Purpose of the Study. To examine parental factors that influence bronchial asthma and immunoglobulin E (IgE) levels in their children.
Methods. The data in this study were derived from the Tucson Epidemiological Study of Airways Obstructive Diseases since 1972. Eleven evaluation periods have been performed since that time. Asthma histories were established by questionnaire. IgE levels were obtained in 738 children, 1043 fathers, and 1261 mothers. IgE levels were determined by paper radioimmunosorbent (PRIST) technique. IgE Z scores were established. An IgE Z score is the number of standard deviations IgE differs from matched age and sex-matched subjects and log corrected. Skin tests were performed by prick technique to house dust, mold, grass, tree and weed mix and appropriate controls.
Results. The percentage of children with bronchial asthma increased with the presence of asthma in parents so that 11.5% of children with asthma occurred in families with no parental asthma compared with 48.6% when both parents had asthma. The rate of childhood bronchial asthma was significantly related to parental IgE levels only when the mother and father had bronchial asthma (43% vs 20%) and much less so (22% vs 10%), when there was no parental asthma. In addition, asthma in the child proved to be a highly significant determinant of the child's IgE Z score, even after correcting for parental IgE Z score. The presence of atopy (ie, positive skin tests) was also not a significant determinant of IgE levels in asthmatic children.
Discussion. The authors conclude that the inheritance of IgE is only one factor related to the development of asthma, and is limited as a predictor.