Cardio-selective and non-selective beta-blockers in chronic obstructive pulmonary
disease: effects on bronchodilator response and exercise.
Author(s): Chang CL, Mills GD, McLachlan JD, Karalus NC, Hancox RJ.
Affiliation(s): Respiratory Research Unit, Department of Respiratory Medicine, Waikato Hospital,
Hamilton, New Zealand.
Publication date & source: 2010, Intern Med J. , 40(3):193-200
BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) often have
co-existing cardiovascular disease and may require beta-blocker treatment. There
are limited data on the effects of beta-blockers on the response to inhaled
beta2-agonists and exercise capacity in patients with COPD.
OBJECTIVE: To determine the effects of different doses of cardio-selective and
non-selective beta-blockers on the acute bronchodilator response to beta-agonists
in COPD, and to assess their effects on exercise capacity.
METHODS: A double-blind, randomized, three-way cross-over (metoprolol 95 mg,
propranolol 80 mg, placebo) study with a final open-label high-dose arm
(metoprolol 190 mg). After 1 week of each treatment, the bronchodilator response
to salbutamol was measured after first inducing bronchoconstriction using
methacholine. Exercise capacity was assessed using the incremental shuttle walk
RESULTS: Eleven patients with moderate COPD were recruited. Treatments were
well-tolerated although two did not participate in the high-dose metoprolol
phase. The area under the salbutamol-response curve was lower after propranolol
compared with placebo (P=0.0006). The area under the curve also tended to be
lower after high-dose metoprolol (P=0.076). The per cent recovery of the
methacholine-induced fall was also lower after high-dose metoprolol (P=0.0018).
Low-dose metoprolol did not alter the bronchodilator response. Oxygen saturation
at peak exercise was lower with all beta-blocker treatments (P=0.046).
CONCLUSION: Non-selective beta-blockers and high doses of cardio-selective
beta-blockers may inhibit the bronchodilator response to beta2-agonists in
patients with COPD. Beta-blockers were also associated with lower oxygen
saturation during exercise. The clinical significance of these adverse effects is
uncertain in view of the benefits of beta-blocker treatment for cardiovascular