Pollution atmosphérique, inégalités sociales de santé et asthme – ANR-05-SEST-0005

Socioeconomic gradients in health are well documented in developed countries, but incompletely explained. Moreover, many environmental exposures are suspected to be health risk factors, some of them being well-established. However, research in these different domains is essentially carried out independently. Since a part of health socioeconomic gradients may be explained by environmental exposures, our objective is to explore the relationship between socio-economic position, environmental exposure and health. We chose to study a short term effect of an environmental exposure, that is, asthma attacks and atmospheric pollution in relation to socio-economic status (SES). The design of our studies is ecological and will test the associations between i) emergency visits of physicians for asthma attacks and ii) figures of respiratory drug sales and levels of atmospheric pollution in relation to SES. The setting will be the Greater Strasbourg. The statistical unit will be the smallest area (IRIS) for which socio-economic data are available through the French National Institute of Statistics (INSEE). Data on emergency visits will be obtained from the emergency and healthcare network SOS-Médecins Strasbourg and the Strasbourg SAMU emergency service (2000-2002). Data on respiratory drug sales for 2004 will be obtained from all the 3 French Medical Insurance Systems. Levels of PM10, O3, NO2, and SO2 in each IRIS will be estimated on an hourly basis from the emission inventories and measurements of the Strasbourg Air Monitoring Association (ASPA) modelled using 2 overlaid deterministic models, CHIMERE (CNRS/INERIS) and ADMS-Urban (CERC/NUMTECH). An uncertainty and sensitivity analysis of the air contaminants modelling will be carried out, allowing analyzing the effects of modelling uncertainty on observed associations. We’ll study i) the distribution of both health indicators across different socio-economic groups; ii) the distribution of ambient air pollutants concentrations across IRISes exhibiting contrasted socio economic status; iii) the modulating role of IRISes SES on the relationship between air pollution levels and asthma attacks using both case crossover and time-series approaches. Influenza epidemics, pollen release bursts as well as meteorological factors will be taken into account in the analyses. Age and sex specific analyses will be carried out as far as possible, depending on the number of health events registered.