Relationships between Specific Airway Resistance and Forced Expiratory Flows in Asthmatic Children

摘要

BackgroundThe earliest changes associated with airflow obstruction in asthmatic children are a proportionally greater reduction in FEF50% than in FEV1 using spirometry, and an increase in specific airway resistance (sRaw) using body plethysmography. Consequently, we hypothesized that sRaw could be better linked to FEF50% than to FEV1. The first aim was to assess the relationships between forced expiratory flows and sRaw in a large group of asthmatic children in a transversal study. We then performed a longitudinal study in order to determine whether sRaw of preschool children could predict subsequent impairment of forced expiratory flows at school age.