Childhood wheezing phenotypes and FeNO in atopic children at age 8

Abstract

Background

Fractional exhaled Nitric Oxide (FeNO) is a surrogate biomarker of the degree of eosinophilic airway inflammation. Using longitudinal latent class analysis, 5 wheezing phenotypes have been identified, characterized by different age of onset and prognosis.

Objectives

To assess FeNO measured at 4 and 8 years in children with different phenotypes of wheeze and atopy.

Methods

Children participated in the PIAMA study, a prospective birth cohort in The Netherlands. Respiratory health was assessed yearly by questionnaires until the age of 8 years, these data were used to identify 5 wheezing phenotypes. Associations between FeNO and wheezing phenotypes were investigated using weighted linear regression.

Results

Data on wheezing phenotypes and FeNO at 4 and 8 years was available in 588 and 973 children, respectively. Compared to the phenotype of never and transient wheeze, FeNO at 4 years was higher in intermediate onset and persistent wheeze. FeNO at 8 years of age differed significantly between all phenotypes, with highest FeNO values for persistent, intermediate onset, and late onset wheeze. Rise in FeNO from 4 to 8 years in intermediate and late onset wheezers was significantly higher compared to FeNO rise in never and transient wheezers. Stratified analyses showed that the increase in FeNO in persistent, intermediate and late onset wheeze was only present in children with allergic sensitization at 8 years.

Conclusions & Clinical Relevance

FeNO measured at 8 years was associated with specific wheezing phenotypes, only among atopic children.

© 2012 Blackwell Publishing Ltd