PURPOSE OF THE STUDY.
Several “wheeze phenotypes” have been described in early childhood based on age of onset and persistence of wheezing. These include never/infrequent wheeze, early transient wheeze (begins in the first 12 months and resolves by age 3 years), early persistent wheeze (begins in the first 6 months), intermediate-onset wheeze (begins at around 18 months), and late-onset wheeze (begins after age 4 years). What becomes of these children’s lung function over time?
An Australian prospective birth cohort of 620 high-allergy-risk children (at least 1 first-degree family member with a history of eczema, asthma, allergic rhinitis, severe food allergy, or any combination of these).
Respiratory symptoms and spirometry were recorded at 12 and 18 years. Relationships were assessed comparing wheeze phenotypes and lung function.
Deficits in expected growth of lung function, measured by change in forced expiratory volume in 1 second (FEV1) between 12 and 18 years, were found for early persistent (reduced 290 mL; 95% confidence interval [CI], 82–498), intermediate-onset (reduced 210 mL; 95% CI, 62–359), and late-onset wheeze (reduced 255 mL; 95% CI, 69–442). Current asthma risk was increased for all phenotypes except early transient, which was also not associated with lung function deficits at 12 or 18 years.
This is the first study to show that persistent childhood wheeze phenotypes were associated with deficits in the growth of FEV1 through to late adolescence. In contrast, early transient wheeze was found to be a benign disorder for adolescent respiratory health.
It is troubling that young children with persistent wheeze show marked reduction in lung function/growth as adolescents. This clearly emphasizes the importance of serial spirometry to identify children with declining lung function in whom more aggressive management of their asthma may prevent this. Although it is reassuring that those with early transient wheeze do not show such a decline in lung function, other studies have shown a significant rate of relapse of asthma in adults who had “outgrown” their childhood disease.
- Copyright © 2015 by the American Academy of Pediatrics