Urban, low-income children are at increased risk for asthma, likely due to both psychosocial and physical environmental exposures.

The Childhood Asthma Prevention Study recruited 177 low-income families of children age 9-24 months with ≥3 wheezing episodes. Half of families were randomly assigned to a year-long nurse home visitor environmental support (ES) intervention focused on reducing allergens and environmental tobacco smoke and improving illness-related caregiving. Assessments at baseline and 12 months addressed caregiver psychological resources, illness management, quality of life, and infant illness symptoms. Infant urine and household dust samples were collected, and medical records were abstracted.

At year's end, number of homes with cockroach allergen was significantly reduced (p<0.033), and dog allergen tended to be lower (p<0.069) in ES homes. Infants' urinary cotinine was significantly reduced among ES families whose caregivers had fewer psychological resources (p<0.006). Asthma Knowledge and Collaboration with Medical Provider was greater in the ES group (p's<0.04). Reports of children's symptoms did not differ across groups, but caregiver quality of life was greater for ES foreign-born families (p<0.026) and families whose children had low baseline medication levels (p<0.044). Children in the ES group had significantly higher numbers of corticosteroid bursts during the intervention year (p<0.012).

The nurse home visitor intervention successfully impacted some of the targeted variables assessed, but failed to impact caregivers' symptom reports. Higher numbers of corticosteroid bursts in the ES group may reflect better management for these infant wheezers, possibly leading to less inflammation and fewer symptoms at age 4 and 7 follow-up.