大量服用复合维生素增加前列腺癌风险

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http://www.medpagetoday.com/Urology/ProstateCancer/tb/5654
Mega Multivitamin Use Risks Prostate Cancer
大量服用复合维生素增加前列腺癌风险
BETHESDA, Md., May 15 -- Men who take multi-vitamin supplements more than once a day are twice as likely to die of prostate cancer as men who never take supplements, researchers confirmed. Action Points
美国马里兰州，Bethesda，5月15日--研究人员证实，一天服用一次以上复合维生素补充剂的男性死于前列腺癌的几率是不服用补充剂男性的两倍。
Explain to interested men that more than daily use of multivitamin supplements does not appear to reduce their risk of prostate cancer and may even increase it.
相关的解释是男性每天服用复合维生素补充剂一次以上不会降低其罹患前列腺癌的风险，反而会增加这种风险。
Caution patients that the study did not suggest that regular multivitamin use, whether occasionally or once daily, significantly increased risk of prostate cancer.
提醒患者注意的是，这项研究不建议经常服用复合维生素，因为不管是偶尔服用或者一天一次都会明显增加前列腺癌风险。
They were also at elevated risk of advanced prostate cancer compared with never users, reported Karla A. Lawson, Ph.D., of the National Cancer Institute here, and colleagues.
美国国家癌症研究所的Karla A. Lawson公共卫生博士及其同事报告说，他们也就患晚期前列腺癌风险升高与从不服用补充剂的人进行了比较。
The researchers reported the outcomes of the National Institutes of Health -- AARP Diet and Health Study in the May 16 issue of the Journal of the National Cancer Institute.
研究人员报告了美国国立卫生研究院的结果--美国国家癌症研究所杂志5月16日刊的AARP饮食及健康研究。
The large, prospective investigation adds credence to the possibility of harm from antioxidant supplements as found in prior systematic reviews and meta-analyses, according to an accompanying editorial.
据一位助理编辑称，与前期系统回顾研究和荟萃分析结果一样，大量前瞻性研究更加证实了抗氧化补充剂的可能害处。
The findings \"underscore the possibility that antioxidant supplements could have unintended consequences for our health,\" wrote Goran Bjelakovic, M.D., of the University of Nis, Serbia, and Christian Gluud, M.D., of the Copenhagen University Hospital.
Nis大学的Goran Bjelakovic医学博士和Copenhagen大学医院的Christian Gluud医学博士称，研究发现“强调抗氧化补充剂的作用会对我们的健康有意想不到的后果”。
The few previous prospective studies had suggested that multivitamin use may protect men from developing prostate cancer but speed its progression once begun, Dr. Lawson and colleagues wrote.
Lawson博士及其同事称，以前很少有前瞻性研究显示服用复合维生素会防止男性患前列腺癌，但一旦开始服用便会加速患病。
Because more than a third of American adults take vitamins, the researchers noted, \"any association between intake of multivitamin supplements and the risk or severity of prostate cancer would have important consequences for public health,\" the researchers wrote.
研究者称，因为三分之一以上美国成年人服用维生素，所以“关于服用复合维生素补充剂与前列腺癌发病风险或加重其风险间的任何联系都将对公共健康有重大影响”。
The prospective study included 295,344 men aged 50 to 71 and free of cancer at enrollment in 1995 and 1996.
此前瞻性研究纳入1995和1996年间年龄在50-71岁的295344名未患癌症男性。
Their multivitamin use was assessed at baseline using a self-administered, food-frequency questionnaire. Five percent used multivitamins more than seven times a week; 36% took a multivitamin daily.
通过进行自行给药，给药频率的问卷调查对人们服用复合维生素进行评价。5%的人服用复合维生素一周超过七次；36%的人每天服用一次复合维生素。
Among the participants, 41% reported using a one-a-day type supplement, 12% reported using a theragran type (vitamins plus iron) supplement, and 6% reported use of a stress-tab type supplement (primarily B vitamins). Half of the supplements used were multivitamins.
据报告，调查者中，41%的人服用一种一天一次型的补充剂，12%的人服用施尔康（维生素加铁）补充剂，6%的人服用一种压缩型补充剂（B族维生素）。所用补充剂有一半是复合维生素。
Outcomes were followed using subsequent questionnaires, Social Security Administration death records, and state cancer registries.
通过后继问卷调查，社会保障行政死亡记录及国家癌症登记得出结果。
Over five years of follow-up, 10,241 developed incident prostate cancer. These cases included 8,765 localized and 1,476 advanced cancers. A separate mortality analysis found 179 cases of fatal prostate cancer over six years of follow-up.
