Lung cancer and cigarette smoking in Europe: An update of risk estimates and an assessment of inter-country heterogeneity

Ten case-control studies have been carried out in 6 European countries to i nvestigate the major risk factors for lung cancer. Carcinogenic effect from cigarette smoke was the most relevant interest in our study, which has inc luded 7,609 cases of lung cancer and 10,431 controls, mainly population bas ed. The results indicate elevated odds ratios (ORs; 23,9 among men and 8.7 among women) with attributable risks exceeding 90% for men and close to 60% for women, A large, and statistically significant, variability of the resu lts across countries was detected after adjusting for the most common confo unding variables, and after controlling, at least in part, for the instabil ity of the ORs due to the small number of non-smokers in some of the study subsets. This pattern of lung cancer risk associated with cigarettes smoke, across different European regions, reflects inherent characteristics of th e studies as well as differences in smoking habits, particularly calender p eriods of starting, and it is likely to have been influenced by effect modi fiers like indoor radon exposure, occupation, air pollution and dietary hab its. (C) 2001 Wiley-Liss, Inc.