烏腳病盛行地區居民肺癌之長期世代追蹤研究

Since the tap water system was implemented in the endemic area of blackfoot disease along the southwest coast of Taiwan Island, the incidence of newly developed cases of blackfoot disease has been decreasing. However, the mortality from lung cancer in the endemic area remains higher than that of the general population in Taiwan. The purposes of this study includes: (1) To assess the lung cancer mortality of blackfoot disease patients, and their age-sex-residence-matched healthy controls. (2) To explore the relationship between chronic arsenic exposure and lung cancer. (3) To evaluate the risk factors associated with lung cancer in this area.
The subject was followed up in this long-term prospective study, including 257 blackfoot disease patients and 753 age-sex-residence-matched healthy contols. The analysis of mortality from lung cancer found that the lung cancer mortality of this cohort was significantly higher than that of the general population in Taiwan. The standardized mortality ratio (SMR) was 7.39 (95% confidence interval=3.39-14.05) for blackfoot disease patients. Analysis of multiple risk factors associated with lung cancer were carried out using Cox's proportional hazards model. The risk factors significantly associated with lung cancer mortality included age, cigarette smoking, arsenic related disease, and ingested arsenic exposure. After adjusting for multiple risk factors, there was still a significant dose-response relationship between chronic arsenic exposure and lung cancer. There was also an interactive effect on lung cancer between arsenic exposure and cigarette smoking.