The relationship between red meat consumption and colorectal cancer (CRC) has been the subject of scientific debate. To estimate the summary association between red meat intake and CRC and to examine sources of heterogeneity, a meta-analysis of prospective studies was conducted. Thirty-four prospective studies of red meat and CRC were identified, of which 25 represented independent nonoverlapping study populations. Summary relative risk estimates (SRREs) for high versus low intake and dose-response relationships were calculated. In the high versus low intake meta-analysis, the SRRE was 1.12 (95% CI: 1.04-1.21) with significant heterogeneity (P=0.014). Summary associations were modified by tumor site and sex. The SRREs for colon cancer and rectal cancer were 1.11 (95% CI: 1.03-1.19) and 1.19 (95% CI: 0.97-1.46), respectively. The SRREs among men and women were 1.21 (95% CI: 1.04-1.42) and 1.01 (95% CI: 0.87-1.17), respectively. The available epidemiologic data are not sufficient to support an independent and unequivocal positive association between red meat intake and CRC. This conclusion is based on summary associations that are weak in magnitude, heterogeneity across studies, inconsistent patterns of associations across the subgroup analyses, and the likely influence of confounding by other dietary and lifestyle factors.
EpidStat in the News
EpidStat presented "Survival Synthesis: Methods for Meta-analysis of Survival Rates and Aggregation of Survival Data" at a poster session for the International Conference on Health Policy Statistics on January 10, 2018 in Charlston, SC. The poster details the methods used in Bylsma et al. Arteriovenous Fistulae for Haemodialysis: A Systematic Review and Metaanalysis of Efficacy and Safety Outcomes. European Journal of Vascular and Endovascular Surgery, 2017. We discussed the process of digitizing survival curves from the published literature and simulating individual patient data to derive survival statistics that were not published with the article. We conclude that while labor-intensive, the methodology makes the best use of available study data.
EpidStat presented "Prevalence of KRAS and BRAF Mutations in Metastatic Colorectal Cancer (mCRC) by Tumor Location: A Review and Meta-analysis" on January 20, 2018 at the ASCO Gastrointestinal Cancers Symposium. Results from 44 studies comprising nearly 16,000 mCRC patients demonstrated that both KRAS and BRAF mutations were significantly more prevalent among right-sided colon tumors than left-sided tumors. These results may aid clinicians and researchers in the search for target novel therapeutics.