title: Comparison of efficacy of long-acting bronchodilators in emphysema dominant and emphysema nondominant chronic obstructive pulmonary disease.
abstract: BACKGROUND
  The purpose of this study was to clarify the association between morphological phenotypes according to the predominance of emphysema and efficacy of long-acting muscarinic antagonist and β(2) agonist bronchodilators in patients with chronic obstructive pulmonary disease (COPD).
  
  
  METHODS
  Seventy-two patients with stable COPD treated with tiotropium (n = 41) or salmeterol (n = 31) were evaluated for pulmonary function, dynamic hyperinflation following metronome-paced incremental hyperventilation, six-minute walking distance, and St George's Respiratory Questionnaire (SGRQ) before and 2-3 months following treatment with tiotropium or salmeterol. They were then visually divided into an emphysema dominant phenotype (n = 25 in the tiotropium-treated group and n = 22 in the salmeterol-treated group) and an emphysema nondominant phenotype on high-resolution computed tomography, and the efficacy of the two drugs in each phenotype was retrospectively analyzed.
  
  
  RESULTS
  Tiotropium significantly improved airflow limitation, oxygenation, and respiratory impedance in both the emphysema dominant and emphysema nondominant phenotypes, and improved dynamic hyperinflation, exercise capacity, and SGRQ in the emphysema dominant phenotype but not in the emphysema nondominant phenotype. Salmeterol significantly improved total score for SGRQ in the emphysema phenotype, but no significant effects on other parameters were found for either of the phenotypes.
  
  
  CONCLUSIONS
  These findings suggest that tiotropium is more effective than salmeterol for airflow limitation regardless of emphysema dominance, and also can improve dynamic hyperinflation in the emphysema dominant phenotype, which results in further improvement of exercise capacity and health-related quality of life.
authors.affiliation: Department of Biomedical Laboratory Sciences, Shinshu University School of Medicine, Matsumoto, Nagano, Japan. keisaku@shinshu-u.ac.jp
authors.forename: Keisaku
authors.initials: K
authors.lastname: Fujimoto
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Kitaguchi
authors.forename: Shintaro
authors.initials: S
authors.lastname: Kanda
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Urushihata
authors.forename: Masayuki
authors.initials: M
authors.lastname: Hanaoka
authors.forename: Keishi
authors.initials: K
authors.lastname: Kubo
mesh_terms: D058666:Adrenergic beta-2 Receptor Agonists / Q000627:therapeutic use*; D000368:Aged; D000420:Albuterol / Q000031:analogs & derivatives* / Q000627:therapeutic use; D001993:Bronchodilator Agents / Q000627:therapeutic use*; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D006801:Humans; D007564:Japan; D008168:Lung / Q000187:drug effects* / Q000503:physiopathology; D008297:Male; D018727:Muscarinic Antagonists / Q000627:therapeutic use*; D010641:Phenotype; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D011656:Pulmonary Emphysema / Q000175:diagnosis / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D011788:Quality of Life; D020127:Recovery of Function; D012129:Respiratory Function Tests; D012189:Retrospective Studies; D000068299:Salmeterol Xinafoate; D012602:Scopolamine Derivatives / Q000627:therapeutic use*; D012720:Severity of Illness Index; D013997:Time Factors; D000069447:Tiotropium Bromide; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D058666:Adrenergic beta-2 Receptor Agonists; D001993:Bronchodilator Agents; D018727:Muscarinic Antagonists; D012602:Scopolamine Derivatives; D000068299:Salmeterol Xinafoate; D000420:Albuterol; D000069447:Tiotropium Bromide