Children with poorly controlled asthma: Randomized controlled trial of a home-based environmental control intervention.

Abstract

Few trials have tested targeted environmental control (EC) interventions based on biomarkers of second hand smoke (SHS) exposure and allergen sensitization in reducing asthma emergency department (ED) visits in children with poorly controlled asthma. Overall, 222 children with poorly controlled asthma were randomized into a home-based EC intervention (INT) or control (CON) group and followed for ED visits over 12 months. All children received allergen-specific IgE serologic testing and SHS exposure biomarker testing to inform the EC intervention. Pharmacy data was examined for asthma medication fills. Cox proportional hazards and multivariate regression models were performed to examine factors associated with repeat ED visits. There was no difference in increased risk of >1 ED visit at 12 months between INT and CON groups. Most children (75%) had moderate/severe persistent asthma. Over half (56%) had SHS exposure and 83% tested positive for >1 allergen sensitization. Among children without SHS exposure, the median time to first recurrent ED visit differed by group (CON: 195; INT: >365 days) after adjusting for child age, allergic sensitization, medication fills prior to baseline, controller medication use, and the interaction between group status and SHS exposure. Children who had positive allergic sensitizations, younger, had increased controller medication use and randomized to the CON group and had no SHS exposure had increased risk for a repeat ED visit over 12 months. In this study, a home-based EC intervention was not successful in reducing asthma ED revisits in children with poorly controlled asthma with SHS exposure. Allergic sensitization, young age, and increased controller medication use were important predictors of asthma ED visits.