[Immediate bronchodilator response to formoterol in poorly reversible chronic obstructive pulmonary disease].
OBJECTIVE
To evaluate, using pulmonary function tests, the effectiveness of formoterol as a bronchodilator at 30 min after its administration in patients with poorly reversible COPD.


METHODS
A prospective study including 40 COPD patients not responding to the short-acting bronchodilator used in the spirometric test-variation of less than 200 mL and less than 7% of predicted in forced expiratory volume in one second (FEV1). All patients were classified as having stage II, III, or IV COPD (Brazilian Thoracic Society/Global Initiative for Chronic Obstructive Lung Disease) and presented FEV1 < 70% of predicted value. The patients were randomized into two groups of 20, with similar clinical characteristics, receiving, via a dry powder inhaler, either formoterol or a placebo. The pulmonary function testing (plethysmography) was repeated at 30 min after formoterol or placebo administration.


RESULTS
In the formoterol group, the mean values obtained for FEV1, inspiratory capacity, and forced vital capacity were significantly greater than those obtained in the placebo group (p = 0.00065, p = 0.05, and p = 0.017, respectively), whereas that obtained for airway resistance was significantly lower (p = 0.010). Less pronounced differences were observed for residual volume, vital capacity and specific airway conductance, which were lower, higher and higher, respectively, in the formoterol group.


CONCLUSIONS
In COPD patients not responding to the short-acting bronchodilator used in the spirometric test, formoterol promoted significant improvement in lung function at 30 min after of administration. Further studies are required to confirm whether formoterol can also be used as a medication for immediate relief of symptoms in COPD.
Rubin
Adalberto Sperb
AS
Programa de Residência em Pneumologia, Pavilhão Pereira Filho, Santa Casa de Porto Alegre, Porto Alegre, RS, Brasil. arubin@terra.com.br
Souza
Fábio José Fabrício de Barros
FJ
Hetzel
Jorge Lima
JL
Moreira
José da Silva
Jda S
D000280:Administration, Inhalation; D000368:Aged; D000369:Aged, 80 and over; D001993:Bronchodilator Agents / Q000627:therapeutic use*; D004351:Drug Resistance; D004812:Epidemiologic Methods; D004983:Ethanolamines / Q000627:therapeutic use*; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects / Q000502:physiology; D000068759:Formoterol Fumarate; D006801:Humans; D008297:Male; D008875:Middle Aged; D010919:Placebos; D010991:Plethysmography; D029424:Pulmonary Disease, Chronic Obstructive / Q000188:drug therapy* / Q000503:physiopathology; D013147:Spirometry; D013997:Time Factors
D001993:Bronchodilator Agents; D004983:Ethanolamines; D010919:Placebos; D000068759:Formoterol Fumarate