Is an anticholinergic agent superior to a beta 2-agonist in improving dyspnea and exercise limitation in COPD?

To evaluate the impact of a week-long course of inhaled albuterol compared with ipratropium on expiratory peak flow, exercise performance, and dyspnea in patients with stable COPD.

A double-blind, two-period, crossover evaluation, wherein the subjects inhaled albuterol, two puffs four times a day (qid) for 7 days, or ipratropium, two puffs quid for 7 days, in random sequence.

Outpatients of the Pennsylvania State University Hospital, Lebanon VA Medical Center, and local private office practices.

A sample of 15 subjects with stable COPD with FEV1 < 55% predicted.

Variables measured at baseline (no inhaled bronchodilator) and/or on day 7 of each arm included FEV1 (liters), 12-min walk test distance (meters), "rescue" puffs of metaproterenol needed each week, and dyspnea scoring after walking, on the Borg Category Scale (0 to 10 = maximal). There was no significant difference in distance walked in 12 min (mean of 751.0 +/- 55.5 [+/- SE]) vs 755.7 +/- 61.3 m) or perceived dyspnea (mean 2.7 +/- 0.4 vs 3.3 +/- 0.4) during albuterol or ipratropium use. Seven patients preferred ipratropium, seven preferred albuterol, and one had no preference.

We conclude that the effects of 1 week of albuterol or ipratropium have similar effects on exercise performance and subjective dyspnea in patients with stable COPD.