Multicenter, randomized study to optimize bowel preparation for colon capsule endoscopy

What Is the Optimal Bowel Preparation for Capsule Colonoscopy and Pan-intestinal Capsule Endoscopy? A Systematic Review and Meta-Analysis

BACKGROUND

The rate of adequate cleansing (ACR) and complete examinations (CR) are key quality indicators in capsule colonoscopy (CC) and pan-intestinal capsule endoscopy (PCE).

AIMS

To evaluate the efficacy of bowel preparation protocols regarding ACR and CR.

METHODS

We conducted a systematic review and meta-analysis, search terms regarding colon capsule preparation, publication date from 2006/01, and date of search 2021/12, in six bibliographic databases. Multiple steps of the cleansing protocol were assessed: diet, adjunctive laxatives, purgative solution, use of prokinetic agents, and "booster". The meta-analytical frequency of ACR and CR was estimated, and subgroup analyses performed. Strategies associated with higher ACR and CR were explored using meta-analytical univariable and multivariable regression models.

RESULTS

Twenty-six observational studies and five RCTs included (n = 4072 patients). The pooled rate of ACR was 72.5% (95% C.I. 67.8-77.5%; I2 = 92.4%), and the pooled rate of CR was 83.0% (95% C.I. 78.7-87.7%; I2 = 96.5%). The highest ACR were obtained using a low-fibre diet [78.5% (95% C.I. 72.0-85.6%); I2 = 57.0%], adjunctive laxatives [74.7% (95% C.I. 69.8-80.1%); I2 = 85.3%], and split dose < 4L polyethylene glycol (PEG) as purgative [77.5% (95% C.I. 68.4-87.8%); I2 = 47.3%]. The highest CR were observed using routine prokinetics prior to capsule ingestion [84.4% (95% C.I. 79.9-89.2%); I2 = 89.8%], and sodium phosphate (NaP) as "booster" [86.2% (95% C.I. 82.3-90.2%); I2 = 86.8%]. In univariable models, adjunctive laxatives were associated with higher ACR [OR 1.81 (95% C.I. 1.13; 2.90); p = 0.014]. CR was higher with routine prokinetics [OR 1.86 (95% C.I. 1.13; 3.05); p = 0.015] and split-dose PEG purgative [OR 2.03 (95% C.I. 1.01; 4.09), p = 0.048].

CONCLUSIONS

Main quality outcomes (ACR, CR) remain suboptimal for CC and PCE. Despite considerable heterogeneity, our results support low-fibre diet, use of adjunctive sennosides, split dose < 4L PEG, and routine prokinetics, while NaP remains the most consistent option as booster.

Clinical utility of colon capsule endoscopy: a moving target?

The purpose of this article is to provide an overview of white light colon capsule endoscopy's current clinical application, concentrating on its most recent developments. Second-generation colon capsule endoscopy (CCE2) is approved by the FDA for use as an adjunctive test in patients with incomplete colonoscopy and within Europe in patients at average risk, those with incomplete colonoscopies or those unwilling to undergo conventional colonoscopies. Since the publication of European Society of GI Endoscopy guidelines on the use of CCE, there has been a significant increase in comparative studies on the diagnostic yield of CCE. This paper discusses CCE2 in further detail. It explains newly developed colon capsule system and the current status on the use of CCE, it also provides a comprehensive summary of systematic reviews on the implementation of CCE in colorectal cancer screening from a methodological perspective. Patients with ulcerative colitis can benefit from CCE2 in terms of assessing mucosal inflammation. As part of this review, performance of CCE2 for assessing disease severity in ulcerative colitis is compared with colonoscopy. Finally, an assessment if CCE can become a cost-effective clinical service overall.

An evaluation of a novel bowel preparation regimen and its effect on the utility of colon capsule endoscopy: a prospective cohort study with historical controls

BACKGROUND

The aim of this study was to evaluate the efficacy of a novel bowel preparation and booster regimen for colon capsule endoscopy (CCE) using macrogol, phospho-soda and gastrografin, compared with a control regimen consisting of polyethylene glycol and sodium picosulfate.

METHODS

This was a prospective cohort study using historical controls. Symptomatic patients undergoing CCE between 11/07/2021 and 21/12/2021 using the novel regimen were included. Symptomatic patients who underwent CCE in the ScotCap evaluation using the control regimen were used as historical controls. We measured the rate of complete test (visualisation of the whole colon and rectum), adequate bowel preparation, successful test (complete and adequate bowel preparation) and need for further test following CCE. The rate of adverse events was also collected.

