Demographic and clinical data of the study population (n = 66)
| Parameters | No |
| Clinical parameters* | |
| Age (years) | 57 (12) |
| Gender (F:M) | 28:38 |
| Smoking (pack years) | 27 non-smokers, 31 ex-smokers, 7 current smokers, 1 unknown |
| Time from presentation (months) | 33 (4–264) |
| WHO class | 3 (1–4) |
| Working diagnosis (based on multidisciplinary consensus including lung biopsy when available) | IPF (n = 16) |
| Idiopathic NSIP (n = 6) | |
| CTD-related fibrosis (n = 17) | |
| Sarcoidosis (n = 12) | |
| Other interstitial diseases (n = 15) | |
| Biopsy diagnosis | n = 13 (20%) |
| Right heart catheter* | |
| mPAP (mm Hg) | 33.6 (11.8) |
| mRAP (mm Hg) | 5.9 (4.2) |
| mLAP (mm Hg)† | 10.7 (5.1) |
| PVR (Wood units) | 5.9 (4.3) |
| PVR index (Wood units/m2) | 10.4 (7.1) |
| Cardiac output (l/min) | 4.3 (1.2) |
| Cardiac index (l/min/m2) | 2.3 (0.5) |
| Echocardiography | |
| RVSP (mm Hg, n = 48) | 56 (24–102) |
| PAT (ms, n = 46) | 100 (33–144) |
| Pulmonary function | |
| Tlco % (n = 65) | 29.6 (14.7) |
| Kco % (n = 65) | 52.0 (19.7) |
| TLC % (n = 61) | 72.5 (20.2) |
| FEV1 % (n = 62) | 62.4 (23.3) |
| FVC % (n = 62) | 67.9 (23.1) |
| Pao2 (kPa, n = 61) | 8.4 (2.2) |
| Paco2 (kPa, n = 61) | 5.0 (0.9) |
| CPI (n = 62) | 56.9 (14.6) |
| 6MWT (n = 42) | |
| End Spo2 (%) | 81.4 (8.4) |
| 6MWT distance (m) | 254.6 (128.1) |
*Data expressed as mean (SD) or median (range). n = 66 unless otherwise specified.
†Pulmonary capillary wedge pressure used to calculate PVR in the absence of left ventricular end diastolic pressure (n = 15).
CPI, composite physiological index; CTD, connective tissue disease; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; IPF, idiopathic pulmonary fibrosis; Kco, transfer factor corrected for alveolar volume; mLAP, mean left atrial pressure; mPAP, mean pulmonary artery pressure; mRAP, mean right atrial pressure; 6MWT, six minute walk test; NSIP, non-specific interstitial pneumonia; Paco2, arterial carbon dioxide tension; Pao2, arterial oxygen tension; PAT, pulmonary acceleration time; PVR, pulmonary vascular resistance; RVSP, right ventricular systolic pressure; Spo2, oxygen saturation on pulse oximetry; TLC, total lung capacity; Tlco, transfer factor for carbon monoxide; WHO, World Health Organization.