A lower volume of polyethylene glycol with ascorbate (MoviPrep) may improve bowel cleansing prior to colonoscopy

1. 1 litre polyethylene glycol with ascorbate (1L-PEG-Asc) showed superior bowel cleansing efficacy compared to 2 litre polyethylene glycol with ascorbate (2L-PEG-Asc) in adult patients undergoing colonoscopy for colorectal cancer (CRC) screening.

Evidence Rating Level: 1 (Excellent)

Colonoscopy is a highly effective procedure for CRC screening and has been shown to reduce CRC mortality. High-quality preoperative bowel cleansing is associated with higher polyp detection and cecal intubation rates. Inadequate bowel cleansing also increases the risk of procedural difficulties and is associated with increased risk of post-colonoscopy colorectal cancer deaths. There are numerous types of bowel preparation, with higher volume solutions resulting in nausea, vomiting, bloating, and abdominal distention. It is thought these side effects can lead to reduced adherence and subsequent inferior cleansing. Previous trials have shown 1L-PEG-Asc to be non-inferior to (2L-PEG-Asc), Moviprep®. However, no studies have assessed whether 1L-PEG-Asc is superior. This randomized, single-centre, superiority trial included patients aged 50-74 years with a positive fecal immunochemical test (FIT) test scheduled for screening colonoscopy. 1275 patients were randomized to receive 1L-PEG-Asc (n = 615; mean [SD] age, 63.0 [8] years; 50.9% female) or 2L-PEG-Asc (n = 628; mean [SD] age, 62.9 [8] years; 47.8% female). Mean Boston Bowel Preparation Scale (BBPS) scores were significantly higher in the 1L-PEG-Asc group compared to the 2L-PEG-Asc group (right 2.54 vs. 2.30, p <0.001; transverse 2.60 vs. 2.36, p <0.001; left 2.63 vs. 2.39, p <0.001). The 1L-PEG-Asc group had higher rates of adequate preparation (BPPS ≥ 2 in each segment; 92.2% vs 86.1%, p<0.001) and excellent preparation (BPPS = 3 in each segment; 59.2% vs 43.8%, p<0.001). There were no significant differences in lesion detection rates. Nausea (57.4% vs. 46.6%, p<0.001) and vomiting (13.9% vs. 8.7%, p=0.006) were more frequent in the 1L-PEG-Asc group. However, a significantly greater proportion of patients were willing to repeat bowel preparation with 1L-PEG-Asc compared to 2L-PEG-Asc (82% vs. 76%, p=0.009). Overall, 1L-PEG-Asc showed greater bowel cleansing efficacy and willingness to use it again despite greater rates of side effects.

Click here to read the study in BMC Gastroenterology

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