| GOLD A/B | GOLD C/D | |
| n | 2259 | 2903 |
| Age (years), mean ± SD | 64.3 ± 8.6 | 63.8 ± 8.0 |
| Male, n (%) | 1576 (69.8) | 2186 (75.3) |
| Ex-smoker, n (%) | 1348 (59.7) | 1906 (65.7) |
| Post-bronchodilator FEV1 (L), mean ± SD | 1.73 ± 0.44 | 1.1 ± 0.37 |
| Post-bronchodilator FEV1 (% predicted), mean ± SD | 62.9 ± 8.2 | 39.9 ± 11.6 |
| Reversibility (mL), mean ± SD | 193 ± 158 | 154 ± 131 |
| Baseline maintenance medication, n (%) | ||
| ICS | 871 (38.6) | 1575 (54.3) |
| ICS without LABA | 165 (7.3) | 255 (8.8) |
| ICS plus LABA | 706 (31.3) | 1320 (45.5) |
| LABA | 904 (40.0) | 1489 (51.3) |
| LAMA | 768 (34.0) | 1072 (36.9) |
| Xanthines | 153 (6.8) | 363 (12.5) |
SD, standard deviation; FEV1, forced expiratory volume in 1 s; LAMA, long-acting muscarinic antagonist.