[Respiratory and allergic diseases of children : Temporal trends, urban-rural differences, and in association with environmental tobacco smoke exposure].

Ten years after the establishment of health monitoring units (GME) in Bavaria, temporal trends and urban-rural differences in parent-reported respiratory and allergic diseases as well as environmental tobacco smoke (ETS) exposure in preschoolers were analyzed in an explorative manner. Furthermore, associations between diseases and ETS exposure were studied.Parent questionnaires were used as part of the school entrance examination in two cross sectional studies (S1:2004/2005, n 1 = 6350; S2:2012/2013, n 2 = 5052). Temporal trends and urban-rural-differences were tested by X2 tests. Associations between diseases and exposures were studied using multiple logistic regression analysis.The lifetime prevalence of atopic dermatitis declined from S1-S2 from 12.4 to 11.1 %, whereas those for hay fever, asthma, bronchitis and pseudocroup remained stable. In S1 and S2, bronchitis was less often reported in cities. The other diseases showed no urban-rural differences. The prevalence of children's ETS exposure at home declined from S1-S2 from 14.3 to 7.2 % and was generally higher in cities than in rural regions. There was no positive association between diseases and children's ETS exposure at home. In S2 an association was found between asthma and current parental smoking (OR = 1.60; 95 % CI = (1.10-2.32)).The GME provide important data for regional distribution of respiratory and allergic diseases and ETS exposure of preschoolers in Bavaria. The results of the study are important for further development of questionnaires, which will be used in future GME.