Wartenberg D, Calle E E, Thun M J, Heath C W, Lally C, Woodruff T
Environmental and Occupational Health Sciences Institute, University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA.
J Natl Cancer Inst. 2000 Oct 18;92(20):1666-73. doi: 10.1093/jnci/92.20.1666.
Several studies have reported positive associations between environmental tobacco smoke (ETS) and increased risk of breast cancer. However, studies of active smoking and risk of breast cancer are equivocal and in general do not support a positive association. To try to resolve this paradox, we examined the association between breast cancer mortality and potential ETS exposure from spousal smoking in an American Cancer Society prospective study of U.S. adult women.
We assessed breast cancer death rates in a cohort of 146 488 never-smoking, single-marriage women who were cancer free at enrollment in 1982. Breast cancer death rates among women whose husbands smoked were compared with those among women married to men who had never smoked. Cox proportional hazards modeling was used to control for potential risk factors other than ETS exposure.
After 12 years of follow-up, 669 cases of fatal breast cancer were observed in the cohort. Overall, we saw no association between exposure to ETS and death from breast cancer (rate ratio [RR] = 1.0; 95% confidence interval [CI] = 0.8-1.2). We did, however, find a small, not statistically significant increased risk of breast cancer mortality among women who were married before age 20 years to smokers (RR = 1. 2; 95% CI = 0.8-1.8).
In contrast to the results of previous studies, this study found no association between exposure to ETS and female breast cancer mortality. The results of our study are particularly compelling because of its prospective design as compared with most earlier studies, the relatively large number of exposed women with breast cancer deaths, and the reporting of exposure by the spouse rather than by proxy.
多项研究报告称，环境烟草烟雾（ETS）与乳腺癌风险增加之间存在正相关。然而，关于主动吸烟与乳腺癌风险的研究结果并不明确，总体上不支持存在正相关。为了试图解决这一矛盾，我们在美国癌症协会对美国成年女性进行的一项前瞻性研究中，考察了乳腺癌死亡率与配偶吸烟导致的潜在ETS暴露之间的关联。
我们评估了1982年入组时无癌症的146488名从未吸烟的单婚女性队列中的乳腺癌死亡率。将丈夫吸烟的女性的乳腺癌死亡率与嫁给从未吸烟男性的女性的乳腺癌死亡率进行比较。采用Cox比例风险模型来控制除ETS暴露之外的潜在风险因素。
经过12年的随访，该队列中观察到669例致命性乳腺癌病例。总体而言，我们未发现ETS暴露与乳腺癌死亡之间存在关联（率比[RR]=1.0；95%置信区间[CI]=0.8 - 1.2）。然而，我们确实发现，20岁之前嫁给吸烟者的女性中，乳腺癌死亡率有小幅升高，但无统计学意义（RR = 1.2；95% CI = 0.8 - 1.8）。
与先前研究的结果相反，本研究未发现ETS暴露与女性乳腺癌死亡率之间存在关联。我们的研究结果特别有说服力，因为与大多数早期研究相比，其采用了前瞻性设计，有相对大量暴露于ETS的女性出现乳腺癌死亡，且暴露情况由配偶报告而非通过替代方式报告。
