PURPOSE OF THE STUDY.
Environmental control is an accepted component of asthma management in children with atopic asthma, but it is not usually a part of management in nonatopic asthma. Air pollutants, particularly particulate matter, might have a stronger effect on nonatopic asthma and might have significant indoor sources. This study examined the effect of indoor particulate matter in children with asthma.
Studied were 150 predominantly black children from the east Baltimore, Maryland, area aged 2 to 6 years with physician-diagnosed asthma and symptoms or medication use in the previous 6 months. Most of the children were from lower-income households.
Integrated air sampling in the child's bedroom was performed over 3 days at baseline, 3 months, and 6 months, using PM10 (particulate matter that is <10 μm in diameter) and PM2.5 (particulate matter that is <2.5 μm in diameter) samples collected with personal environmental monitors. Ambient particulate matter for the study was monitored at a central site within the study area. Each child underwent baseline skin testing to a mix of 14 aeroallergens. Atopy was defined as at least 1 positive skin-test result. At baseline, 3 months, and 6 months, caregivers completed questionnaires adapted from the International Study of Asthma and Allergies in Childhood and the Children's Health Survey for Asthma Questions. Participants completed a daily activity diary during each 3-day monitoring period, including an account of the time spent in the room where monitoring was performed.
Subjects were classified as nonatopic (31%) or atopic (69%). Nonatopic children were slightly younger. Indoor PM2.5–10 concentrations were similar in atopic and nonatopic children's homes, although PM2.5 exposure was significantly higher in the homes of children with nonatopic asthma (P = .04). Concentrations of PM2.5 exceeded Environmental Protection Agency standards in 75% of the homes. There were statistically significant interactions found between both coarse and fine particulate matter levels and asthma symptoms in both atopic and nonatopic asthmatic children.
In-home particle concentrations are associated with asthma morbidity, including symptoms and use of rescue medications, among atopic and nonatopic children with asthma. Strategies for reducing and eliminating sources of indoor particulate matter pollution should be considered a priority in the management of nonatopic asthma.
This study is one of few to note that the effect of indoor air pollution is at least as important in nonatopic children with asthma. As clinicians, we often discuss secondhand smoke, which is a component of indoor particulate matter, but we also should consider other sources including cooking and cleaning products.
- Copyright © 2011 by the American Academy of Pediatrics