Demographics and baseline characteristics
| Study 1 | Study 2 | |||
| Indacaterol + tiotropium (n=570) | Tiotropium + placebo (n=561) | Indacaterol + tiotropium (n=572) | Tiotropium + placebo (n=570) | |
| Age (years), mean (SD) | 64.0 (9.07) | 63.4 (9.22) | 63.1 (8.83) | 62.8 (8.98) |
| Sex, men/women, % | 70/30 | 67/33 | 63/37 | 68/32 |
| Race, % | ||||
| Caucasian | 78.2 | 76.8 | 77.8 | 79.3 |
| Black | 1.1 | 3.0 | 3.0 | 1.9 |
| Asian | 5.4 | 4.5 | 16.6 | 16.5 |
| Native American | 0.4 | 1.2 | – | – |
| Other | 14.9 | 14.4 | 2.6 | 2.3 |
| Duration of COPD (years), mean (SD) | 7.1 (6.12) | 6.6 (6.45) | 7.3 (6.48) | 7.1 (6.26) |
| Severity of COPD, n (%)* | ||||
| Moderate† | 47 | 47 | 46 | 46 |
| Severe or very severe | 53 | 53 | 54 | 54 |
| ICS use, yes/no % | 52/48 | 52/48 | 57/43 | 51/49 |
| Ex-smoker/smoker, % | 60/40 | 64/36 | 62/38 | 57/43 |
| Pack-years, mean (SD) | 47.2 (25.86) | 47.2 (26.58) | 46.2 (25.52) | 46.3 (24.64) |
| FEV1 % predicted (post salbutamol) | 48.3 (9.70) | 48.9 (11.46) | 48.6 (9.74) | 48.6 (9.76) |
| FEV1/FVC (post salbutamol) | 46.4 (9.74) | 45.8 (10.00) | 47.0 (10.21) | 47.2 (9.53) |
| FEV1, litres (pre salbutamol), mean (SD) | 1.15 (0.357) | 1.15 (0.384) | 1.14 (0.364) | 1.15 (0.356) |
| FEV1, litres (post-salbutamol), mean (SD) | 1.32 (0.367) | 1.33 (0.418) | 1.29 (0.368) | 1.32 (0.374) |
| FEV1 reversibility‡ (pre/post salbutamol), % | 16.5 (14.48) | 17.3 (17.13) | 16.3 (15.85) | 16.5 (16.27) |
| FEV1, litres (pre ipratropium), mean (SD) | 1.16 (0.367) | 1.17 (0.396) | 1.16 (0.373) | 1.18 (0.373) |
| FEV1, litres (post ipratropium), mean (SD) | 1.36 (0.419) | 1.35 (0.429) | 1.33 (0.402) | 1.35 (0.407) |
| FEV1 reversibility‡ (pre/post ipratropium), % | 18.5 (15.68) | 16.6 (14.10) | 16.4 (15.32) | 16.5 (15.20) |
↵* Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2007. Data missing for one patient in study 2.
↵† Includes one patient (study 1, tiotropium group) with mild severity.
↵‡ At screening, spirometry measurements were taken to assess bronchodilator reversibility, first to a short-acting β2 agonist (FEV1 measured 10–15 min after inhalation of 4 × 100 μg puffs of salbutamol (equivalent to 4 × 90 μg albuterol ex-mouthpiece) compared with pre-bronchodilator value) and, on the next morning, to an anticholinergic (FEV1 increase 1 h after inhalation of 2 × 21 μg ipratropium bromide (equivalent to 2 × 17 μg ipratropium ex-mouthpiece) compared with pre-bronchodilator value).
COPD, chronic obstructive pulmonary disease; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; ICS, inhaled corticosteroid.