Methods: 100 anthroposophic, 209 partly anthroposophic and 165 non-anthroposophic children from the ALADDIN cohort were included. Allergen specific IgE (cut-off level ≥0.35 kUA/L ) against food- (hen's egg, cow's milk and peanut), animal- (cat and dog) and pollen (birch and timothy) allergens was analyzed in blood samples at 6, 12, 24 and 60 months of age. Incidence and prevalence of sensitization to the three categories of allergens was calculated for the three lifestyle groups at the different ages. Generalized Estimating Equations (GEE) models were used to test if the association between lifestyle and prevalence of allergen sensitization differed with age of the child.
Results: In all three lifestyle groups, food sensitization occurred earlier than sensitization to animal and pollen allergens. A high incidence, 33-35 cases/100 person years, of food sensitization was seen among the non-anthroposophic children compared to only 3 cases/100 person years in the anthroposophic group and 14-16 cases/100 person years in the partly anthroposophic group up to one year of age. There was a significant impact of age on the lifestyle association with food (p=0.02), but not animal (p=0.89) or pollen allergen sensitization (p=0.91).
Conclusions: A low incidence of sensitization to food during the first year of life could to substantially explain the reduced risk of allergen sensitization seen among children of families with an anthroposophic lifestyle.