Department of Colorectal Surgery, Changhai Hospital of Second Military Medical University, Shanghai, China.
Eur J Cancer Prev. 2013 Nov;22(6):529-39. doi: 10.1097/CEJ.0b013e328364f1eb.
To comprehensively summarize the association between dietary intake of vitamins A, C, and E and the risk of colorectal adenoma (CRA), the precursor of colorectal cancer, relevant studies were identified in MEDLINE and EMBASE up to 31 October 2012. Summary relative risks (SRRs) with 95% confidence intervals (CIs) were pooled with a random-effects model. Between-study heterogeneity was assessed using Cochran's Q and I statistics. A total of 13 studies with 3832 CRA cases were included in this meta-analysis. On the basis of the highest versus lowest analysis, dietary intake of vitamin C reduced the risk of CRA by 22% (SRRs 0.78, 95% CIs: 0.62-0.98). Subgroup analyses showed that this relation was not modified by BMI, smoking status, and dietary energy intake. Further, dietary intake of β-carotene was also inversely associated with the risk of CRA. However, dietary intake of vitamins A and E was not associated with the risk of CRA in overall and subgroup analyses (vitamin A: SRRs 0.87, 95% CIs: 0.67-1.14; vitamin E: SRRs 0.87, 95% CIs: 0.69-1.10). Our results indicate that dietary intake of vitamin C and β-carotene, but not vitamins A and E, could reduce the risk of CRA. However, these associations seem to be limited. Further investigation using large samples and a rigorous methodology is warranted.
为了全面总结维生素 A、C 和 E 的饮食摄入与结直肠腺瘤（CRA）风险之间的关联，CRA 是结直肠癌的前期病变，我们在 MEDLINE 和 EMBASE 中检索了截至 2012 年 10 月 31 日的相关研究。采用随机效应模型汇总具有 95%置信区间（CI）的汇总相对风险（SRR）。采用 Cochran's Q 和 I 统计量评估研究间的异质性。本荟萃分析共纳入了 13 项研究，包含 3832 例 CRA 病例。基于最高与最低分析，维生素 C 的饮食摄入降低了 22%的 CRA 风险（SRR 0.78，95%CI：0.62-0.98）。亚组分析表明，这种关系不受 BMI、吸烟状况和饮食能量摄入的影响。此外，β-胡萝卜素的饮食摄入也与 CRA 的风险呈负相关。然而，维生素 A 和 E 的饮食摄入与 CRA 的风险在总体和亚组分析中均无相关性（维生素 A：SRR 0.87，95%CI：0.67-1.14；维生素 E：SRR 0.87，95%CI：0.69-1.10）。我们的结果表明，维生素 C 和β-胡萝卜素的饮食摄入可能降低 CRA 的风险，而维生素 A 和 E 的饮食摄入则不然。然而，这些关联似乎是有限的。需要进一步采用大样本和严格的方法进行研究。
