowed identification of more synchronous adenomas than in the fair (OR 5.72) and poor (OR 11.39) preparation groups. On univariate analysis, patient age and left-sided colectomy (p < 0.01) influenced AMR. Multivariate analysis showed that age, preoperative bowel preparation, and left colon resection influenced postoperative AMR.

CONCLUSION

A better quality of index colonoscopy had a positive effect on lowering the detection rate of postoperative adenoma. Older age and suboptimal bowel preparation at the index colonoscopy and left-sided colectomy had negative effects on lowering the postoperative AMR.

Factors affecting adenoma detection rate in a national flexible sigmoidoscopy screening programme: a retrospective analysis

BACKGROUND

A national colorectal cancer screening programme started in England in 2013, offering one-off flexible sigmoidoscopy to all men and women aged 55 years in addition to the biennial faecal occult blood testing programme offered to all individuals aged 60-74 years. We analysed data from six pilot flexible sigmoidoscopy screening centres to examine factors affecting the adenoma detection rate (ADR).

METHODS

We did a retrospective analysis of flexible sigmoidoscopy screening procedures performed in individuals aged 55 years at six pilot sites in England as part of the National Health Service Bowel Scope Screening programme. ADR (number of procedures in which at least one adenoma was removed or biopsied, divided by total number of procedures) was calculated for each site and each endoscopist. Multiple regression models were used to examine the variation in ADR with withdrawal time and extent of examination, and the effect of other factors including comfort and bowel preparation on extent of examination.

FINDINGS

The analysis included 8256 procedures done between May 7, 2013, and May 6, 2014. The overall ADR was 9·1% (95% CI 8·5-9·8; 755 of 8256 procedures), varying from 7·4% (6·2-8·9) to 11·0% (9·1-13·4) by screening centre. The ADR was 11·5% (95% CI 10·6-12·5; 493 of 4299 procedures) in men and 6·6% (5·9-7·4; 262 of 3957 procedures) in women (p<0·0001). On multivariate analysis, factors associated with adenoma detection were male sex (relative risk 1·69, 95% CI 1·46-1·95; p<0·0001) and a withdrawal time from the splenic flexure of at least 3·25 min in negative procedures (1·22, 1·00-1·48; p=0·045). However, increasing the withdrawal time to 4·0 min or more did not increase the likelihood of adenoma detection (1·22, 0·99-1·51; p=0·057). Procedures not reaching the splenic flexure were associated with lower chance of adenoma detection (eg, 0·77, 0·66-0·91; p=0·0015 for procedures reaching the descending colon), but there was no additional benefit associated with reaching the transverse colon (0·83, 0·67-1·02; p=0·069). Women (0·83, 0·80-0·87; p<0·0001), individuals with adequate (0·79, 0·76-0·83; p<0·0001) or poor (0·58, 0·51-0·67; p<0·0001) bowel preparation (compared with good bowel preparation), and those with mild (0·82, 0·76-0·88; p<0·0001) or moderate or severe (0·58, 0·51-0·66; p<0·0001) discomfort (compared with no discomfort) were less likely to have a procedure reaching the splenic flexure.

INTERPRETATION

Key performance indicators for flexible sigmoidoscopy screening should be defined, including standards for insertion and withdrawal times, optimal depth, and bowel preparation. ADR could be improved by recommending a withdrawal time from the splenic flexure of at least 3·25 min (ideally 3·5-4·0 min).

FUNDING

None.

Educational Video Followed by Retelling Bowel Preparation Process to Improve Colonoscopy Bowel Preparation Quality: A Prospective Nursing Intervention Study

Background

This study investigated the effect of a patient education video followed by retelling the process of bowel preparation on colonoscopy bowel preparation quality.

Material/Methods

This was a prospective, randomized, controlled clinical trial of outpatients undergoing colonoscopy. Patients were randomized (1: 1) to the video + retelling group or the control group. The primary endpoint was to assess the bowel preparation quality using the Ottawa Bowel Preparation Quality scale (Ottawa score). Risk factors associated with poor bowel preparation were also evaluated.

Result

The video + retelling group had a higher percentage of patients with adequate colonoscopy bowel preparation (Ottawa score <6) than the control group (P<0.001). Mean Ottawa total scores significantly differed between the control group and the video + retelling group (4.18±1.4 vs. 3.05±1.3, P<0.001). The video + retelling group showed superior cleanliness in the right, middle, and recto-sigmoid colon segments (all Ps <0.001). Logistic regression analysis revealed that male gender (OR=2.10, 95%CI: 1.098–4.018, P=0.025), diabetes mellitus (OR=2.830, 95%CI: 1.257–6.372, P=0.012), and no educational video followed by retelling bowel preparation process (OR=3.02, 95%CI: 1.731–5.270, P<0.001) were independently associated with poor bowel preparation.

Conclusions

Use of an educational video followed by asking patients to retell the process of bowel preparation after receiving regular instructions is a convenient and risk-free practice that enhances the compliance with bowel preparation guidance and improves bowel preparation quality.

Impact of Colonoscopy Bowel Preparation Quality on Follow-up Interval Recommendations for Average-risk Patients With Normal Screening Colonoscopies: Data From the New Hampshire Colonoscopy Registry

BACKGROUND AND AIMS

National guidelines for colonoscopy screening and surveillance assume adequate bowel preparation. We used New Hampshire Colonoscopy Registry (NHCR) data to investigate the influence of bowel preparation quality on endoscopist recommendations for follow-up intervals in average-risk patients following normal screening colonoscopies.

METHODS

The analysis included 9170 normal screening colonoscopies performed on average risk individuals aged 50 and above between February 2005 and September 2013. The NHCR Procedure Form instructs endoscopists to score based on the worst prepped segment after clearing all colon segments, using the following categories: excellent (essentially 100% visualization), good (very unlikely to impair visualization), fair (possibly impairing visualization), and poor (definitely impairing visualization). We categorized examinations into 3 preparation groups: optimal (excellent/good) (n=8453), fair (n=598), and poor (n=119). Recommendations other than 10 years for examinations with optimal preparation, and >1 year for examinations with poor preparation, were considered nonadherent.

RESULTS

Of all examinations, 6.2% overall received nonadherent recommendations, including 5% of examinations with optimal preparation and 89.9% of examinations with poor preparation. Of normal examinations with fair preparation, 20.7% of recommendations were for an interval <10 years. Among those examinations with fair preparation, shorter-interval recommendations were associated with female sex, former/nonsmokers, and endoscopists with adenoma detection rate ≥20%.

CONCLUSIONS

In 8453 colonoscopies with optimal preparations, most recommendations (95%) were guideline-adherent. No guideline recommendation currently exists for fair preparation, but in this investigation into community practice, the majority of the fair preparation group received 10-year follow-up recommendations. A strikingly high proportion of examinations with poor preparation received a follow-up recommendation greater than the 1-year guideline recommendation. Provider education is needed to ensure that patients with poor bowel preparation are followed appropriately to reduce the risk of missing important lesions.

