Higher family socioeconomic status (SES) has been suggested as a risk factor for allergic diseases. We investigated the effect of SES on the prevalence of allergic diseases and atopy. The study included 13-14-year-old primary school students in Kemalpaşa, Turkey. The International Study of Asthma and Allergies in Childhood phase 1 questionnaire was administered to all students to identify allergic diseases. Those identified as having allergic diseases underwent a skin prick test (SPT). Group I included students with allergic diseases and a positive SPT. Group II comprised students with allergic disease who were SPT negative. The control group was randomly selected from the students with no allergic diseases. Three weighted SES scores were calculated for each student (equally weighted, education-weighted, and social class-weighted). SES was classified as lower, middle, or upper according to the weighted SES scores. Allergic diseases were detected in 657 of the 1,373 children who participated in the study. A higher percentage of children with allergic diseases and atopy were in the lower SES group in all weighted SES analyses compared with controls (Group I: 59%, 83.1%, 67.5%; Group II: 62.9%, 80%, 63.5%; control group: 12.4%, 12.9%, 21.2%). Significantly more children with allergic and atopic diseases (Groups I and II) were in the lower SES group compared with the control group (p < 0.001). In contrast to the hygiene hypothesis, we found the incidence of atopic disease was higher in families with lower SES.

Keywords: ISAAC, allergic diseases, asthma, atopy, socioeconomic status