Demographic details at referral of all subjects and those classified as therapy resistant asthma (TRA) and non-TRA after evaluation
| All patients (n=73) | TRA (n=34) | Non-TRA (n=39) | p value | |
|---|---|---|---|---|
| FEV1=forced expiratory volume in 1 second; FVC=forced vital capacity; RV=residual volume; TLC=total lung capacity; Tlco=carbon monoxide transfer factor. | ||||
| *Bioequivalence of inhaled steroids was fluticasone = 2 × beclomethasone = 2 × budesonide. | ||||
| †Unscheduled visits include visits to primary care and hospital accident and emergency departments. | ||||
| Data are presented as mean (SE) or absolute values. | ||||
| Age (years) | 42.6 (1.8) | 43.2 (2.2) | 42.0 (2.8) | NS |
| Female (%) | 49 (67%) | 21 (62%) | 28 (72%) | NS |
| Age of asthma diagnosis (years) | 22.0 (2.1) | 19.9 (3.0) | 23.9 (3.0) | NS |
| Period of instability (months) | 53.9 (8.0) | 75.1 (14.9) | 35.5 (6.5) | p<0.05 |
| Asthma duration (years) | 20.6 (1.8) | 23.4 (2.6) | 18.1 (2.4) | NS |
| Smoker | ||||
| Current | 12 | 6 | 6 | NS |
| Ever | 13 | 6 | 7 | NS |
| Atopy (%) | 40 (55%) | 21 (62%) | 19 (49%) | NS |
| Inhaled steroid at referral (μg BDP equivalent)* | 2347 (148) | 2941 (206) | 1828 (173) | p<0.001 |
| Rescue steroid courses in preceding 12 months | 4.3 (0.4) | 5.3 (0.7) | 3.7 (0.4) | p<0.05 |
| Maintenance systemic steroid | 21 | 16 | 5 | p<0.01 |
| Hospital admission in preceding 12 months | 0.85 (0.2) | 1.0 (0.33) | 0.7 (0.2) | NS |
| Unscheduled visits in preceding 12 months† | 5.3 (1.2) | 4.8 (0.9) | 5.7 (2.2) | NS |
| Previous specialist attendance | 43 | 26 | 17 | p<0.01 |
| Pre-bronchodilator FEV1 (l) | 2.1 (0.10) | 1.90 (0.14) | 2.27 (0.15) | NS |
| Pre-bronchodilator FEV1% | 72 (3) | 65 (2) | 79 (2) | p<0.05 |
| FVC% | 83 (5) | 74 (5) | 91 (7) | NS |
| FEV1/FVC ratio% | 69 (2) | 65 (2) | 72 (2) | p<0.05 |
| RV (%) | 127 (5) | 135 (8) | 119 (8) | NS |
| TLC (%) | 108 (2) | 108 (3) | 109 (3) | NS |
| Tlco (%) | 92 (2) | 90 (4) | 95 (3) | NS |