Table 2.
Participant demographics and clinical characteristics
| All patients | IPAH preserved DLCO | IPAH low DLCO (lung phenotype) | CPFE | Emphysema | |
|---|---|---|---|---|---|
| Number | 22 | 5 | 5 | 7 | 5 |
| Age at study, years | 65 (57–71) | 55 (43–59) | 65 (61–72) | 71 (63–79) | 66 (62–70) |
| Sex, male, % | 50 | 60 | 40 | 71 | 20 |
| DLCO, % pred. | 33 (28–40) | 72 (66–82) | 29 (27–31) | 33 (24–38) | 29 (19–36) |
| FEV1, % pred. | 73 (63–94) | 94 (87–94) | 74 (71–92) | 81 (66–94) | 39 (23–47) |
| FVC, % pred. | 94 (79–104) | 89 (88–110) | 98 (93–102) | 80 (79–103) | 71 (70–102) |
| TLC, % pred. | 100 (84–107) | 89 (83–102) | 100 (93–105) | 86 (67–103) | 113 (106–127) |
| RV, % pred. | 106 (85–137) | 86 (85–98) | 121 (88–131) | 96 (61–132) | 173 (156–213) |
| Body mass index, kg/m2 | 26 (24–29) | 25 (21–28) | 27 (26–34) | 27 (25–29) | 22 (21–26) |
| World Health Organization functional class | |||||
| I, n (%) | 2 (12) | 2 (40) | 0 (0) | 0 (0) | / |
| II, n (%) | 4 (24) | 2 (40) | 1 (20) | 1 (14) | / |
| III, n (%) | 10 (59) | 1 (20) | 3 (60) | 6 (86) | / |
| IV, n (%) | 1 (6) | 0 (0) | 1 (20) | 0 (0) | / |
| 6-min walk distance, m | 346 (251–387) | 558 (484–546) | 252 (177–335) | 353 (250–373) | / |
| N-terminal pro-B-type natriuretic peptide, ng/L | 279 (69–1576) | 60 (40–141) | 306 (132–2675) | 1212 (643–2786) | / |
| Haemoglobin, g/dL | 15.5 (14.3–16.9) | 15.4 (14.4–17.0) | 15.8 (13.6–16.7) | 15.2 (14.5–16.5) | 15.6 (14.9–17.4) |
| Arterial partial pressure of oxygen, mmHg | 61 (54–72) | 77 (65–79) | 57 (54–62) | 58 (53–62) | 60 (55–68) |
| Partial pressure of carbon dioxide, mmHg | 36 (34–39) | 34 (33–39) | 35 (32–40) | 34 (33–36) | 39 (35–42) |
| Oxygen saturation, % | 92 (90–95) | 96 (95–97) | 91 (88–93) | 91 (88–92) | 92 (92–95) |
| Oxygen supplementation, n (%) | 13 (59) | 0 (0) | 4 (80) | 5 (71) | 4 (80) |
| Smoking status, n (%) | |||||
| Active | 3 (14) | 0 (0) | 1 (20) | 2 (29) | 0 (0) |
| Former | 15 (68) | 2 (40) | 3 (60) | 5 (71) | 5 (100) |
| Never | 4 (18) | 3 (60) | 1 (20) | 0 (0) | 0 (0) |
| Pack years | 42 (5–50) | 0 (0–3) | 30 (23–44) | 50 (45–65) | 40 (13–49) |
| Haemodynamics | |||||
| Right atrial pressure, mmHg | 10 (7–12) | 8 (5–9) | 10 (7–12) | 12 (8–13) | / |
| Mean pulmonary arterial pressure, mmHg | 47 (40–54) | 53 (42–59) | 44 (43–48) | 47 (36–54) | / |
| Pulmonary arterial wedge pressure, mmHg | 11 (8–14) | 9 (8–11) | 14 (10–15) | 11 (6–15) | / |
| Cardiac index, L/min/m2 | 2.2 (2.0–2.4) | 1.8 (1.6–1.9) | 2.3 (2.2–2.6) | 2.2 (2.0–2.4) | / |
| Pulmonary vascular resistance, Wood units | 8 (6–13) | 14 (8–16) | 7 (7–8) | 9 (5–11) | / |
| Mixed venous oxygen saturation, % | 63 (57–67) | 67 (56–68) | 60 (58–66) | 54 (42–66) | / |
Values describing a distribution are shown as median (interquartile range)
CPFE combined pulmonary fibrosis and emphysema, DLCO diffusion capacity of the lung for carbon monoxide, FEV1 forced expiratory volume in 1 s, FVC forced vital capacity, IPAH idiopathic pulmonary arterial hypertension, RV residual volume, TLC total lung capacity