Baseline characteristics of patients with COPD and non-COPD subjects
| Characteristics | COPD, n=44 400 | Non-COPD, n=175 545 |
| Age at diagnosis, mean (SD) years | 67.1 (11.4) | 66.8 (11.4) |
| Gender, n (%) | ||
| Male | 23 509 (52.9) | 92 981 (52.9) |
| Female | 20 891 (47.1) | 82 564 (47.1) |
| Townsend quintile, n (%) | ||
| 1 least deprived | 6890 (15.5) | 39 167 (22.3) |
| 2 | 7585 (17.1) | 37 957 (21.6) |
| 3 | 8937 (20.1) | 34 992 (19.9) |
| 4 | 10 297 (23.1) | 32 518 (18.5) |
| 5 most deprived | 9222 (20.7) | 24 787 (14.1) |
| Not recorded | 1472 (3.3) | 6124 (3.5) |
| Most recent smoking status, n (%) | ||
| Never | 4773 (10.7) | 84 184 (47.9) |
| Ex | 21 983 (49.5) | 55 599 (31.7) |
| Current | 16 497 (37.1) | 27 349 (15.6) |
| Not recorded | 1147 (2.5) | 8424 (4.7) |
| Most recent body mass index, n (%) | ||
| ≤20 kg/m2 | 5578 (12.5) | 9541 (5.4) |
| >20 kg/m2 | 36 722 (82.7) | 149 065 (84.8) |
| Not recorded | 2100 (4.7) | 16 939 (9.6) |