Table 2.
Physiological characteristics of the COPD cohort
| Control (n = 16) | COPD (n = 52) | |
|---|---|---|
| Sex (male/female) | 7, 9 | 30, 22 |
| Age, yr | 66 ± 8 | 66 ± 8 |
| Smoking history,a pack-yr | 0 (0, 10) | 44 (30, 60)*** |
| Weight,a kg | 67 (61, 74) | 66 (59, 77) |
| BMI,a kg/m2 | 24.8 (23.5, 26.2) | 23.3 (21.4, 26.2) |
| FFMI,a kg/m2 | 16.1 (15.3, 17.2) | 15.3 (14.5, 16.8) |
| FEV1,a %pred | 107.6 (100.6, 112) | 40.7 (27.2, 48.4)*** |
| RVTLC | 38 ± 6 | 59 ± 8*** |
| TLCO,a %pred | 92.3 (83.0, 98.1) | 45.0 (32.1, 52.4)*** |
| 6-Min walk, m | 621 ± 84 | 387 ± 125*** |
| 6-Min walk, %pred | 126 ± 12 | 76 ± 24*** |
| PV̇o2,a %pred | 99 (88, 111) | 46 (38, 58)*** |
| SGRQ,a | 2 (0, 8) | 54 (45, 61)*** |
| Quadriceps MVC, kg | 34.7 ± 10.6 | 28.2 ± 8.9* |
| Quadriceps MVC, %pred | 78 ± 19 | 63 ± 14** |
| Locomotion time,a min/12 h | 96 (84, 127) | 41 (26, 56)*** |
| Movement time, %12 h | 23 ± 6 | 13 ± 5*** |
Values are means ± SE or median (interquartile range). BMI, body mass index; FFMI, fat free mass index; FEV1, forced expiratory volume in 1 s; RVTLC, ratio of the reserve volume to total lung capacity; TLCO, transfer capacity of the lung for CO; SGRQ, St George’s respiratory questionnaire; MVC, maximal voluntary contraction.
*
P < 0.05.
**
P < 0.01.
***
P < 0.001. Significance determined by Student’s t-test except for variables denoted a, where P values were calculated by Mann Whitney U-test.