Clinical predictors and outcomes of consistent bronchodilator response in the childhood asthma management program.

Abstract

Among asthmatic subjects, bronchodilator response (BDR) to inhaled beta(2)-adrenergic agonists is variable, and the significance of a consistent response over time is unknown. We assessed baseline clinical variables and determined the clinical outcomes associated with a consistently positive BDR over 4 years in children with mild-to-moderate persistent asthma. In the 1041 participants in the Childhood Asthma Management Program, subjects with a change in FEV(1) of 12% or greater (and 200 mL) after inhaled beta(2)-agonist administration at each of their yearly follow-up visits (consistent BDR) were compared with those who did not have a consistent BDR. We identified 52 children with consistent BDRs over the 4-year trial. Multivariable logistic regression modeling demonstrated that lower baseline prebronchodilator FEV(1) values (odds ratio, 0.71; P < .0001), higher log10 IgE levels (odds ratio, 1.97; P = .002), and lack of treatment with inhaled corticosteroids (odds ratio, 0.31; P = .009) were associated with a consistent BDR. Individuals who had a consistent BDR had more hospital visits (P = .007), required more prednisone bursts (P = .0007), had increased nocturnal awakenings caused by asthma (P < .0001), and missed more days of school (P = .03) than nonresponders during the 4-year follow-up. We have identified predictors of consistent BDR and determined that this phenotype is associated with poor clinical outcomes.