Clinical Practice Impact of the Boston Bowel Preparation Scale in a European Country

Introduction

The diagnostic acuity of colonoscopy requires a careful evaluation of the colonic mucosa, so an adequate bowel cleansing is a key element of the procedure. It is internationally recommended that an evaluation of the quality of the intestinal preparation should be included in the colonoscopy report. The Boston Bowel Preparation Scale (BBPS) is a bowel cleanliness rating scale that has gained some preponderance in this context. However, its application implies some degree of subjective appreciation, and it is important to conduct interobserver reproducibility studies in different contexts. The objective of the present study was to evaluate the reliability of the BBPS in the Portuguese gastroenterological community.

Methods

A prospective study involving Portuguese gastroenterologists with clinical practice in several contexts, and using different methods of evaluation of the intestinal preparation. Participants were invited to answer a questionnaire encompassing 93 static images and 12 video segments of colonoscopy examinations, with different levels of intestinal preparation. For each item, the participant gastroenterologist assigned a score of 0-3, according to the BBPS criteria. A statistical analysis was performed with SPSS 20.0 software, using the intraclass correlation coefficient (ICC).

Results

From 45 invited gastroenterologists, 36 replied (mean age 39 ± 9 years). Fifteen (41%) had more than 10 years of colonoscopy experience and 20 (56%) performed more than 40 examinations per month. Twenty-seven (77%) usually used the BBPS in their daily practice. Statistical analysis revealed a strong interobserver correlation (ICC = 0.783) in the application of the BBPS, even in those gastroenterologists who did not use the scale in their daily routine (ICC = 0.775) and those with less years of experience (ICC = 0.820). The correlation in the videos was slightly lower than that observed in the static images (ICC = 0.74 vs. ICC = 0.78).

Conclusion

The application of the BBPS in the Portuguese gastroenterology community is reproducible and can represent a way to harmonize the colonoscopy reports, contributing to its correct interpretation and subsequent patient orientation.

The clinical effectiveness of different surveillance strategies to prevent colorectal cancer in people with intermediate-grade colorectal adenomas: a retrospective cohort analysis, and psychological and economic evaluations

BACKGROUND

The UK guideline recommends 3-yearly surveillance for patients with intermediate-risk (IR) adenomas. No study has examined whether or not this group has heterogeneity in surveillance needs.

OBJECTIVES

To examine the effect of surveillance on colorectal cancer (CRC) incidence; assess heterogeneity in risk; and identify the optimum frequency of surveillance, the psychological impact of surveillance, and the cost-effectiveness of alternative follow-up strategies.

DESIGN

Retrospective multicentre cohort study.

SETTING

Routine endoscopy and pathology data from 17 UK hospitals (n = 11,944), and a screening data set comprising three pooled cohorts (n = 2352), followed up using cancer registries.

SUBJECTS

Patients with IR adenoma(s) (three or four small adenomas or one or two large adenomas).

PRIMARY OUTCOMES

Advanced adenoma (AA) and CRC detected at follow-up visits, and CRC incidence after baseline and first follow-up.

METHODS

The effects of surveillance on long-term CRC incidence and of interval length on findings at follow-up were examined using proportional hazards and logistic regression, adjusting for patient, procedural and polyp characteristics. Lower-intermediate-risk (LIR) subgroups and higher-intermediate-risk (HIR) subgroups were defined, based on predictors of CRC risk. A model-based cost-utility analysis compared 13 surveillance strategies. Between-group analyses of variance were used to test for differences in bowel cancer worry between screening outcome groups (n = 35,700). A limitation of using routine hospital data is the potential for missed examinations and underestimation of the effect of interval and surveillance.

RESULTS

In the hospital data set, 168 CRCs occurred during 81,442 person-years (pys) of follow-up [206 per 100,000 pys, 95% confidence interval (CI) 177 to 240 pys]. One surveillance significantly lowered CRC incidence, both overall [hazard ratio (HR) 0.51, 95% CI 0.34 to 0.77] and in the HIR subgroup (n = 9265; HR 0.50, 95% CI 0.34 to 0.76). In the LIR subgroup (n = 2679) the benefit of surveillance was less clear (HR 0.62, 95% CI 0.16 to 2.43). Additional surveillance lowered CRC risk in the HIR subgroup by a further 15% (HR 0.36, 95% CI 0.20 to 0.62). The odds of detecting AA and CRC at first follow-up (FUV1) increased by 18% [odds ratio (OR) 1.18, 95% CI 1.12 to 1.24] and 32% (OR 1.32, 95% CI 1.20 to 1.46) per year increase in interval, respectively, and the odds of advanced neoplasia at second follow-up increased by 22% (OR 1.22, 95% CI 1.09 to 1.36), after adjustment. Detection rates of AA and CRC remained below 10% and 1%, respectively, with intervals to 3 years. In the screening data set, 32 CRCs occurred during 25,745 pys of follow-up (124 per 100,000 pys, 95% CI 88 to 176 pys). One follow-up conferred a significant 73% reduction in CRC incidence (HR 0.27, 95% CI 0.10 to 0.71). Owing to the small number of end points in this data set, no other outcome was significant. Although post-screening bowel cancer worry was higher in people who were offered surveillance, worry was due to polyp detection rather than surveillance. The economic evaluation, using data from the hospital data set, suggested that 3-yearly colonoscopic surveillance without an age cut-off would produce the greatest health gain.

CONCLUSIONS

A single surveillance benefited all IR patients by lowering their CRC risk. We identified a higher-risk subgroup that benefited from further surveillance, and a lower-risk subgroup that may require only one follow-up. A surveillance interval of 3 years seems suitable for most IR patients. These findings should be validated in other studies to confirm whether or not one surveillance visit provides adequate protection for the lower-risk subgroup of intermediate-risk patients.

STUDY REGISTRATION

Current Controlled Trials ISRCTN15213649.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

A randomized controlled trial of an educational video to improve quality of bowel preparation for colonoscopy

BACKGROUND

High-quality bowel preparation is necessary for colonoscopy. A few studies have been conducted to investigate improvement in bowel preparation quality through patient education. However, the effect of patient education on bowel preparation has not been well studied.

METHODS

A randomized and prospective study was conducted. All patients received regular instruction for bowel preparation during a pre-colonoscopy visit. Those scheduled for colonoscopy were randomly assigned to view an educational video instruction (video group) on the day before the colonoscopy, or to a non-video (control) group. Qualities of bowel preparation using the Ottawa Bowel Preparation Quality scale (Ottawa score) were compared between the video and non-video groups. In addition, factors associated with poor bowel preparation were investigated.

RESULT

A total of 502 patients were randomized, 250 to the video group and 252 to the non-video group. The video group exhibited better bowel preparation (mean Ottawa total score: 3.03 ± 1.9) than the non-video group (4.21 ± 1.9; P < 0.001) and had good bowel preparation for colonoscopy (total Ottawa score <6: 91.6 % vs. 78.5 %; P < 0.001). Multivariate analysis revealed that males (odds ratio [OR] = 1.95, P = 0.029), diabetes mellitus patients (OR = 2.79, P = 0.021), and non-use of visual aids (OR = 3.09, P < 0.001) were associated with poor bowel preparation. In the comparison of the colonoscopic outcomes between groups, the polyp detection rate was not significantly different between video group and non-video group (48/250, 19.2 % vs. 48/252, 19.0 %; P = 0.963), but insertion time was significantly short in video group (5.5 ± 3.2 min) than non-video group (6.1 ± 3.7 min; P = 0.043).

