Salmeterol reduces dyspnea and improves lung function in patients with COPD.
OBJECTIVE
To investigate the short-term effects of inhaled salmeterol on the perception of dyspnea and lung function in patients with COPD.


METHODS
Double-blind, crossover, randomized trial comparing inhaled salmeterol and inhaled placebo over 4 h.


METHODS
Pulmonary function laboratory at university medical center.


METHODS
Sixteen patients with symptomatic COPD and at least 200-mL increase in FEV1 after inhalation of two puffs (180 microg) of albuterol.


METHODS
Visit 1 was used for familiarization. At visits 2 and 3 (2 to 3 days apart), patients inhaled either two puffs of salmeterol (42 microg) or placebo.


RESULTS
Lung function and dyspnea were measured at 0.5, 2, and 4 h after inhalation of the study medication. Dyspnea was measured by the -5 to +5 category scale at rest and by the 0 to 10 category-ratio scale while breathing through inspiratory resistances of 5, 15, and 30 cm H20/L/s. Age was 66+/-8 years (mean+/-SD). FEV1 was 0.97+/-0.331 (51+/-13% predicted). There were significantly higher values for FEV1 and FVC (at all time periods) and lower values for functional residual capacity (at all time periods) and residual volume (at 4 h) with salmeterol than with placebo. There were significantly lower dyspnea ratings on the -5 to +5 category scale (p=0.03 at 2 h and p=0.02 at 4 h) and for the mean dyspnea scores during resistive breathing with salmeterol compared with placebo (p=0.002).


CONCLUSIONS
Inhaled salmeterol reduced dyspnea, increased airflow, and reduced hyperinflation over 4 h in patients with symptomatic COPD.
Ramirez-Venegas
A
A
Department of Medicine, Dartmouth Medical School, Lebanon, NH 03756-0001, USA.
Ward
J
J
Lentine
T
T
Mahler
D A
DA
D000280:Administration, Inhalation; D000318:Adrenergic beta-Agonists / Q000008:administration & dosage / Q000627:therapeutic use*; D000368:Aged; D000420:Albuterol / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use; D001993:Bronchodilator Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004417:Dyspnea / Q000188:drug therapy* / Q000503:physiopathology; D006801:Humans; D008173:Lung Diseases, Obstructive / Q000188:drug therapy* / Q000503:physiopathology; D000068299:Salmeterol Xinafoate; D013147:Spirometry; D013997:Time Factors
D000318:Adrenergic beta-Agonists; D001993:Bronchodilator Agents; D000068299:Salmeterol Xinafoate; D000420:Albuterol