Improvement in bronchial hyperresponsiveness with inhaled corticosteroids in children with asthma: importance of family history of bronchial hyperresponsiveness.

The extent of improvement in bronchial hyperresponsiveness (BHR) with corticosteroids varies considerably among patients with asthma, although predictive factors for improvement are largely unknown. We tested the hypothesis that the improvement may vary according to family history of BHR. Children with atopic asthma (n = 121) received inhaled budesonide (800 micro g per day) regularly for 6 months. Methacholine provocative concentration causing a 20% fall in FEV(1) was measured before treatment and again after 3 and 6 months of treatment. A methacholine challenge test was also performed in each patient's parents, and the results were analyzed with regard to their children's response to corticosteroid therapy. When the children were classified into large (n = 40) and small (n = 40) improvement groups after 6 months of treatment, the prevalence of BHR and the bronchial responsiveness index were higher in parents of the small improvement group (28.8%, 1.145 +/- 0.104) than in parents of the large improvement group (6.3%, 1.095 +/- 0.064; both, p < 0.01). The magnitude of improvement in BHR at 6 months was lower in children with at least one parent with BHR (n = 45; 1.666 +/- 1.244 doubling doses) than in children with non-BHR parents (n = 76; 2.531 +/- 1.726, p < 0.01). Our results suggest that a family history of BHR may be an important factor in the sensitivity of BHR of individuals with asthma to inhaled corticosteroids.