Characteristics of patients admitted for asthma exacerbations
| Infrequent Exacerbators | Frequent Exacerbators | P Value | ||
|---|---|---|---|---|
| n | 100 | 100 | ||
| Age, years | 46.5 ± 20.9 | 49.0 ± 17.5 | 0.25 | |
| Female (%) | 69.0 | 77.0 | 0.20 | |
| Ethnicity (%) | Caucasian 82.0Asian 15.0Afro-Caribbean 1.0 | Caucasian 83.0Asian 13.0Afro-Caribbean 1.0 | 0.850.681.00 | |
| Exacerbations managed in primary care in the last 12 months | 0.79 ± 1.15 | 1.92 ± 1.83 | <0.001*** | |
| FEV1/FVC (%) | 71.0 ± 13.4 | 70.9 ± 16.8 | 0.96 | |
| Obstructive lung function (%) | 34.5 | 39.1 | 0.60 | |
| FeNO, ppb | 42.3 ± 57.1 | 24.8 ± 13.6 | 0.97 | |
| High FeNO (%) | 27.3 | 12.5 | 0.44 | |
| Blood eosinophils, x109/L | 0.27 ± 0.39 | 0.32 ± 0.41 | 0.45 | |
| Eosinophilia (%) | 19.0 | 21.0 | 0.72 | |
| Blood neutrophils, x109/L | 7.91 ± 3.87 | 7.70 ± 3.11 | 0.87 | |
| Neutrophilia (%) | 45.0 | 49.0 | 0.57 | |
| Total IgE, kU/L | 470.3 ± 870.3 | 378.9 ± 755.1 | 0.18 | |
| High IgE (%) | 68.2 | 52.9 | 0.11 | |
| Patients with CT scan changes (%) | 78.0 | 90.2 | 0.09 | |
| ICS-LABA (%) | 60.6 | 88.9 | <0.001*** | |
| High-dose ICS (%) | 23.2 | 46.5 | <0.001*** | |
| Long-term OCS (%) | 3.03 | 10.1 | 0.04* | |
| OCS courses in past year | 0.99 ± 1.21 | 2.06 ± 2.34 | 0.005** | |
| SABA dispensed in past year | 7.40 ± 7.89 | 10.94 ± 9.39 | 0.01* | |
| SABA overuse (%) | 64.8 | 78.6 | 0.58 | |
| ICS MPR | 0.72 ± 0.44 | 0.72 ± 0.40 | 0.66 | |
| Good ICS adherence (%) | 48.3 | 40.0 | 0.35 | |
| Poor ICS adherence (%) | 36.7 | 30.8 | 0.49 | |
| Past Medical History | ||||
| COPD (%) | 5.10 | 3.03 | 0.46 | |
| GORD (%) | 30.6 | 46.5 | 0.02* | |
| Depression (%) | 29.6 | 32.3 | 0.68 | |
| Ex or current smoker (%) | 64.5 | 69.9 | 0.51 | |
| BMI | 30.9 ± 6.06 | 34.2 ± 9.48 | 0.14 | |
| Obese (%) | 63.4 | 63.6 | 0.98 | |
| Follow-up within 4 weeks (%) | 54.0 | 67.0 | 0.06 | |
Data presented as mean ± standard deviation, unless stated differently.
FEV1/FVC: ratio of Forced Expiratory Volume in 1 second to the Forced Vital Capacity. FeNO: fractional exhaled nitric oxide. ICS: inhaled corticosteroid. LABA: long-acting β2-agonist. OCS: oral corticosteroid. SABA: short-acting β2-agonist. MPR: medication possession ratio. COPD: chronic obstructive pulmonary disease. GORD: gastro-oesophageal reflux disease.
High FeNO defined as FeNO >40. Eosinophilia defined as blood eosinophils ≥0.5x109/L. Neutrophilia defined as blood neutrophils ≥7.2x109/L. High IgE defined as serum IgE ≥81 kU/L. Good ICS adherence defined as ICS MPR ≥0.8. Poor ICS adherence defined as ICS MPR ≤0.5. SABA overuse defined as ≥3 SABA inhalers per year.