Division of Preventive Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02215, USA.
J Natl Cancer Inst. 2012 Oct 17;104(20):1562-75. doi: 10.1093/jnci/djs370. Epub 2012 Oct 12.
Folic acid, vitamin B(6), and vitamin B(12) act in concert in the one-carbon metabolism and may protect against colorectal neoplasia. We examined the effect of combined B-vitamin treatment on the occurrence of colorectal adenoma.
The Women's Antioxidant and Folic Acid Cardiovascular Study was a randomized, double-blind, placebo-controlled trial of 5442 female health professionals at high risk for cardiovascular disease from April 1998 through July 2005. Participants were randomly assigned to receive a combination pill of folic acid (2.5mg), vitamin B(6) (50mg), and vitamin B(12) (1mg) or placebo. This study included 1470 participants who were followed up for as long as 9.2 years and underwent an endoscopy at any point during follow-up. We estimated relative risks using a generalized linear model with a natural logarithm link function and Poisson distributed errors. All statistical tests were two-sided.
The risk of colorectal adenoma was similar among participants receiving treatment (24.3%, 180 of 741 participants) vs placebo (24.0%, 175 of 729 participants) (multivariable adjusted relative risk = 1.00, 95% confidence interval = 0.83 to 1.20). Treatment was not associated with the risk of adenoma when data were analyzed by subsite, size, stage, and the number of adenomas. There was no statistically significant effect modification by alcohol intake, history of cancer or adenoma, or baseline plasma levels or intakes of folate, vitamin B(6), or vitamin B(12).
Our results indicate no statistically significant effect of combined folic acid, vitamin B(6), and vitamin B(12) treatment on colorectal adenoma among women at high risk for cardiovascular disease.
叶酸、维生素 B(6) 和维生素 B(12) 在一碳代谢中协同作用，可能有助于预防结直肠肿瘤。我们研究了联合 B 族维生素治疗对结直肠腺瘤发生的影响。
女性抗氧化剂和叶酸心血管研究是一项随机、双盲、安慰剂对照试验，纳入了 1998 年 4 月至 2005 年 7 月期间 5442 名患有心血管疾病高危因素的女性健康专业人员。参与者被随机分配接受叶酸（2.5mg）、维生素 B(6)（50mg）和维生素 B(12)（1mg）联合片剂或安慰剂。本研究包括 1470 名参与者，随访时间最长达 9.2 年，在随访期间的任何时候都进行内镜检查。我们使用具有自然对数链接函数和泊松分布误差的广义线性模型来估计相对风险。所有统计检验均为双侧检验。
治疗组（24.3%，741 名参与者中的 180 名）与安慰剂组（24.0%，729 名参与者中的 175 名）结直肠腺瘤的风险相似（多变量调整后的相对风险=1.00，95%置信区间=0.83 至 1.20）。当按亚部位、大小、分期和腺瘤数量分析数据时，治疗与腺瘤风险无关。饮酒量、癌症或腺瘤史、基线血浆水平或叶酸、维生素 B(6)或维生素 B(12)摄入量均无统计学显著的效应修饰作用。
我们的研究结果表明，对于患有心血管疾病高危因素的女性，联合使用叶酸、维生素 B(6)和维生素 B(12)治疗对结直肠腺瘤没有统计学显著的影响。
