Evaluation of the clinical impact of the revised Bronchodilator responsiveness of the ATS/ERS 2021 on asthmatic children

Abstract

<b>Introduction:</b> The ATS/ERS 2021 (AE21) proposed a new definition of the bronchodilator (BD) responsiveness (BDR) basing on the increase of the forced expiratory volume in 1 second (FEV 1) over 10% of the predicted value. <b>Objectives:</b> To assess whether the AE21 BDR definition is valid or not in asthmatic children. <b>Methods:</b> We have conducted a retrospective study, involving asthmatic children in the Physiology and functional exploration department of Habib Bourguiba hospital of Sfax. Spirometry was performed before and after BD. Proximal obstructive defect (POD) was defined by FEV1/forced vital capacity (FVC)&lt;Lower limit of normal. Significant BDR was established according three definitions of: the AE21, the ATS/ERS 2005 (AE05) (increase of FEV1 or FVC by 200 ml and 12% of the initial value) and the GINA 2021 (G21) (increase of FEV1 by 12% of the predicted value). For statistical purpose, we have used the SPSS 20. A p&lt;0.05 was significant. <b>Results:</b> Among 200 included children (130 M/70F), 74.5% had a POD. The median age was of 9.5 years. In the all population, the percentage of BDR by AE21 was 36% significantly higher than those of AE05 (35%) and G21 (24.5%) (p&lt;0.05). These percentages were higher among children with POD respectively 45% by AE21, 45% by AE05 and 31% by G21 (P&lt;0.05). The Cohen Kappa test has shown a k value of 0.803, 0.732 and 0.681 respectively between AE21 and AE05, A21 and G21 and finally AE05 and G21. <b>Conclusion:</b> The BDR assessment depends on the scholarly society. The AE21 definition provides a significantly higher BDR rate than AE05 and G21 ones. Prospective randomized studies would help standardize the interpretation of BDR in children.