Table 1.
Baseline characteristics.
| Tertile 1 (n = 24) | Tertile 2 (n = 24) | Tertile 3 (n = 23) | ||||
|---|---|---|---|---|---|---|
| Age (years) | 64.9 | ± 7.5 | 59.8 | ± 9.3 | 59.8 | ± 8.2 |
| Gender (% male) | 13 (54.2) | 13 (54.2) | 16 (69.6) | |||
| Race (% Caucasian) | 20 (83.3) | 16 (66.7) | 16 (69.6) | |||
| BMI (kg/m2) | 29.1 | ± 4.6 | 28.4 | ± 4.5 | 26.9 | ± 5.7 |
| Current smoker [n (%)]* | 4 (16.7) | 12 (50.0) | 14 (63.6) | |||
| Pack year history | 45.2 | ± 19.8 | 48.3 | ± 25.7 | 43.5 | ± 20.6 |
| CB classic def [n (%)] | 2 (8.3) | 4 (16.7) | 7 (30.4) | |||
| CB SGRQ def [n (%)] | 5 (22.7) | 8 (34.8) | 12 (52.2) | |||
| FEV1%Pred | 95.9 | ± 20.8 | 84.1 | ± 16.4 | 85.4 | ± 19.6 |
| FEV1/FVC (%pred) | 92.2 | ± 15.5 | 83.8 | ± 14.7 | 84.0 | ± 16.7 |
| No COPD [n(%)] | 15 (62.5) | 7 (29.2) | 10 (43.5) | |||
| COPD [n(%)] | 9 (37.5) | 17 (70.8) | 13 (56.5) | |||
| 6MWD (m) | 477 | ± 92 | 439 | ± 88 | 466 | ± 66 |
| SGRQ score | 16.1 | ± 17.3 | 26.1 | ± 17.6 | 23.7 | ± 19.1 |
| mMRC dyspnea score | 0.30 | ± 0.64 | 0.65 | ± 0.89 | 0.61 | ± 0.72 |
| CAT score | 7.45 | ± 7.58 | 12.52 | ± 8.46 | 11.83 | ± 7.95 |
| Exac hx (exac.pt/year) | 0.08 | ± 0.28 | 0.54 | ± 1.18 | 0.41 | ± 0.80 |
| Sev Exac Hx (exac.pt/year) | 0.04 | ± 0.20 | 0.17 | ± 0.38 | 0.09 | ± 0.43 |
| GCD (cells/mm)† | 4.30 | ± 2.18 | 11.20 | ± 2.00 | 26.06 | ± 10.59 |
| Mucin conc (µg/mL) | 1185 | ± 967 | 2211 | ± 1482 | 2312 | ± 1915 |
BMI body mass index, CB chronic bronchitis, SGRQ Saint George’s Respiratory Questionnaire, FEV1 forced expiratory volume in 1 s, FVC forced vital capacity, 6MWD 6-min walk distance, mMRC modified medical research council, CAT COPD assessment test, Exac Hx exacerbation history, Sev Exac Hx severe exacerbation history, GCD goblet cell density.
*p = 0.004, †p < 0.0001.