Bronchitis-like symptoms and proximity air pollution in French elderly

Summary Background Our aim was to explore the association between respiratory health and proximity air quality in elderly. Methods The prevalence of respiratory conditions was linked in 2104 individuals aged ≥65 years recruited in Bordeaux (3C Study) to home address concentrations of NO2 , CO, SO2 , fine particles (PM10 ), VOCs and benzene, estimated through a dispersion model combining data on background air pollution, traffic characteristics, and conditions of topographical and meteorological dispersion of air pollutants. Results Mean [minimum; maximum] values of the annual concentrations (μg/m3 ) of proximity air pollutants were respectively: 28 [18; 72.2] for NO2 , 420 [350; 1337] for CO, 7.5[5; 13.7] for SO2 , 23.1 [19; 51] for PM10 , 8.1 [0.01; 116.6] for VOCs and 1.8 [1.5; 6.9] for benzene. Using a binary logistic regression model, PM10 were significantly associated with usual cough (Odds-Ratio = 1.33 (95% confidence interval: 1.00–1.77) for exposed compared to non-exposed) and SO2 with usual cough (1.55 (1.16–2.08)) and phlegm (1.45 (1.04–2.01)). We found a 10% and a 23% increase in usual cough for a 10 μg/m3 increment in PM10 and a 1 μg/m3 increment in SO2 respectively, and a 23% increase in usual phlegm for a 1 μg/m3 increase in SO2 . A sensitivity analysis showed similar results when considering 3-year proximity pollution. A more pronounced effect of SO2 and PM10 on usual cough and phlegm was observed in woman. Conclusions Our assessment of exposure to proximity air pollution has shown an increased prevalence of bronchitis-like symptoms in elderly living in areas polluted by SO2 and PM10.