School education and allergic sensitization in adults

Background: There is evidence of an association between socioeconomic status (SES) and atopy mainly from studies in children which investigated atopic diseases and parental SES. We determined the association of allergic sensitization, as measured by skin prick test (SPT) and allergen-specific IgE (RAST), and SES in a population-based study in adults. Methods: Within a population-based, nested, case-control study, a standardized interview was performed and allergic sensitization to common aeroallergens was determined by SPT and RAST. Results: A total of 1537 adults (50.4% female, age: median 50.0, range 28-78 years) were investigated, half of whom (50.2%) exhibited at least one positive RAST result according to the study design. SPT reactivity was 37.3% in this group and was estimated to be 26.1% in the representative study base of 4178 adults. Within increasing categories of school graduation (none; after 8, 10, 13, and > 13 years), the prevalence of SPT (20.5%, 31.3%, 44.0%, 44.2%, 48.1%; P trend <0.0001) and RAST reactivity (35.0%, 48.0%, 52.3%, 48.4%, 58.4%; P trend = 0.004) increased continuously. Similar results were obtained when testing this association on the level of single allergens. After control for age, sex, and parental history of atopic diseases, all but the first odds ratios for SPT remained significant (first category = reference, 2.06, 3.21, 3.88, 3.96). The same model for RAST reactivity revealed a similar result with effect estimate for the last category being significant (first category = reference, 1.89, 2.08, 2.10, 2.81). Conclusions: Allergic sensitization (SPT and RAST) to common aeroallergens in adults follows a significant and linear association with school education.