Low-volume regimen without additional liquids or adjunctive agents versus standard bowel preparation in non-constipated patients: a propensity score matching analysis

Abstract

Aims

Split-dose, 4-L polyethylene glycol (PEG, HSD) is currently the first-line choice for unselected or difficult colon preparations. Almost all low-volume bowel preparations (BPs) include a large volume of additional liquid and adjunctive agents to improve cleansing efficiency. However, neither HSD nor additional liquids or adjunctive agents of low-volume regimens may be necessary for low-risk patients. The aim of this study was to compare the cleansing efficiency between split-dose, low-volume (2-L) PEG without additional liquids or adjunctive agents (LSD) and HSD in non-constipated patients.

Methods

A retrospective study was performed from January 2013 to December 2015. Consecutive non-constipated patients who received LSD or HSD BPs were enrolled into LSD and HSD groups. Propensity score matching (PSM) was used to reduce selection bias and potential confounders. The primary outcome was bowel cleansing quality, as evaluated by the Boston Bowel Preparation Scale (BBPS). The adenoma detection rate (ADR), the most important secondary outcome, was also recorded. Follow-up was conducted in 2016.

Results

After excluding those participants who meet exclusion criteria or lost follow-up, 1656 non-constipated patients underwent LSD (n = 999) or HSD (n = 657) BP. Most patients had a BBPS score ≥6 (LSD vs. HSD, 93.6 vs. 92.9%, p = .166). The segmental BBPS scores were ≥2 in 92 and 91.9% in the LSD and HSD groups, respectively. The overall ADR was 16.7% in the LSD group and 17.5% in the HSD group (p = .334).

Conclusion

For non-constipated patients, LSD is not inferior to HSD in cleansing efficiency, while more willing to repeat the same BP.

Keywords:

• Additional liquids
• adjunctive agents
• low-volume regimen
• non-constipated patients
• propensity score-matching

Ethical approval

The trial protocol approved by the ethics committee of the hospitals (Zhengzhou Tumor Hospital Affiliated to Henan University and First Affiliated Hospital of Anhui Medical University) were conducted in accordance with the Helsinki Declaration and good clinical practice. It was retrospectively registered on November 7, 2017 (ChiCTR-ORC-17013278).

Disclosure statement

This study was profitless, and the authors were not related to the manufacturers of the colonic cleansing agents used in the study. No potential conflict of interest was reported by the author(s).

Author contributions

Study concept and design: Jianglong Hong; acquisition of data: Renyu Fan, Lei Diao, Xiang Li; analysis and interpretation of data: Chen Shi, Renyu Fan, Weiping Zhang, Xiang Li, Yufang Cui; drafting and editing of the manuscript: Chen Shi, Jianglong Hong, Lei Diao, Xiang Li; critical revision of the manuscript for important intellectual content: Jianglong Hong; statistical analysis: Jianglong Hong, Weiping Zhang, Xiang Li, Yufang Cui.