在五年的随访中，10241名受试者出现前列腺癌，其中8765名为局限性前列腺癌和1476名为晚期前列腺癌。一项单独的死亡率分析发现在6年的随访中有179例致死性前列腺癌病例。
Among the findings in a multivariate adjusted analysis, the researchers reported (more than daily use versus never users):
研究人员报告，在经过多变量校正分析后，结果为（每日服用复合维生素一次以上与不服用者相比）：
No association between multivitamin use and risk of prostate cancer overall (relative risk 1.06, 95% confidence interval 0.97 to 1.17).
服用复合维生素与所有的前列腺癌风险之间没有联系（相对危险度1.06，95%可信区间0.97 到1.17）。
No association between multivitamin use and risk of localized prostate cancer (RR 1.02, 95% CI 0.92 to 1.14).
服用复合维生素和局限性前列腺癌发病风险间没有联系（RR 1.02, 95% CI 0.92到1.14）
Increased risk of advanced prostate cancer (RR 1.32, 95% CI 1.04 to 1.67).
晚期前列腺癌风险增加(RR 1.32, 95% CI 1.04 到 1.67)。
Elevated risk of fatal prostate cancers (RR 1.98, 95% CI 1.07 to 3.66).
致死性前列腺癌风险增加(RR 1.98, 95% CI 1.07到 3.66).
Higher incidence rates for advanced prostate cancer (143.8 versus 113.4 per 100,000 person-years).
晚期前列腺癌发病率升高（143.8：113.4/10万人每年）。
Higher incidence rates for fatal prostate cancer (18.9 versus 11.4 per 100,000 person-years).
致死性前列腺癌的发病率升高（18.9：11.4/10万人每年）。
The associations were strongest in men with a family history of prostate cancer or those who took selenium, β-carotene, or zinc.
对于有前列腺癌家族史或补充硒，β-胡萝卜素或锌的男性，这些联系最明显。

\"Thus, excessive intake of certain individual micronutrients that are used in combination with multivitamins may be the underlying factor that is related to risk and not the multivitamins themselves,\" the researchers wrote.
研究人员称，“因此，过多摄取与复合维生素混合在一起的某种微量营养素可能是增加风险的潜在因素，而非复合维生素本身”。
Among men with prostate cancer in the family, heavy multivitamin use (more than seven times per week) more than doubled advanced prostate cancer risk (RR 2.48, 95% CI 1.45 to 4.23) and fatal prostate cancer risk (RR 16.41, 95% CI 2.62 to 102.68).
有前列腺癌家族史的男性大量服用复合维生素（一周超过七次）其患晚期前列腺癌(RR 2.48, 95% CI 1.45到 4.23)和致死性前列腺癌(RR 16.41, 95% CI 2.62到102.68)的风险增加两倍以上。
Heavy use of selenium yielded a 37% increased risk of localized prostate cancer (P=0.008 for interaction) Although based on a small sample, those who took more than seven multivitamins a week and were also taking a selenium supplement were at 5.8-fold higher risk of fatal prostate cancer than those not taking a selenium supplement (P=0.037 for interaction).
大量服用硒会导致局限性前列腺癌风险增加37% (交互作用分析P=0.008)。基于小样本分析，那些一周摄入复合维生素超过七次并同时服用硒补充剂的人，其患致死性前列腺癌的风险比那些不服用硒补充剂的人高5.8倍(交互作用分析P=0.037)。
The association between heavy multivitamin use and advanced prostate cancer was somewhat modified by β-carotene use (P=0.036 for trend).
在某种程度上大量服用复合维生素和晚期前列腺癌发病率间的联系会因服用β-胡萝卜素而减轻。
Men who used a zinc supplement in addition to heavy multivitamin use were at significantly elevated risk of fatal prostate cancer (RR 4.36, 95% CI 1.83 to 10.39 versus daily or less than daily multivitamin use).
与服用复合维生素每日一次或少于每日一次的男性相比，除服用大量复合维生素另再服用锌补充剂的男性患致死性前列腺癌的风险明显升高(RR 4.36, 95% CI 1.83到10.39)。
This \"could be due to nonessential, potentially harmful trace elements contained in zinc supplements, such as cadmium, a known carcinogen,\" the researchers said.
研究人员说，这可能归因于存在于锌补充剂中的非必需的潜在有害微量元素，例如致癌物质镉。
They noted that their study was limited by lack of information on duration of multivitamin use.
