Table 1.
Baseline characteristics of the subjects
| Parameter (N=407) | Mean ± SD, n (%) |
|---|---|
| Age, years | 67.2±7.6 |
| Male | 398 (97.8) |
| Smoking amount, pack-year | 46.3±25.2 |
| Current smoker (n=394) | 115 (29.2) |
| BMI, kg/m2 | 23.0±3.2 |
| Family history of BA (n=369) | 62 (16.8) |
| FEV1 (% predicted) | 57.4±17.5 |
| 6MWD, m (n=384) | 421.3±85.1 |
| Charlson’s comorbidity score | 1.3±0.6 |
| Blood eosinophil count (/mm3, n=355) | 279.6±326.7 |
| mMRC, initial | 1.5±1.0 |
| SD of mMRC during 1 year | 0.5±0.4 |
| SD of mMRC during 1 year =0 (Consistent group) | 137 (33.7) |
| SD of mMRC during 1 year >0 (Variable group) | 270 (66.3) |
| SGRQ (n=391) | 31.2±17.6 |
| SGRQ decline (n=337) | −0.2±1.3 |
| FEV1 decline (mL/year, n=337) | −24.3±24.9 |
Notes: Data are presented as n (%) or mean ± SD.
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.