Abstract
Asthma is a heterogeneous entity whose manifestations vary with age. However, many studies mostly include wheezing symptoms for most of them. Our objective was to examine respiratory and allergic phenotypes. To define respiratory phenotypes, we used data on respiratory symptoms since birth and at two months of birth: nocturnal cough, current cough, wheezing, current wheezing, past and current dyspnea, phlegm, bronchitis, using a latent class analysis. The Bayesian Information Criteria (BIC) was used to guide the decision of the number. In a study population of 16030 newborns in France, we classified subjects into four phenotypes: 1) non-atopic, few symptoms (prevalence: 63%), 2) severe coughers (prevalence: 10%), 3) persistent wheezing (prevalence: 9%), 4) intermittent wheezing (prevalence: 17%). Bronchiolitis, rhinitis, were significantly associated with the cluster 2 (severe coughers), compared to others phenotypes. Hospitalization and oxygen prescription were significantly associated with cluster 2. Multivariate analysis showed that being a boy (RC: 1.2[1.08-1.34] and having a reflux (RC: 1.62[1.44-1.83]) were significantly associated with severe coughers. Having a reflux (RC: 1.39[1.22-1.59]) and maternal passive smoking (RC: 1.31[1.15-1.50]) were significantly associated with persistent wheezing, and in less extent with intermittent wheezing. Apgar score was not related with any phenotype.
In a based population cohort, our study shows a high prevalence of respiratory symptoms in early life, and suggest that respiratory phenotypes could appear earlier in childhood.
- Copyright ©the authors 2016