[Respiratory function in students who had asthma in childhood]

Students who had asthma in childhood can be divided into three groups: "asthma-remission" group "asthma-relapsing" group and "non-asthma-remission" group. When we made inquiries about three different groups, the incidence of each group was 58%, 27% and 15%, respectively. In order to determine if childhood asthma affects respiratory function in adulthood, we measured respiratory functions by spirometry in 26 students who had asthma in childhood, and in seven control students. There was no significant difference between students with childhood asthma and control students in terms of FEV1.0% of predicted value. However, students who had asthma in childhood had lower levels of V25/HT% of predicted value in comparison with control students. The effects of deep inhalation in the three groups were evaluated by determining the values of maximal expiratory flow at 40% (MEF40) of vital capacity from partial (P) and maximal (M) flow-volume curves. There was no difference between the remission group and the control group in the MEF40 M/P ratio. This suggests that childhood asthma may deteriorate respiratory functions in adulthood by remodeling of peripheral airways.