RESULTS

Patients undergoing CCE using the new and control regimen were 200 and 316, respectively. The median age, age range and proportion of female patients in the new and control regimen cohorts was 61 vs 60 years, 16-86 vs 20-83 years, and 60.5% vs 56.6%. The rate of complete test, adequate bowel reparation and successful test for the new and control regimen was 69% vs 72.2%, 86.6% vs 80.7% and 60.5% vs 65.8%. Comparing the new and control regimen, 39.5% vs 37.3% of patients required no test following CCE, 26% vs 32.6% required a colonoscopy, 31.5% vs 21.5% required a flexible sigmoidoscopy and 3% vs 2.9% required a computed tomography colonogram. No adverse events were reported using the new regimen compared to 2 (0.6%) in the control group.

CONCLUSIONS

The rate of adequate bowel preparation has improved following the introduction of a new regimen. However, further work is needed to increase the complete test rate. A significant proportion of patients continue to avoid colonoscopy following CCE.

CC-CLEAR (Colon Capsule Cleansing Assessment and Report): the novel scale to evaluate the clinical impact of bowel preparation in capsule colonoscopy - a multicentric validation study

BACKGROUND

Colon Capsule Cleansing Assessment and Report (CC-CLEAR) is a novel quantitative bowel preparation scale for colon capsule.

AIM

The aim of this study is to validate the association between CC-CLEAR's classification and major CC outcomes: lesion detection rate, surveillance recommendations and post-CC endoscopic treatment.

METHODS

Multicentric cohort of consecutive CCs. An expert's panel decided post-CC recommendations. Data included CC-CLEAR and Leighton-REX scales. Major CC outcomes were associated with the different cleansing grades.

RESULTS

From 168 CC's included, findings were reported in 123 (73.2%), 67 (54.4%) of those being colorectal polyps. CC-CLEAR influenced CC's lesion detection (OR 1.25 95% IC [1.07-1.46], p-value .004) and polyp detection rate (OR 1.22 95% IC [1.04-1.43], p-value.014). Thirty-two (19%) post-CC colonoscopies were recommended, including 22 (68.75%) with at least one polypectomy. CC-CLEAR was associated with post-CC colonoscopy treatment (OR 1.40 95% IC [1.07-1.84], p-value .015). Regarding surveillance, CC-CLEAR influenced the decision for immediate CC repetition (OR 0.21 95% IC [0.12-0.36], p-value < .001) and the recommendation for CC in 3-5 years' time (OR 1.47 95% IC [1.50-1.86], p-value < .002). The Leighton-Rex scale was not correlated with major CC outcomes.

CONCLUSION

CC-CLEAR impacts major CC outcomes: lesion detection, surveillance recommendations and post-CC endoscopic treatment.

Efficacy of bowel preparation regimens for colon capsule endoscopy: a systematic review and meta-analysis

Background and study aims  Colon capsule endoscopy (CCE) is an alternative to conventional colonoscopy (CC) in specific clinical settings. High completion rates (CRs) and adequate cleanliness rates (ACRs) are fundamental quality parameters if CCE is to be widely implemented as a CC equivalent diagnostic modality. We conducted a systematic review and meta-analysis to investigate the efficacy of different bowel preparations regimens on CR and ACR in CCE. Patients and methods  We performed a systematic literature search in PubMed, Embase, CINAHL, Web of Science, and the Cochrane Library. Data were independently extracted per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The primary outcome measures (CR, ACR) were retrieved from the individual studies and pooled event rates were calculated. Results  Thirty-four observational (OBS) studies (n = 3,789) and 12 randomized clinical trials (RCTs) (n = 1,214) comprising a total 5,003 patients were included. The overall CR was 0.798 (95 % CI, 0.764-0.828); the highest CRs were observed with sodium phosphate (NaP) + gastrografin booster (n = 2, CR = 0.931, 95 % CI, 0.820-0.976). The overall ACR was 0.768 (95 % CI, 0.735-0.797); the highest ACRs were observed with polyethylene glycol (PEG) + magnesium citrate (n = 4, ER = 0.953, 95 % CI, 0.896-0.979). Conclusions  In the largest meta-analysis on CCE bowel preparation regimens, we found that both CRs and ACRs are suboptimal compared to the minimum recommended standards for CC. PEG laxative and NaP booster were the most commonly used but were not associated with higher CRs or ACRs. Well-designed studies on CCE should be performed to find the optimal preparation regimen.

