Characteristics of the study population (n = 1091) and the subgroup identified with airflow obstruction as judged by a chest physician (n = 675).a
| Presence of obstruction according to chest physician (n = 675) | ||||||
|---|---|---|---|---|---|---|
| Total | No | Mild | Moderate | Severec | P-valueb | |
| n | 1091 | 357 | 136 | 112 | 70 | |
| Sex, % male | 49.0 | 42.3 | 49.3 | 60.7 | 71.4 | <0.001 |
| Age, years | 53.4 | 47.5 | 50.2 | 60.9 | 65.8 | <0.001 |
| (16.9) | (16.2) | (16.4) | (13.8) | (11.0) | ||
| FEV1,d litres | 2.52 | 3.07 | 2.60 | 1.96 | 1.33 | <0.001 |
| (0.93) | (0.74) | (0.79) | (0.61) | (0.52) | ||
| FEV1 % | 82.5 | 98.1 | 83.1 | 66.9 | 48.1 | <0.001 |
| predictedd | (21.0) | (14.3) | (13.0) | (11.5) | (17.4) | |
| FVC,d litres | 3.35 | 3.74 | 3.68 | 3.12 | 2.59 | <0.001 |
| (1.10) | (0.93) | (1.15) | (0.93) | (0.92) | ||
| FEV1/FVC,d % | 75.2 | 82.5 | 71.2 | 63.6 | 52.1 | <0.001 |
| (12.6) | (6.8) | (8.9) | (8.8) | (11.8) | ||
↵a Figures are means (SD) unless stated otherwise.
↵b Test for differences between subgroups based on severity of airflow obstruction.
↵c Including very severe obstruction.
↵d Based on first postbronchodilator measurement available in the database for each patient. FEV1 = forced expiratory volume in 1 second; FVC = forced vital capacity.