Geographic clustering of adult asthma hospitalization and residential exposure to pollution at a United States-Canada border crossing

Objectives. We conducted a case-control study of adulthood asthma and point-source respirable particulate air pollution with asthma-diagnosed case patients (n = 3717) and gastroenteritis-diagnosed control patients (n = 4129) to determine effects of particulate air pollution on public health. Methods. We used hospitalization data from Buffalo, NY, neighborhoods for a 5-year period (1996 through 2000), geographic information systems techniques, the Diggle method, and statistical analysis to compare the locations of case patients and control patients in terms of proximity to different known pollution sources in the study area. Results. We found a clustering of asthma cases in close proximity to the Peace Bridge Complex and the freeways and a dose-response relationship indicating a decreased risk of asthma prevalence the farther an individual resides from the source of exposure. Conclusions. These findings provide a basis for the development of new hypotheses relating to the spatial distribution of asthma prevalence and morbidity in this community.