PURPOSE OF THE STUDY.
To determine if there is a temporal relationship in the development of allergic sensitization and rhinovirus-induced wheezing.
There were 289 children studied who were part of a group of children at high risk for asthma and allergies who were enrolled at birth and followed prospectively in the Childhood Origins of Asthma (COAST) study.
Children were followed for the first 6 years of life. Specific viral pathogens were identified in 90% of wheezing episodes during the first 3 years of life (nearly all outpatient illnesses). Peripheral blood was drawn annually to assess for aeroallergen sensitization.
Sensitized children were at significantly greater risk for viral wheeze than nonsensitized children (hazard ratio [HR] 1.9; 95% confidence interval [CI], 1.2–3.1). Looking at specific viral infections, allergic sensitization was associated with increased risk of wheezing from human rhinovirus (HR 2.3; 95% CI, 1.4–4.0) but not respiratory syncytial virus (HR 1.6; 95% CI, 0.87–2.9). Conversely, viral wheezing was not associated with increased risk of allergic sensitization (HR 0.76; 95% CI, 0.5–1.1).
Allergic sensitization increases the risk for all viral wheezing, especially for human rhinovirus wheezing but not respiratory syncytial virus wheezing.
Allergic sensitization and viral wheezing early in life have both been associated with increased risk for child-onset asthma. This study is novel in that it is the first prospective cohort to identify allergic sensitization preceding viral wheezing. However, there are some previous data from another study finding severe respiratory syncytial virus bronchiolitis to be a risk factor for subsequent wheezing. If allergic sensitization is a primary event in the pathway to childhood asthma, it then would become a primary target for prevention.
- Copyright © 2012 by the American Academy of Pediatrics