Participant demographics at baseline stratified by quintiles of baseline 15th percentile (Perc15) values
| Quintile 1 | Quintile 2 | Quintile 3 | Quintile 4 | Quintile 5 | |
| Emphysema severity (Perc15) | −906.5 (14.2) | −927.3 (3.5) | −937.0 (2.5) | −945.9 (2.6) | −959.2 (9.0) |
| Number of participants | 422 | 420 | 413 | 418 | 412 |
| Age (years) | 58.0 (4.7) | 59.0 (4.7) | 60.4 (5.5) | 60.4 (5.3) | 61.3 (5.8) |
| Height (m) | 1.78 (0.07) | 1.79 (0.06) | 1.79 (0.06) | 1.79 (0.06) | 1.79 (0.06) |
| Weight (kg) | 85.0 (13.01) | 85.7 (12.2) | 84.8 (12.4) | 86.7 (11.9) | 84.3 (11.8) |
| BMI (kg/m2) | 26.9 (3.3) | 27.0 (3.3) | 26.6 (3.3) | 26.9 (3.3) | 26.9 (3.3) |
| Years in study* | 3.0 (2.9–3.1) | 3.0 (2.9–3.1) | 3.0 (2.9–3.1) | 2.9 (2.9–3.1) | 3.0 (2.9–3.1) |
| Pack-years smoking | 40.1 (16.6) | 40.4 (18.9) | 40.3 (18.0) | 40.5 (17.2) | 40.2 (18.1) |
| Current smokers (%) | 78.0 | 67.4 | 49.2 | 43.5 | 34.1 |
| FEV1 (l) | 3.49 (0.62) | 3.46 (0.63) | 3.44 (0.66) | 3.45 (0.78) | 3.21 (0.89) |
| FEV1/FVC (%) | 76.6 (6.8) | 73.6 (7.7) | 73.0 (7.7) | 71.1 (9.0) | 66.16 (11.6) |
| GOLD classification | |||||
| Normal (%) | 83.4 | 71.4 | 69.3 | 63.9 | 43.7 |
| Stage I (%) | 11.4 | 21.4 | 20.4 | 23.9 | 31.3 |
| Stage II (%) | 5.2 | 6.4 | 9.3 | 10.0 | 20.5 |
| Stage III (%) | 0 | 0.7 | 1.0 | 2.2 | 4.3 |
Values are mean (SD) unless otherwise indicated.
* Median (IQR), quintiles are based on the number of scanned cases.
BMI, body mass index; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity.