Lung cancer and environmental tobacco smoke in a non-industrial area of China

We report results from a population-based case-control study of lung cancer and environmental tobacco smoke (ETS) among never-smokers conducted in 2 r ural prefectures of China, including 200 female and 33 male lung cancer cas es, and 407 female and 114 male controls, matched on age, sex and prefectur e of current residence. The odds ratio (OR) for ever-exposed to ETS was 1.1 9 (95% CI 0.7-2.0), with a significant trend (p < 0.05) with increasing exp osure. ORs were 1.00, 1.04, 1.13 and 1.51 for non-exposed, < 10, 10-19 and greater than or equal to 20 pack-years of ETS exposure, respectively. Exces s risks were limited to ETS exposures in childhood (less than or equal to 1 8 years of age). The OR for ever-exposed to ETS in childhood, adjusting for ETS exposure in adulthood, was 1.52 (95% CI 1.1-2.2), with a significant t rend (p < 0.01) with increasing pack-years of childhood exposure, 1.00, 1.4 3, 1.81 and 2.95, respectively. After adjustment for ETS in childhood, ther e was no excess risk from adult ETS exposure. The OR for ever-exposed to ET S in adulthood was 0.90 (95% CI 0.-1.4). These results were not affected by adjustment for type of residential dwelling, type or amount of fuel used, perceived indoor smokiness, or measures of socioeconomic status, or omittin g next-of-kin respondents. Published 2000 Wiley-Liss, Inc.(dagger)