DOES RACE IMPACT THE RELATIONSHIPS BETWEEN FENO AND CLINICAL CHARACTERISTICS OF ASTHMA AND ALLERGIC DISORDERS?

Abstract

<h3>Introduction</h3> Fractional exhaled nitric oxide (FeNO) is an adjunctive tool for asthma management. It is also elevated in atopic patients without asthma. We sought to evaluate whether race modifies the association of FeNO with indicators of allergy and asthma. <h3>Methods</h3> Children attending a scheduled 10 year visit as part of the WHEALS (Wayne County Health Environment Allergy and Asthma Longitudinal Study) birth cohort were included, with analysis restricted to participants whose reported race was Black or White. The 10 year visit included determination of allergic rhinitis (AR), atopic dermatitis (AD), asthma, food allergy (FA), spirometry, methacholine challenge, total IgE, eosinophil count, and allergen sensitization. <h3>Results</h3> 459 children (75.4% Black, mean age 10.2 years) had sufficient data for analysis. Children with current asthma, AR, AD, FA, or sensitization to common foods or inhalant allergen had higher FeNO (p <0.001 for each). Black children had higher FeNO levels (p=0.002). Following adjustment for other variables including allergic disorders and atopy, race had no significant association with FeNO (p=0.094). Following adjustment, race was a significant effect modifier only for the association between PC20 and FeNO (p=0.007), where an association of higher FeNO with bronchial hyperresponsiveness was found amongst Black children. <h3>Conclusion</h3> Our data reflects a diverse population with higher levels of FeNO in Black children compared to White children, largely explained by a higher prevalence of allergic disorders and atopy. Although the association between PC20 and FeNO was modified by race, a potential limitation was that we could not conduct a methacholine challenge in all children.