Assessment of Bronchodilator Response in Patients with CF and Non-CF Bronchiectasis-A Randomized Controlled Study

Objectives: Although patients with bronchiectasis tend to have obstructive nonreversible lung functions, some have bronchodilator response (BDR), and a relatively large number are treated with bronchodilators. We assessed BDR in patients with cystic fibrosis (CF) and other bronchiectatic diseases and healthy controls (HCs) in a randomized controlled setup. Methods: Patients with cystic fibrosis (CF), primary ciliary dyskinesia (PCD) and non-CF non-PCD bronchiectasis (non-CF/PCD), as well as HCs, were recruited. Participants were randomly assigned to receive salbutamol (four puffs) and then a placebo or a placebo and then salbutamol. BDR was calculated using the American Thoracic Society (ATS)/European Respiratory Society (ERS) standard, defined as the change related to the individual's predicted value (new method) or to the initial value (old method). Results: Sixty-nine patients (CF = 30, PCD = 20, non-CF/PCD = 19) and 20 HCs were included. Patients with CF and PCD (but not non-CF/PCD) had a statistically greater mean response to salbutamol compared with the placebo, (CF-salbutamol first: 2.82 vs. 0.85%, p = 0.01; placebo first: 2.39 vs. -0.27%, p = 0.02; PCD-salbutamol first: 5.32 vs. 1.88%, p = 0.01; placebo first: 2.24 vs. 0.77%, p = 0.05). Few patients had significant BDR (new method, >10%)-CF (0), PCD (2), non-CF/PCD (0) and HCs (2)): using the old method, an additional PCD patient and three non-CF/PCD had significant BDR (>12%). Conclusions: Significant BDR seems to be rare in patients with bronchiectasis. In CF and PCD, the response was greater than the placebo; the clinical significance of this difference and its therapeutic implications, as well as the best method to determine BDR, have yet to be determined.