Meta-Analysis
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Meta-Anal. Mar 31, 2019; 7(3): 110-119
Published online Mar 31, 2019. doi: 10.13105/wjma.v7.i3.110
Higher dose of simethicone decreases colonic bubbles and increases prep tolerance and quality of bowel prep: Meta-analysis of randomized controlled trials
Mohammad F Madhoun, Maham Hayat, Ijlal Akbar Ali
Mohammad F Madhoun, Maham Hayat, Ijlal Akbar Ali, Division of Digestive Diseases and Nutrition, University of Oklahoma Health Sciences Center, Oklahoma, OK 73105, United States
Mohammad F Madhoun, Maham Hayat, Ijlal Akbar Ali, Veteran Affairs Medical Center, Oklahoma, OK 73105, United States
Author contributions: Madhoun MF acquisition of data, analysis and interpretation of data, drafting the article, final approval; Hayat M acquisition of data, analysis and interpretation of data, drafting the article, final approval; Ali IA interpretation of data, revising the article, final approval.
Conflict-of-interest statement: The authors deny any conflict of interest.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Mohammad F Madhoun, MD, MSc, Academic Fellow, Associate Professor, Doctor, Division of Digestive Diseases and Nutrition, University of Oklahoma Health Sciences Center, Andrews Academic Tower, Suite 7426, 800 Stanton L. Young Blvd, Oklahoma, OK 73104, United States. mohammad-madhoun@ouhsc.edu
Telephone: +1-405-2715428
Received: February 22, 2019
Peer-review started: February 22, 2019
First decision: March 5, 2019
Revised: March 21, 2019
Accepted: March 24, 2019
Article in press: March 25, 2019
Published online: March 31, 2019
Processing time: 37 Days and 10.5 Hours
Abstract
BACKGROUND

Antifoaming agents, such as simethicone, may facilitate mucosal inspection during colonoscopy. However, conflicting results have been reported with regard to the impact of simethicone on quality of bowel preparation and adenoma detection rate (ADR).

AIM

To perform a meta-analysis of trials that have compared simethicone vs placebo during colonoscopy.

METHODS

A reproducible literature search of multiple medical databases yielded eleven studies (n = 2605) for inclusion. Studies were compared for quality of bowel preparation, bubbles quality, ADR, and tolerability. Two reviewers independently scored the identified studies for methodology and abstracted pertinent data. Pooling was conducted by both fixed-effects and random-effects models. Relative risk (RR) estimates with a 95% confidence interval (CI) were calculated. Heterogeneity was assessed by I-squared index (I2) statistics.

RESULTS

Patients’ demographic characteristics were comparable in all studies. Of the 2605 patients, 1300 were in the simethicone group, whereas 1305 were in the placebo group. Inadequate bowel preparation was much lower in the simethicone group than in the placebo group [13% vs 24.6%; RR = 0.51 (0.31-0.82); P < 0.0001]. The placebo group was more likely to have significant colonic bubbles than was the simethicone group [35% vs 8%; RR = 1.49 (1.25-1.76); P = 0.0001]. Use of simethicone resulted in a slight, statistically significant increase in ADR compared with the placebo group [26.6% vs 21.6%, RR = 1.07 (1.01-1.13); P = 0.02]. Higher doses of simethicone (> 478 mg) were more likely to result in significant reduction of inadequate bowel preparation, colonic bubbles, and to improve ADR.

CONCLUSION

Adding simethicone improved the quality of bowel preparation, visualization, tolerability, and, eventually, ADR.

Keywords: Simethicone; Colonoscopy; Bubbles; Bowel preparation; Adenoma detection rate

Core tip: Colonoscopy is an essential tool in the screening for and preventing colon cancer, but inadequate colon preparation limits visualization, prolongs procedure time, and, affects exam quality. An antifoaming agent, simethicone, has been a promising addition to bowel preparation. This meta-analysis of randomized controlled trials assessed the effect of its addition to commonly utilized bowel preparations and analyzed the optimum effective dose. We concluded that the addition of simethicone to bowel preparation significantly reduced inadequate bowel preparation, increased adenoma detection rate and trended to improved tolerability of the prep. Higher doses of simethicone were more likely to achieve those outcomes.