PURPOSE OF THE STUDY.
To evaluate phenotypic variation of rhinitis in relation to natural course and comorbid allergic diseases in preschool and early school age children.
Subgroup of a Swedish population-based birth cohort (N = 4089) born from 1994 through 1996 in Stockholm, Sweden; 2024 children were included based on available questionnaire data and blood analysis at 0, 4, and 8 years of age.
This is a prospective, population-based study that analyzed data collected longitudinally from a birth to age 8 years. Baseline data were collected at enrollment with further assessment via questionnaires mailed to subjects at ages 1, 2, 4, and 8 years with regard to allergy-related disease manifestations. At age 4 and 8 years, subjects with reported allergic disease were invited for an in-person visit that included (1) ISAAC-rhinoconjunctivitis questionnaire, (2) clinical assessments for asthma, eczema, food allergy, and oral allergy syndrome, and (3) blood samples for specific IgE to 8 inhalant allergens (Phadiatop test followed by specific ImmunoCAP IgE to individual allergens). Subjects were divided into 4 rhinitis groups: allergic rhinitis (AR), nonallergic rhinitis (NAR), allergic sensitization without rhinitis (AS), and neither rhinitis nor sensitization.
The median age at enrollment was 3 months. The proportion of children with AR increased from 5.4% to 14% from age 4 to 8 years; there was a slight decrease from 8.1% to 6.3% for NAR. From age 4 years to age 8 years, in children with (1) AR, 87% had persistent disease; (2) NAR, 73% underwent remission and 5.6% developed AR; (3) AS, 56% developed AR including 49% remaining after others were excluded for other atopic disease; and (4) no rhinitis or sensitization, 4% developed AR. Both AR and NAR were associated with asthma, eczema, and food allergy, and 25% of 8-year-olds with AR also had oral allergy syndrome due to birch pollen sensitization.
Fewer preschool age children with AR experienced remission compared to those with NAR. Allergen sensitization, and not symptoms of rhinitis, preceded development of AR. Oral allergy syndrome was common among children with AR in Sweden.
This large, longitudinal study of young children provides important clinical information regarding rhinitis symptoms and the natural history of atopic disease. In particular, few children with AR and early allergen sensitization at age 4 years experience remission by age 8 years, yet most children with NAR experience resolution of symptoms during the same time frame. These prognostic factors support early evaluation, testing, intervention, and consistent follow-up of children with AR and allergen sensitization. Oral allergy syndrome may be an important comorbid factor in birch-sensitized children but cannot be generalized to other inhalant allergens or non-Swedish populations. The major limitation of the study is the basis of data collection from questionnaires; however, these data combined with sensitization data and longitudinal symptoms profiling support the diagnostic categories used and the conclusions gained.
- Copyright © 2012 by the American Academy of Pediatrics