Baseline characteristics of patients with chronic obstructive pulmonary disease (COPD) and matched controls
| Study 1 | Study 2 | ||
| Controls | COPD | COPD | |
| N | 16 | 18 | 12 |
| Age, years | 63 (6) | 65 (5) | 68 (12) |
| Male, n (%) | 16 (100) | 18 (100) | 5 (42) |
| Body mass index, kg/m2 | 28 (4) | 26 (4) | 24 (6) |
| Smoking history, pack-years* | 35 (26–48) | 36 (35–51) | 45 (39–68) |
| Current smoking | 0 | 0 | 3 (25) |
| Medications when stable | |||
| Short-acting β agonist | 0 | 17 (94%) | 8 (67%) |
| Long-acting β agonist (LABA) | 0 | 3 (17%) | 7 (58%) |
| Inhaled corticosteroids (ICS) | 0 | 1 (6%) | 8 (67%) |
| Oral corticosteroids | 0 | 0 | 2 (17%) |
| Combined LABA/ICS | 0 | 13 (72%) | 7 (58%) |
| Anticholinergics | 0 | 11 (61%) | 7 (25%) |
| Oxygen therapy | 0 | 0 | 1 (8%) |
| Aspirin | 1 (6%) | 2 (11%) | 1 (8%) |
| Post-bronchodilator pulmonary function | |||
| FEV1, l | 3.4 (0.5) | 1.5 (0.7) | 0.81 (0.3) |
| FVC, l | 4.2 (0.6) | 3.5 (0.6) | 2.0 (0.7) |
| FEV1% predicted | 102 (10) | 48 (20) | 39 (17) |
| FVC% predicted | 100 (11) | 85 (15) | 90 (22) |
| FEV1/FVC ratio | 0.79 (0.05) | 0.42 (0.13) | 0.42 (0.12) |
Values are mean (SD) or n (%) unless indicated otherwise.
* Median (IQR).
FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity.