Prevalence, Diagnostic Utility and Associated Characteristics of Bronchodilator Responsiveness.

BACKGROUND

The prevalence and diagnostic utility of bronchodilator responsiveness (BDR) in a real-life setting is unclear. We explored this uncertainty in patients aged ≥12 years with physician-assigned diagnoses of asthma, asthma and COPD, or COPD in NOVELTY, a prospective cohort study in primary and secondary care in 18 countries.

METHODS

The proportion of patients with a positive BDR test in each diagnostic category was calculated using 2005 (∆FEV1 or ∆FVC ≥12% and ≥200mL) and 2021 (∆FEV1 or ∆FVC >10% predicted) ERS/ATS criteria.

RESULTS

We studied 3,519 patients with physician-assigned diagnosis of asthma, 833 with asthma+COPD, and 2,436 with COPD. The prevalence of BDR was 19.7% (asthma), 29.6% (asthma+COPD) and 24.7% (COPD) using 2005 criteria; 18.1%, 23.3% and 18.0% respectively using 2021 criteria. Using 2021 criteria, in patients diagnosed with asthma, BDR was associated with higher FeNO, lower lung function, higher symptom burden, more frequent hospital admissions, greater use of triple therapy, oral corticosteroids or biologics; in patients diagnosed with COPD, BDR (2021) was associated with lower lung function and higher symptom burden.

CONCLUSIONS

BDR prevalence in patients with chronic airway diseases on treatment ranges from 18-30%, being modestly lower with the 2021 compared with 2005 ERS/ATS criteria, and is associated with lower lung function and greater symptom burden. These observations question the validity of BDR as a key diagnostic tool for asthma managed in clinical practice or as a standard inclusion criterion for clinical trials of asthma, and instead suggest BDR be considered a treatable trait for chronic airways disease.