CONCLUSION

The addition of an educational video could improve the quality of bowel preparation in comparison with standard preparation method.

TRIAL REGISTRATION

Clinical Research Information Service KCT0001836 . The date of registration: March, 08(th), 2016, Retrospectively registered.

Clinical trial: free fatty acid suppositories compared with enema as bowel preparation for flexible sigmoidoscopy

OBJECTIVES

The purpose of this trial was to evaluate the efficacy and safety of recently developed suppositories containing free fatty acids as a bowel-cleansing agent prior to flexible sigmoidoscopy and compare them with Klyx (docusate sodium/sorbitol).

DESIGN

A controlled, non-inferiority, single-blind, randomised study on outpatients undergoing flexible sigmoidoscopy.

SETTING

Department of Gastroenterology, Landspitali-University Hospital and endoscopic clinic.

PATIENTS

53 outpatients undergoing flexible sigmoidoscopy.

INTERVENTION

Participants were randomised to receive either free fatty acid suppositories (28) or a standard bowel preparation with Klyx enema (25). In the study group, two suppositories were administered the evening before as well as 2 h prior to the sigmoidoscopy. In the control group, Klyx enema (120 mL) was administered the evening before and repeated 2 h prior to the procedure.

MAIN OUTCOME MEASUREMENTS

Quality of the bowel cleansing, height of scope insertion and safety.

RESULTS

The mean height of scope insertion and bowel cleansing was 43 cm (SD=13.4) in the study group and 48 cm (SD=10.4) in the control group (NS). The investigating physicians were less satisfied with the bowel preparation in the study group compared with the control group with a difference of 20% (p<0.016). The amount of faeces noted in the rectum was similar in both groups with no significant difference (p<0.56). No serious side effects, toxic reaction or irritation were observed.

CONCLUSIONS

The suppositories are well tolerated with no significant side effects. The suppositories had distinct bowel emptying effect and as effective as Klyx in rectal cleansing. Although physician's satisfaction was slightly lower, the height of scope insertion was similar.

TRIAL REGISTRATION NUMBER

EudraCT nr.: 2010-018761-35.

Rates of Suboptimal Preparation for Colonoscopy Differ Markedly Between Providers: Impact on Adenoma Detection Rates

GOALS

We sought to determine if providers who have higher standards for optimal bowel preparation might be more fastidious in their examination of the colon and, therefore, have higher adenoma detection rates (ADRs).

BACKGROUND

ADRs are a reliable and objective marker of colonoscopy performance. Suboptimal bowel preparation impacts upon adenoma detection; however, physicians have varying standards for grading bowel preparation.

STUDY

Endoscopy reports of patients who underwent screening colonoscopy in 2011 at 1 academic medical center were reviewed. Bowel preparations labeled "fair," "poor," or "unsatisfactory" were considered suboptimal. The ADR was calculated for each endoscopy provider and was correlated with the provider's suboptimal preparation rate. Logistic regression was used to determine independent predictors of adenoma detection.

RESULTS

1649 examinations from 11 separate gastroenterologists were included. Preparation was suboptimal in 22% of examinations overall. The rate of suboptimal preparations varied widely among providers, ranging from 3% to 40%. Overall ADR was 23%, with a range of 13% to 31%. Providers' suboptimal preparation rate was not significantly correlated with ADR (r=-0.22, P=0.51). After adjusting for age and sex, adenoma detection was not associated with provider suboptimal preparation rate (P=0.28).

CONCLUSIONS

Rates of suboptimal preparation vary widely between providers, but were not correlated with ADR. This suggests that a high suboptimal preparation rate is not a marker of higher quality standards and expectations by the provider. The impact of physician personality traits on colonoscopy performance requires further study.

Gastrointestinal cancer screening: screening may release new research funding to improve health service also in routine clinics

We are far from having seen the ideal method of screening for colorectal cancer (CRC) and the downsides of screening have not been fully addressed. Funding of adequately sized screening trials with a 10-15-year perspective for endpoints CRC mortality and incidence is difficult to get. Also, with such time horizons, there will always be an ongoing study to be awaited before feeling obliged to invest in the next. New, promising screening methods may, however, emerge far more often than every 10th year, and the knowledge gap may easily widen unless research is made a key responsibility for any ongoing cancer screening program. Previous lost battles on screening research may be won if accepting that scientific evidence may be obtained within the framework of screening programs - provided that they are designed as platforms for Comparative Effectiveness Research (CER). Accepting that CER-based screening programs should be preferred to non-CER programs and seriously compete for their funding sources, then CER screening programs may not be considered so much as contenders for ordinary clinical research funds. Also, CER within a screening framework may benefit patients in routine clinics as shown by screening research in Nordic countries. The Nordic countries have been early contributors to research on CRC screening, but slow in implementing screening programs.

Adenoma detection in excellent versus good bowel preparation for colonoscopy

GOAL

To determine whether Excellent bowel cleansing is superior to Good for the detection of adenomas.

BACKGROUND

High quality colonoscopy requires Adequate bowel preparation. However, it is unknown whether adenoma detection differs between subcategories of Adequate cleansing.

STUDY

We utilized a retrospective, cross-sectional study design to obtain data about patients undergoing colonoscopy at a single university center between August 31, 2011 and September 1, 2012. Primary outcome was adenoma detection rate (ADR), the percentage of patients with ≥1 adenoma. Secondary outcomes included adenomas per colonoscopy, adenoma distribution (proximal vs. distal), and detection of advanced adenomas, sessile serrated polyps (SSP), and cancer.

RESULTS

The electronic medical record of 5113 consecutive colonoscopies with Good or Excellent preparation was queried for preparation quality, colonoscopy indication, demographics, medical history, and history of adenoma and colon cancer. Exclusion criteria were age below 18 years, inflammatory bowel disease, or familial polyposis. Adenoma detection was not superior with Excellent cleansing as compared with Good for ADR [respectively, 26% vs. 29%, odds ratio 0.97 (0.85, 1.11), P=0.618] or adenomas per colonoscopy [respectively, 0.437 vs. 0.499, incidence rate ratio (IRR) 0.98 (0.90, 1.07), P=0.705]. Excellent cleansing demonstrated superior detection of SSPs [IRR 1.66 (1.14, 2.40), P=0.008] and advanced adenomas [IRR 1.37 (1.09, 1.72), P=0.007] but not colon cancer [odds ratio 0.286 (0.083, 0.985), P=0.0474].

CONCLUSIONS

ADR is not significantly different between the Adequate subcategories of Excellent and Good. However, Excellent cleansing is associated with superior detection of advanced adenomas and SSPs. If confirmed, achieving an Excellent preparation may improve colonoscopy performance in the proximal colon where SSPs primarily occur.

Assessing bowel preparation quality using the mean number of adenomas per colonoscopy

INTRODUCTION

The quality of the bowel preparation directly influences colonoscopy effectiveness. Quality indicators are widely employed to monitor operator performance and to gauge colonoscopy effectiveness. Some have suggested that the enumeration of the mean number of adenomas per colonoscopy (MNA) may be a more useful measure of bowel preparation quality, but evidence of the utility of this metric is limited. The relationship between bowel preparation quality and MNA was assessed.

