Environmental risk factors of childhood asthma in urban centers.

Asthma morbidity and mortality are disproportionately high in urban centers, and minority children are especially vulnerable. Factors that contribute to this dilemma include inadequate preventive medical care for asthma management, inadequate asthma knowledge and management skills among children and their families, psychosocial factors, and environmental exposure to allergens or irritants. Living in substandard housing often constitutes excess exposure to indoor allergens and pollutants. Allergens associated with dust mites (DM) and cockroaches (CR) are probably important in both onset and worsening of asthma symptoms for children who are chronically exposed to these agents. Young children spend a great deal of time on or near the floor where these allergens are concentrated in dust. Of children (2 to 10 years of age) living in metropolitan Washington, DC, 60% were found to be sensitive to CR and 72% were allergic to DM. Exposure to tobacco smoke contributes to onset of asthma earlier in life and is a risk factor for asthma morbidity. Since disparity of asthma mortality and morbidity among minority children in urban centers is closely linked to socioeconomic status and poverty, measures to reduce exposure to environmental allergens and irritants and to eliminate barriers to access to health care are likely to have a major positive impact. Interventions for children in urban centers must focus on prevention of asthma symptoms and promotion of wellness.