RESUMEN
BACKGROUND: Smoking-related chronic obstructive pulmonary disease and chronic asthmatic bronchitis, which are the most important causes of chronic airflow obstruction (CAO), can occur together in a pat,ient and the prognoses of these two diseases are different each other. OBJECTIVE AND METHOD: To estimate the extent of asthmatic component in patients with CAO and to evaluate the role of atopy as a predictable index for reversibility of airflow obstruction, 89 CAO patients who were older than 40 years were examined retrospectively. RESULT: Only 15 patients (16.8%) showed an increase of >15% in FEV20 to inhaled salbutamol (short-term responder). However, 18 out of 32 patients (56.3%), who were not responded significantly to inhaled bronchodilator and performed a follow-up lung function study, showed an increase of ) 15% in FEV20 to anti-asthmatic therapy including corticosteroid for 3-4 weeks (long-term responder). Peripheral blood eosinophil count only was different between short-term responder and short-term nonresponder, and there was no difference in all of the measurements between short-term responder and long-term responder. However, there were significant differences in smoking, wheezing on auscultation, peripheral blood eosinophil counts, serum total IgE levels, and MAST atopy score between long-term responder and long-term nonresponder. The increase in FEV, following shortor long-term therapy was related to peripheral blood eosinophil counts and MAST atopy score, and it was significantly great,er in patients with high eosinophil counts or high atopy score. CONCLUSION: About 2/3 of patients with CAO who were older than 40 years had an asthmatic component ap atopy may be useful to predict good bronchodilator response to anti-asthmatic therapy.