Population Disparities in Asthma

Abstract

▪ Abstract The prevalence of asthma in the United States is higher than in many other countries in the world. Asthma, the most common chronic disease of childhood in the United States, disproportionately burdens many socioeconomically disadvantaged urban communities. In this review we discuss hypotheses for between-country disparities in asthma prevalence, including differences in “hygiene” (e.g., family size, use of day care, early-life respiratory infection exposures, endotoxin and other farm-related exposures, microbial colonization of the infant bowel, exposure to parasites, and exposure to large domestic animal sources of allergen), diet, traffic pollution, and cigarette smoking. We present data on socioeconomic and ethnic disparities in asthma prevalence and morbidity in the United States and discuss environmental factors contributing to asthma disparities (e.g., housing conditions, indoor environmental exposures including allergens, traffic air pollution, disparities in treatment and access to care, and cigarette smoking). We discuss environmental influences on somatic growth (low birth weight, prematurity, and obesity) and their relevance to asthma disparities. The relevance of the hygiene hypothesis to the U.S. urban situation is reviewed. Finally, we discuss community-level factors contributing to asthma disparities.

Repeated hospital encounters for asthma in children and exposure to traffic-related air pollution near the home

“…38 Environmental disparities, such as exposure to traffic and indoor allergens, have been proposed to explain the increased asthma burden in minority and lower socioeconomic groups. 39 Although the present findings do not support this hypothesis, the number of potentially important environmental factors that differ by communities is large 39 and mostly unmeasured in the present study. Furthermore, we speculate that these findings of smaller associations in children living in lower-income census block groups may have been attributable to 2 factors: (1) less consistent exposure as evaluated at study entry due to less stable residence and (2) less consistent outcome data due to more variable use of hospitals, including those not evaluated in this study.…”

“…We also did not have data on other known or suspected risk factors that may have confounded associations, including family history of asthma and environmental exposures (eg, second-hand smoke, aeroallergens, endotoxin, family size). 38,39 This may have led to misclassification of risk. For example, differences in the distribution of indoor and outdoor allergen triggers may have biased associations.…”

Are Building-Level Characteristics Associated with Indoor Allergens in the Household?

“…12 It is associated with physical, social, and environmental issues. [13][14][15][16][17][18][19][20][21][22] Over the past two decades, asthma morbidity and mortality within the USA have increased to epidemic proportions among all age, race, and gender groups in every region of the country. 23 High levels of indoor allergens are associated with asthma morbidity.…”

“…40,41 Such triggers include household environmental exposures, high parental stress, poor medication adherence, child behavioral or emotional concerns, and poor medical care. 3,16,21,22,[24][25][26][42][43][44][45][46][47] An emerging literature does suggest that indoor allergens associated with asthma are related to the buildings in which people live. 10,11,[48][49][50][51][52] Considerable literature firmly establishes that the presence of cockroaches and rodents (i.e., pests) is associated with higher levels of asthma morbidity.…”

Individual, Housing, and Neighborhood Correlates of Asthma among Young Urban Children

“…1 Childhood asthma is a particularly pertinent example of a disease that is "socially patterned" 2,3 : A body of research has shown that asthma is disproportionately shouldered by socially disadvantaged populations, particularly minority children living in low-income urban areas. 2,[4][5][6][7][8] Studies conducted among populations of urban children have explored correlates of childhood asthma in efforts to identify the different levels at which social, psychological, and physical factors in the urban environment increase children's risk for asthma.…”