Randomized, controlled trial of 2 L polyethylene glycol plus ascorbate components versus sodium phosphate for bowel cleansing prior to colonoscopy for cancer screening.
BACKGROUND
Colonoscopy requires effective bowel preparation for adequate mucosal visualization. Safety and acceptability of bowel preparation are key components in colorectal cancer screening (CRC) populations.


OBJECTIVE
To compare the efficacy, safety and acceptability of bowel preparation with polyethylene glycol (PEG), ascorbic acid, sodium ascorbate (ascorbate components), sodium sulfate and electrolytes (PEG+Asc) or sodium phosphate (NaP).


METHODS
Consenting adults undergoing elective out-patient colonoscopy for CRC were randomized to take 2 L PEG+Asc or 90 mL NaP (control) following manufacturer's instructions. PEG+Asc was taken the evening before and morning of the colonoscopy; NaP was taken the morning and evening before colonoscopy. Participants followed a restricted diet specific to each preparation. Primary endpoint was bowel cleansing success (100% colon mucosa visible) rated by an independent expert panel (all experienced endoscopists) unaware of treatment allocations. Subject reported outcomes about the preparations were elicited. Adverse events were recorded.


CLINICAL TRIAL REGISTRATION
Clinicaltrials.gov: NCT00427089.


RESULTS
Successful bowel cleansing rate was significantly higher in the PEG+Asc (N = 242) than the NaP (N = 114) group (PEG+Asc 93.4% [95% CI 89.5-96.2] versus NaP 22.8% [15.5-31.6%], p < 0.0001). Subject reported outcomes on acceptability of the two different preparations were not significantly different (p = 0.238). However, taste ratings for PEG+Asc were significantly better versus NaP (mean VAS: 31.2 and 38.1 respectively, p = 0.0111). The proportion of patients prepared to receive the same preparation again was significantly higher in the PEG+Asc group (88.4% vs. 78.1%, p < 0.0001).


CONCLUSIONS
PEG+Asc provided superior bowel cleansing to NaP and was well tolerated. Findings for PEG+Asc are aligned with previous similar studies; however, differences observed in NaP cleansing results, especially for the proximal colon segments, may be due to factors including: differences in demographics and population types and the use of the validated Harefield Cleansing Scale as an assessment tool combined with expert reviews, which may have resulted in conservative cleansing assessments.
['Ell|C|C|', 'Fischbach|W|W|', 'Layer|P|P|', 'Halphen|M|M|']
D000293:Adolescent D000328:Adult D000368:Aged D000369:Aged, 80 and over D000553:Ambulatory Care D002400:Cathartics D003113:Colonoscopy D015179:Colorectal Neoplasms D005260:Female D006801:Humans D008297:Male D008875:Middle Aged D017060:Patient Satisfaction D010710:Phosphates D011092:Polyethylene Glycols D011300:Preoperative Care D055815:Young Adult
Polyethylene glycol Ascorbate components Sodium phosphate Colonoscopy Ascorbic acid Sodium ascorbate Colon cancer screening