The asthma prevalence in school entering children in New York City can vary anywhere between 3% and 19% by neighborhood, and 2 to 3 times the difference in asthma risk were found in children who grew up within walking distance of each other.
Researchers compared the household presence of mouse, cockroach, dust mite, cat, and other allergens in high asthma prevalence neighborhoods to that in low asthma prevalence neighborhoods. Cockroach, cat and mouse allergens were substantially higher in homes situated in neighborhoods where asthma is more prevalent and that children living in these homes were more likely have cockroach antigen sensitization.
A total of 239 7-8 year old children were researched, 120 lived in neighborhoods with a high asthma prevalence and 119 lived in low asthma prevalence neighborhoods. A survey of symptoms reported by parents helped to determine 128 as being identified as having asthma and 111 being allocated to a control group.
Exposure to allergens was measured by the collection and analysis of samples of bed dust from the upper half of the beds of children. Sensitization was measured by blood sample screening for antibodies to a variety of household allergens. Exposure and sensitization to mouse and cockroach allergens has been shown to be linked to having asthma.
A higher prevalence of cockroach, cat and mouse allergens were found in bed dust from homes in neighborhoods with a high asthma prevalence compared to neighborhoods with a low asthma prevalence. Cockroach allergen exposure could contribute to the higher prevalence of asthma seen in some neighborhoods in New York City, and that cockroach allergen sensitivity was twice as common. There was however no significant difference in cat and mouse antigen sensitization by neighborhood.
The study results reveal that:
- Cockroach sensitization was higher in those children residing in neighborhoods having high asthma rates.
- Cockroach allergen was higher in homes of the prevalence of high asthma neighbourhoods.
- Cockroach sensitization was linked to an increased asthma risk.
- Exposure to cockroach allergens was linked to sensitization.