Evaluation of bronchodilator response in patients with airway obstruction

Abstract

The aim of this study was to define the most useful index of expressing bronchodilator response and to distinguish between asthma and COPD. A prospective study was carried out of bronchodilator response in 142 asthmatics and 58 COPD patients in a university hospital. Reversibility was expressed as: 1. absolute change (delta abs); 2. % of initial (delta %init); 3. % of predicted (delta %pred) and 4. % of maximum possible response (delta %max). Dependence on forced expirations volume in 1 sec (FEV1) as % of predicted and sensitivity and specificity for diagnosis of asthma were established. A relationship between delta abs and initial FEV1 was not found in asthma (delta abs vs. % initial FEV1. r = 0.07) or COPD (r = 0.02). delta %pred did not show a correlation in asthma (r = 0.10) or COPD (r = 0.06). delta %init was dependent on the baseline value in asthma (r = 0.38, P < or = 0.001) but not in COPD (r = 0.18, P = n.s.). delta max was dependent in both. The combination of best sensitivity and specificity to separate asthma and COPD was obtained with delta abs (70.4 or 70.6%). The worst specificity for asthma diagnosis was obtained with delta %init (50%). The best likelihood ratios were obtained with delta abs and delta %pred and the worst likelihood ratio with delta %init. delta %init is not recommended as an index for differential diagnosis between asthma and COPD; 2) delta %init overscores bronchodilator response in patients with low FEV1. The independence of each bronchodilator response index should be verified in clinical trials for each selected sample.

Genome-Wide Association Study of Short-Acting β2-Agonists. A Novel Genome-Wide Significant Locus on Chromosome 2 near ASB3

“…The primary outcome phenotype was the change in FEV 1 after two or more puffs of albuterol expressed in one of two ways: FEV 1 Although the latter is the definition conventionally applied to define BDR in the clinical setting, the former may be a more stable measure of BDR overall (16). A total of 724 white subjects were available with BDR.…”

Bronchodilator reversibility in Australian adults with chronic obstructive pulmonary disease

“…Results from these large studies have failed to show any beneficial effect on lung function decline, although the heterogeneity of disease in COPD may have been a confounding factor and the indications for ICS in COPD remain uncertain. In particular, there are conflicting data on whether patients with acute BDR truly have a component of asthma, and it has not been conclusively established whether they really do respond to ICS or have a more favourable prognosis 23 …”

Severity Staging of Chronic Obstructive Pulmonary Disease: Differences in Pre- and Post-Bronchodilator Spirometry

“…It could be partially explained by the weak and inverse correlation between pre-BDT FEV 1 and changes in FEV 1 percentage of predicted values after BDT. This association was also demonstrated by Perng, et al,15 but not by Quadrelli, et al17 and Calverley, et al18…”