All patients | Patients with no exacerbations over year 1 | Patients with ≥1 exacerbation over year 1 | p-value# | |
Subjects n | 265 | 123 | 142 | |
FEV1 L | 1.49 (0.97–2.31) | 1.66 (1.04–2.78) | 1.41 (0.96–2.06) | 0.008 |
FEV1 % pred | 46.6 (33.0–74.9) | 52.6 (35.2–94.8) | 43.0 (31.6–65.7) | 0.014 |
VC L | 4.08 (3.19–4.97) | 4.42 (3.58–5.13) | 3.79 (2.95–4.83) | 0.005 |
VC % pred | 104.3 (90.7–118.5) | 107.9 (97.3–122.3) | 102.5 (86.3–113.1) | 0.004 |
RV L | 2.66 (2.02–3.28) | 2.51 (1.90–3.28) | 2.70 (2.19–3.32) | ns |
RV % pred | 127.5 (103.2–162.9) | 123.7 (96.0–150.0) | 132.3 (107.7–170.2) | 0.013 |
TLC L | 7.24 (6.16–8.62) | 7.20 (6.20–8.71) | 7.26 (6.01–8.51) | ns |
TLC % pred | 118.7 (107.7–131.0) | 118.3 (107.1–130.0) | 119.9 (108.0–131.5) | ns |
RV/TLC % | 37.5 (29.9–44.1) | 34.2 (28.3–42.5) | 38.8 (32.9–45.8) | 0.004 |
TL,CO mmol·min−1·kPa−1 | 6.22 (4.57–8.08) | 6.40 (4.66–8.25) | 6.07 (4.42–7.93) | ns |
TL,CO % pred | 66.0 (50.0–82.0) | 68.0 (51.0–84.5) | 65.0 (50.0–81.0) | ns |
TL,CO/VA mmol·min−1·kPa−1·L−1 | 1.02 (0.79–1.37) | 1.09 (0.80–1.38) | 1.01 (0.78–1.32) | ns |
TL,CO/VA % pred | 66.2 (52.0–84.0) | 68.1 (53.0–85.1) | 65.1 (52.0–83.0) | ns |
SGRQ | ||||
Total | 49.5 (31.0–64.0) | 42.0 (22.2–57.3) | 56.4 (39.2–70.2) | <0.001 |
Symptoms | 60.7 (38.8–75.0) | 40.3 (20.1–61.6) | 70.8 (59.0–81.7) | <0.001 |
Activity | 66.2 (41.4–87.2) | 57.3 (35.5–79.7) | 73.0 (47.9–92.5) | <0.001 |
Impacts | 36.4 (18.7–52.3) | 28.2 (13.6–46.2) | 40.9 (25.2–55.6) | <0.001 |
SF36 | ||||
Physical | 36.7 (28.3–45.4) | 39.4 (31.2–48.7) | 34.4 (26.2–43.8) | 0.001 |
Mental | 54.8 (47.5–59.2) | 55.4 (48.6–59.2) | 54.2 (46.0–59.3) | ns |
Data are presented as median (interquartile range). ns: nonsignificant; FEV1: forced expiratory volume in one second; % pred: % predicted; VC: vital capacity; RV: residual volume; TLC: total lung capacity; TL,CO: gas transfer of the lung for carbon monoxide; VA: alveolar volume; SGRQ: St George's Respiratory Questionnaire; SF36: Short-Form 36. Statistical comparison used the Mann-Whitney U-test. #: univariant comparison of those with and without exacerbations.