Table 2.
Characteristics of different trajectory groups
| Variable | Trajectory 1: Infrequent exacerbators | Trajectory 2: Nonpersistently frequent exacerbators | Trajectory 3: Persistently frequent exacerbators | Significance (P‐value for Trajectory 3 vs. trajectories 1 and 2) |
|---|---|---|---|---|
| Number of patients (n) | 106 | 53 | 18 | |
| Age (y) | 56 ± 19 | 55 ± 18 | 63 ± 16 | .131 |
| Age of asthma onset (y), | 33 (10‐52) | 36 (10‐46) | 36 (15‐66) | .374 |
| Body mass index (kg/m2) | 24.9 ± 5.5 | 25.8 ± 5.6 | 28.8 ± 5.7 | a.009 |
| Female gender, n (%) | 54 (50.9%) | 29 (54.7%) | 12 (66.7%) | .243 |
| Family history of asthma, n (%) | 22 (20.8%) | 10 (18.9%) | 6 (33.3%) | .196 |
| History of near‐fatal asthma, n (%) | 4 (3.8%) | 3 (5.7%) | 3 (16.7%) | a.033 |
| Current smoker, n (%) | 12 (11.3%) | 3 (5.6%) | 2 (11.1%) | .082 |
| Asthma Control Test score | 20 (17‐22)Mode: 20 | 18 (15‐21)Mode: 18 | 19 (15‐21)Mode: 15 | .517 |
| On omalizumab/systemic steroids/long‐acting anticholinergic | 0 (0.0%) | 0 (0.0%) | 2 (11.1%) | a<.001 |
| Severe exacerbations in 2010 | 0 (0‐1) | 2 (1‐4) | 4 (2‐5) | a<.001 |
| Comorbidities, n (%) | ||||
| Allergic rhinitis | 54 (50.9%) | 30 (56.6%) | 10 (55.6%) | .826 |
| Eczema | 2 (1.9%) | 4 (7.5%) | 2 (11.1%) | .156 |
| Aspirin sensitivity | 7 (6.6%) | 2 (3.8%) | 3 (16.7%) | .078 |
| Reflux disease | 15 (14.2%) | 7 (13.2%) | 7 (38.9%) | a.006 |
| Obstructive sleep apnea | 0 (0.0%) | 3 (5.7%) | 2 (11.1%) | a.025 |
| Anxiety | 2 (1.9%) | 2 (3.8%) | 1 (5.6%) | .461 |
| Depression | 3 (2.8%) | 1 (1.9%) | 3 (16.7%) | a.004 |
| Lung function | ||||
| FEV1% predicted | 68 ± 22 | 73 ± 22 | 74 ± 23 | .508 |
| FVC % predicted | 74 ± 18 | 75 ± 18 | 80 ± 20 | .171 |
| FEV1/FVC ratio (%) | 69 ± 14 | 73 ± 12 | 67 ± 14 | .388 |
| Serum eosinophils | 0.246 ± 0.288 | 0.254 ± 0.515 | 0.194 ± 0.402 | .367 |
| No. of patients | 37 | 37 | 18 | |
| Medication possession ratio | ||||
| 2011 | 0.58 ± 0.33 | 0.57 ± 0.31 | 0.51 ± 0.26 | .420 |
| No. of patients | 93 | 46 | 14 | |
| 2014 | 0.51 ± 0.33 | 0.43 ± 0.32 | 0.60 ± 0.52 | .337 |
| No. of patients | 44 | 24 | 10 | |
Data are presented as mean ± standard deviation, median (interquartile range) or percentages. Serum eosinophils are reported as geometric mean ± standard deviation.
FEV1, forced expiratory volume in one‐second; FVC, forced vital capacity; ICS, inhaled corticosteroids.
P‐values are reported for Student's t‐test, Mann‐Whitney, or Chi‐squared tests.
a
Statistically significant differences (P<.05).