Finkelstein M M
Health and Safety Studies Unit, Ontario Ministry of Labour, Toronto.
CMAJ. 1995 Jan 1;152(1):37-43.
To determine whether workers in Ontario who had been exposed to silica dust and who have radiographic abnormalities are at increased risk of lung cancer.
Cohort and case-control studies of rates of death from lung cancer and cancer incidence rates; data were obtained from the Ontario Silicosis Surveillance Registry. Follow-up was through linkage to the Ontario mortality and cancer registries.
Ontario.
A total of 523 workers with radiographic abnormalities and 1568 control subjects with normal radiographic findings who had been exposed to silica dust. Matching criteria were year of birth and the requirement that the control subject have a normal radiographic finding either later than or in the same year that the radiographic abnormality was identified in the silicosis subject.
Standardized mortality ratios (SMRs), standardized incidence ratios (SIRs) and odds ratios for lung cancer.
In the cohort analysis, with the Ontario population rates as reference, the all-cause SMR was 0.96 among the workers with radiographic abnormalities and 0.51 among the control subjects. The corresponding SIRs for lung cancer were 2.49 and 0.87 (p < 0.001). In the case-control analysis the workers with silicosis were more likely than the control subjects to have been smokers, but this difference likely accounted for only a small part of the difference in the incidence of lung cancer. The relative risk of lung cancer was elevated among the workers with silicosis from the foundry, mining and nonmetallic-minerals industries; however, the number of subjects was too small for a significant difference to be detected. Among the miners exposure to radon daughters did not affect the risk of lung cancer attributable to radiographic abnormalities.
Radiographic abnormalities suggestive of exposure to silica dust are markers for increased risk of lung cancer. Physicians might thus wish to warn their patients with silica-associated radiographic abnormalities about the increased risk and to counsel those who smoke to stop.
确定安大略省接触过二氧化硅粉尘且有影像学异常的工人患肺癌的风险是否增加。
肺癌死亡率和癌症发病率的队列研究及病例对照研究；数据来自安大略省矽肺监测登记处。通过与安大略省死亡率和癌症登记处建立联系进行随访。
安大略省。
共有523名有影像学异常的工人和1568名影像学检查结果正常的对照对象，他们均接触过二氧化硅粉尘。匹配标准为出生年份，且要求对照对象的影像学检查结果正常时间晚于或与矽肺患者影像学异常确诊年份相同。
肺癌的标准化死亡比（SMR）、标准化发病比（SIR）和比值比。
在队列分析中，以安大略省人群发病率为参照，有影像学异常的工人全因SMR为0.96，对照对象为0.51。肺癌相应的SIR分别为2.49和0.87（p<0.001）。在病例对照分析中，矽肺患者比对照对象更有可能吸烟，但这种差异可能仅占肺癌发病率差异的一小部分。铸造、采矿和非金属矿物行业的矽肺工人肺癌相对风险升高；然而，受试者数量过少，无法检测到显著差异。在矿工中，接触氡子体并不影响因影像学异常导致的肺癌风险。
提示接触二氧化硅粉尘的影像学异常是肺癌风险增加的标志。因此，医生可能希望警告有二氧化硅相关影像学异常的患者肺癌风险增加，并建议吸烟者戒烟。