他们称，由于对人们服用复合维生素期间信息的缺乏使得研究受到限制。
Also, they said, heavy multivitamin users were more likely to have prostate cancer screening using prostate specific antigen.
他们也称，大量服用复合维生素更容易产生前列腺癌筛选所用的前列腺特异抗原。
While this could have biased diagnosis of localized prostate cancer, \"increased multivitamin use due to early symptoms of prostate cancer cannot account for the increased risk of fatal prostate cancer among heavy multivitamin users because the association persisted and even strengthened when we disregarded those diagnosed in the initial years of follow-up,\" the researchers noted.
研究人员称，虽然这可能会使局限性前列腺癌诊断出现偏差，“而加大复合维生素用量会导致前列腺癌早期症状的说法不能解释服用大量复合维生素的人其致死性前列腺癌风险增加现象，这是因为在最初几年随访中当我们忽视那些诊断结果时，这种联系却持续存在，甚至加强”。
Regardless, they concluded, \"the possibility that men taking high levels of multivitamins along with other supplements have increased risk of advanced and fatal prostate cancers is of concern and merits further evaluation.\"
不管怎样，他们总结说，“服用高剂量复合维生素同时服用其他补充剂的男性其晚期和致死性前列腺癌风险增加，这种可能性需要加以注意，并做进一步评价。”
The reason why dietary intake of vitamins has been shown beneficial with mixed or negative results for supplements, editorialists Drs. Bjelakovic and Gluud suggested, may be because of differences between natural and synthetic vitamins.
撰稿人Bjelakovic和Gluud博士认为，不管补充剂是协同还是抵消作用，饮食摄入维生素之所以会有益处，可能是因为天然维生素和合成维生素间存在差异。
\"Antioxidant supplements in pills are synthetic, factory processed, and may not be safe compared with their naturally occurring counterparts,\" they wrote.
“抗氧化补充片剂是由工厂生产的合成物质，相比于天然产物其可能不安全。
Or, they added, it could be that the populations they have been tested in already get their full daily requirement of vitamins and trace elements from diet. They pointed out that the American diet provides 120% of the recommended dietary allowances for beta-carotene, vitamin A, and vitamin C, and that dietary vitamin E deficiency has never been reported in the United States.
或者，他们补充道，受试者已经从饮食中获得了每日必需的维生素和微量元素。他们指出，对于β-胡萝卜素，维生素A和维生素C，美国饮食的拟定饮食供应量能达到120%，而且在美国也从未见有饮食中维生素E不足的报道。
They also suggested a possible mechanism for the negative findings: \"Reactive oxygen species in moderate concentrations are essential mediators of reactions by which the body gets rid of unwanted cells. Thus, if administration of antioxidant supplements decreases free radicals, it may interfere with essential defensive mechanisms for ridding the organism of damaged cells, including those that are precancerous and cancerous.\"
对于阴性结果他们也提出一种可能机制：“适当浓度的活性氧簇是机体必需的活性媒介，机体籍此清除不需要的细胞。因此，如果给予抗氧化补充剂来减少自由基，可能会影响机体的重要防御机制，影响其清除癌变前细胞及癌性细胞这些损伤细胞的作用。”
The editorialists also suggested a need for further study, possibly including testing of supplements similar to pharmaceutical products.
撰稿人也指出需要进行进一步的研究，可能包括对补充剂进行类似于药物的检测。
The research was supported by the National Cancer Institute. Neither the researchers nor the editorialists reported information on financial conflicts of interest.
此项研究由美国国家癌症研究所支持。不管研究人员还是撰稿人所报道信息都不涉及利益关系。
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Primary source: Journal of the National Cancer Institute
最初来源：国家癌症研究所杂志
Source reference:
出处：
Lawson KA, et al \"Multivitamin Use and Risk of Prostate Cancer in the National Institutes of Health - AARP Diet and Health Study\" J Natl Cancer Inst 2007;99: 754-764.
Lawson KA等“大量服用复合维生素与前列腺癌风险的美国国立卫生研究院-AARP饮食与健康研究”《国家癌症研究所杂志》2007;99: 754-764
Additional source: Journal of the National Cancer Institute
补充资料：国家癌症研究所杂志
Source reference:
出处：
Bjelakovic G, Gluud C \"Surviving Antioxidant Supplements\" J Natl Cancer Inst 2007;99:742-743.
Bjelakovic G, Gluud C“抗氧化补充剂”《国家癌症研究所杂志》2007;99:742-743. ——自丁香园