Hu Fulan, Wu Zhiwei, Li Guangxiao, Teng Chong, Liu Yupeng, Wang Fan, Zhao Yashuang, Pang Da
Department of Epidemiology, Public Health College, Harbin Medical University, 157 Baojian Street, Nangang District, Harbin, 150081, People's Republic of China.
J Cancer Res Clin Oncol. 2015 Apr;141(4):601-14. doi: 10.1007/s00432-014-1852-7. Epub 2014 Oct 15.
Plasma antioxidants are supposed to be directly related to breast cancer risk. However, the results remain inconsistent. Herein, we carried this meta-analysis to comprehensively summarize the associations between plasma retinol, vitamins A, C and α-tocopherol and breast cancer risk.
We searched PubMed, Embase and the Cochrane Databases (through September 24, 2014) and the reference lists of the retrieved articles in English with sufficient information to estimate relative risk or odds ratio and the 95% confidence intervals (CIs), or with mean serum/plasma level of vitamins and SD/SEM/p value in breast cancer and controls. Two reviewers independently extracted data using a standardized form, with any discrepancy adjudicated by the third reviewer.
Forty studies entered this meta-analysis. For the pooled OR, no significant association between plasma retinol and breast cancer was observed (p = 0.13). Significant association was observed between plasma α-tocopherol and breast cancer (pooled OR 0.42, 95% CI 0.25, 0.72, p = 0.00) in the subgroup with the median lowest level of 5.74-9.16 μmol/L. For the weighted mean difference (WMD), the plasma α-tocopherol and vitamin C level between breast cancer and controls were significantly different [WMD = -0.93 μmol/L (95% CI -1.26, -0.61, p = 0.00) and -2.51 μmol/L (95% CI -4.00, -1.02, p = 0.00), respectively]. No significant association between plasma retinol and vitamin A and breast cancer was observed.
Severe α-tocopherol deficiency could increase breast cancer risk. The association between plasma vitamin C and breast cancer was only significant in case-control studies. There was no significant association between other vitamins and breast cancer risk.
血浆抗氧化剂被认为与乳腺癌风险直接相关。然而，结果仍不一致。在此，我们进行了这项荟萃分析，以全面总结血浆视黄醇、维生素A、C和α-生育酚与乳腺癌风险之间的关联。
我们检索了PubMed、Embase和Cochrane数据库（截至2014年9月24日）以及检索到的英文文章的参考文献列表，这些文章包含足够信息以估计相对风险或比值比及95%置信区间（CIs），或包含乳腺癌患者与对照组中维生素的平均血清/血浆水平及标准差/标准误/p值。两名审阅者使用标准化表格独立提取数据，如有任何差异由第三名审阅者裁决。
40项研究纳入了这项荟萃分析。对于合并的比值比，未观察到血浆视黄醇与乳腺癌之间存在显著关联（p = 0.13）。在最低中位数水平为5.74 - 9.16 μmol/L的亚组中，观察到血浆α-生育酚与乳腺癌之间存在显著关联（合并比值比0.42，95%置信区间0.25, 0.72，p = 0.00）。对于加权平均差（WMD），乳腺癌患者与对照组之间的血浆α-生育酚和维生素C水平存在显著差异[分别为WMD = -0.93 μmol/L（95%置信区间 -1.26, -0.61，p = 0.00）和 -2.51 μmol/L（95%置信区间 -4.00, -1.02，p = 0.00）]。未观察到血浆视黄醇和维生素A与乳腺癌之间存在显著关联。
严重的α-生育酚缺乏可能会增加乳腺癌风险。血浆维生素C与乳腺癌之间的关联仅在病例对照研究中显著。其他维生素与乳腺癌风险之间未观察到显著关联。
