Asthma in Urban Children: Epidemiology, Environmental Risk Factors, and the Public Health Domain.

Asthma is the most commonly reported chronic condition of childhood in developed countries, with 6.5 million children affected in the USA. A disparate burden of childhood asthma is seen among socioeconomically disadvantaged youth, often concentrated in urban areas with high poverty rates. Host factors that predispose a child to asthma include atopy, male gender, parental history of asthma, and also race, ethnicity, and genetic and epigenetic susceptibilities. Environmental factors, such as improved hygiene, ambient air pollution, and early life exposures to microbes and aeroallergens, also influence the development of asthma. With greater than 90% of time spent indoors, home exposures (such as cockroach, rodent, and indoor air pollution) are highly relevant for urban asthma. Morbidity reduction may require focused public health initiatives for environmental intervention in high priority risk groups and the addition of immune modulatory agents in children with poorly controlled disease.