Comparison of pulmonary function in patients with COPD, asthma-COPD overlap syndrome, and asthma with airflow limitation

摘要

Background: This study was conducted in order to investigate the differences in the respiratory physiology of patients with chronic obstructive pulmonary disease (COPD), asthma-COPD overlap syndrome (ACOS), and asthma with airflow limitation (asthma FL+). Methods: The medical records for a series of all stable patients with persistent airflow limitation due to COPD, ACOS, or asthma were retrospectively reviewed and divided into the COPD group (n=118), the ACOS group (n=32), and the asthma FL+ group (n=27). All the patients underwent chest high-resolution computed tomography (HRCT) and pulmonary function tests, including respiratory impedance. Results: The low attenuation area score on chest HRCT was significantly higher in the COPD group than in the ACOS group (9.52±0.76 vs 5.09±1.16, P + group than in the COPD group (55.6% vs 25.0%, P 1) and peak expiratory flow rate were significantly higher in the asthma FL+ group than in the ACOS group (76.28%±2.54% predicted vs 63.43%±3.22% predicted, P + group than in the COPD group (112.05%±4.34% predicted vs 137.38%±3.43% predicted, P 1 in response to short-acting ?₂-agonists was significantly greater in the ACOS group than in the COPD group (229±29?mL vs 72±10?mL, P + group (229±29?mL vs 153±21?mL, P + group than in the COPD group at the whole-breath (4.29±0.30?cmH₂O/L/s vs 3.41±0.14?cmH₂O/L/s, P 2O/L/s vs 2.68±0.10?cmH₂O/L/s, P +, they may have distinct characteristics of the respiratory physiology and different responsiveness to bronchodilators.