Mean (SE) baseline demographic data for the 20 subjects with COPD studied
| All (n=20) | NEP=0 (n=9) | NEP=1 (n=4) | NEP=2 (n=7) | |
| Age (years) | 69.9 (1.5) | 61.4 (7.4) | 67.0 (2.0) | 73.9 (1.9) |
| M:F | 15:5 | 7:2 | 4:0 | 4:3 |
| BMI (kg/m2) | 24.7 (2.5) | 25.5 (1.1) | 21.6 (1.1) | 25.4 (1.8) |
| FEV1 (l) | 0.78 (0.05) | 0.96 (0.06) | 0.61 (0.1)1-150 | 0.65 (0.06)1-150 |
| FEV1 (% predicted) | 29.6 (2.3) | 34.2 (2.4) | 20.5 (2.51-150) | 28.9 (4.8) |
| FVC (l) | 2.26 (0.13) | 2.62 (0.19) | 1.98 (0.18) | 1.95 (0.19)1-150 |
| FVC (% predicted) | 64.6 (3.2) | 71.4 (4.0) | 51.3 (4.1)1-150 | 63.4 (5.7) |
| FEV1/FVC (%) | 35.5 (2.2) | 37.6 (2.8) | 30.8 (3.3) | 35.4 (5.1) |
| IC (l) | 1.65 (0.09) | 1.9 (0.2) | 1.5 (0.1) | 1.4 (0.1)1-150 |
| SVC (l) | 2.65 (0.16) | 3.0 (0.2) | 2.5 (0.1) | 2.3 (0.3)1-150 |
| TLC (l) | 7.48 (0.34) | 7.5 (0.5) | 8.5 (0.9) | 6.9 (0.6) |
| Pao 2 (kPa) | 8.75 (0.26) | 9.3 (0.4) | 8.3 (0.3) | 8.3 (0.4) |
| Paco 2(kPa) | 5.52 (0.17) | 5.3 (0.2) | 5.6 (0.4) | 5.8 (0.3) |
| SGRQ (%) | 62.7 (3.3) | 62.7 (5.2) | 64.7 (7.9) | 61.6 (5.9) |
BMI = body mass index; FEV1 = forced expiratory volume in one second; FVC = forced vital capacity; IC = inspiratory capacity; SVC = slow vital capacity; RLC = total lung capacity; Pao 2, Paco 2 = arterial oxygen and carbon dioxide tensions; SGRQ = St George's Respiratory Questionnaire; NEP = negative expiratory pressure; 0 = no flow limitation; 1 = partial flow limitation; 2 = complete flow limitation.
↵1-150 p<0.05.