Table 4.
Comparison of clinical characteristics among the three subtypes of COPD with concomitant features of asthma in the general adult population.
| COPD with asthma only (n = 630) | COPD with HBR only (n = 181) | COPD with both asthma and HBR (n = 52) | P- value | |||
|---|---|---|---|---|---|---|
| COPD with asthma only vs. COPD with HBR only | COPD with asthma only vs. COPD with both asthma and HBR | COPD with HBR only vs. COPD with both asthma and HBR | ||||
| Men, % | 341 (62.2%) | 125 (68.6%) | 39 (71.4%) | 0.390 | 0.578 | 0.866 |
| Age, years | 61.8 (1.1) | 47.4 (2.8) | 48.0 (2.2) | <0.001 | <0.001 | 0.883 |
| Ever smoker‡ | 312 (54.4%) | 90 (43.5%) | 29 (43.0%) | 0.165 | 0.438 | 0.968 |
| Eosinophil percentage in peripheral blood (%) | 3.3 (0.4) | 3.0 (0.2) | 3.8 (1.0) | 0.554 | 0.625 | 0.453 |
| Lung function | ||||||
| Post-BD FEV1/FVC, % | 55.2 (1.3) | 66.1 (1.0) | 59.7 (2.2) | <0.001 | 0.059 | 0.038 |
| Post-BD FEV1% pred | 68.2 (2.3) | 96.6 (3.4) | 73.8 (2.8) | <0.001 | 0.033 | <0.001 |
| Short form (SF)-12 scores | ||||||
| PCS scores | 43.3 (0.6) | 52.1 (0.5) | 47.5 (2.1) | <0.001 | 0.046 | 0.035 |
| MCS scores | 50.9 (0.8) | 53.8 (0.9) | 50.2 (2.5) | 0.073 | 0.743 | 0.240 |
| Comorbidities | ||||||
| Allergic rhinitis | 135 (18.7%) | 20 (13.3%) | 15 (29.5%) | 0.361 | 0.532 | 0.378 |
| Hypertension | 103 (15.6%) | 13 (4.1%) | 8 (19.1%) | 0.024 | 0.822 | 0.374 |
| Coronary heart disease | 48 (6.3%) | 5 (1.1%) | 2 (1.0%) | 0.002 | 0.010 | 0.939 |
| Diabetes | 25 (4.6%) | 4 (1.8%) | 2 (1.3%) | 0.350 | 0.255 | 0.729 |
| Medication use | ||||||
| Inhaled corticosteroid | 63 (11.6%) | 3 (1.6%) | 9 (11.5%) | 0.016 | 0.984 | 0.226 |
| Inhaled bronchodilator | 102 (15.7%) | 3 (8.7%) | 17 (21.2%) | 0.105 | 0.693 | 0.406 |
| Aminophylline | 125 (20.7%) | 2 (4.7%) | 14 (31.8%) | 0.008 | 0.288 | 0.016 |
| Systemic corticosteroid | 62 (11.9%) | 2 (4.7%) | 7 (2.2%) | 0.118 | <0.001 | 0.592 |
| Exacerbation of respiratory symptoms in the last 12 months | ||||||
| Emergency, % | 162 (24.7%) | 3 (0.1%) | 16 (43.1%) | <0.001 | 0.145 | 0.001 |
| Hospital admission, % | 89 (13.4%) | 1 (0.02%) | 11 (32.4%) | <0.001 | 0.113 | 0.008 |
Values are weighted and shown as number (%) or mean (SE). FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; HBR, highly bronchodilator responsiveness; MCS, mental component summary; PCS, physical component summary.
‡
Ever smoker was defined as having smoked equal to or >100 cigarettes in his/her lifetime.