Neighborhood differences in exposure and sensitization to cockroach, mouse, dust mite, cat, and dog allergens in New York City

Abstract

Background: Asthma prevalence varies widely among neighborhoods within New York City. Exposure to mouse and cockroach allergens has been suggested as a cause.

Objective: To test the hypotheses that children living in high asthma prevalence neighborhoods (HAPNs) would have higher concentrations of cockroach and mouse allergens in their homes than children in low asthma prevalence neighborhoods (LAPNs), and that these exposures would be related to sensitization and asthma.

Methods: In the New York City Neighborhood Asthma and Allergy Study, a case-control study of asthma, children 7 to 8 years old from HAPNs (n = 120) and LAPNs (n = 119) were recruited through the same middle-income health insurance plan. Children were classified as asthma cases (n = 128) or controls without asthma (n = 111) on the basis of reported symptoms or medication use. Allergens were measured in bed dust.

Results: HAPN homes had higher Bla g 2 (P = .001), Mus m 1 (P = .003), and Fel d 1 (P = .003) and lower Der f 1 (P = .001) than LAPN homes. Sensitization to indoor allergens was associated with asthma, but relevant allergens differed between LAPNs and HAPNs. Sensitization to cockroach was more common among HAPN than LAPN children (23.7% vs 10.8%; P = .011). Increasing allergen exposure was associated with increased probability of sensitization (IgE) to cockroach (P < .001), dust mite (P = .009), and cat (P = .001), but not mouse (P = .58) or dog (P = .85).

Conclusion: These findings further demonstrate the relevance of exposure and sensitization to cockroach and mouse in an urban community and suggest that cockroach allergen exposure could contribute to the higher asthma prevalence observed in some compared with other New York City neighborhoods.

Figure 1. Hypothesized mechanism of association between features of neighborhood and asthma prevalence through allergen exposure

Figure 2. Location of study participants

Each dot represents a study subject’s home and is color coded according to whether they have been classified as living in low (blue) or high (red) asthma prevalence neighborhoods. Neighborhoods are color coded according to the legend by NYC DOHMH reported asthma prevalence among 5 year-old children in 2000.

Figure 3. Cockroach (A.), Mouse (B.), Dust mite (C.), Cat (D.) and Dog (E.) allergen in the child’s bed dust by neighborhood asthma prevalence

Lines represent natural spline linear models smoothed with 3 degrees of freedom with 95% confidence intervals (gray). For figures 3D and 3E, full circles represent homes with cat or dogs, respectively, and empty circles represent those without.

Figure 3. Cockroach (A.), Mouse (B.), Dust mite (C.), Cat (D.) and Dog (E.) allergen in the child’s bed dust by neighborhood asthma prevalence

Lines represent natural spline linear models smoothed with 3 degrees of freedom with 95% confidence intervals (gray). For figures 3D and 3E, full circles represent homes with cat or dogs, respectively, and empty circles represent those without.

Figure 4. Probability of sensitization to Cockroach (A.), Mouse (B.) Dust mite (C.), Cat (D.) and Dog (E.) allergens with exposure to the relevant major allergen

Points represent allergen concentration in the bed dust on the x-axis and the absence (0) or presence (1) of IgE ≥0.35 IU/ml to the relevant allergen on the y-axis. Lines represent logistic regression models with 95% confidence intervals (gray).

Figure 4. Probability of sensitization to Cockroach (A.), Mouse (B.) Dust mite (C.), Cat (D.) and Dog (E.) allergens with exposure to the relevant major allergen

Points represent allergen concentration in the bed dust on the x-axis and the absence (0) or presence (1) of IgE ≥0.35 IU/ml to the relevant allergen on the y-axis. Lines represent logistic regression models with 95% confidence intervals (gray).