METHODS

Records of adult patients, aged 50-74 years, who had undergone a screening colonoscopy in a 6 month period at a hospital-based endoscopy suite in New York City were examined. Excluded were those who were symptomatic or having a colonoscopy for surveillance. Patient and procedural characteristics and clinical findings were abstracted from the endoscopy database. Bowel preparation quality was recorded as excellent, good, fair and poor. Histology and size of polyps removed were gathered from pathology reports. MNA was calculated and incident rate ratios assessing the relationship between bowel preparation quality, MNA, and covariates was calculated using Poisson regression.

RESULTS

A total of 2422 colonoscopies were identified; 815 (33.6%) were screening colonoscopies among average risk individuals, 50-74 years; 203 (24.9%) had ≥1 adenomas; and 666 (81.7%) had excellent/good preparation quality. Overall MNA was 0.34 [standard deviation (SD) 0.68] and MNA was greater among those >60 years [incident rate ratio (IRR) 1.89, 95% confidence interval (CI) 1.48-2.42), males (IRR 1.60, 95%CI 1.26-2.04) and those with good bowel preparation (IRR 2.54, 95%CI 1.04-6.16). Among those with ≥1 adenomas, MNA was 1.48 (SD 1.05) for excellent and 1.00 (SD 0.00) for poor quality preparation (p = 0.55).

CONCLUSIONS

We found that MNA is sensitive to changes in bowel preparation with higher MNA among those with good bowel preparation compared with those with poor preparation. Our evidence suggests MNA was particularly sensitive when restricted to only those in whom adenomas were seen.

A randomized controlled trial comparing a low-residue diet versus clear liquids for colonoscopy preparation: impact on tolerance, procedure time, and adenoma detection rate

OBJECTIVE

To achieve an excellent bowel preparation, it is routine to require a clear liquid diet on the day before the procedure. Unfortunately, this dietary modification may be poorly tolerated. We examine whether a change in precolonoscopy dietary restriction can lead to better patient tolerance without compromising examination quality.

METHODS

This is a prospective, blinded, randomized controlled trial of patients undergoing screening or surveillance colonoscopy. The primary objective measures the effect of dietary modification on bowel prep quality. Secondary endpoints include polyp detection, patient tolerance, withdrawal time, and patient acceptance. A total of 200 patients were randomized to either (a) a low-residue diet for breakfast and lunch the day before the procedure or (b) clear liquids all day before the procedure. All patients underwent an identical low-volume sodium sulfate split prep. Bowel prep quality was scored using the Boston Bowel Preparation Scale (BBPS). A t test with TOST was used for noninferiority. Secondary endpoints were compared using χ analysis.

RESULTS

Overall, 96.5% of patients had a good or excellent bowel prep (BBPS=6, 7, 8, or 9). LRD prep quality was noninferior to CLD prep quality (LRD 7.8 vs. CLD 8.1). Polyp detection rates were similar (68% vs. 65.4%, P=0.6899). Patient tolerance and acceptance did not differ. Withdrawal times were equivalent between both groups (16.2 vs. 16.5 min, P=NS).

CONCLUSIONS

Patients allowed to have a limited low-residue diet before colonoscopy achieve a bowel prep quality that is noninferior to patients on a strict clear liquid diet limitation. Furthermore, polyp detection rates, patient tolerance, and patient acceptance were similar between the 2 groups.

Impact of fair bowel preparation quality on adenoma and serrated polyp detection: data from the New Hampshire colonoscopy registry by using a standardized preparation-quality rating

BACKGROUND

The effect of colon preparation quality on adenoma detection rates (ADRs) is unclear, partly because of lack of uniform colon preparation ratings in prior studies. The New Hampshire Colonoscopy Registry collects detailed data from colonoscopies statewide, by using a uniform preparation quality scale after the endoscopist has cleaned the mucosa.

OBJECTIVE

To compare the overall and proximal ADR and serrated polyp detection rates (SDR) in colonoscopies with differing levels of colon preparation quality.

DESIGN

Cross-sectional.

SETTING

New Hampshire statewide registry.

PATIENTS

Patients undergoing colonoscopy.

INTERVENTIONS

We examined colon preparation quality for 13,022 colonoscopies, graded by using specific descriptions provided to endoscopists. ADR and SDR are the number of colonoscopies with at least 1 adenoma or serrated polyp (excluding those in the rectum and/or sigmoid colon) detected divided by the total number of colonoscopies, for the preparation categories: optimal (excellent and/or good), fair, and poor.

MAIN OUTCOME MEASUREMENTS

Overall/proximal ADR/SDR.

RESULTS

The overall detection rates in examinations with fair colon preparation quality (SDR 8.9%; 95% confidence interval [CI], 7.4-10.7, ADR 27.1%; 95% CI, 24.6-30.0) were similar to rates observed in colonoscopies with optimal preparation quality (SDR 8.8%; 95% CI, 8.3-9.4, ADR 26.3%; 95% CI, 25.6-27.2). This finding also was observed for rates in the proximal colon. A logistic regression model (including withdrawal time) found that proximal ADR was statistically lower in the poor preparation category (odds ratio 0.45; 95% CI, 0.24-0.84; P < .01) than in adequately prepared colons.

LIMITATIONS

Homogeneous population.

CONCLUSION

In our sample, there was no significant difference in overall or proximal ADR or SDR between colonoscopies with fair versus optimal colon preparation quality. Poor colon preparation quality may reduce the proximal ADR.

Efficacy of morning-only 4 liter sulfa free polyethylene glycol vs 2 liter polyethylene glycol with ascorbic acid for afternoon colonoscopy

AIM

To compare the bowel cleansing efficacy of same day ingestion of 4-L sulfa-free polyethylene glycol (4-L SF-PEG) vs 2-L polyethylene glycol solution with ascorbic acid (2-L PEG + Asc) in patients undergoing afternoon colonoscopy.

METHODS

206 patients (mean age 56.7 years, 61% male) undergoing outpatient screening or surveillance colonoscopies were prospectively randomized to receive either 4-L SF-PEG (n = 104) or 2-L PEG + Asc solution (n = 102). Colonoscopies were performed by two blinded endoscopists. Bowel preparation was graded using the Ottawa scale. Each participant completed a satisfaction and side effect survey.

RESULTS

There was no difference in patient demographics amongst groups. 4-L SF-PEG resulted in better Ottawa scores compared to 2-L PEG + Asc, 4.2 vs 4.9 (P = 0.0186); left colon: 1.33 vs 1.57 respectively (P = 0.0224), right colon: 1.38 vs 1.63 respectively (P = 0.0097). No difference in Ottawa scores was found for the mid colon or amount of fluid. Patient satisfaction was similar for both arms but those assigned to 4-L SF-PEG reported less bloating: 23.1% vs 11.5% (P = 0.0235). Overall polyp detection, adenomatous polyp and advanced adenoma detection rates were similar between the two groups.

