It is high time we standardize the interpretation of bronchodilator responsiveness in children

Abstract

It is high time we standardize the interpretation of bronchodilator responsiveness in children Dear Editor, I read with great attention the interesting paper of Berrier et al. 1 aiming at investigating the sensitivity and specificity of the shape indexes of the flow-volume loop to identify asthmatics from healthy children in comparison to "usual" spirometric data. I congratulate the authors for their captivating idea to explore the bronchodilator responsiveness (BDR) of shape indexes in the context of a lung function testing lab. 1 I agree with Berrier et al. 1 that it is high time to overcome the difficulty of interpreting spirometry in children based on a single spirometric datum such as the forced expiratory volume in 1 s (FEV 1 ). However, in the methodology section of the aforementioned paper, 1 three points related to the bronchodilator test caught my attention.The first point concerns the administered dose of short-acting bronchodilator agent (SABA), where the authors opted for two puffs of salbutamol (i.e., 200 µg). This approach is practical but "debatable". Indeed, in clinical practice, the global initiative for asthma (GINA) 2 and the American thoracic as well as the European respiratory societies (ATS/ERS) 3 recommend the administration of at least 400 µg of SABA. Moreover, in children, unlike the 200 µg dose, the 400 µg dose leads to a significantly greater BDR.

In 2023, it is vital to standardize the interpretation of spirometry in children

“…Fourth, Lovine et al 1 reported that BDR was considered significant when >12% (i.e., relative change related to the initial value) or >200 mL (i.e., absolute change from the initial value), without specifying which spirometric datum/data was/were used (e.g., FEV 1 and/or FVC). Currently, there is no clear “consensus” on what constitutes a clinically significant BDR 6,7 . In children, a “clinically significant” BDR is definition‐dependent, and a 2021 mini‐review 6 has largely discussed the following three questions regarding the issue of a “clinically significant” BDR: which spirometric datum/data, expression mode(s), and threshold(s) should be used?…”

“…Currently, there is no clear "consensus" on what constitutes a clinically significant BDR. 6,7 In children, a "clinically significant" BDR is definitiondependent, and a 2021 mini-review 6 has largely discussed the following three questions regarding the issue of a "clinically significant" BDR: | 2187 which spirometric datum/data, expression mode(s), and threshold(s) should be used? The major limitation of the approach applied by Lovine et al 1 is that the absolute and relative changes in FEV 1 and FVC are inversely proportional to baseline spirometric data and are linked to sex and anthropometric data, such as height and age.…”