Table 1.
Baseline characteristics
| Characteristics | No AOa
|
AOa | Kruskal–Wallis test (P-value) | |
|---|---|---|---|---|
| Pre-BD FEV1≥70% | Pre-BD FEV1 <70% | |||
| Subjects, n | 2,076 | 110 | 150 | |
| Age (years), mean (SD) | 60.3 (10.5) | 65.0 (9.4) | 66.5 (8.9) | <0.0001 |
| Male (%) | 41.7 | 45.5 | 68.7 | |
| BMI (kg/m2), mean (SD) | 23.3 (3.4) | 22.8 (2.9) | 22.2 (3.0) | <0.001 |
| Pack-year | <0.0001 | |||
| Mean (SD) | 11.6 (19.7) | 15.6 (21.5) | 31.0 (30.7) | |
| Median (IQR) | 0 (0–19.5) | 0 (0–30.8) | 26.5 (0–47.5) | |
| Smoking status (%) | ||||
| Never | 59.3 | 52.7 | 28.0 | |
| Former | 25.4 | 24.5 | 35.3 | |
| Current | 15.3 | 22.7 | 36.7 | |
| COPD-PS score | <0.001 | |||
| Mean (SD) | 2.4 (1.4) | 2.9 (1.4) | 3.9 (1.7) | |
| Median (IQR) | 2 (2–4) | 2 (2–4) | 4 (2–5) | |
| IPAG questionnaire score, mean (SD) | 16.7 (4.9) | 18.8 (4.0) | 22.0 (5.0) | <0.0001 |
| %FVC, mean (SD) | 100.7 (13.0) | 101.4 (13.6) | 96.4 (16.6) | <0.01 |
| Pre-BD FEV1% predicted, mean (SD) | 95.4 (13.2) | 84.8 (12.2) | 74.6 (16.7) | <0.0001 |
| Post-BD FEV1% predicted, mean (SD) | NA | 91.2 (13.0) | 77.9 (16.7) | <0.0001 |
| Pre-BD FEV1%, mean (SD) | 77.7 (4.6) | 67.6 (2.6) | 62.2 (6.4) | <0.0001 |
| Post-BD FEV1%, mean (SD) | NA | 73.6 (3.6) | 63.2 (6.8) | <0.0001 |
| Reversibility (%) | NA | 29.1 | 18.0 | |
| COPD stage (%) | ||||
| Mild | NA | NA | 46.0 | |
| Moderate | NA | NA | 48.0 | |
| Severe | NA | NA | 5.3 | |
| Very severe | NA | NA | 0.7 | |
Notes:
a
No AO, post-BD FEV1/FVC ≥0.7; AO, post-BD FEV1/FVC <0.7.
Abbreviations: AO, airflow obstruction; BD, bronchodilator; FEV1, forced expiratory volume in 1 second; BMI, body mass index; IQR, interquartile range; COPD-PS, COPD Population Screener; IPAG, International Primary Care Airway Group; FVC, Forced Vital Capacity; NA, not applicable; SD, standard deviation.