Impulse Oscillometry as a Predictor of Asthma Exacerbations in Young Children

Abstract

Background: In a post-hoc analysis of a pediatric asthma study, we identified the predictors of asthma exacerbations (AEs) and related them to forced expiratory volume (FEV₁), the FEV₁/FVC ratio, and bronchial hyperresponsiveness (BHR). Objectives: We sought to detect predictors of AEs in a prospective study that utilizes impulse oscillometry (IOS) and to compare the results to previously determined predictors. Methods: A moderate AE was defined as an increased use of salbutamol during coughing episodes. Pulmonary function and BHR were measured during symptom- and medication-free periods. Additionally, allergen testing and IOS were included. To calculate the sensitivity and specificity of AE detection, a receiver-operating characteristic (ROC) curve was plotted, and accuracy was measured with the area under the ROC curve (AUC). A logistic regression analysis was used to predict the probability of an exacerbation. Results: Seventy-five pediatric patients (4-7 years of age) with intermittent asthma were included. In 69 patients, the following cut-off values demonstrated the best sensitivity and specificity combination for predicting an AE: FEV₁ 103.2% (AUC 0.62), BHR (PD₂₀methacholine) 0.13 mg (AUC 0.61), and, in 54 children, Rrs5 0.78 kPa × l^-1 × s (AUC 0.80). Logistic regression analysis demonstrated that the combination of all parameters predicted the individual risk of AEs with an accuracy of 86%. Conclusions: IOS, a simple method, predicted the probability of AEs in young children. Airway resistance, measured by IOS, was superior to FEV₁ and methacholine testing. The current data suggest that peripheral airway obstruction is present during symptom-free periods and that these children more likely experience AEs.

Input oscillometry and the forced oscillation technique for assessing lung function in preschool children with asthma

“…20 In addition, Robinson has shown that high between-test variability of impedance measurements can be a marker of both asthma severity and poor control.…”

Evaluation of exposures and respiratory health at a coffee roasting and packaging facility.

“…Impulse oscillometry can be useful as an indirect measure of airflow obstruction and helpful in individuals not able to perform forced breathing maneuvers required during the spirometry test. The impulse oscillometry test has been used for many years to measure changes in the airways of children with lung problems such as asthma and cystic fibrosis [Song et al 2008;Komarow et al 2011;Shi et al 2012;Schulze et al 2016]. More recently, impulse oscillometry has been used to investigate lung problems in adults exposed to dust or chemicals, such as World Trade Center emergency responders and soldiers returning from deployment overseas [Oppenheimer et al 2007;Berger et al 2013;Weinstein et al 2016].…”

Evaluation of exposures and respiratory health at a coffee roasting and packaging facility.

“…Impulse oscillometry may be useful as an indirect measure of airflow obstruction and helpful in individuals not able to perform forced breathing maneuvers that are required during the spirometry test. The impulse oscillometry test has been used for many years to measure changes in the airways of children with lung problems such as asthma and cystic fibrosis [Song et al 2008;Komarow et al 2011;Shi et al 2012;Schulze et al 2016]. More recently, impulse oscillometry has been used to investigate lung problems in adults exposed to dust or chemicals, such as World Trade Center emergency responders and soldiers returning from deployment overseas [Oppenheimer et al 2007;Berger et al 2013;Weinstein et al 2016].…”