Addition of castor oil as a booster in colon capsule regimens significantly improves completion rates and polyp detection

BACKGROUND

Incomplete excretion rates are problematic for colon capsule endoscopy (CCE). Widely available booster regimens are suboptimal. Recently published data on one day preparation CCE protocol using castor oil appeared effective.

AIM

To assess the impact of adding castor oil to a standard split-dose (2-d) preparation in an unselected Western patient cohort.

METHODS

All patients aged 18 or more referred to our unit for a CCE over a 5-mo period were prospectively recruited. Controls were retrospectively identified from our CCE database. All patients received split bowel preparation with Moviprep^® [polyethylene glycol (PEG)-3350, sodium sulphate, sodium chloride, potassium chloride, sodium ascorbate and ascorbic acid for oral solution; Norgine B. V, United States], a PEG-based solution used predominantly in our colonoscopy practice. Control booster regimen included Moviprep^® with 750 mL of water (booster 1) on reaching the small bowel. A further dose of Moviprep^® with 250 mL of water was given 3 h later and a bisacodyl suppository (Dulcolax^®) 10 mg after 8 h, if the capsule was not excreted. In addition to our standard booster regimen, cases received an additional 15 mL of castor oil given at the time of booster 1. A nested case control design with 2:1 ratio (control:case) was employed. Basic demographics, completion rates, image quality, colonic transit time, diagnostic yield and polyp detection were compared between groups, using a student t or chi-square tests as appropriate.

RESULTS

One hundred and eighty-six CCEs [mean age 60 years (18-97), 56% females, n = 104], including 62 cases have been analysed. Indication breakdown included 96 polyp surveillance (51.6%), 42 lower gastrointestinal symptoms (22.6%), 28 due to incomplete colonoscopy (15%), 18 anaemia (9.7%) and 2 inflammatory bowel disease surveillance (1.1%). Overall, CCE completion was 77% (144/186), image quality was adequate/diagnostic in 91% (170/186), mean colonic transit time was 3.5 h (0.25-13), and the polyp detection rate was 57% (106/186). Completion rates were significantly higher with castor oil, 87% cases (54/62) vs 73% controls (90/124), P = 0.01. The number needed to treat with castor oil to result in an additional complete CCE study was 7, absolute risk reduction = 14.52%, 95% confidence interval (CI): 3.06- 25.97. This effect of castor oil on excretion rates was more significant in the over 60 s, P < 0.03, and in females, P < 0.025. Similarly, polyp detection rates were higher in cases 82% (51/62) vs controls 44% (55/124), P = 0.0001, odds ratio 5.8, 95%CI: 2.77-12.21. Colonic transit times were similar, 3.2 h and 3.8 h, respectively. Image quality was similar, reported as adequate/ diagnostic in 90% (56/62) vs 92% (114/124).

CONCLUSION

In our capsule endoscopy centre, castor oil addition as a CCE booster significantly improved completion rates and polyp detection in an unselected Western cohort.

Lavage, Simethicone, and Prokinetics-What to Swallow with a Video Capsule

The development of new capsules now allows endoscopic diagnosis in all segments of the gastrointestinal tract and comes with new needs for differentiated preparation regimens. Although the literature is steadily increasing, the results of the conducted trials on preparation are sometimes conflicting. The ingestion of simethicone before gastric and small bowel capsule endoscopy for prevention of air bubbles is established. The value of a lavage before small bowel capsule endoscopy (SBCE) is recommended, although not supported by all studies. Ingestion in the morning before the procedure seems useful for the improvement of mucosa visualization. Lavage after swallowing of the capsule seems to improve image quality, and in some studies also diagnostic yield. Prokinetics has been used with first generation capsules to shorten gastric transit time and increase the rate of complete small bowel visualization. With the massively prolonged battery capacity of the new generation small bowel capsules, prokinetics are only necessary in significantly delayed gastric emptying as documented by a real-time viewer. Lavage is crucial for an effective colon capsule or pan-intestinal capsule endoscopy. Mainly high or low volume polyethylene glycol (PEG) is used. Apart from achieving optimal cleanliness, propulsion of the capsule by ingested boosts is required to obtain a complete passage through the colon within the battery lifetime. Boosts with low volume sodium picosulfate (NaP) or diatrizoate (gastrografin) seem most effective, but potentially have more side effects than PEG. Future research is needed for more patient friendly but effective preparations, especially for colon capsule and pan-intestinal capsule endoscopy.

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.

