Effects of supplemental α-tocopherol and β-carotene on colorectal cancer:: results from a controlled trial (Finland)
Effects of supplemental α-tocopherol and β-carotene on colorectal cancer:: results from a controlled trial (Finland)
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DOI：
10.1023/a:1008936214087
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发表时间：
2000-03-01
影响因子：
2.3
通讯作者：
Heinonen, OP
中科院分区：
文献类型：
--
作者：
Albanes, D;Malila, N;Heinonen, OP
背景资料：一些流行病学调查表明，维生素E和β-胡萝卜素的高摄入量或生化状态可能与结直肠癌的风险降低有关。我们在α-生育酚，β-胡萝卜素癌症预防（ATBC）研究中测试了α-生育酚和β-胡萝卜素补充剂对结直肠癌发病率的影响，这是一项双盲，安慰剂对照试验，133名50-69岁男性吸烟者。参与者被随机分配接受α-生育酚（50毫克），β-胡萝卜素（20毫克），这两种药物，或安慰剂每天5-8年。通过全国癌症登记处确定了结肠直肠癌（n = 135），99%经组织学证实。干预效果进行了评估，使用生存分析和比例风险models.Results：大肠癌的发病率是有点低，α-生育酚组相比，没有α-生育酚组，但这一发现是没有统计学意义（相对危险度（RR）= 0.78，95%置信区间（CI）0.55-1.09;对数秩检验p = 0.15）。β-胡萝卜素对结直肠癌发病率没有影响（RR = 1.05，95%CI 0.75-1.47;对数秩检验p = 0.78）。有两种物质之间没有相互作用。结论：我们的研究发现，没有证据表明β-胡萝卜素在老年男性吸烟者的结直肠癌的有益或有害的影响，但确实提供了提示性的证据，维生素E补充剂可能有适度的预防作用。后一项发现与先前的研究结果雅阁，该研究将较高的维生素E水平与降低结直肠癌风险联系起来。
Background: Some epidemiological investigations suggest that higher intake or biochemical status of vitamin E and beta-carotene might be associated with reduced risk of colorectal cancer.Methods: We tested the effects of alpha-tocopherol and beta-carotene supplementation on the incidence of colorectal cancer in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study, a double-blind, placebo-controlled trial among 29,133 50-69-year-old male cigarette smokers. Participants were randomly assigned to receive alpha-tocopherol (50 mg), beta-carotene (20 mg), both agents, or a placebo daily for 5-8 years. Incident colorectal cancers (n = 135) were identified through the nationwide cancer registry, and 99% were histologically confirmed. Intervention effects were evaluated using survival analysis and proportional hazards models.Results: Colorectal cancer incidence was somewhat lower in the alpha-tocopherol arm compared to the no alpha-tocopherol arm, but this finding was not statistically significant (relative risk (RR) = 0.78, 95% confidence interval (CI) 0.55-1.09; log-rank test p = 0.15). beta-Carotene had no effect on colorectal cancer incidence (RR = 1.05, 95% CI 0.75-1.47; log-rank test p = 0.78). There was no interaction between the two substances.Conclusion: Our study found no evidence of a beneficial or harmful effect for beta-carotene in colorectal cancer in older male smokers, but does provide suggestive evidence that vitamin E supplementation may have had a modest preventive effect. The latter finding is in accord with previous research linking higher vitamin E status to reduced colorectal cancer risk.