补充叶酸对溃疡性结肠炎相关结直肠癌和非典型性增生发病风险影响的Meta分析

Effect of Folic Acid Supplementation on the Risk of Cancer and Atypical Dysplasia in Ulcerative Colitis: A Meta-analysis

目的评价补充叶酸对溃疡性结肠炎(UC)相关结直肠癌和非典型性增生发病风险的影响。方法计算机检索Cochrane图书馆、PubMed、EMBase、ISI数据库、中国期刊全文数据库、中文科技期刊数据库和万方数据库,检索时间从建库至2012年12月;同时手工检索相关文献的参考文献及国内外重要胃肠病会议摘要。筛选补充叶酸与UC相关结直肠癌和非典型性增生关系相关的研究,由2名研究者独立进行资料提取与文献质量评价。应用RevMan 5.2统计软件进行Meta分析,合并效应量为比值比(OR)。结果最终共纳入4个符合标准的研究,其中发生UC相关结直肠癌和非典型性增生88例(病例组),未发生UC相关结直肠癌和非典型性增生223例(对照组)。病例组补充叶酸者20例,对照组补充叶酸者94例,Meta分析结果显示,补充叶酸者UC相关结直肠癌和非典型性增生发生率低于未补充叶酸者〔OR=0.40,95%CI(0.22,0.70),P=0.002〕。结论补充叶酸有助于降低UC相关结直肠癌和非典型性增生发生率。

Objective To evaluate the influence of folic acid supplementation on the ulcerative colitis（UC）-associated colorectal cancer and atypical dysplasia.Methods Computer-assisted searches of the Cochrane Database,PubMed,EMBase,ISI Database,Full-text Database of Chinese Journals,Chinese Sci-tech Journal Database,and Wanfang database from the inception of each database to December 2012 were used to identify all available studies.Meanwhile,manual searches of literature references and abstracts of the important domestic or international gastroenterology meetings were utilized to obtain relevant studies.Articles involving effects of folic acid supplementation on the risk of UC-associated colorectal cancer and dysplasia were screened by two independent reviewers.The data extraction and quality assessment were implemented independently.The meta-analysis was performed by using Review Manager 5.2 software,with calculation of the odds ratio（OR） and its 95% confidence interval（CI）.Results Four studies involving 88 cases of UC-associated colorectal cancer or dysplasia and 223 controls were included in the study.Twenty cases in the case group and 94 cases in the control group had folic acid supplementation.Meta-analysis showed that the incidence of UC-associated colorectal cancer and dysplasia was lower in cases with folic acid supplementation than in those without 〔OR = 0.40,95% CI（0.22,0.70）,P = 0.002〕.Conclusion Folic acid supplementation can reduce the incidence of UC-associated colorectal cancer and dysplasia.