Sociodemographic correlates of indoor allergen sensitivity among United States children

Background: Exposure to indoor allergens is associated with asthma morbidity. Nationally, asthma morbidity disproportionately affects socially disadvantaged populations, but it is unclear whether exposure to indoor allergens follows a similar pattern. Objective: We sought to examine the national prevalences and demographic correlates of sensitivity to indoor allergens related to asthma. Methods: Analysis of a cross-sectional survey of a representative sample of 4164 United States children aged 6 to 16 years who participated in allergen testing in the Third National Health and Nutrition Examination Survey from 1988 to 1994 was performed. The main outcome measures were sensitivity reactions to cockroach, dust mite, cat, and Alternaria alternata, as measured via skin prick testing. Results: Multivariate models, including sex, age, race-ethnicity, education, poverty, family history, region of country, housing age, crowding, and urban residence, revealed significant racial-ethnic disparities in sensitivity. Compared with white children, African American children had higher odds ratios (ORs) of cockroach or dust mite sensitivity (cockroach OR, 2.5 [95% CI, 1.9-3.2]; dust mite OR, 1.3 [95% CI, 1.0-1.7]), as did Mexican American children (cockroach OR, 1.9 [95% CI, 1.3-2.8]; dust mite OR, 1.6 [95% CI, 1.2-2.2]). African American children also had significantly higher odds of sensitivity to A alternata (OR, 2.1 [95% CI, 1.5-2.8]). Conclusions: African American and Mexican American children are substantially more likely than white children to be sensitized to allergens important in asthma. Differences in indoor allergen sensitivity are consistent with racial differences in asthma morbidity. Along with other data, these findings suggest that racial disparities in housing, community, or both environmental factors play a role in determining national patterns of asthma morbidity.