Insights From Recent Study Redefine Bronchodilator Response in Asthma and COPD

A ground-breaking study recently published in the authoritative American Journal of Respiratory and Critical Care Medicine has shed new light on bronchodilator responsiveness (BDR) among patients diagnosed with asthma, chronic obstructive pulmonary disease (COPD), or both conditions. Bronchodilator responsiveness refers to the degree to which a person's airways widen or dilate in response to the administration of reliever medication that relaxes the muscles around the airways, leading to improved airflow.

The study, conducted as part of the NOVELTY study and led by esteemed experts in respiratory medicine, including Medical Research Institute of New Zealand (MRINZ) director Professor Richard Beasley, analysed data from a large-scale cohort comprising 6,788 participants across 18 countries.

The research aimed to address the ongoing uncertainty surrounding the use of BDR as a key measure to diagnose asthma. Using both 2005 and 2021 European Respiratory Society/American Thoracic Society criteria for defining BDR, the study assessed BDR prevalence in adults with a clinical diagnosis of asthma, COPD, and both asthma and COPD (asthma/COPD overlap).

The study showed that only 1 in 5 adults with a clinical diagnosis of asthma had a positive BDR test, and that there were similar proportions with a positive BDR test in those with COPD or asthma/COPD overlap. The study's findings cast serious doubt on the utility of BDR as a primary diagnostic tool for asthma.

Patients with a positive BDR test were more likely to have lower lung function, a higher burden of respiratory symptoms, more frequent hospital admissions, and a greater reliance on specific treatments like triple therapy, oral corticosteroids, or biologics. These findings suggest that BDR could be viewed as a treatable characteristic in managing chronic airway diseases.

Professor Beasley, states "Our findings challenge conventional views on the role of BDR in diagnosing asthma and COPD. By examining a large cohort across multiple countries, we’ve provided valuable insights that could influence clinical practice and research strategies in respiratory medicine."

Read the full publication, here.
For a commentary of the study's findings, the aligned editorial can be accessed here: