Atopy in infancy predicts the severity of bronchial hyperresponsiveness in later childhood

We have prospectively followed 52 children of atopic parents from birth to age 7 years, documenting clinical atopic disease and allergen skin test reactions. We found bronchial hyperresponsiveness (BHR) to histamine in 13 (25%) of the children at 7 years of age with 25 (48%) being atopic on skin testing and 15 (29%) having current wheeze, whereas 30 children (58%) had wheezed at some time during this period. BHR was significantly associated with wheeze and atopy at 5 and 7 years of age, but not during infancy. The six children with moderate to severe BHR (provocative dose causing a 20% fall in FEV1 less than 0.8 mumol) formed a distinct subgroup with significantly more wheeze and atopy both during infancy and at 5 years of age when these children were compared to children with milder degrees of BHR. The group with moderate to severe BHR also differed significantly from the nonhistamine-reactive group, whereas children with milder degrees of BHR were not significantly different. We conclude that subjects most likely to develop the more severe degrees of BHR during later childhood are children who manifest atopy in infancy.