Hackshaw A K
Department of Environmental and Preventive Medicine, Wolfson Institute of Preventive Medicine, St Bartholomew's, London, UK.
Stat Methods Med Res. 1998 Jun;7(2):119-36. doi: 10.1177/096228029800700203.
The evidence from epidemiological studies, studies of biochemical markers of exposure and toxicological studies, confirm that there is a causal association between the risk of lung cancer and exposure to environmental tobacco smoke. Nonsmokers can inhale and metabolize carcinogens in tobacco smoke and other markers of environmental tobacco smoke inhalation (nicotine and cotinine) are raised in nonsmokers exposed to environmental tobacco smoke. In epidemiological studies of women who are lifelong nonsmokers, there is a statistically significant excess risk of lung cancer (24%, 95% confidence interval 13-36%) from exposure to environmental tobacco smoke from the spouse and this increases with the number of cigarettes smoked and duration of the marriage. Misclassification bias (women who smoke but claim to be lifelong nonsmokers) and dietary confounding are unlikely to explain the association; after adjustment for both, the risk of lung cancer from environmental tobacco smoke exposure was still statistically significant. In any event, their effects on the risk of lung cancer in the epidemiological studies are balanced out by allowing for background exposure to environmental tobacco smoke (that is, other than from the spouse) in the reference group; the excess risk after allowing for all three is an estimated 26% (95% confidence interval 7-47%), similar to the adjusted figure of 24%. In Britain, about one in every six nonsmokers are exposed to tobacco smoke from smokers in the home. Passive smoking is an avoidable cause of mortality and morbidity. Prevention strategies to reduce the amount of cigarette smoking in public places should be part of public health policy.
流行病学研究、接触生物化学标志物的研究以及毒理学研究的证据证实，肺癌风险与接触环境烟草烟雾之间存在因果关联。不吸烟者能够吸入并代谢烟草烟雾中的致癌物，并且接触环境烟草烟雾的不吸烟者体内其他环境烟草烟雾吸入标志物（尼古丁和可替宁）水平会升高。在针对终身不吸烟女性的流行病学研究中，因接触配偶的环境烟草烟雾而患肺癌的风险在统计学上显著增加（24%，95%置信区间为13 - 36%），且这种风险会随着吸烟量和婚姻持续时间的增加而上升。错误分类偏差（吸烟但声称自己终身不吸烟的女性）和饮食混杂不太可能解释这种关联；在对这两者进行调整后，因接触环境烟草烟雾而患肺癌的风险在统计学上仍然显著。无论如何，在流行病学研究中，通过在参照组中考虑背景环境烟草烟雾暴露（即除配偶之外的暴露），它们对肺癌风险的影响会相互抵消；在考虑所有这三种因素后的额外风险估计为26%（95%置信区间为7 - 47%），与调整后的24%相近。在英国，每六名不吸烟者中约有一人在家中接触吸烟者的烟草烟雾。被动吸烟是一种可避免的死亡和发病原因。减少公共场所吸烟量的预防策略应成为公共卫生政策的一部分。