CONCLUSION

Morning only 4-L SF-PEG provided superior cleansing with less bloating as compared to 2-L PEG + Asc bowel preparation for afternoon colonoscopy. Thus, future studies evaluating efficacy of morning only preparation for afternoon colonoscopy should use 4-L SF-PEG as the standard comparator.

Randomized trial of 2-L polyethylene glycol + ascorbic acid versus 4-L polyethylene glycol as bowel cleansing for colonoscopy in an optimal setting

BACKGROUND AND AIM

Prior studies have reported 2-L polyethylene glycol (PEG) plus ascorbic acid (PEG + Asc) is an effective alternative to standard 4-L PEG for bowel preparation before colonoscopy, but they are limited because of some confounders. Therefore, we compared the efficacy, patient compliance, satisfaction, and safety of 2-L PEG + Asc versus 4-L PEG for bowel cleansing in optimal preparation strategies.

METHODS

In this prospective, randomized, single-blind trial, consenting outpatients were randomly assigned to one of two arms. All colonoscopies were scheduled in the morning and cleansing solutions were administered as a split-dose regimen. Bowel-cleansing efficacy in three different segments was measured on a five-point scale with four-point overall grading. Patients' opinions of the preparation regimens were obtained by questionnaire.

RESULTS

There was no significant difference between the 2-L PEG + Asc (159/163; 97.5%) and 4-L PEG (162/164; 98.8%) with respect to the overall success of bowel cleansing (mean difference = -1.3 [-4.1-∞]). Patient compliance, acceptability, and satisfaction were better in the 2-L PEG + Asc arm than the 4-L PEG arm (P < 0.05). Additionally, the incidence of side effects was lower in the 2-L PEG + Asc than the 4-L PEG (overall, 57.7% vs 73.2%, P < 0.05). However, no significant difference was seen in patients' rating of taste.

CONCLUSIONS

In an optimal preparation setting, 2-L PEG + Asc has equal efficacy as a bowel cleanser prior to colonoscopy as 4-L PEG, with the advantages of better patient compliance, satisfaction, and safety.

The inulin hydrogen breath test predicts the quality of colonic preparation

BACKGROUND

Successful bowel preparation is essential to an adequate performance of colonoscopy. Polyethylene glycol (PEG) with electrolyte solutions induces diarrhea with depletion of substrates fermentable by hydrogen (H2)-producing colonic microbiota. Inulin has recently been suggested as a prebiotic substrate for the H2 breath test because it is resistant to intestinal hydrolysis and is fermented mostly by the colonic bacteria. This study aimed to assess time-dependent changes in H2 breath levels in order to predict the colonic preparation of patients scheduled for colonoscopy with or without oral supplementation of inulin.

METHODS

In this prospective nonrandomized trial, 127 subjects drank 4 l of PEG 280-mg solution as bowel preparation for colonoscopy. A subgroup of 31 patients also ingested inulin (10 g in 200 ml of water) at breakfast as an additional substrate to increase colonic H2 production. Measurements of H2 breath levels were performed immediately before and after colonic preparation. As the main outcome measure, the quality of the colonic preparation was scored as excellent to fair (i.e., clean bowel allowing successful pan-colonoscopy, including the terminal ileum) or poor (incomplete colonoscopy due to fecal debris).

RESULTS

The H2 breath levels decreased from 11.0 ± 1.8 ppm before PEG to 1.8 ± 0.3 ppm after PEG (n = 18; P < 0.001). The H2 concentrations after PEG ingestion were significantly lower (P < 0.001) in the patients with excellent-to-fair preparation than in the 19 patients with poor preparation. Ingestion of inulin induced an overall increase in H2 breath levels and improved discrimination between the patients with excellent-to-fair colonic preparation and those with poor preparation, leading to the sensitivity and specificity of such a test reaching 100 %.

CONCLUSIONS

The H2 breath test with inulin ingestion can be a simple, noninvasive, reliable method for predicting successful colonic preparation that leads to cost savings and less patient discomfort/stress or need to repeat colonoscopy.

Colonoscopy quality: metrics and implementation

Colonoscopy is an excellent area for quality improvement because it is high volume, has significant associated risk and expense, and there is evidence that variability in its performance affects outcomes. The best end point for validation of quality metrics in colonoscopy is colorectal cancer incidence and mortality, but a more readily accessible metric is the adenoma detection rate. Fourteen quality metrics were proposed in 2006, and these are described in this article. Implementation of quality improvement initiatives involves rapid assessments and changes on an iterative basis, and can be done at the individual, group, or facility level.

Pilot validation of the Boston Bowel Preparation Scale in China

BACKGROUND AND AIM

The Boston Bowel Preparation Scale (BBPS) is a novel bowel cleanliness rating scale that has undergone validation at Boston University Medical Center, Boston, MA, USA. Thus far, there is no standard recognized bowel preparation scale in China. The aim of the present study was to analyze the reliability and validity of the BBPS for the assessment of bowel preparation quality (BPQ) in China.

METHODS

A group of 49 participants from several hospitals in Guangdong province viewed a video demonstration of BBPS provided by Boston Medical Center and participated in a continuing education seminar. Inter-observer reliability was assessed for three testing colonoscopies in the video. Three months later, 13 of the participants repeated the test, and intra-observer reliability was assessed. The BBPS was then applied prospectively in 1012 screening colonoscopies and BBPS scores were compared with polyp-detection rate. Intraclass correlation coefficients (ICC) and weighted Kappa values assessed inter- and intra-rater reliability, respectively. The association of BBPS scores with polyp-detection rates was calculated by χ(2) tests.

RESULTS

The inter-observer ICC of BBPS scores was 0.987 (95% CI, 0.949-1.0). The weighted Kappa for BBPS scores was 0.671 (95%CI, 0.507-0.841). For 1012 screening colonoscopies, the mean BBPS score was 6.9 ± 1.8. BBPS scores ≥ 5 were associated with a higher polyp-detection rate (35%) than scores < 5 (18%) (P < 0.05).

CONCLUSION

The BBPS is a valid and reliable measure of BPQ, and this validity and reliability was maintained for Chinese physicians taught via video.

Shorter preparation to procedure interval for colonoscopy improves quality of bowel cleansing

BACKGROUND

The timing of bowel preparation for colonoscopy influences the quality of bowel cleansing and the success of the procedure.

AIM

We aimed to determine whether the interval between the end of bowel preparation and the start of colonoscopy influences preparation quality.

METHODS

We retrospectively analysed 1785 colonoscopies performed between January 2010 and January 2011. The quality of bowel cleansing was compared between those who had a less than 8-h interval between the end of bowel preparation to the start of the procedure versus those who had a greater than 8-h interval. Univariate and multivariate logistic regression analyses evaluated quality of bowel cleansing, preparation to procedure time, age, gender, hospital inpatient or outpatient status, indication for colonoscopy, caecal intubation rate, and segmental polyp detection.

