An epidemiological study on total and specific IgE levels in Japanese schoolchildren.

Total serum IgE, and specific serum IgE against mites, Ascaris and Japanese cedar pollen were surveyed in 251 schoolchildren by a radioimmunoassay method. These children, aged from 10 to 13 years and living in a rural Japanese town, were selected according to one-third random population sample. A high concentration of total serum IgE (700 u/ml or more) was found in thirty-one children (12 X 3%). The sex ratio of these children, boys to girls, was 2 X 1:1. The cross-sectional and 6-year follow-up study of total IgE levels showed that they decreased with advancing age. Total IgE levels were significantly related to each of three specific IgE species investigated in this study. The levels of these three specific IgE's were also significantly related to each other. Schoolchildren with high specific IgE levels against mites have had significantly more asthmatic histories compared to children with low specific IgE levels. Such a relationship was not observed for total IgE levels and another two specific IgE species.