Division of Gastroenterology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Clin Gastroenterol Hepatol. 2012 Nov;10(11):1225-31. doi: 10.1016/j.cgh.2012.08.029. Epub 2012 Aug 30.
BACKGROUND & AIMS: Adequate bowel cleansing is an important determinant of the efficacy of screening colonoscopy. Polyethylene glycol (PEG)-based solutions are used commonly in bowel preparation, but their poor palatability and large volumes (4 L) influence compliance. Adjunct therapies, such as bisacodyl, split-dose regimens, and lower-volume regimens have been tested. We performed a meta-analysis to determine whether a 4-L split dose of PEG is better than others for bowel cleansing before colonoscopy.
We searched MEDLINE, the Cochrane Central Register of Controlled Trials and Database, recent abstracts from major conference proceedings, references from selected reviews and randomized trials (http://clinicaltrials.gov), and Google Scholar, through September 2011, for high-quality, randomized trials that compared 4-L split-dose PEG without adjunct therapy with other bowel preparation methods. Nine of 2477 trials considered were used in the analysis. We calculated pooled estimates of bowel preparation quality (primary outcome: excellent or good), preparation compliance, favorable overall experiences, willingness to repeat same preparation, and side effects. We calculated pooled estimates of odds ratios by fixed- and random-effects models. We also assessed heterogeneity among studies and publication bias.
The overall pooled odds ratio for excellent or good bowel preparation quality for 4-L split-dose PEG was 3.46, compared with other methods (95% confidence interval, 2.45-4.89; P < .01). Although there was significant heterogeneity in results among studies, 7 of 9 reported a significant benefit from the 4-L split-dose PEG preparation. There were no significant differences between PEG and others in preparation compliance, favorable overall experience, willingness to repeat the same preparation, abdominal cramping, nausea, or sleep disturbance. There was no significant publication bias based on funnel plot.
A meta-analysis showed that 4-L split-dose PEG is better than other bowel preparation methods for colonoscopy. Significant heterogeneity among studies might result from differences in patient demographics and protocols. A 4-L split dose of PEG should be considered the standard with which new bowel preparation methods are compared.
充分的肠道清洁是筛查结肠镜检查效果的一个重要决定因素。聚乙二醇（PEG）基溶液常用于肠道准备，但因其较差的口感和较大的体积（4 升）影响了患者的依从性。已尝试了辅助治疗，如比沙可啶、分剂量方案和低容量方案。我们进行了一项荟萃分析，以确定在结肠镜检查前，4 升分剂量 PEG 是否优于其他肠道清洁方法。
我们检索了 MEDLINE、Cochrane 对照试验中心注册库和数据库、主要会议论文集的最新摘要、选定综述和随机试验的参考文献（http://clinicaltrials.gov）以及 Google Scholar，检索时间截至 2011 年 9 月，以寻找比较 4 升分剂量 PEG 无辅助治疗与其他肠道准备方法的高质量随机试验。在考虑的 2477 项试验中，有 9 项试验用于分析。我们计算了肠道准备质量（主要结局：优秀或良好）、准备依从性、总体体验良好、愿意重复相同准备、不良反应的合并估计值。我们使用固定效应和随机效应模型计算了合并比值比的估计值。我们还评估了研究间的异质性和发表偏倚。
与其他方法相比，4 升分剂量 PEG 用于肠道准备的优秀或良好质量的总体合并比值比为 3.46（95%置信区间，2.45-4.89；P <.01）。尽管研究结果存在显著的异质性，但 9 项研究中有 7 项报告了 4 升分剂量 PEG 准备的显著获益。PEG 与其他方法在准备依从性、总体体验良好、愿意重复相同准备、腹部痉挛、恶心或睡眠障碍方面无显著差异。基于漏斗图，未发现显著的发表偏倚。
一项荟萃分析表明，4 升分剂量 PEG 比其他肠道准备方法更适合结肠镜检查。研究间的显著异质性可能是由于患者人群和方案的不同所致。4 升分剂量 PEG 应被视为与新肠道准备方法比较的标准。