RESULTS

Fifty-three per cent of the cohort was male. Eighty-nine per cent were outpatients. Bowel cleansing was reported as satisfactory/good in 87% and poor in 13%. A <8-h preparation to procedure time was associated with a higher rate of satisfactory/good cleansing than a >8-h interval (odds ratio (OR) 1.3, P = 0.04). In a multivariate analysis, female gender (OR 1.4, P = 0.02), outpatient status (OR 3.1 P = 0.001) and indication for procedure (P < 0.01) were significant predictors of adequate bowel preparation. Adequate bowel preparation was associated with a significant increase in caecal intubation rates (OR 5.3, P = 0.001).

CONCLUSIONS

A shorter (<8 h) interval between end of bowel preparation and start of colonoscopy yielded better bowel cleansing than a longer (>8 h) interval. Adequate bowel preparation led to improved caecal intubation rates.

The Effect of the Bowel Preparation Status on the Risk of Missing Polyp and Adenoma during Screening Colonoscopy: A Tandem Colonoscopic Study

Background/Aims

Although a small amount of fecal material can obscure significant colorectal lesions, it has not been well documented whether bowel preparation status affects the missing risk of colorectal polyps and adenomas during a colonoscopy.

Methods

We prospectively enrolled patients with one to nine colorectal polyps and at least one adenoma of >5 mm in size at the screening colonoscopy. Tandem colonoscopy with polypectomy was carried out within 3 months.

Results

A total of 277 patients with 942 polyps and 714 adenomas completed index and tandem examinations. At the index colonoscopy, 187 polyps (19.9%) and 127 adenomas (17.8%) were missed. The per-patient miss rate of polyps and adenomas increased significantly as the bowel cleansing rate declined from excellent to poor/inadequate on the Aronchick scale (polyps, p=0.024; adenomas, p=0.040). The patients with poor/inadequate bowel preparation were independently associated with an increased risk of having missed polyps (odds ratio [OR], 3.21; 95% confidence interval [CI], 1.13 to 9.15) or missed adenomas (OR, 3.04; 95% CI, 1.04 to 8.88) compared to the patients with excellent bowel preparation.

Conclusions

The risk of missing polyps and adenomas during screening colonoscopy is significantly affected by bowel preparation status. It seems appropriate to shorten the colonoscopy follow-up interval for patients with suboptimal bowel preparation.

Inflammatory bowel disease cancer risk, detection and surveillance

Ulcerative colitis (UC) is a chronic and relapsing inflammation of the colonic mucosa with variable extension from the rectum towards the cecum. The aim of medical treatment is to induce and maintain clinical remission. If no remission can be achieved, continuous inflammation may repeatedly destroy the epithelial cells. This has to be compensated by epithelial increased proliferation which finally can lead to inflammation-associated colorectal cancer (CRC). The risk of colitis-associated CRC is increased after a long disease duration, especially in patients with chronic active disease. This risk may be lower if long-lasting mucosal healing can be achieved. To detect the development of dysplasia/intraepithelial neoplasia and colitis-associated CRC early, surveillance programs have been installed. However, the evidence of success for those surveillance programs is limited. This is partially due to problems of detecting precancerous lesions in the colonic mucosa during those surveillance programs. The specific problems of surveillance programs for the prevention of CRC and specific aspects of patient care in UC are reviewed in this article.

Endoscopic detection of colorectal adenomas: standards and sophisticated methods

Colorectal cancer represents one of the leading malignancies worldwide. Early endoscopic detection and removal of its precursor lesions, adenomas, and serrated hyperplastic polyps results in a decrease of colon cancer-related death. However, miss rates in adenoma detection up to 26% underline the need for high compliance to basic measures and further improvement in methodology and technology. Basic parameters affecting adenoma detection rates include sufficient training and awareness of the endoscopist, use of high-definition endoscopes, careful examination behind folds, cleansing the colon wall, accurate distention of the colon, and adequate withdrawal time. Advanced imaging techniques, introduced to further improve adenoma detection, have yielded mixed results. These include wide-angle colonoscopes, cap-assisted colonoscopy, and retroscopic methods which may add new obstacles to colonoscopy. Moreover, chromoendoscopy either 'virtual' or by topically applied dyes has been suggested to enhance the detection of colonic neoplasia. Yet, studies on patients with average cancer risk have failed to reproduce promising initial results. Similarly, although autofluorescence has not enhanced the diagnostic yield in screening a population at average risk, it may be useful in patients at increased cancer risk. Recently, technical feasibility of molecular imaging employing 'biomarkers' has been demonstrated, but needs further evaluation. The newest developments, employing light-scattering spectroscopy, suggest the existence of a 'field effect' of colonic carcinogenesis and may enable detection of the earliest neoplastic events and distant adenomas even when applied to normal-appearing mucosa. Upon confirmation, these technologies may result in a substantial change in patient management and risk stratification.

The effect of colonoscopy preparation quality on adenoma detection rates

BACKGROUND

Colonoscopy reduces the risk of colorectal cancer mortality by removing precancerous adenomas. The detection rate of subcentimeter (<10 mm) polyps is lower for procedures with inadequate preparation quality.

OBJECTIVE

To compare the adenoma detection rates of small (6-9 mm) and diminutive (≤ 5 mm) adenomas in patients with poor and fair quality preparations with those with adequate quality preparations.

DESIGN

Cross-sectional study and multivariable, hierarchical model.

SETTING

Roudebush Veterans Affairs Medical Center.

PATIENTS

This study involved 8800 colonoscopies performed from 2001 to 2010.

MAIN OUTCOME MEASUREMENTS

Preparation quality rating, polyp size, and polyp histology.

RESULTS

Preparation quality was rated as fair in 2809 (31.9%) and poor in 829 (9.4%) colonoscopies. In patients with poor compared with adequate quality, the detection rate was lower for diminutive adenomas (odds ratio [OR] 0.57; 95% CI, 0.47-0.70) but not for small adenomas (OR 0.84; 95% CI, 0.65-1.07). There were no differences in the detection rate of diminutive (OR 1.08; 95% CI, 0.94-1.24]) or small (OR 1.09; 95% CI, 0.94-1.27) adenomas in patients with fair compared with adequate quality preparation. Detection of advanced histology in patients with poor preparation quality was lower than in those with adequate quality (P = .027; 3.3% vs 5.0%), but there was no difference in those with fair compared with adequate quality (P = .893; 4.9% vs 5.0%).

LIMITATIONS

Single-center study; no standardization of preparation quality or size measurements.

CONCLUSIONS

A fair preparation quality rating does not decrease the detection rate for adenomas of any size or for advanced histology, suggesting that fair quality may be considered adequate and that follow-up intervals may not need to be shortened. Poor preparation quality decreases the detection rate of diminutive adenomas and advanced histology, suggesting substandard colonoscopy performance.

Same-day bowel cleansing regimen is superior to a split-dose regimen over 2 days for afternoon colonoscopy: results from a large prospective series

GOALS AND BACKGROUND

Conventional bowel preparation for afternoon colonoscopy requires an oral agent the day before the procedure. Bowel cleansing given only on the day of the colonoscopy has never been attempted. The aims of this study were to compare the efficacy of bowel cleansing, impact on activities of daily living (ADLs), side effects, and patient preference of a same-day regimen with a 2-day regimen.

