The wheezing schoolchild--an undiagnosed asthmatic. A follow-up of children with parentally reported episodes of wheeze without diagnosed asthma.

Objective - To examine children aged 7-15 years with parentally reported episodes of wheeze in order to estimate the proportion of undiagnosed asthmatics in this group. Design - A cross-sectional study with clinical examination of subgroups. Setting - All children (n=832) aged 7-15 years in the municipality of Odda. Subject - Based on completed questionnaires, the children were selected to one of four groups: Children with wheeze bat no asthma (wheeze group); children with current asthma (asthma group); children with past asthma (past asthma group); and children with neither asthma nor wheeze (control group). Main outcome measures - Parental reports: of episodes of wheeze, assessment of skin prick test sensitivity, measures of lung function and exercise -induced bronchoconstriction (EIB). Results - In the wheeze group, 3 (7.5%) of 40 children were diagnosed with asthma in the 18-month period between the questionnaire survey and the examination, while 4 (10%) other children had EIB. Another 8 children (20%) reported 3 episodes of wheeze or more, and at least 1 episode duriug the 12-month period before the clinical examination. Classifying these children as asthmatics would give a proportion of 37.5% with undiagnosed asthma in the wheeze group, and the prevalence of current asthma among children aged 7-15 would rise from 2.9% based on a questionnaire survey to 4.9%. Conclusions - Using a wide definition of asthma, this study suggests that a large proportion of Norwegian children with wheeze actually have asthma.