温石棉与肺癌关系的巢式病例对照研究

Nested case-control study of chrysotile and lung cancer

目的探讨单纯接触温石棉与肺癌发病的关系。方法按照巢式病例对照的研究方法,从一个追踪了30年接触温石棉的男性固定队列中,收集所有的肺癌患者作为病例组,按1:4的配对比例在该队列中选取非癌症者作为对照组,配对因素为同性别、年龄相差<5岁、工龄相差<5年、吸烟情况一致。结果研究队列中收集到40例肺癌病例,发病水平高于全国平均水平[标化死亡比(SMR)= 1.77]。肺癌发病密度由高到低的工种分别是原料工(741.5/10万人年)、梳纺工(424.3/10万人年)、编织工(365.0/10万人年)、维修工(285.5/10万人年),与接触温石棉的浓度高低一致。与低浓度接触组比较,高浓度接触组发生肺癌的相对危险度(OR)为3.7,95%可信区间为2.30～8.16,差异有统计学意义(P<0.01)。结论单纯温石棉接触能增加工人肺癌发病的危险性。

Objective To investigate the relationship between simple exposure to chrysotile and lung cancer. Methods The nested case-control study method was used. All of lung cancer cases collected from a male fixed prospective cohort with follow-up of 30 years served as cases, and a 1：4 matched proportion was used to select non-cancer case as controls. Controls matched for sex, age （±5 years old）, work time （±5 years） and smoking were collected in the same cohort. Results Forty cases died of lung cancer in the study cohort, and the incidence was higher than the average incidence （SMR=1.77）. The top four work types of death density were raw material （741.5）, combing and spinning （424.3）, weaving （365.0）, and repairing （285.5）, which was consistent with exposed level. According to the exposed level of chrysotile, the research objects were divided into the high level group and the low level group. The result demonstrated that lung cancer incidence of the high exposed level group of chrysotile was higher （OR=3.7, 95%CI： 2.30-8.16）, compared with the low exposed level group. Conclusion Simple exposure to chrysotile can increase the risk of lung cancer for workers who are exposed to chrysotile.