Allergic rhinitis and allergic sensitisation are still increasing among Danish adults

Abstract Background Only a limited number of studies have included objective measures of allergic sensitisation (such as skin‐prick test [SPT] and serum specific IgE [sIgE]) when studying time trends in allergic respiratory disease in adults within the current millennium. Methods Five health examination studies of random samples of individuals aged 18‐69 years resident in the Copenhagen region were conducted in 1990‐1991, 2006‐2008, 2010‐2011, 2012‐2015, and 2016‐2017. Allergic sensitisation was defined by sIgE (in 1990‐1991, 2006‐2008, and, 2012‐2015) or SPT (in 2006‐2008, 2010‐2011, and 2016‐2017) to at least one of the allergens: birch, grass, house dust mite, or cat. Allergic rhinitis was defined as sensitisation and self‐reported nasal symptoms. Results The age‐ and sex‐standardised prevalence of sIgE‐defined sensitisation increased from 16% in 1990‐1991, to 26% in 2006‐2008, and to 29% in 2012‐2015. The age‐ and sex‐standardised prevalence of SPT‐defined sensitisation increased from 27% in 2006‐2008, to 28% in 2010‐2011, and to 32% in 2016‐2017. Changes in sIgE‐defined and SPT‐defined allergic rhinitis showed similar increasing trends. Conclusion The prevalence of allergic sensitisation and allergic rhinitis increased in a general adult Danish population over the last three decades and has thus continued to increase in the current millennium.