RELATION BETWEEN EXPOSURE TO ENVIRONMENTAL TOBACCO-SMOKE AND LUNG-CANCER IN LIFETIME NONSMOKERS

To assess the relation between exposure to environmental tobacco smoke throughout life and lung cancer in lifetime nonsmokers, the authors c onducted in-person interviews with 41 male and 69 female never-smoking lung cancer cases and 117 male and 187 female never-smoking controls between 1983 and 1990 as part of a hospital-based case-control study o f tobacco-related cancers. Cases had newly diagnosed, histologically c onfirmed primary carcinoma of the lung. Controls were matched to cases on age (+/-5 years), sex, race, hospital, and year of interview. Subj ects were asked about environmental tobacco smoke exposure in childhoo d, in adulthood at home, in different jobs, and in transportation and social situations. In addition to amount smoked by family members in t he subject's presence, subjects were asked to rate the intensity of ea ch exposure, and married subjects were asked whether their spouse smok ed in the bedroom, Several independent indicators of exposure to smoki ng by spouses were strongly correlated, thereby increasing confidence in the classification of exposure status. The reproducibility of envir onmental tobacco smoke variables was good for qualitative measures (ye s/no), in agreement with previous studies, There were few associations of exposure in specific settings with lung cancer, Males whose wives smoked had an odds ratio of 1.60 (95% confidence interval (CI) 0.67-3. 82) and females whose husbands smoked had an odds ratio of 1.08 (95% C I 0.60-1.94). While this study had limited sample size, the pattern of odds ratios shows little indication of an association of environmenta l tobacco smoke with lung cancer in nonsmokers.