The natural course of cow's milk allergy and the development of atopic diseases into adulthood

Background: Previous studies have investigated the natural course of cow's milk allergy (CMA) and development of atopic diseases into adolescence. Studies with long-term follow-up into adulthood are lacking. The aim of this study was to investigate (a) the natural course of CMA in a 1-year birth cohort of Danish children from birth until 15 and 26 years of age and (b) the development of atopic diseases in a group of children with CMA (group A) compared to a random sample of 276 children from the same birth cohort (group B). Methods: A birth cohort of 1749 newborns was investigated prospectively for the development of CMA and atopic diseases. During the first year of life and at 18 months and 3, 5, 10, 15, and 26 years of age, questionnaire-based interviews, physical examination, skin prick tests, and specific IgE testing, and from 10 years also spirometry, were carried out. Results: Thirty-nine (2.2%) were diagnosed with CMA. The recovery rate was 87%, 92%, and 97% at 3, 5, and 26 years of age. Compared to group B, group A had significantly (P <.05) higher prevalence of asthma and rhinoconjunctivitis at 15 years of age, and at 26 years of age, group A had significantly higher prevalence of asthma and atopic dermatitis. The follow-up rate was 85% (A) and 70% (B). Conclusion: CMA has a good prognosis regarding recovery rate. However, CMA, especially IgE-mediated, in early childhood predicts a high prevalence of atopic diseases into adulthood.