Efficacy And Safety Of Polyethylene Glycol Compared Split Dose To Single Dose Morning-only For Colonoscopy Preparation:a Meta-analysis

Objective To systematically evaluate the effectiveness and safety of polyethylene glycol(PEG)regimen for bowel preparation to colonoscopy compared split dose(PM/AM)to single dose(AM-only)in the morning.Methods Databases including Cochrane Central Register of Controlled Trials & Database of Systematic Reviews?MEDLINE?CINAHL?EMBASE?Pub Med ? Wan Fang Data and CNKI Data were electronically searched for randomized controlled trials(RCT)about bowel preparation for colonoscopy compared to split-dose PEG to single-dose PEG in the morning.The risk of bias of included RCTs were independently screened literature,extracted data and assessed by two reviewers according to inclusion and exclusion criteria.Then,meta-analysis was conducted by using Stata12.0 software.Results A total of 6 RCTs concerning 1258 cases were included.The result of meta-analysis showed that there were no significant association between split-dose(PM/AM)PEG and single-dose(AM-only)PEG on cleanliness of colon[RR=1.036,95%CI(0.998,1.076),p=0.066],polyps detection rate[RR=0.981,95%CI(0.622,1.546),p=0.934] and adenoma detection rate[RR=0.895,95%CI(0.716,1.119),p=0.680].Also,there were no significant association about vomiting[RR=0.755,95%CI(0.500,1.139),p=0.180],abdominal pain[RR=0.979,95%CI(0.614,1.560),p=0.929],bloating[RR=0.967,95%CI(0.793,1.178),p=0.737],headache[RR=1.245,95%CI(0.862,1.799),p=0.243] and sleep disorder[RR=2.017,95%CI(0.955,4.262),p=0.066] in the two group.But compared with single-dose(AM-only)PEG,the split-dose(PM/AM)PEG can reduce the rate of nausea[RR=0.857,95%CI(0.738,0.994),p=0.042].Conclusions In bowel preparation of colonoscopy,single-dose(AM-only)PEG may not have an advantage over single-dose(AM-only)PEG about effectiveness and reduction of most adverse reactions.But,single-dose(AM-only)PEG may decrease the incidence of nausea compared with single-dose(AM-only)PEG.