No further increase in the parent reported prevalence of allergies in Bavarian preschool children: Results from three cross-sectional studies.

Background: After three decades of an increase in the prevalence of asthma and allergies, new findings show a plateau in the prevalence of industrialized nations. The objective of this study was to determine whether there was a change in the parent reported prevalence of asthma and allergies among Bavarian preschool children since 2004.

Methods: A parent questionnaire was administered as part of the Bavarian school entrance examination in three cross-sectional studies from 2004/2005, 2006/2007 and 2012/2013. The questionnaire included items on allergy testing history, identified allergens, symptoms (e.g. wheezing, itchy eyes, rash), medically diagnosed asthma, hay fever and atopic dermatitis. Logistic regression was performed to observe time patterns and adjust for risk factors.

Results: Data were available for 6350 (2004/2005), 6483 (2006/2007) and 5052 (2012/2013) individuals. Symptoms and diseases were more frequent in boys, except for allergies which affect the skin. From 2004 to 2012 the parent reported prevalence of asthma (2.6% to 2.8%), hay fever (4.7% to 4.0%) and atopic dermatitis (12.4% to 11.1%) either remained quite stable or decreased not significantly.

Conclusions: Results from these three cross-sectional surveys of parent reports suggest that the parent reported prevalences of asthma and allergies are quite stable with small fluctuations since 2004 for Bavarian preschool children. Future research is needed to determine if this trend will continue.