Incidence and Remission of Atopic Dermatitis in a German Birth Cohort

Patterns of incidence and factors associated with remission of atopic dermatitis (AD) from birth to adulthood remain understudied.

To examine incidence of AD, its remission probability and trajectories, and early-life factors associated with it in a prospective study from birth to 30 years.

This cohort study used data from the population-based Multicenter Allergy Study (MAS), which recruited full-term newborns from 5 German cities in 1990. Generally healthy newborns were enrolled; the sample was slightly enriched for allergy risk, with more than a third of participants born with 2 parents or siblings with allergies. Until age 30 years, participants were assessed by parental or self-report questionnaires (20 times) and clinical evaluations, including serum samples (9 times).

Age, sex, age of AD onset, parental allergy status, early-life sensitization against common food and aero-allergens, rhinitis during ages 3 to 5 years, and asthma at age 6 years.

AD was determined by standardized questionnaire and doctor's diagnoses. AD remission was defined as being symptom-free for at least 12 months.

Among 1314 recruited participants, 707 (57%) had 1 or 2 allergic parents. Overall, 482 (37%) participated at the 30-year follow-up. The cumulative incidence of AD during the first 5 years was 57% (402 participants) with 1 or 2 allergic parents and 43% (225 participants) with nonallergic parents. The yearly rate of new AD cases declined from age 2 until 13 years and increased slightly thereafter. Among 529 participants with AD onset in the first 5 years of life, 459 (87%) reported no symptoms at age 20 and 30 years. Using data from 658 participants, 4 remission trajectories were identified: early childhood, early school age, substantial adolescence, and partial adulthood remission. Onset within first 2 years of life (adjusted risk ratio [aRR], 1.59; 95%- CI, 1.12-2.26), female sex (aRR, 1.56; 95% CI, 1.23-2.00), early allergic sensitization against at least 1 common aero- or food allergen (aRR, 1.95; 95% CI, 1.25-3.05), asthma at age 6 years (aRR, 2.22; 95% CI, 1.70-2.89), and allergic rhinitis at ages 3 to 5 years (aRR, 1.54; 95% CI, 1.21-1.95) were associated with the persistent phenotype.

In this cohort study of children with allergic diseases, AD before school age was generally associated with a favorable long-term prognosis. However, remission was less likely in female participants, those with onset before age 2 years, those with specific serum antibodies to common allergens before school age, or those with allergic comorbidity, highlighting the need for increased clinical attention and further investigation into underlying mechanisms.