Search

Background: Acute bronchodilator responsiveness is an area of discussion in COPD. No information exists regarding this aspect of the disease from an unselected COPD population. We assessed acute bronchodilator responsiveness and factors influencing it in subjects with and without airway obstruction in an epidemiologic sample., Methods: COPD was defined by GOLD criteria (post-bronchodilator FEV(1)/FVC<0.70). In this analysis, subjects with pre-bronchodilator FEV(1)/FVC <0.70 but > or =0.70 post-bronchodilator were considered to have reversible obstruction. Bronchodilator responsiveness after albuterol 200microg was assessed using three definitions: a) FVC and/or FEV(1) increment > or =12% plus > or =200mL over baseline; b) FEV(1)> or =15% increase over baseline; and c) FEV(1) increase > or =10% of predicted value., Results: There were 756 healthy respiratory subjects, 481 subjects with reversible obstruction and 759 COPD subjects. Depending on the criterion used the proportion of person with acute bronchodilator responsiveness ranged between 15.0-28.2% in COPD, 11.4-21.6% in reversible obstructed and 2.7-7.2% in respiratory healthy. FEV(1) changes were lower (110.6+/-7.40 vs. 164.7+/-11.8mL) and FVC higher (146.5+/-14.2mL vs. -131.0+/-19.6mL) in COPD subjects compared with reversible obstructed. Substantial overlap in FEV(1) and FVC changes was observed among the groups. Acute bronchodilator responsiveness in COPD persons was associated with less obstruction and never smoking., Conclusions: Over two-thirds of persons with COPD did not demonstrate acute bronchodilator responsiveness. The overall response was small and less than that considered as significant by ATS criteria. The overlap in FEV(1) and FVC changes after bronchodilator among the groups makes it difficult to determine a threshold for separating them., (Copyright 2009 Elsevier Ltd. All rights reserved.)

Background: There is scanty information regarding respiratory medication prescription pattern in Latin America. We examined the use of bronchodilators and corticosteroids in a population-based study conducted in five Latin American cities., Methods: Medication use was derived from questions regarding the use of medication "to help breathing" within the previous 12 months, type of medicine, and frequency of use. To minimize the possibility of overdiagnosis, we used postbronchodilator FEV(1)/FVC<0.70 plus FEV(1)<80% as the definition of obstruction., Results: Interviews were completed in 5571 subjects from 6711 eligible individuals, and spirometry was performed in 5314 subjects. There were 360 (6.5%) treated subjects and 5211 not treated. Treated subjects were more likely to be older, women, unemployed, have higher tobacco consumption, higher body mass index, higher FEV(1) reversibility and airway obstruction. They were also more likely to report prior spirometry, prior diagnosis of COPD, asthma or tuberculosis, and more respiratory symptoms. Over half of treated subjects had neither obstruction nor FEV(1) reversibility, and approximately 30% reported no prior diagnosis of asthma or COPD. Prior respiratory diagnoses and wheezing were more strongly associated with treatment than objective measures of airway obstruction., Conclusions: The use of bronchodilators and/or corticosteroids is common in the general population aged 40 years or older, with over one-half of treated subjects using them without being obstructed.