Clinical characteristics of the study population
| Controls | GOLD | Controls vs COPD | GOLD stage | |||
| (n=32) | 2 (n=40) | 3 (n=30) | 4 (n=31) | p | p | |
| Women/men | 18/14 | 20/20 | 15/15 | 18/13 | 0.84 | 0.53 |
| Age (years) | 63 (7) | 65 (6) | 63 (8) | 63 (6) | 0.61 | 0.16 |
| BMI (kg/m2) | 25 (3) | 25 (4) | 25 (5) | 22 (6) | 0.76 | 0.02 |
| Current smokers, n (%) | 2 (6) | 17 (43) | 5 (17) | 10 (32) | <0.0001 | 0.26 |
| HR (beats/min) | 66 (12) | 81 (17) | 81 (16) | 88 (18) | <0.0001 | 0.22 |
| SBP (mm Hg) | 121 (17) | 144 (21) | 136 (21) | 137 (23) | <0.0001 | 0.20 |
| DBP (mm Hg) | 76 (13) | 70 (12) | 69 (10) | 67 (14) | 0.006 | 0.20 |
| mPAP (mm Hg) | – | 18 (4) | 20 (6) | 25 (6) | – | <0.0001 |
| PAC (mL/mm Hg) | – | 4.0 (1.1) | 4.2 (1.6) | 3.2 (1.4) | – | 0.022 |
| PVR (Wu) | – | 1.8 (0.7) | 2.0 (0.8) | 3.3 (1.4) | – | <0.0001 |
| CI (L/min/m2) | – | 2.9 (0.4) | 2.9 (0.5) | 3.1 (0.6) | – | 0.35 |
| RV EDV (mL) | 107 (22) | 126 (34) | 137 (39) | 121 (27) | 0.001 | 0.67 |
| LV EDV (mL) | 109 (24) | 113 (26) | 115 (31) | 94 (28) | 0.77 | 0.002 |
| RV/LV EDVI | 1.0 (0.1) | 1.1 (0.2) | 1.2 (0.2) | 1.3 (0.3) | <0.0001 | <0.0001 |
| RV wall thickness (mm) | 3.5 (0,5) | 5.2 (0.8) | 5.8 (1) | 6.5 (1.2) | <0.0001 | <0.0001 |
| FEV1 (L) | 3.1 (0.8) | 1.8 (0.6) | 1.2 (0.4) | 0.7 (0.2) | <0.0001 | <0.0001 |
| FEV1/FVC (%) | 76 (4) | 56 (7) | 45 (10) | 40 (10) | <0.0001 | <0.0001 |
| FEV1% predicted | – | 59 (8) | 39 (6) | 26 (7) | – | <0.0001 |
| DLCO % predicted | – | 64 (14) | 53 (17) | 29 (14) | – | <0.0001 |
| Residual volume (L) | 2.6 (0.4) | 4.6 (0.7) | 4.5 (1.2) | 5.6 (1.2) | <0.0001 | <0.0001 |
| Residual volume % pred. | 118 (16) | 161 (32) | 205 (64) | 262 (47) | <0.0001 | <0.0001 |
| TLC (L) | 6.9 (1.3) | 6.9 (1.2) | 7.3 (1.4) | 7.8 (1.6) | 0.39 | 0.02 |
| TLC % predicted | 112 (11) | 117 (15) | 125 (28) | 137 (20) | 0.002 | 0.0002 |
| Residual volume/TLC (%) | 39 (5) | 52 (8) | 61 (11) | 72 (5) | <0.0001 | <0.0001 |
| SaO2 (%) | – | 96 (1) | 96 (1) | 91 (5) | – | <0.0001 |
| PaO2 (kPa) | – | 10.1 (1.0) | 9.7 (1.2) | 7.9 (1.3) | – | <0.0001 |
| PaCO2 (kPa) | – | 5.1 (0.4) | 5.4 (0.6) | 6.0 (0.8) | – | <0.0001 |
Bold values are statistically significant.
BMI, body mass index; COPD, chronic obstructive pulmonary disease; DBP, diastolic blood pressure; DLCO, diffusion capacity for carbon monoxide of the lungs; FEV1/FVC, forced expiratory volume in 1 s/forced vital capacity; GOLD, Global Initiative for Chronic Obstructive Lung Disease; HR, heart rate; LV EDV, left ventricular end-diastolic volume; mPAP, mean pulmonary artery pressure; PAC, pulmonary arterial compliance; PaO2, arterial oxygen tension; PaCO2, arterial carbon dioxide tension; PVR, pulmonary vascular resistance; RV EDV, right ventricular end-diastolic volume; RV/LV EDVI, right ventricle/ left ventricle end-diastolic volume ratio; SBP, systolic blood pressure; SaO2, arterial oxygen saturation; TLC, total lung capacity.