Detrimental effects of beta-blockers in COPD: a concern for nonselective beta-blockers.

INTRODUCTION

beta-Blockers are known to worsen FEV(1) and airway hyperresponsiveness (AHR) in patients with asthma. Both characteristics determine the outcome of COPD, a disease with frequent cardiac comorbidity requiring beta-blocker treatment.

OBJECTIVE

To determine the effects of beta-blockers on AHR (provocative concentration of methacholine causing a 20% fall in FEV(1) [PC(20)]), FEV(1), and response to formoterol in patients with COPD.

DESIGN

A double-blind, placebo-controlled, randomized, cross-over study.

SETTING

An ambulatory, hospital outpatient clinic of pulmonary diseases.

PATIENTS: Patients with mild-to-moderate irreversible COPD and AHR.

INTERVENTION: Fifteen patients received propranolol (80 mg), metoprolol (100 mg), celiprolol (200 mg), or placebo for 4 days, followed by a washout period >/= 3 days. On day 4 of treatment, FEV(1) and PC(20) were assessed. Immediately hereafter, formoterol (12 microg) was administered and FEV(1) was measured for up to 30 min.

RESULTS

PC(20) was significantly lower (p < 0.01) with propranolol and metoprolol treatment (geometric means, 2.06 mg/mL and 2.02 mg/mL, respectively) than with placebo (3.16 mg/mL) or celiprolol (3.41 mg/mL). FEV(1) deteriorated only after propranolol treatment (2.08 +/- 0.31 L) [mean +/- SD] compared with placebo (2.24 +/- 0.37 L). The fast bronchodilating effect of formoterol was hampered by propranolol (mean increase in FEV(1) at 3 min, 6.7 +/- 8.9%) but was unaffected by the other beta-blockers (16.9 +/- 9.8%, 22 +/- 11.6%, and 16.9 +/- 9.0% for placebo, metoprolol, and celiprolol, respectively).

CONCLUSIONS

Pulmonary effects did not occur by celiprolol. Only propranolol reduced FEV(1) and the bronchodilating effect of formoterol. Both metoprolol and propranolol increased AHR. Thus, different classes of beta-blockers have different pulmonary effects. The anticipated beneficial cardiovascular effects of a beta-blocker must be weighted against the putative detrimental pulmonary effects, ie, effect on FEV(1), AHR, and response to additional beta(2)-agonists.