The impact of second-hand smoke on ear, nose, and throat diseases and head and neck cancers in Japan: a cross-sectional study using a questionnaire and secondary data from the national health and nutrition survey

Background: The risk of head and neck cancers (HNCs) and ear, nose, and throat (ENT) diseases due to second-hand smoke (SHS) have not been fully assessed. Objective: To determine which ENT diseases or HNCs are associated with SHS. Material and methods: Data from a survey of a cross-sectional sample of ENT patients (n = 1228) on SHS exposure were compared to control-subject data (n = 6598) from a Japan National Health Survey. Multivariate logistic regression and estimated odds ratios (ORs) determined whether SHS-disease associations were related to exposure location and disease occurrence. Results: SHS was significantly associated with acute tonsillitis (OR in workplaces, 2.24 [95% CI, 1.34–3.75]; OR in restaurants, 4.24 [95% CI, 2.50–7.19]; OR in leisure places, 4.72 [95% CI, 2.93–7.62]); recurrent tonsillitis (OR in restaurants, 4.24 [95% CI, 2.52–7.13]; OR in leisure places, 5.29 [95% CI, 3.31–8.46]); facial palsy (OR in home, 2.18 [95% CI, 1.25–3.81]; OR in leisure places, 3.41 [95% CI, 1.97–5.89]); hypopharyngeal cancer (OR in home, 2.51 [95% CI, 1.18–5.36]; OR in workplaces, 2.53 [95% CI, 1.24–5.15]); and laryngeal cancer (OR in home, 2.44 [95% CI, 1.04–5.68]; OR in leisure places, 2.25 [95% CI, 1.00–5.07]). Conclusions and significance: SHS may contribute to HNCs and ENT diseases, suggesting that merely being in the presence of smokers could increase the risk of head and neck morbidities.