Growing interest is accorded to drug deliveries as a public health indicator. Stronger frequency of drug deliveries compared with more serious events (eg, death, hospitalization) and their likely higher sensitivity to risk factors (eg, air pollution) suggest strong potential of this indicator for small-area epidemiologic studies. As part of the PAISA (Air Pollution and Socioeconomic Inequalities in Asthma) project, we studied the relationships between rates of short-term bronchodilatators deliveries (specific of asthma attacks treatment in people aged 40 or less) geocoded by small areas and contextual socioeconomic status in an eastern France conurbation of 450,000 inhabitants.
Material and Methods:
We obtained from the main 5 French medical insurance systems the number of short-term bronchodilatator boxes per IRIS neighborhood (∼2000 inhabitants, comparable to US Census Block Group) delivered to people aged 0 to 40 during year 2004.Total number of boxes was 17,614. Contextual socioeconomic status was measured by a composite index built by principal component analysis from 19 socioeconomic variables at the IRIS resolution.
Positive spatial autocorrelation was observed between adjacent IRIS for the socioeconomic index, but not for rates of short-term bronchodilatator deliveries. Rates of short-term bronchodilatator deliveries slightly increased as contextual socioeconomic level decreased. Pearson correlation coefficients seem to be modest but statistically significant for the 3 age groups considered (age 0–10, R = 0.28, P < 0.01; age 10–19, R = 0.17, P < 0.05; age 20–39, R = 0.30, P < 0.01) and for the whole population aged 39 or less (age-adjusted standardized incidence ratio; R = 0.31 P < 0.01).
These socioeconomic gradients are consistent with (although less marked than) those observed in the same conurbation for rates of emergency calls for asthma. Further studies will explore the relationships between air pollution concentrations and short-term bronchodilatator deliveries in IRIS of contrasted socioeconomic level.