Table 1. General clinical characteristics of non-smokers, smokers and COPD patients.
| Parameters | Non-smokers | Smokers | COPD |
| Number of subjects | 12 | 12 | 11 |
| M:F ratio | 6∶6 | 6∶6 | 6∶5 |
| Male/Female (%) | (50%/50%) | (50%/50%) | (45%/55%) |
| Age, yr | 61(49–74) | 58.8(45–79) | 64.1(51–73) |
| Smoking, pack years | - | 38.1(9–70) | 52.9(8–120) |
| Smoking status (Current/Ex-smokers) | - | Current smokers (8) | Current smokers (5) |
| - | Ex-smokers (4) | Ex-smokers (6) | |
| FEV1 % predicted | 105 (89–128) | 92 (72–126) | 53 (38–104) |
| ICS; n (%) | - | n = 1 (8.3%) | n = 6 (54.5%) |
M:F: Male to Female ratio; FEV1: Forced Expiratory Volume in one second; ICS: inhaled corticosteroids.