Table 2.
Comparison of baseline characteristics according to symptom variability
| Parameter (N=407) | Consistent group (n=137) | Variable group (n=270) |
P-value |
|---|---|---|---|
| Age, years | 66.9±8.0 | 67.3±7.5 | 0.545 |
| Male | 136 (99.3) | 262 (97.0) | 0.148 |
| Smoking amount, pack-year | 46.0±24.2 | 46.5±25.8 | 0.857 |
| Current smoker (n=394) | 42 (32.8) | 73 (27.4) | 0.272 |
| BMI, kg/m2 | 23.0±3.1 | 23.0±3.3 | 0.914 |
| Family history of BA (n=369) | 22 (17.7) | 40 (16.3) | 0.731 |
| FEV1 (% predicted)* | 60.2±15.7 | 55.9±18.3 | 0.019 |
| 6MWD, m (n=384) | 421.6±86.5 | 421.1±84.5 | 0.963 |
| Charlson’s comorbidity score | 1.4±0.8 | 1.2±0.5 | 0.186 |
| Blood eosinophil count (/mm3, n=355) | 281.8±240.9 | 278.6±359.9 | 0.932 |
| mMRC, initial* | 1.3±0.8 | 1.6±1.0 | 0.001 |
| SD of mMRC during 1 year* | 0±0 | 0.7±0.3 | <0.001 |
| SGRQ (n=391)* | 27.3±16.5 | 33.0±17.9 | 0.002 |
| SGRQ decline (n=337) | −0.1±1.4 | −0.3±1.3 | 0.429 |
| FEV1 decline (mL/year, n=337) | −25.9±26.1 | −23.7±24.4 | 0.456 |
Notes: Data are presented as n (%) or mean ± SD. *Indicated P-value <0.05.
Abbreviations: SD, standard deviation; BMI, body mass index; BA, bronchial asthma; FEV1, forced expiratory volume in 1 second; 6MWD, 6 min walk distance; mMRC, modified Medical Research Council; SGRQ, St. George’s Respiratory Questionnaire.