Table 1.
Baseline characteristics of the study participants
| Entire cohort (n = 133) |
COPD (n = 88) |
Controls (n = 45) |
p value* | |
|---|---|---|---|---|
| Male sex | 111 (83.5%) | 81 (92%) | 30 (66.7%) | < 0.001 |
| Age (years) | 62.5 (9.2) | 65.4 (7.8) | 56.9 (9.2) | < 0.001 |
| BMI (kg/m2) | 27.6 (5) | 27.6 (5) | 27.6 (4.9) | NS |
| Smoking (pack-yr) | 56.4 (25.9) | 62.2 (25) | 45.3 (24.3) | < 0.001 |
| Charlson-age | 3.11 (1.5) | 3.7 (1.2) | 1.8 (1.4) | < 0.001 |
| Exhaled CO (ppm) | 8.5 (9.7) | 6.5 (7.7) | 13.9 (12.4) | 0.015 |
| FVC (%) | 92.7 (17.4) | 92.7 (19) | 92.8 (13.8) | NS |
| FEV1 (%) | 69.1 (23.4) | 58.9 (20.5) | 90 (12.8) | < 0.001 |
| Dyspnea (MRC) | 0.86 (0.67) | 0.97 (0.68) | 0.64 (0.6) | 0.009 |
Data expressed as mean (standard deviation) or absolute (relative) frequencies, as appropriate. *Data were analyzed using Student's t test or the χ2 test, as appropriate.
FVC: Forced vital capacity. FEV1: Forced expiratory volume in 1 second. BMI: body mass index. CO: carbon monoxide. MRC: Medical Research Council scale.