TOTAL AND SPECIFIC SERUM IGE LEVELS IN ADULTS - RELATIONSHIP TO SEX, AGE AND ENVIRONMENTAL-FACTORS

We studied total and specific serum IgE levels cross-sectionally, pote ntial predictors of obstructive lung disease, in a stratified random s ample of 18-73-year-old adults (n = 1512). The attendance rate was 84% . The total IgE level and prevalences of specific IgE antibodies again st house dust mite and cat were higher for men than for women. Specifi c IgE levels decreased by increasing age, while total IgE decreased in women only. Smokers had a higher IgE level than non-smokers, while no n-smokers had more often specific IgE antibodies against timothy and b irch than smokers. Subjects with occupational dust or gas exposure had a higher total. IgE level than unexposed. The general population prev alences were for specific IgE antibodies against timothy 45%, house du st mite 3.2%, birch 2.6%, cat dander 1.6% mould 0.2% and against any o f these 7.6%. In a multivariate analysis age, occupational dust or gas exposure as well as the interaction terms between sex and age and bet ween smoking and pack-years were independent predictors for total IgE levels. Male sex, young age, never having smoked and the season of the year were independent predictors for having one or more of the five s pecific IgE antibodies. Subjects with total serum IgE in the highest q uintile (greater than or equal to 66 kU/l) had an adjusted odds ratio of 37 (95% confidence interval: 11-120) for having one or more of the specific IgE antibodies examined, compared with those in the lowest qu intile (< 5 kU/l). Demographic and environmental factors were thus pre dictors of total and specific IgE levels in this adult community. Thes e factors should be taken into account when examining relationships be tween IgE levels, markers of allergy and inflammation, and airways dis ease.