Lower airway flow influences peak nasal inspiratory flow in school-aged children*

Abstract

Background: Rhinitis and asthma frequently coexist. Peak nasal inspiratory flow (PNIF) objectively evaluates nasal obstruction. Lower airway flow’s impact on PNIF has seldom been analysed in children. We aimed to study the associations between PNIF and: (1)forced expiratory volume in one second (FEV1) and peak expiratory flow (PEF) in children with allergic rhinitis and asthma and healthy controls; (2)allergic rhinitis and asthma control subjective evaluation. Methods: Sequential assessments of PNIF before and after nasal decongestion and spirometry with bronchodilation test were performed in 65 children (6-12 years) with allergic rhinitis and asthma, and 24 gender, age-matched healthy controls. The Control of Allergic Rhinitis and Asthma Test in children (CARATkids) was used for control assessment. Associations were investigated by multiple linear regression models. Results: Baseline and decongested PNIF correlated with baseline and post-bronchodilation FEV1 and PEF, observed independently of rhinitis and asthma diagnosis. The best model for PNIF included PEF, age and gender. No association was found between PNIF and CARATkids scores, except for nasal obstruction self-report. Conclusion: In school-aged children, besides age and gender, PEF values should ideally be known to interpret PNIF values. PNIF can be complementary to subjective control assessment in children with allergic rhinitis and asthma.