title: Exercise capacity and ventilatory response during exercise in COPD patients with and without β blockade.
abstract: BACKGROUND
  Although β blockade (BB) in patients with chronic obstructive pulmonary disease (COPD) does not show signs of worsening pulmonary function or respiratory symptoms, the effects on cardiopulmonary exercise testing (CPET) remain unclear. The aim of this study was to determine whether BB affects exercise capacity, gas exchange, and hemodynamic responses in patients with COPD.
  
  
  METHODS
  Twenty-four COPD subjects on BB were matched to 24 COPD subjects without BB according to age, gender, body mass index, and severity of COPD. All subjects underwent resting pulmonary function and symptom-limited CPET.
  
  
  RESULTS
  Comparing COPD patients with and without BB revealed that percent peak oxygen consumption and VE/VCO2 nadir were not significantly different (45 ± 16 vs. 51 ± 23 %, p = 0.30, and 35.1 ± 8.5 vs. 36.2 ± 11.6 %, p = 0.69). Systolic blood pressure and heart rate at peak exercise were significantly decreased in COPD patients with BB (168 ± 16 vs. 185 ± 20 mmHg, and 109 ± 16 vs. 122 ± 14 bpm, respectively, p < 0.05).
  
  
  CONCLUSIONS
  Exercise capacity and gas exchange remain unaffected in patients with COPD in the presence of BB, although heart rate and blood pressure are lower. These findings imply that BB does not adversely affect functional capacity in patients with COPD.
authors.affiliation: Department of Rehabilitation Medicine, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand, wilawan.thi@mahidol.ac.th.
authors.forename: Wilawan
authors.initials: W
authors.lastname: Thirapatarapong
authors.forename: Hilary F
authors.initials: HF
authors.lastname: Armstrong
authors.forename: Matthew N
authors.initials: MN
authors.lastname: Bartels
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000494:pharmacology / Q000627:therapeutic use*; D000368:Aged; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D016022:Case-Control Studies; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D017079:Exercise Tolerance / Q000187:drug effects / Q000502:physiology*; D005260:Female; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology; D006439:Hemodynamics / Q000187:drug effects / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption / Q000187:drug effects / Q000502:physiology; D029424:Pulmonary Disease, Chronic Obstructive / Q000188:drug therapy* / Q000503:physiopathology*; D011659:Pulmonary Gas Exchange / Q000187:drug effects / Q000502:physiology; D012123:Pulmonary Ventilation / Q000187:drug effects / Q000502:physiology*; D012189:Retrospective Studies; D012720:Severity of Illness Index
chemical_list: D000319:Adrenergic beta-Antagonists