Table 2 Clinical and pulmonary functional characteristic of subjects
|  | COPD quitting smoking ≤ 5 years (N = 72) | COPD quitting smoking > 5 years (N = 53) | P value |
|---|---|---|---|
Oxygenation index, mmHg | 222.5 ± 42.1 | 253.1 ± 36.8 | 0.000 |
PaCO2, mmHg | 73.7 ± 11.8 | 61.5 ± 10.3 | 0.000 |
SPAP, mmHg | 50.0 ± 9.5 | 42.3 ± 8.4 | 0.000 |
FEV1, L | 1.1 ± 0.4 | 1.6 ± 0.6 | 0.000 |
FEV1% | 40.7 ± 16.1 | 57.5 ± 16.8 | 0.000 |
RV/TLC, % | 57.0 ± 10.9 | 51.7 ± 7.8 | 0.003 |
DLCO, mmol/min/Kpa | 6.1 ± 2.2 | 6.8 ± 1.7 | 0.105 |
DLCO/VA, mmol/min/Kpa/L | 1.1 ± 0.3 | 1.2 ± 0.2 | 0.148 |
AE number per year | 2.7 ± 1.0 | 1.9 ± 1.0 | 0.000 |
Antibiotic time, day | 9.6 ± 1.7 | 8.7 ± 1.1 | 0.002 |
ICS + LABA use, N (%) | 61 (84.7) | 34 (64.2) | 0.011 |
SABA use, N (%) | 30 (41.7) | 19 (35.8) | 0.580 |
SABA time, day | 4.1 ± 5.0 | 3.3 ± 4.5 | 0.318 |
Dose of systemic glucocorticoids, mg, equivalent dose of methylprednisolone | 137.8 ± 67.8 | 100.0 ± 78.8 | 0.006 |
NIV time, day | 6.8 ± 4.5 | 1.9 ± 3.8 | 0.000 |