4.1 Primary findings
In the largest population-based cohort study on this topic to date, including 6,852 children/adolescents, we identified the association of ever eczema and eczema phenotypes with the presence of FA, asthma and hay fever. “Very early onset – persistent” eczema showed the strongest associations across all investigated allergic diseases and thus represents the phenotype at highest risk for developing allergic multimorbidity. Moreover, participants with FA observed a significantly higher prevalence of eczema, asthma and hay fever throughout childhood, comparing them to participants without FA.