Regional variations and temporal trends of atopic diseases in Germany

BACKGROUND AND OBJECTIVES: Prevalence rates of atopic diseases (atopic dermatitis [AD], allergic asthma [AA], and allergic rhinoconjunctivitis [ARC]) have increased in Germany. However, there is a lack of simultaneous consideration and of precise data on the spatiotemporal variation of these diseases. This study investigates the spatiotemporal variation of atopic diseases in Germany. METHODS: Analyses based on outpatient care data (2011-2020) of all statutory health insured persons in Germany. Spatiotemporal analyses of prevalence rates were performed on county levels and statistical smoothing were applied. RESULTS: Prevalence rates increased for all three diseases. Moderate but significant (p < 0.05) correlations were among others observed between ARC and AA (r = 0.47). Correlations with the east-west gradient were significant for all diseases, meaning higher prevalence rates of AD in the east and higher prevalence rates of AA and ARC in the west. The correlation coefficients showed significant values between the north-south gradient and AD, as well as between the north-south gradient and AA, implying higher prevalences in northern Germany. CONCLUSIONS: Prevalence rates for atopic diseases have increased over the past decade. Regional patterns are different for AD and the other atopic diseases. The reasons for the increase and the variations need to be analysed in detail with a view to improving prevention and health care.