Table 3. Comparison of characteristics of patients aged ≥19 yrs at diagnosis meeting traditional haemodynamic characteristics of pulmonary arterial hypertension with those with a pulmonary capillary wedge pressure (P_pcw) of 16–18 mmHg

	P_pcw at diagnosis
	≤15 mmHg	16–18 mmHg	p-value
Subjects n	2525	239
Age yrs
At enrolment	53.0±14.0	56.1±14.5	0.001
At diagnosis	50.1±14.4	53.6±14.9	<0.001
Female	2007 (79.5)	174 (72.8)	0.016
Time from diagnosis	24.9 (8.0–50.9)	20.2 (5.5–44.6)	0.038
6MWD m	366±126	339±117	0.004
P̄_ra mmHg	9.3±5.6	12.8±5.6	<0.001
PVRI Wood units·m²	21.1±12.5	19.1±13.0	0.052
Hypertension	980 (40.2)	111 (47.6)	0.023
Obese^#	697 (33.3)	85 (41.9)	0.014
Sleep apnoea	484 (21.0)	85 (39.9)	<0.001
Diabetes overall	293 (12.0)	47 (20.2)	<0.001
Renal insufficiency	109 (4.5)	25 (10.7)	<0.001
Cadiomyopathy dilated	24 (1.0)	4 (1.7)	0.286
Warfarin	1302 (53.4)	105 (45.1)	0.016
Oxygen	982 (40.3)	110 (47.2)	0.036
β-blocker	296 (12.1)	51 (21.9)	<0.001

Data are presented as mean±sd, n (%) or median (interquartile range), unless otherwise stated. 6MWD: 6-min walk distance; P̄_ra: mean right atrial pressure; PVRI: pulmonary vascular resistance index. ^#: body mass index ≥30 kg·m⁻². Reproduced from [15] with permission from the publisher.