Trends in prevalence of atopic diseases and allergic sensitization in children in Eastern Germany

Abstract

Trends in prevalence of atopic diseases and allergic sensitization in children from Eastern Germany during the 1990s were analysed. The study consisted of three regional cross-sectional surveys of a total of 7,632 children (aged 5-14 yrs) in 1992-1993, 1995-1996, and 1998-1999. Information was gathered on atopic diseases and potential predictors by a parental questionnaire. Allergic sensitization for birch, grass, mite, cat, and cladosporium were assessed by radioallergosorbent test (RAST). After adjustment for age, sex and the study area of the participants, prevalence increased between the first and third survey for hay fever, for asthma and for atopic eczema. The adjusted prevalence of allergic sensitization (RAST >0.35 kU·L-1) showed a decrease, whereas the prevalence of strong sensitization (RAST ≥ 17.5 kU·L-1) increased significantly, specifically in cohorts born after 1989. Further adjustment for possible determinants of these atopic diseases did not change the trend estimates. A clear increase in the prevalence of atopic diseases, with the exception of hay fever, was observed as well as a shift towards a stronger allergic sensitization, which might affect the onset of clinical manifestations of atopic diseases. Differences in the epidemiology of respiratory symptoms, illnesses and allergies between populations living in the former East Germany and those living in the former West Germany have been reported. Among East German children, lower prevalence rates of asthma, and positive skin-prick tests were observed compared to West German children in the early 1990s [1-5]. Similarly, among East German adults, lower specific immunoglobulin (Ig) E levels and lower prevalence rates of asthma, wheezing, positive methacholine-challenge tests, allergic rhinitis, and positive skin-prick tests have been reported compared to those of West German adults [6, 7].