Bronchial hyperresponsiveness in children with atopic rhinitis: a 7-year follow-up
Background: A high prevalence of bronchial hyperresponsiveness (BHR) was found in atopic subjects with rhinitis. Those subjects may be at higher risk for developing bronchial asthma. We evaluated, in a 7-year follow-up, BHR and atopy in a homogeneous population of nonasthmatic children with allergic rhinitis (AR), and their role in asthma development. Methods: Twenty-eight children (6–15 years) with AR were studied. At enrollment (T0), skin tests, total serum IgE assay, peak expiratory flow (PEF) monitoring and methacholine (Mch) bronchial challenge were performed. BHR was computed as the Mch dose causing a 20% forced expiratory volume (FEV)1 fall (PD20FEV1) and as dose–response slope (DR…