Sample demographics and characteristics
| Reported comorbidity | Ever smokers (N=88) | GOLD 1 (N=63) | GOLD 2 (N=56) |
| Physician diagnosed asthma | 13 | 11 | 25† |
| Myocardial infraction | 5 | 1 | 4 |
| Angina symptoms | 7 | 1 | 2 |
| Hypertension | 23 | 23 | 22 |
| Depression | 2 | 2 | 4 |
| Diabetes | 10 | 4 | 4 |
| Muscular disorders | 38 | 34 | 25 |
| Osteoporosis | 7 | 11 | 10 |
| Demographics | |||
| Age (years) | 65 (0.9) | 69 (1.1) | 65 (1.3) |
| Body mass (kg) | 78 (1.7) | 76 (1.6) | 74 (2.3) |
| Body mass index (kg·m−2) | 27.45 (0.54) | 26.42 (0.52) | 26.57 (0.70) |
| Proportion of women (%) | 39 | 37 | 53 |
| Smoking (pack-years) | 21.06 (19.88) | 20.47 (20.40) | 28.68† (27.02) |
| St. George’s Respiratory Questionnaire | |||
| Total score | 7.89 (0.98) | 9.52 (1.16) | 18.77† (1.89) |
| Symptoms | 14.76 (1.45) | 15.46 (1.82) | 26.73† (2.89) |
| Activity | 10.99 (1.63) | 14.24 (2.02) | 28.43† (3.12) |
| Impacts | 3.96 (0.83) | 4.96 (0.95) | 10.78† (1.70) |
| Pulmonary functions | |||
| FEV1 post-BD (L) | 2.92 (0.08) | 2.68 (0.08) | 1.95† (0.08) |
| FEV1/FVC post-BD (%) | 77.3 (0.49) | 64.27 (0.61) | 58.38† (1.0) |
| VC (L) | 3.89 (0.12) | 4.34 (0.13) | 3.01† (0.12) |
| TLC (L) | 6.44 (0.15) | 7.09 (0.20) | 6.44 (0.20) |
| FRC (% NHANES predicted) | 108 (2.5) | 120 (3.7) | 126* (4.4) |
| RV (% NHANES predicted) | 120.5 (3.0) | 130.5 (4.3) | 147† (5.3) |
| DLCO (mL·min−1·mm Hg−1) | 24.1 (0.69) | 22.9 (0.89) | 21.1* (1.01) |
Values are mean (SEM).
Statistical significance GOLD 2 versus the two other groups.
*p≤0.05.
†p≤0.001.
DLco, diffusion capacity of lung for carbon monoxide; FEV1/FVC post-BD, post-bronchodilation forced expiratory volume in 1 s/forced vital capacity; FEV1 post-BD, post bronchodilation forced expiratory volume in 1 s; GOLD, Global Initiative for Obstructive Lung Disease; NHANES, National Health And Nutrition Examination Survey; RV, residual volume; TLC, total lung capacity FRC; VC, vital capacity.