STUDY

A single-blinded, prospective cohort study. Patients were block recruited into 2 groups with the endoscopist blinded to the regimen. Group A: 3 sachets of sodium picosulphate given at 12:00 noon and at 05:00 PM the day before and at 8:00 AM on the morning of the procedure. Group B: 2 sachets of sodium picosulphate on the morning of the procedure at 07:00 and 10:00 AM. Patients completed a quality-of-life questionnaire investigating the side effects, impact on ADLs, and regimen preference. The main outcome measures were mucosal cleansing, impact on ADLs, side effects, and patient preference of the regimen.

RESULTS

A total of 227 patients underwent screening colonoscopy. There were 95 patients in group A and 132 in group B, all of whom were age and sex matched. Same-day preparation produced better mucosal cleansing (P = 0.0046) with fewer side effects (P = 0.002). Impact on ADLs was less with the same-day regimen (P < 0.0001). Significantly more number of patients preferred the same-day preparation compared with the 2-day regimen (P = 0.0147).

CONCLUSIONS

Same-day bowel preparation is feasible, safe, and more effective than a split-dose regimen. It has fewer adverse events and is preferred by patients.

An unmet medical need: advances in endoscopic imaging of colorectal neoplasia

Gastrointestinal cancer is a major public health problem worldwide. Detection of early neoplastic lesions in gastrointestinal tract is essential for cure, because prognosis and survival are related to the size and stage of malignant lesions. Endoscopic screening and treatment of polyps could prevent approximately 80% of colorectal cancer (CRC). However, white-light endoscopy is an imperfect technology since miss rates of up to 25% have been reported and polyps without malignant potential were treated without benefit but with additional costs and risks to the patient. There are several known "human" predictors of an inadequate colonoscopy. These include patient characteristics such as poor bowel preparation, female gender, or inpatient status. Skills of the endoscopists are also an important issue. Therefore, a variety of advanced technologies has been attempted to overcome these issues. These new endoscopic imaging techniques allow a more precise classification of mucosal alterations with selection of patients for invasive therapy or surveillance. Further, molecular and functional imaging techniques could identify novel targets for therapies and new prospects to access response to therapies. However, at the "end of the day" a better endoscopic approach for CRC screening and surveillance depends on a good bowel preparation, a trained endoscopist spending sufficient time on a detailed examination together with an advanced endoscope.

Appointment waiting times and education level influence the quality of bowel preparation in adult patients undergoing colonoscopy

Background

Risk factors for poor bowel preparation are recognized to be independent of the type of bowel preparation method used. Patient and administrative factors influencing bowel preparation are known to vary in different healthcare systems.

Methods

A prospective, cross-sectional study of patients undergoing colonoscopy in an Asian tertiary centre was conducted to identify risk factors associated with poor bowel preparation, and to evaluate the impact of poor bowel preparation on technical performance and patient comfort.

Results

Data on 501 patients (mean age 60.1 ± 14.0 years old, 51.2% males, 60.9% with secondary education or higher) was available for analysis. Poor bowel preparation was present in 151 patients (30.1%). Lower education level (OR = 2.35, 95% CI = 1.54 - 3.60), colonoscopy appointment waiting time beyond 16 weeks (OR = 1.86, 95% CI = 1.04 - 3.37) and non-adherence to bowel preparation instructions (OR = 4.76, 95% CI = 3.00 - 7.55) were identified as independent risk factors for poor bowel preparation. Poor bowel preparation was associated with a lower cecal intubation rate (78.1% versus 98.3%, p < 0.001), prolonged total colonoscopy time (25.4 ± 12.6 minutes versus 16.7 ± 10.2 minutes, p < 0.001), and increased patient discomfort during colonoscopy (patient with moderate to severe abdominal discomfort 31.8% versus 3.2%, p < 0.001).

Conclusions

Education levels and appointment waiting times, in addition to non-adherence to bowel preparation instructions, increase the risk of poor bowel preparation in adult patients undergoing colonoscopy. The latter has a significant impact on colonoscopy performance and patient comfort.

An endoscopist-blinded, randomized, controlled trial of a simple visual aid to improve bowel preparation for screening colonoscopy

BACKGROUND

The effect of patient education on bowel preparation for colonoscopy has not been well studied. An improvement in patient understanding of the rationale for bowel preparation before colonoscopy might enhance adherence to the prescribed bowel regimen and improve bowel preparation quality.

OBJECTIVE

To measure the effect of a simple educational intervention on the quality of bowel preparation during colonoscopy.

DESIGN

Prospective, single-center, endoscopist-blinded, randomized, controlled trial.

SETTING

Tertiary-care center.

PATIENTS

This study involved outpatients directly referred for screening colonoscopy.

INTERVENTION

Inclusion of a visual aid depicting both clean and dirty colons in addition to standard written colonoscopy instructions.

MAIN OUTCOME MEASUREMENTS

The primary outcome was the quality of the bowel preparation according to the Boston Bowel Preparation Scale (BBPS). Secondary outcomes included the need for repeat colonoscopy because of inadequate bowel preparation, insertion and withdrawal time, polyps detected, and patient tolerance of bowel preparation and colonoscopy.

RESULTS

We analyzed 492 patients given a visual aid and 477 controls. The percentage of colonoscopies with a BBPS score≥5 was similar in both groups (91% visual aid vs 89% control, P=.43). The odds ratio for having a BBPS≥5 in the visual aid group was 1.24 (95% CI, 0.83-1.87) compared with controls. Other secondary outcomes were similar between groups.

LIMITATIONS

Single-center study.

CONCLUSION

A simple card with photographs and text explaining the rationale for bowel preparation did not change the quality of bowel preparation in patients directly referred for screening colonoscopy. Future educational studies may need to include more interactive or intensive methods. (

CLINICAL TRIAL REGISTRATION NUMBER

NCT00643682.).

Impact of low-residue diet on bowel preparation for colonoscopy

BACKGROUND

Few studies have focused on the effect of dietary residue on preparation for colonoscopy.

OBJECTIVE

To determine the impact of a low-residue diet on the quality of bowel preparation.

SETTING

Chang Gung Memorial Hospital, Kaohsiung Medical Center, Taiwan.

PATIENTS

Eight hundred four consecutive patients (50.4 ± 11.6 y (range, 18-88 y), 43.6% female) undergoing colonoscopy between May 2008 and June 2009.

INTERVENTION

Subjects were advised to consume a low-residue diet for 2 days before the procedure, and they recorded food intake by use of diet diaries.

MAIN OUTCOME MEASURES

The quality of bowel cleansing was evaluated using the Ottawa bowel preparation scale. Patient variables and details of each procedure were recorded, and factors that determined the quality of colon cleansing were determined.

LIMITATIONS

Categories of foods consumed were recorded, but not the amount eaten, and diet diaries were completed retrospectively.

RESULTS

Data from 789 patients were analyzed. Only 44.2% of patients adhered to a low-residue diet, and 39.3% of patients were inadequately prepared. On multivariate logistic regression analysis, age (P = .007), body mass index (P = .01), abdominal girth (P = .041), bowel habit tending to constipation (P = .015), and high-residue diet (P < .0001) were independent predictors of inadequate bowel preparation. There was a linear relationship between dietary residue score and bowel cleanliness score (r = -0.475; P < .001).

