The National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands.
Department of Public Health, Erasmus MC, Rotterdam, The Netherlands.
Int J Cancer. 2010 Apr 15;126(8):1928-1935. doi: 10.1002/ijc.24924.
The aim of this study is to investigate to what extent occupational exposures may explain socioeconomic inequalities in lung cancer incidence after adjusting for smoking and dietary factors. Analyses were based on a subsample of the European Prospective Investigation into Cancer and Nutrition (EPIC study), a prospective cohort. The analyses included 703 incident lung cancer cases among men in Denmark, the United Kingdom, Germany, Italy, Spain and Greece. The socioeconomic position was measured using the highest level of education. The estimates of relative indices of inequality (RII) were computed with Cox regression models. We first adjusted for smoking (with detailed information on duration and quantity) and dietary factors (fruits and vegetables consumption) and then for occupational exposures. The exposure to three carcinogens [asbestos, heavy metals and polycyclic aromatic hydrocarbons (PAH)] was analyzed. The occupational exposures explained 14% of the socioeconomic inequalities remaining after adjustment for smoking and fruits and vegetables consumption. The inequalities remained nevertheless statistically significant. The RII decreased from 1.87 (95% CI: 1.36-2.56) to 1.75 (1.27-2.41). The decrease was more pronounced when adjusting for asbestos than for heavy metals or PAH. Analyses by birth cohort suggested an effect of occupational exposures among older men, while due to small number of endpoints, no conclusion could be drawn about the role of occupational exposures in educational inequalities among younger men. Our study revealed that the impact of occupational exposures on socioeconomic inequalities in cancer incidence, rarely studied until now, exists while of modest magnitude.
本研究旨在探讨在调整吸烟和饮食因素后，职业暴露在多大程度上可以解释肺癌发病率的社会经济不平等。分析基于欧洲癌症与营养前瞻性调查（EPIC 研究）的一个亚组，这是一个前瞻性队列。分析包括丹麦、英国、德国、意大利、西班牙和希腊的 703 例男性肺癌新发病例。社会经济地位采用最高教育水平衡量。相对不平等指数（RII）的估计值通过 Cox 回归模型计算。我们首先调整了吸烟（包括吸烟时间和吸烟量的详细信息）和饮食因素（水果和蔬菜的摄入量），然后调整了职业暴露。分析了三种致癌物质（石棉、重金属和多环芳烃）的暴露情况。职业暴露解释了调整吸烟和水果及蔬菜摄入量后仍存在的 14%的社会经济不平等。不平等仍然具有统计学意义。RII 从 1.87（95%CI：1.36-2.56）降至 1.75（1.27-2.41）。与重金属或 PAH 相比，调整石棉后 RII 的下降更为明显。按出生队列进行的分析表明，职业暴露对老年男性的社会经济不平等有影响，而由于终点数量较少，无法得出职业暴露在年轻男性教育不平等中的作用的结论。我们的研究表明，职业暴露对癌症发病率的社会经济不平等的影响确实存在，尽管影响程度较小，但直到现在才对此进行了研究。
