Published online: March 24, 2017
Children with high asthma risk can nowadays be identified early, even at the time of the first wheezing episode. However, limitations with current childhood asthma risk indices are the requirement for several wheezing episodes and that they are mainly based on atopic characteristics, such as sensitization, eczema and parental asthma. Still, they are used for overall school-age asthma risk assessment regardless of the atopic or non-atopic asthma phenotypes. Limited data exist on risk factors for these distinct childhood asthma phenotypes, presumably because early-life risk factors for non-atopic asthma are still poorly known.
In an article published in The Journal of Allergy & Clinical Immunology (JACI), Lukkarinen and colleagues hypothesized that the first rhinovirus-induced wheezing episode would predict later atopic asthma. They used data collected on 127 steroid-naive children participating in the Vinku study of childhood asthma risk factors collected at the first severe wheezing episode (90% hospitalized/10% emergency room treated patients). The researchers identified risk factors at the first severe wheezing episode separately for atopic and non-atopic asthma at age 8 years. The study was carried out in the Department of Pediatrics at the Turku University Hospital, Turku, Finland.
The children had been followed for 7 years after the first severe wheezing episode at the median age 11 months. There was extensive data available about asthma risk factors including sensitization, viral etiology and other main asthma risk factors collected at the time of the first wheezing episode. Thereafter, asthma symptoms, medications and laboratory tests were collected from patient charts, parental interviews and at study visits during the follow-up period. At age 8 years, current asthma was diagnosed in 29% of the children, divided to atopic (15%) and non-atopic (14%) asthma, providing a high-risk setting in this population-based study.
The authors found that early-onset food sensitization, eczema and rhinovirus etiology of the first severe wheezing episode predicted the development of atopic asthma at school-age, whereas parental smoking and age <12 months predicted non-atopic asthma. The authors’ findings support the hypothesis of diverse childhood asthma phenotypes and underlying pathogenic mechanisms. They also suggested that the separate risk could be predicted using simple clinical markers, such as virus etiology and atopic status at the time of the first severe wheezing episode. These findings are important when early intervention strategies for asthma prevention and phenotype-based therapies are designed.
The Journal of Allergy and Clinical Immunology (JACI) is an official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.