Low traffic and respiratory symptoms among smoking females: the Hordaland Health Study.

The main aim of this study was to evaluate the prevalence of respiratory symptoms among men and women separately in areas with relatively low traffic density. Data on respiratory symptoms were collected from questionnaires in the Hordaland Health Study. A total of 16,412 individuals, 40 to 45 years, were asked to participate (response rate: 55% for men and 66% for women). Women residing in areas with the highest traffic density had increased prevalence of daily cough (18% vs 8.2%, p < .01), of cough with sputum (8.8% vs 2.8%, p < .01), and of chronic cough (11% vs 4.7%, p < .01) compared with women residing in areas with lower traffic density. The differences were most pronounced for smoking females. There were no similar findings among men. In conclusion, even within areas with relatively low environmental air pollution, respiratory symptoms was related to traffic density among smoking females.