title: Bronchodilator response in adults with bronchiectasis: correlation with clinical parameters and prognostic implications.
abstract: BACKGROUND
  Bronchial dilation testing is an important tool to assess airway reversibility in adults with bronchiectasis. This study aims to investigate the association of bronchodilator response (BDR) and clinical parameters in bronchiectasis, and the utility of BDR to indicate lung function decline and risks of bronchiectasis exacerbations (BEs).
  
  
  METHODS
  We recruited 129 patients with clinically stable bronchiectasis. Baseline measurements included assessment of sputum inflammation and matrix metalloproteinase-8 and -9, sputum bacterial culture, spirometry, bronchial dilation test (for baseline FEV1 less than 80% predicted only) and chest high-resolution computed tomography (HRCT). Bronchiectasis patients were followed-up for 1 year to determine the incidence of BEs and lung function trajectories. Significant BDR was defined as FEV1 improvement from pre-dose value by at least 200 mL and 12%. Clinical trial registry No.: NCT01761214; URL: www.clinicaltrials.gov.
  
  
  RESULTS
  BDR was negatively correlated with baseline FEV1 percentage predicted, but not blood or sputum eosinophil count. Significant BDR was not associated with greater proportion of never-smokers, poorer past history, greater HRCT scores, poorer diffusing capacity or increased sputum matrix metalloproteinases (all P>0.05). There was a trend towards higher bronchiectasis severity index (BSI) and greater proportion of patients with Pseudomonas aeruginosa isolation or infection. Significant BDR at baseline was linked to poorer spirometry, but not more rapid lung function decline, throughout follow-up. Patients with significant BDR demonstrated non-significantly lower risks of experiencing the first BEs than those without (P=0.09 for log-rank test).
  
  
  CONCLUSIONS
  Significant BDR is associated with poorer lung function compared with non-significant BDR. Whether BDR predicts future risks of BEs needs to be tested in a larger cohort.
authors.affiliation: 1 State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China ; 2 Department of Respiratory and Critical Care Medicine, First Affiliated Hospital of Zhengzhou University, Zhengzhou 450000, China ; 3 Guangzhou First People's Hospital, Guangzhou 510120, China.
authors.forename: Wei-Jie
authors.initials: WJ
authors.lastname: Guan
authors.affiliation: 1 State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China ; 2 Department of Respiratory and Critical Care Medicine, First Affiliated Hospital of Zhengzhou University, Zhengzhou 450000, China ; 3 Guangzhou First People's Hospital, Guangzhou 510120, China.
authors.forename: Yong-Hua
authors.initials: YH
authors.lastname: Gao
authors.affiliation: 1 State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China ; 2 Department of Respiratory and Critical Care Medicine, First Affiliated Hospital of Zhengzhou University, Zhengzhou 450000, China ; 3 Guangzhou First People's Hospital, Guangzhou 510120, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Xu
authors.affiliation: 1 State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China ; 2 Department of Respiratory and Critical Care Medicine, First Affiliated Hospital of Zhengzhou University, Zhengzhou 450000, China ; 3 Guangzhou First People's Hospital, Guangzhou 510120, China.
authors.forename: Hui-Min
authors.initials: HM
authors.lastname: Li
authors.affiliation: 1 State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China ; 2 Department of Respiratory and Critical Care Medicine, First Affiliated Hospital of Zhengzhou University, Zhengzhou 450000, China ; 3 Guangzhou First People's Hospital, Guangzhou 510120, China.
authors.forename: Jing-Jing
authors.initials: JJ
authors.lastname: Yuan
authors.affiliation: 1 State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China ; 2 Department of Respiratory and Critical Care Medicine, First Affiliated Hospital of Zhengzhou University, Zhengzhou 450000, China ; 3 Guangzhou First People's Hospital, Guangzhou 510120, China.
authors.forename: Jin-Ping
authors.initials: JP
authors.lastname: Zheng
authors.affiliation: 1 State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China ; 2 Department of Respiratory and Critical Care Medicine, First Affiliated Hospital of Zhengzhou University, Zhengzhou 450000, China ; 3 Guangzhou First People's Hospital, Guangzhou 510120, China.
authors.forename: Rong-Chang
authors.initials: RC
authors.lastname: Chen
authors.affiliation: 1 State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China ; 2 Department of Respiratory and Critical Care Medicine, First Affiliated Hospital of Zhengzhou University, Zhengzhou 450000, China ; 3 Guangzhou First People's Hospital, Guangzhou 510120, China.
authors.forename: Nan-Shan
authors.initials: NS
authors.lastname: Zhong
keywords: Bronchiectasis; bronchiectasis exacerbation (BE); bronchodilator response (BDR); clinical parameter