Su1684 A Randomized Controlled Trial Comparing a Prepackaged Low-Residue Diet Versus a Restricted Diet for Colonoscopy Preparation

patients with previous colorectal resection, mainly for those with left colectomy. Our study is the first trial comparing two different preparations in this group of patients; therefore, larger, multicentre, randomized studies are warranted to confirm our findings. Su1684 A Randomized Controlled Trial Comparing a Prepackaged LowResidue Diet Versus a Restricted Diet for Colonoscopy Preparation Tomoaki Matsumura*, Makoto Arai, Kenichiro Okimoto, Daisuke Maruoka, Shoko Minemura, Hideaki Ishigami, Tomoo Nakagawa, Osamu Yokosuka Department of Gastroenterology and Nephrology, Chiba university, Chiba, Japan Background and Aim: An Adequate bowel preparation is essential to properly visualize the colon mucosa during a colonoscopy. Therefore, a clear liquid diet is widely used for colonoscopy preparation on the day before the procedure. However, this dietary modification may be poorly tolerated. There were some previous studies for colon cleansing comparing the clear liquids diet to a low-residue diet, but the efficacy for colonoscopy preparation by a prepackaged low-residue diet compared to a restricted diet was not investigated. The aim of this study was to investigate the clinical utility of the prepackaged low-residue diet compared to the restricted diet. Material and Methods: This is a prospective randomized controlled trial of patients undergoing screening or surveillance colonoscopy. A total 100 patients were randomly assigned for this study, 50 in each group. After exclusions, 45 patients in the prepackaged 2 meal products (a lunch and dinner) low-residue diet (PLD) group and 46 in the restricted diet (RD) group were analyzed. In the RD group, the patients was given an information sheet containing acceptable low-residue options and coached by the medical staff. All patients received a sodium picosulfate the day before colonoscopy and low-volume bowel preparation (1L PEG solution + ascorbic acid: MoviPrep ) on the day of colonoscopy. If the colon cleansing was not achieved enough, additional PEG solution was given to the patients and its amount was measured. The primary outcome was efficacy of colon cleansing, rated by the modified Boston Bowel Preparation Scale (m-BBPS: 0Z inadequate, 18Z excellent). An additional amount of PEG solution, and adenoma detection rate were assessed as secondary outcomes. This study was registered at the University Hospital Medical Information Network (UMIN000011979). Results: The m-BBPS score in the PLD group was 14.6 3.2, compared with 12.9 3.5 in the RD group. Bowel preparation quality was significantly higher in the PLD group (P! 0.05). The mean amount of additional PEG solution in the PLD group was smaller than the RD group (293.8 474.8 vs. 444.1 625.0 mL). However there was no statistical difference between the two groups. Adenoma detection rates were similar in the two groups (73.3% vs. 71.7%). Conclusion: A prepackaged 2 meal products low-residue diet is superior to a restricted diet for colonoscopy preparation.