Lifetime Increased Risk of Adult Onset Atopic Dermatitis in Adolescent and Adult Patients with Food Allergy.

Food allergy can result in life-threatening anaphylaxis. Atopic dermatitis (AD) causes intense itching and impaired quality of life. Previous studies have shown that patients with classical early-onset AD tend to develop food allergy and that 10% of adults with food allergies have concomitant AD. However, it is not known whether late-onset food allergy leads to adult-onset AD, a recently recognized disease entity. Using an initial cohort of one-million subjects, this study retrospectively followed-up 2851 patients with food allergy (age > 12 years) for 14 years and compared them with 11,404 matched controls. While 2.8% (81) of the 2851 food allergy patients developed AD, only 2.0% (227) of the 11,404 controls developed AD. Multivariate regression analysis showed that food allergy patients were more likely to develop AD (adjusted hazard ratio = 2.49, p < 0.0001). Controls had a 1.99% risk of developing AD, while food allergy patients had a significantly higher risk (7.18% and 3.46% for patients with ≥3 and <3 food allergy claims, respectively) of developing adult-onset AD. This is the first study to describe the chronological and dose-dependent associations between food allergy in adolescence and the development of adult-onset AD.