Allergen Exposure in Inner Cities Varies Throughout The Nation

Inner-city children with asthma are exposed to significantly different levels of indoor allergens, depending on the area of the country and type of home in which they live. Exposure to major indoor allergens, such as dust mites, pet dander, and cockroaches, contribute to the increasing prevalence of asthma in these children.

Rebecca S. Gruchalla, M.D., Ph.D., and researchers with the Inner City Asthma Study examined the relationship between indoor allergen exposure, skin test reactivity, and asthma symptoms in children in various geographic locations across the United States. Skin tests were administered to 937 children with moderate-to-severe asthma.

Allergen levels were found to vary dramatically across the areas studied. Among the findings:

Cockroach exposure and sensitivity were highest in the Northeast, with the highest levels found in New York City.
Levels of dust mite allergens were the highest in the South and Northwest, particularly in Seattle and Dallas.
Cockroach allergen levels were higher in high-rise apartments.
Dust-mite levels were higher in detached homes.
The researchers also discovered that cockroach allergens had a greater impact on asthma than did dust mite allergens. The children whose asthma symptoms were triggered by exposure to cockroach allergens displayed more asthma symptoms, missed more school, and made more unscheduled doctors' visits because of their asthma.

Although the researchers did not find this kind of relationship between dust mites and asthma, their findings suggested that children who were allergic and exposed to dog and cat allergens have more unscheduled asthma health care visits than children who were not exposed or who are not allergic.

The study suggested that cockroaches had the greatest effect on asthma morbidity among children living in inner-city environments.

(Source: Journal of Allergy and Clinical Immunology, March 2005.)

Share this with your friends