Baseline characteristics of randomised patients
| Treatment | Control | p-value | |
| Subjects n | 61 | 34 | |
| Demographics | |||
| Age years | 65 (58–69) | 64 (58–69) | 0.69 |
| Male | 35 (57) | 21 (62) | 0.68 |
| White# | 58 (95) | 33 (97) | 0.99 |
| BMI kg·m-2 | 25.2 (21.9–27.9) | 25.7 (21.4–28.3) | 0.90 |
| Smoking pack-years | 50 (37–77) | 50 (39–65) | 0.97 |
| Supplemental oxygen | 41 (67) | 25 (74) | 0.52 |
| Lung function¶ | |||
| FEV1 L | 0.78 (0.65–1.02) | 0.90 (0.70–1.06) | 0.274 |
| FEV1 % pred | 29 (23–35) | 30 (27–38) | 0.132 |
| FVC L | 2.39 (1.97–3.02) | 2.52 (2.02–3.18) | 0.630 |
| TLC L | 7.42 (6.18–8.58) | 6.99 (6.16–7.94) | 0.338 |
| TLC % pred | 124 (115–139) | 120 (108–133) | 0.088 |
| RV L | 4.35 (3.73–5.19) | 4.04 (3.70–4.53) | 0.159 |
| RV % pred | 200 (168–231) | 179 (168–215) | 0.140 |
| DLCO mL·min-1·mmHg-1 | 7.90 (6.13–10.36) | 8.06 (7.18–10.91) | 0.378 |
| DLCO % pred | 33 (26–39) | 36 (28–46) | 0.235 |
| Arterial blood gases+ | |||
| PaO2 mmHg | 70 (64–78) | 71 (63–78) | 0.917 |
| PaCO2 mmHg | 41 (37–45) | 41 (37–44) | 0.837 |
| Exercise performance | |||
| 6MWD m | 313 (236–363) | 293 (247–420) | 0.277 |
| CT§ | |||
| Emphysema % | 34.5 (27.8–44.4) | 30.0 (20.6–39.3) | 0.052 |
| Heterogeneity index | 1.45 (1.27–1.72) | 1.60 (1.40–2.06) | 0.035 |
| Questionnaires | |||
| mMRC U | 3.0 (2.0–3.0) | 2.0 (2.0–3.0) | 0.452 |
| SGRQ U | 54 (46–65) | 58 (45–74) | 0.508 |
| Medication use | |||
| Short-acting bronchodilator | 51 (84) | 26 (77) | 0.395 |
| Long-acting bronchodilatorƒ | 48 (79) | 23 (68) | 0.235 |
| Inhaled corticosteroid | 47 (77) | 21 (62) | 0.113 |
| Oral corticosteroid | 9 (15) | 3 (9) | 0.623 |
Data are presented as median (interquartile range) or n (%), unless otherwise stated. BMI: body mass index; FEV1: forced expiratory volume in 1 s; % pred: % predicted; FVC: forced vital capacity; TLC: total lung capacity; RV: residual volume; DLCO: single breath diffusing capacity of the lung for carbon monoxide; PaO2: arterial oxygen tension; PaCO2: arterial carbon dioxide tension; 6MWD: 6-min walking distance; CT: computed tomography; mMRC: modified Medical Research Council dyspnoea scale; SGRQ: St George's Respiratory Questionnaire. #: race was self-reported. ¶: all lung function measures were obtained post-bronchodilator. +: arterial blood gas measurements were performed while patients were breathing ambient air. §: per cent emphysema was defined as the percentage of total lung tissue with a density <-950 HU. Heterogeneity index = [% voxels in the right upper lobe+left upper lobe <-910 HU]/[% voxels in the right lower lobe+left lower lobe <-910 HU] [10], with higher indices indicating more pronounced upper lobe predominant emphysema. ƒ: long-acting bronchodilator includes long-acting β-agonists, long-acting anticholinergics or both.