In the new study, conducted by researchers at Columbia University
Medical Center in New York, the authors aimed to determine the association
between fuel-related air pollution levels and acute asthma episodes, based on
the area where the patients lived. The study found that asthma prevalence and
emergency room visits for asthma varied widely in different areas.
The mean annual concentrations of nitrogen dioxide, particulate matter and
elemental carbon and the mean annual level of sulfur dioxide were significantly
higher in areas with a higher prevalence of asthma. Nitrogen dioxide and
elemental carbon particles have been associated with a greater prevalence of
emergency care for asthma. The prevalence of asthma has changed the
relationship between pollutant levels and acute illness. Relationships between
pollutants and asthma emergency care were observed only in children in areas
with lower asthma prevalence.
The researchers concluded that the association between outdoor pollutant levels
and asthma emergency care was stronger among children who lived in areas with
lower asthma prevalence compared to those with high prevalence. No significant
associations between pollution and acute asthmatic conditions in areas with a
high prevalence of asthma suggests that the influence of additional
environmental and biological factors may be greater in such areas. However,
residential street exposure to pollutants remained an important predictor of
emergency care in areas with lower disease prevalence.