Effect Of Prepackaged Clear Liquid Diet On Intestinal Preparation Quality In High Risk Population

Objective Colonoscopy is the most commonly used and important screening procedure for intestinal diseases.However,the accuracy of colonoscopy is closely related to the quality of preoperative intestinal preparation.Multiple studies have shown that inadequate bowel preparation significantly reduces the detection rate of colorectal tumors.Therefore,clear vision is very important to reduce the rate of missed diagnosis.At present,the most commonly used method is to restrict diet 24 hours before surgery,eat a low-residue diet that is easy to digest,and take 4L compound polyethylene glycol electrolyte powder(PEG)before surgery to clean the intestine.This method can usually achieve a good intestinal preparation for the general population,but for high-risk patients of intestinal preparation,the quality of bowel preparation was poor,such as in people with chronic constipation,advanced age,obesity,a history of colon surgery,a history of other medical conditions(such as diabetes,Parkinson’s disease,stroke,or spinal cord injury),and the use of tricyclic antidepressants or anesthetics.The purpose of this study was to investigate whether pre-packaged clear liquid diet can assist to improve the quality of intestinal preparation in people who are in a high risk of having an inadequate intestinal preparation,and to verify its effectiveness and safety.Methods This is a prospective,two-center,single-blind,randomized controlled trial(RCT).A total of 151 patients who admitted to the Shandong Provincial Hospital and Binzhou People’s Hospital from November 2021 to December 2022 met the inclusion and exclusion criteria for colonoscopy.They were randomly divided into two groups according to the table of random digit:Group A(77 patients):Self-prepared low-residue diet for 2 days;Group B(74 patients):1 day low-residue diet and 1 day prepackaged clear liquid diet.Specific program:Diet restriction:the control group began to eat self-prepared low-residue diet 2 days before colonoscopy,avoid eating solid foods,indigestible high-fiber foods(meat,fruits,vegetables etc.).The meal replacement group was given a self-prepared low-residue diet on the penultimate day before colonoscopy and a prepackaged clear liquid diet(meal replacement)on the day before colonoscopy.Laxative usage:4L polyethylene glycol(PEG)was taken in divided doses before colonoscopy,that is,2L PEG solution was taken one night before the examination,and 2L PEG solution was taken 4 to 6 hours before the examination.The main outcome measures were intestinal preparation quality,which was described quantitatively by Boston Bowel Preparation Scale(BBPS),and the secondary outcome measures were the duration of endoscopy entry and exit,the number of adenoma detection rate(ADR)and polyp detection rate(PDR),the frequency and total times of satisfactory defecation,whether there were serious adverse reactions,and the willingness of patients to repeat.Results A total of 151 patients who came to our hospital for colonoscopy were included in this study.Finally,77 cases of group A(self-prepared low-residue diet group)and 74 cases of group B(pre-packaged transparent liquid diet group)were included in the following analysis.There was no statistical difference in baseline data between the two groups.Main evaluation measures:Boston score(BBPS):qualification rate of intestinal preparation(BBPS≥6)in group B was higher than that in group A(89.19%vs.76.62%,p=0.041),there was no statistical difference between two groups in segmented colons(p>0.05).The mean(SD)BBPS of group B was higher than that of group A(7.32±1.05 vs 6.78±1.45,p=0.009),and BBPS scores of group B were higher than that of group A for segmented colons(p<0.05).There was no significant difference in the duration of endoscopy entry and exit,ADR and PDR between the two groups(p>0.05).The frequency and total times of satisfactory defecation of two groups had no statistical difference(p>0.05).Patient tolerance:There was no significant statistical difference in the incidence of adverse reactions between the two groups(p>0.05),and the willingness to repeat in both groups reached more than 90%,with no statistically significant difference(96.10%vs.94.59%,p=0.957).In subgroup analysis,only the constipated and not obese group had higher mean(SD)BBPS score in group B than in group A(7.24±1.13 vs 6.32±1.82,p=0.038).Conclusion For people at high risk of inadequate intestinal preparation,using pre-packaged clear liquid diet one day before colonoscopy can obtain higher quality intestinal preparation than traditional self-prepared low-residue diet,without increasing the detection rate of polyps and adenomas,without increasing the incidence of adverse reactions,and also achieve a higher level of tolerance,which is a safe and effective intestinal preparation program.This regimen has higher effectiveness for constipated patients without obesity.