THE RELATIONSHIP BETWEEN PARENTAL AND CHILDRENS SERUM IGE AND ASTHMA

This paper examines the familial aggregation of physician-diagnosed as thma in relation to the age- and sex-standardized total serum IgE leve ls of children and their parents in a sample of the general population in Tucson, Arizona, that has been followed in a longitudinal study fo r over 20 yr. There were 591 nuclear families containing 1,177 childre n who provided information about the presence or absence of a physicia n diagnosis of asthma. The serum IgE data were less complete: both par ents and one or more of their children in 251 of the nuclear families, containing 468 children, had serum IgE levels measured. There was a v ery strong tendency for asthmatic parents to have asthmatic children, but only a small part of this appeared to be related to the familial a ggregation of total serum IgE. In the absence of an asthmatic parent, there was a slight but significantly higher prevalence of asthma in ch ildren of whom both parents had IgE levels in the highest tertile. Ver y high rates of children's asthma depended on there being an asthmatic parent who also had at least moderate levels of serum IgE. It was als o shown that asthmatic children have considerably higher total IgE lev els than would be expected on the basis of their parents' IgE levels a lone. The data appear compatible with several familial-aggregation hyp otheses and a strong environmental influence determining which childre n are likely to develop asthma. We speculate that the inflammation in the airways of asthmatic patients itself tends to increase the serum I gE level, possibly secondary to mediators that it generates.