Oxitropium bromide improves exercise performance in patients with COPD.

Inhaled anticholinergics may be the first-line therapy for stable COPD. However, the effect of inhaled anticholinergic agents on exercise capacity is still controversial. Fourteen patients with stable COPD (age, 64.6 +/- 5.9 years) completed a randomized, double-blind placebo-controlled crossover trial. All the patients were studied by symptom-limited progressive cycle ergometry before and 90 min after the inhalation of either oxitropium bromide, 800 micrograms, or an identical placebo. Spirometry was assessed before and after each exercise test. While FEV1 averaged 0.85 +/- 0.34 L at 90 min after the inhalation of placebo, FEV1 was 1.01 +/- 0.41 L at 90 min after the inhalation of oxitropium, 800 micrograms (significant from placebo, p < 0.001). The maximal workload of 94.0 +/- 25.8 W after oxitropium administration was significantly greater than the 87.6 +/- 24.7 W measured after placebo (p < 0.01). The maximal minute ventilation was 40.2 +/- 12.3 L/min after oxitropium inhalation and 36.8 +/- 10.5 after placebo inhalation (p < 0.05). The differences in maximal oxygen consumption, maximal carbon dioxide production, and maximal heart rate between oxitropium and placebo inhalation also were statistically significant (p < 0.05, p < 0.05, and p < 0.01, respectively). There was a significant correlation between the change in maximal workload and the change in FEV1 before and after inhalation (r = 0.625, p < 0.01). The inhalation of oxitropium bromide, 800 micrograms, can improve the exercise capacity of patients with stable COPD. It is suggested that the effect is due to the bronchodilation induced by this drug.