The response to bronchodilators is often used to distinguish chronic obstructive pulmonary disease (COPD) and bronchial asthma (BA). Numerous studies have shown that many patients with COPD exhibit significant bronchodilator response while some patients with BA may not. Our study compares the bronchodialator response in patients with COPD and BA.
Retrospective analysis of PFT’s in patients referred with diagnosis of COPD and BA was done. Positive bronchodialator response using ATS criteria were noted in both groups. The patients were further stratified into those under the age of 55 and those over 55. The data was analyzed using independent t-test for the mean and chi square test for any variables with percentage.
78 patients with COPD and 76 patients with BA were identified. In the group younger than 55 years, there were 6 patients with COPD and 47 patients with BA. 20 patients with COPD had significant bronchodilator response (25.6%), and 34 patients with BA had significant bronchodilator response (44.7%). The overall difference in bronchodilator response between the two groups was statistically significantly (p=0.01). In the group younger than 55, 50% (n=3) of patients with COPD had significant bronchodilator response versus 42.6% (n=20) of patient with BA. For the age above 55, 23.6% (n=17) of patient with COPD had significant bronchodilator response versus 48.3% (n=14) of patient with BA and the difference in bronchodilator response for this age group was statistically significant (p=0.01).
Even though patients with BA were more likely to have bronchodilator response a significant number of patients with COPD, exhibit the same. Bronchodilator response was observed in the older cohort of COPD patients as well.
Bronchodialator response cannot reliably distinguish between BA and COPD.
G. Gandev, None.