Exposure to environmental tobacco smoke from husband more strongly impacts on the airway obstruction of nonsmoking women

Background The impact of airway obstruction of nonsmoking women caused by their husband's smoking is unclear, despite the association between environmental tobacco smoke (ETS) exposure at home and obstructive pulmonary diseases among nonsmoking women. The aim of this study was to provide evidence that ETS exposure from the husband at home has a more significant influence on the airway obstruction of nonsmoking women than other housemates. Participants and methods Nonsmoking women aged 40 years or older were recruited from the health checkup during May 2015-December 2016, Japan. They answered structured questionnaires, including ETS exposure from their husbands and other housemates (parents, siblings and dependants), and performed spirometry. We categorized the women with any history of ETS exposure from housemates into three groups (A = husband, B = others and C = both of husband and others) and defined the control group as those with no ETS exposure from housemates. Results A total of 811 nonsmoking women completed questionnaires and spirometry. The proportion of nonsmoking women who had airway obstruction (forced expiratory volume in 1 second [FEV1]/forced vital capacity [FVC] <70%) among Group A (7.5%) was significantly higher than those in the control group (1.1%, p<0.01) and Group B (0.8%, p<0.01). The proportion of airway obstruction in Group C (6.4%) was also higher than that in the control group (p<0.05) and Group B (p<0.05). ETS exposure from husband (odds ratio [OR], 3.53; 95% confidence interval [CI], 1.48-8.42) remained strongly associated with airway obstruction after multiple logistic regression analysis, adjusting for age, housemate's smoking habits, family history and ETS exposure in childhood and at work. Conclusion Nonsmoking women who were exposed to ETS from their husband had the lowest FEV1/FVC, and a higher proportion of them had airway obstruction when compared to nonsmoking women who experienced ETS from housemates other than their husbands. The findings suggest that tobacco control in husbands is the most important measure to prevent airway obstruction of nonsmoking women at home.