Examination of Entire Gastrointestinal Tract: A Perspective of Mouth to Anus (M2A) Capsule Endoscopy

Capsule endoscopy (CE) is the only non-invasive diagnostic tool that enables the direct visualization of the gastrointestinal (GI) tract. Even though CE was initially developed for small-bowel investigation, its clinical application is expanding, and technological advances continue. The final iteration of CE will be a mouth to anus (M2A) capsule that investigates the entire GI tract by the ingestion of a single capsule. This narrative review describes the current developmental status of CE and discusses the possibility of realizing an M2A capsule and what needs to be overcome in the future.

Current status of colon capsule endoscopy

While both the annual incidence and mortality of colorectal cancer are slowly but steadily decreasing in the United States, the incidence of such malignancy is increasing in Japan. Thus, controlling colorectal cancer in Japan is a major concern. In 2006, colon capsule endoscopy was first introduced by Eliakim et al. First-generation colon capsule endoscopy had a moderate sensitivity for detecting polyps of more than 6 mm. Thus, second-generation colon capsule endoscopy was developed to achieve higher sensitivity. Colonoscopy is the gold standard tool for colorectal cancer surveillance. With an improvement in the imaging function, the performance of second-generation colon capsule endoscopy is almost as satisfactory as that of colonoscopy. Certain situations, such as incomplete colonoscopy and contraindication for use of sedation, can benefit from colon capsule endoscopy. Colon capsule endoscopy requires a more extensive bowel preparation than colonoscopy and computed tomography colonography because it requires laxatives not only for bowel cleansing but also for promoting the excretion of the capsule. Another problem with colon capsule endoscopy includes the burden of reading and interpretation and overlook of the lesions. Currently, the development of automatic diagnosis of colon capsule endoscopy using artificial intelligence is still under progress. Although the available guidelines do not support the use of colon capsule endoscopy for inflammatory bowel disease, the possible application of colon capsule endoscopy is ulcerative colitis. This review article summarizes and focuses on the current status of colon capsule endoscopy for colorectal cancer screening and the possibility for its applicability on inflammatory bowel disease.

Colon Capsule CLEansing Assessment and Report (CC-CLEAR): a new approach for evaluation of the quality of bowel preparation in capsule colonoscopy

BACKGROUND AND AIMS

Current colon capsule (CC) cleansing grading scales rely on subjective parameters and lack proper interobserver agreement. We should strive for higher intra- and interobserver agreement for the evaluation of the cleansing quality of CCs. Here we sought to validate a new grading scale for the evaluation of CC cleansing.

METHODS

For the new grading scale, named Colon Capsule CLEansing Assessment and Report (CC-CLEAR), the colon was divided in 3 segments: right-sided, transverse, and left-sided colon. Each segment was scored according to an estimation of the percentage of visualized mucosa (0, <50%; 1, 50%-75%; 2, >75%; 3, >90%). The overall cleansing classification was a sum of each segment score, grading between excellent (8-9), good (6-7), and inadequate (0-5). Any segment scoring ≤1 resulted in inadequate overall classification. Videos were reviewed and scored using CC-CLEAR and the Leighton-Rex grading scale by 2 experienced operators blinded to each other. Kendall's coefficient evaluated inter- and intraobserver agreement.

RESULTS

We included 58 consecutive CCs, corresponding to 75.9% women, with a mean age of 65 years. Overall cleansing CC-CLEAR classifications were as follows: reader A, 22.4% (n = 13) excellent, 31% (n = 18) good, and 46.5% (n = 27) inadequate; and reader B, 24.1% (n = 14) excellent, 22.4% (n = 13) good, and 53.4% (n = 31) inadequate. CC-CLEAR interobserver agreement was superior to the Leighton-Rex scale (Kendall's W .911 vs .806, respectively; P < .01). The intraobserver agreement for CC-CLEAR was excellent for both readers (P > .01).

CONCLUSIONS

CC-CLEAR is a new practical and reliable grading scale for the evaluation of bowel preparation quality using a CC, with excellent inter- and intraobserver agreement.

Colon capsule endoscopy

There are multiple indications for luminal imaging of the colon. From assessment of known disease, to diagnosing new pathology; intra-luminal visualisation is the mainstay of gastrointestinal diagnosis. Colonoscopy and radiological imaging are currently the most frequently deployed diagnostic methods. However, both have an associated risk profile, have significant resource pressures and are not universally tolerated. Colon capsule endoscopy (CCE) offers an adjunct to these diagnostic options. In this narrative review the utility of CCE is described. Its current uses, potential benefits and future developments are also discussed.