Residence near a Major Road and Respiratory Symptoms in U.S. Veterans

Background: There is evidence that exposure to motor vehicle exhaust is associated with respiratory disease. Studies in children have observed associations with wheeze, hospital admissions for asthma, and decrements in pulmonary function. However, a relationship of adult respiratory disease with exposure to vehicular traffic has not been established. Methods: We studied a sample of U.S. male veterans drawn from the general population of southeastern Massachusetts. Information on respiratory symptoms and potential risk factors was collected by questionnaire. We assessed distance from residential addresses to major roadways using geographic information system methodology. Results: Adjusting for cigarette smoking, age, and occupational exposure to dust, men living within 50 m of a major roadway were more likely to report persistent wheeze (odds ratio [OR] = 1.3; 95% confidence interval [CI] = 1.0-1.7) compared with those living more than 400 m away. The risk was observed only for those living within 50 m of heavily trafficked roads (≥10,000 vehicles/24 h): OR = 1.7; CI = 1.2-2.4). The risk of patients experiencing chronic phlegm while living on heavily trafficked roads also increased (OR = 1.4; CI = 1.0-2.0), although there was little evidence for an association with chronic cough. This association was not dependent on preexisting doctor-diagnosed chronic respiratory or heart disease. Conclusions: Exposure to vehicular emissions by living near busy roadways might contribute to symptoms of chronic respiratory disease in adults.