CONCLUSIONS

A low-residue diet for 2 days of before colonoscopy improves bowel cleansing, but compliance with this advice is poor. The importance of a low-residue diet should be emphasized to patients undergoing preparation for colonoscopy.

Morning-only one-gallon polyethylene glycol improves bowel cleansing for afternoon colonoscopies: a randomized endoscopist-blinded prospective study

OBJECTIVES

Inadequate bowel preparation is a known factor associated with increased failure rates of afternoon colonoscopy and lower adenoma detection rates. The aim of our study was to compare the efficacy of bowel cleansing achieved by administering 1-gallon (4 l) polyethylene glycol (PEG) preparation to patients in the morning of an afternoon colonoscopy with that of the traditional evening regimen.

METHODS

A prospective endoscopist-blinded study was conducted, in which patients undergoing afternoon colonoscopy were randomized to receive either 1 gallon of PEG the evening before the procedure or the morning of the colonoscopy. Bowel cleansing efficacy was scored by a blinded endoscopist using the Ottawa scale and each participant filled out a satisfaction survey. Mean scores for each bowel segment, composite mean scores, and rates of "good prep" interpreted from the Ottawa scale were compared between the two groups.

RESULTS

A total of 136 patients (mean age 51.8 years, 52.2% men) evenly distributed between the two groups formed the study sample. Patients in the morning group had significantly lower Ottawa scale scores and were more likely to have a good preparation for each bowel segment and overall when compared with the evening group (P<0.01). Moreover, patients in the morning group were over 50% less likely to lose sleep or have bloating compared with the evening group (P<0.05). There was no difference in the study groups on overall polyp detection rate, adenomatous polyps, or number of patients with adenomas.

CONCLUSIONS

This study shows that the bowel cleansing efficacy of morning-only 1-gallon PEG is superior and better tolerated compared with consumption of 1-gallon PEG in the evening before the day of an afternoon colonoscopy. Thus, administering 1-gallon PEG solution in the morning of an afternoon colonoscopy is a feasible option that can improve the quality of an afternoon colonoscopy.

Clinical trial: 2-L polyethylene glycol-based lavage solutions for colonoscopy preparation - a randomized, single-blind study of two formulations

BACKGROUND

The 2-L polyethylene glycol (PEG) lavage solutions provide efficacy similar to that of standard 4-L PEG formulations in spite of the reduced volume. The comparative efficacy and tolerability of two formulations of 2-L PEG solution remain unknown.

AIMS

To assess the efficacy, safety and tolerability of PEG + Bis compared with PEG + Asc, and to study the effect of bowel cleansing quality on adenoma detection rates.

METHODS

Patients were randomized to receive either 2-L PEG with ascorbic acid (PEG + Asc) or 2-L PEG plus bisacodyl 10 mg (PEG + Bis). The primary endpoint was overall colon cleansing score, assessed by blinded investigators using a validated four-point scale. Secondary endpoints included adenoma detection rate, patient tolerability and compliance and adverse events.

RESULTS

Fifty-two patients received PEG + Asc and 55 patients received PEG + Bis. Overall colon cleansing scores (+/-s.d.) were 1.40 +/- 0.69 and 1.75 +/- 0.70 (P < 0.003) in the PEG + Asc and PEG + Bis groups, respectively. Excellent and good ratings were recorded in 69% and 23% receiving PEG + Asc compared to 38% and 51% (P = 0.01) of patients receiving PEG + Bis. More adenomas were detected in colonoscopies performed with PEG + Asc (39%) than in those performed with PEG + Bis (20%) (P = 0.04). Patient tolerability and safety were similar with both preparations.

CONCLUSION

The use of PEG + Asc resulted in better colon cleansing and higher adenoma detection rates compared with PEG + Bis.

A feasibility study of probiotics pretreatment as a bowel preparation for colonoscopy in constipated patients

BACKGROUND

The use of probiotics to treat constipation is based on the premise that supplying the gut with healthy bacteria in the form of probiotics can help normalize intestinal function. The aim of this study was to determine the efficacy of a 2-week probiotics pretreatment with oral sodium phosphate (NaP) for bowel cleansing before colonoscopy in patients with constipation.

METHODS

Patients with constipation were prospectively randomized to receive a 2-week probiotics course comprising a mixture of Bacillus subtilis and Streptococcus faecium (group A, n = 51) or placebo (group B, n = 53) with an oral NaP solution. During the same period, another 107 patients with normal bowel movement were enrolled and received the probiotics treatment (n = 53, group C) or placebo (n = 54, group D). The primary outcome measure was the quality of bowel cleansing. Postendoscopic symptoms were estimated using a visual analogue scale.

RESULTS

Patients having normal defecation presented with better bowel preparation than those with constipation (57.9% versus 37.5%; P = 0.003). Probiotics pretreatment (group A) was more effective at bowel cleansing for colonoscopy compared with placebo (group B) in constipated patients (54.9% versus 20.8%; P < 0.001). In contrast, preparation quality did not differ significantly between groups C and D. Preparation-related adverse events and postendoscopic symptoms were more frequent and severe in group B than in group A.

CONCLUSION

Two weeks of probiotics pretreatment as part of bowel preparation significantly improves colonic mucosa visualization during colonoscopy and reduces preparation-related and postendoscopic gastrointestinal symptoms in constipated patients.

Capsule endoscopy versus colonoscopy for the detection of polyps and cancer

BACKGROUND

An ingestible capsule consisting of an endoscope equipped with a video camera at both ends was designed to explore the colon. This study compared capsule endoscopy with optical colonoscopy for the detection of colorectal polyps and cancer.

METHODS

We performed a prospective, multicenter study comparing capsule endoscopy with optical colonoscopy (the standard for comparison) in a cohort of patients with known or suspected colonic disease for the detection of colorectal polyps or cancer. Patients underwent an adapted colon preparation, and colon cleanliness was graded from poor to excellent. We computed the sensitivity and specificity of capsule endoscopy for polyps, advanced adenoma, and cancer.

RESULTS

A total of 328 patients (mean age, 58.6 years) were included in the study. The capsule was excreted within 10 hours after ingestion and before the end of the lifetime of the battery in 92.8% of the patients. The sensitivity and specificity of capsule endoscopy for detecting polyps that were 6 mm in size or bigger were 64% (95% confidence interval [CI], 59 to 72) and 84% (95% CI, 81 to 87), respectively, and for detecting advanced adenoma, the sensitivity and specificity were 73% (95% CI, 61 to 83) and 79% (95% CI, 77 to 81), respectively. Of 19 cancers detected by colonoscopy, 14 were detected by capsule endoscopy (sensitivity, 74%; 95% CI, 52 to 88). For all lesions, the sensitivity of capsule endoscopy was higher in patients with good or excellent colon cleanliness than in those with fair or poor colon cleanliness. Mild-to-moderate adverse events were reported in 26 patients (7.9%) and were mostly related to the colon preparation.

CONCLUSIONS

The use of capsule endoscopy of the colon allows visualization of the colonic mucosa in most patients, but its sensitivity for detecting colonic lesions is low as compared with the use of optical colonoscopy. (ClinicalTrials.gov number, NCT00604162.)