Allergy-related diseases should be neither seen nor studied as isolated entities: always look for 4 components of "allergic march"

This study from Sweden evaluated 3,000 children at ages 1, 2, 4, 8 and 12 years. Parental questionnaires were used to obtain data on allergy-related diseases.

At 12 years, 58% of the children had eczema, asthma and/or rhinitis at some time of their lives. Disease turnover was high for all three diseases throughout the study.

Comorbidity increased with age, and at 12 years, 7.5% of all the children were affected by at least two allergy-related diseases.



Allergic (atopic) march (click here to enlarge the image).

Parental allergy was associated with:

- increased comorbidity
- more persistent disease
- increased the risk of having any allergy-related disease (adjusted OR 1.76) up to 12 years

Male sex was associated with an increased risk throughout childhood.

Allergy-related diseases affects a majority of children (58%). Eczema, asthma and rhinitis develop dynamically throughout childhood, and allergic comorbidity is common.

Allergy-related diseases should be neither seen nor studied as isolated entities. In any patient with one allergy-related condition, always look for the 4 components of the "allergic march":

- atopic dermatitis (eczema)
- food allergy or eosinophilic esophagitis
- allergic rhinitis
- asthma

References:

Development and comorbidity of eczema, asthma and rhinitis to age 12 - data from the BAMSE birth cohort. Ballardini N, Kull I, Lind T, Hallner E, Almqvist C, Ostblom E, Melén E, Pershagen G, Lilja G, Bergström A, Wickman M. Allergy. 2012 Feb 16. doi: 10.1111/j.1398-9995.2012.02786.x.