Cut-off values to evaluate exercise-induced asthma in eucapnic voluntary hyperventilation test for children.

Janne Burman,Maria Maunula,Tom Kuusela,Mika J Mäkelä,Varpu Elenius,Tuomas Jartti,Heikki Lukkarinen,Olli Kesti,Sami Remes,Katri Väätäinen

doi:10.1111/cpf.12647

Abstract

Background and AimThe eucapnic voluntary hyperventilation (EVH) testing is a diagnostic tool for diagnostics of exercise‐induced bronchoconstriction; while the testing has become more common among children, data on the test's feasibility among children remain limited. Our aim was to investigate EVH testing feasibility among children, diagnostic testing cut‐off values, and which factors affect testing outcomes.MethodsWe recruited 134 patients aged 10–16 years with a history of exercise‐induced dyspnoea and 100 healthy control children to undergo 6‐min EVH testing. Testing feasibility was assessed by the children's ability to achieve ≥70% of the target minute ventilation of 30 times forced expiratory volume in 1 s (FEV1). Bronchoconstriction was assessed as a minimum of 8%, 10%, 12%, 15% or 20% fall in FEV1. Patient characteristics were correlated with EVH outcomes.ResultsOverall, 98% of the children reached ≥70%, 88% reached ≥80%, 79% reached ≥90% and 62% reached ≥100% of target ventilation in EVH testing; of children with a history of exercise‐induced dyspnoea, the decline percentages were as follows: 24% (≥8% fall), 17% (≥10% fall), 10% (≥12% fall), 6% (≥15% fall) and 5% (≥20% fall) in FEV1, compared to 11%, 4%, 3%, 1% and 0% among the healthy controls, respectively. Healthy controls and boys performed testing at higher ventilation rates (p < .05).ConclusionEucapnic voluntary hyperventilation testing is feasible among children aged 10–16 years and has diagnostic value in evaluating exercise‐induced dyspnoea among children. A minimum 10% fall in FEV1 is a good diagnostic cut‐off value. Disease status appears to be important covariates.

Highlights

Exercise-induced dyspnoea is a subjective experience of breathing discomfort during exercise (Weatherald, Lougheed, Taille, & Garcia, 2017) and affects around 14% of school-age children (Johansson et al, 2018)
We hypothesized that eucapnic voluntary hyperventilation (EVH) testing would be feasible among children aged 10–16 years and that the test could provoke bronchoconstriction among children who experience exercise-induced dyspnoea
The third aim was to determine whether common patient characteristics, age, sex, current physician-diagnosed asthma, Childhood Asthma Test score (Liu et al, 2007), current atopic eczema, baseline forced expiratory volume in 1 s (FEV1), achieved minute ventilation level (70%–99% vs. ≥100% level) or response to bronchodilator correlated with the EVH outcomes

Summary

| INTRODUCTION

Exercise-induced dyspnoea is a subjective experience of breathing discomfort during exercise (Weatherald, Lougheed, Taille, & Garcia, 2017) and affects around 14% of school-age children (Johansson et al, 2018). Dysfunctional breathing can be defined as alteration in the normal patterns of breathing (Depiazzi & Everard, 2016), and the typical manifestations of DFB are vocal cord dysfunction and hyperventilation The prevalence of the former is 5%–20% (Cichalewski et al, 2015; Johansson et al, 2015; Tilles, 2015), and the latter is 6%–8% among school-age children (de Groot, 2011; Johansson et al, 2015). We aimed to explore the feasibility of EVH testing among children with exercise-induced dyspnoea. We hypothesized that EVH testing would be feasible among children aged 10–16 years and that the test could provoke bronchoconstriction among children who experience exercise-induced dyspnoea. We have investigated whether patient characteristics might influence testing outcomes

| MATERIAL AND METHODS

| Background data

Findings

| DISCUSSION