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Type 2 diabetes mellitus and risk of colorectal adenoma: a meta-analysis of observational studies

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      Abstract

      BackgroundTo summarize the relationship between type 2 diabetes mellitus (T2DM) and risk of colorectal adenomas (CRA), we performed a meta-analysis of observational studies.MethodsTo find studies, we searched PubMed, Embase, the Cochrane Library, Web of Science and conference abstracts and related publications for American Society of Clinical Oncology and the European Society of Medical Oncology. Studies that reported relative risks (RRs) or odds ratios (ORs) with 95 % confidence intervals (CIs) for the association between T2DM and risk of CRA were included. The meta-analysis assessed the relationships between T2DM and risk of CRA. Sensitivity analyses were performed in two ways: (1) by omitting each study iteratively and (2) by keeping high-quality studies only. Publication bias was detected by Egger’s and Begg’s tests and corrected using the trim and fill method.ResultsThis meta-analysis included 17 studies with 28,999 participants and 6798 CRA cases. We found that T2DM was a risk factor for CRA (RR: 1.52; 95 % CI: 1.29–1.80), and also for the advanced adenoma (RR: 1.41; 95 % CI: 1.06–1.87). Patients with existing T2DM (RR: 1.56; 95 % CI: 1.16–2.08) or newly diagnosed T2DM (RR: 1.51; 95 % CI: 1.16–1.97) have a risk of CRA. Similar significant results were found in retrospective studies (RR: 1.57; 95 % CI: 1.30–1.89) and population based cross-sectional studies (RR: 1.46; 95 % CI: 1.21–1.89), but not in prospective studies (RR: 1.27; 95 % CI: 0.77–2.10).ConclusionsOur results suggested that T2DM plays a risk role in the risk of developing CRA. Consequently, medical workers should increase the rate of CRA screening for T2DM patients so that they can benefit from behavioural interventions that can help prevent the development of colorectal cancer. Additional, large prospective cohort studies are needed to make a more convincing case for these associations.Electronic supplementary materialThe online version of this article (doi:10.1186/s12885-016-2685-3) contains supplementary material, which is available to authorized users.

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            Author and article information

            Affiliations
            [1 ]Medical Service Research Division, Navy Medical Research Institute, Shanghai, China
            [2 ]Department of Health Statistics, Second Military Medical University, No. 800 Xiangyin Road, Shanghai, 200433 China
            [3 ]Department of Colorectal Surgery, Changhai Hospital, Shanghai, China
            [4 ]College of Art & Science, University of San Francisco, San Francisco, USA
            Contributors
            +86-21-81871441 , hejia63@yeah.net
            Journal
            BMC Cancer
            BMC Cancer
            BMC Cancer
            BioMed Central (London )
            1471-2407
            17 August 2016
            17 August 2016
            2016
            : 16
            27535548
            4989384
            2685
            10.1186/s12885-016-2685-3
            © Yu et al. 2016

            Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License ( http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver ( http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

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            Research Article
            Custom metadata
            © The Author(s) 2016

            Oncology & Radiotherapy

            colorectal adenoma, type 2 diabetes mellitus, meta-analysis

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