Table 3– Clinical and haemodynamic data at the time of diagnosis in pulmonary arterial hypertension (PAH) subtypes and chronic thromboembolic pulmonary hypertension (CTEPH)

	PAH							CTEPH	ANOVA p-value
	IPAH	CTD	CHD	HIV	PoPH	TOS	PVOD	CTEPH	ANOVA p-value
Subjects n (%)	314 (30)	157 (15)	167 (16)	54 (5)	61 (6)	33 (3.2)	15 (1.5)	162 (16)
Age yrs	46±18	54±15 *	36±17*	39±5*	52±10*	39±13*	51±15	61±15*	<0.001
Males %	27	10*	27	42*	49	31	22	40*	<0.001
6MWD m	382±117	309±115*	365±101	416±126	396±109	372±139	314±127	317±112*	<0.001
WHO FC %
I–II	29	21	38	40	53	13	22	23	<0.001
III	59	64	54	40	46	72	44	68
IV	11	15	8	19	2	16	33	9
Haemodynamics
Mean P_pa mmHg	55±15	47±13*	68±19*	52±11	49±13*	67±17*	55±11	47±13*	<0.001
P_ra mmHg	8±5	9±6*	9±6	8±6	8±5	8±5	9±4	8±5	0.577
Cardiac index L·min⁻¹·m⁻²	2.4±0.7	2.6±0.9	3.0±0.9*	2.4±0.6	3.2±0.9*	2.2±0.5	2.2±0.5	2.3±0.5	<0.001
PVR Wood units	12±6	11±6*	13±7	12±6	7±3*	17±8*	13±6	10±5*	<0.001
S_v,O₂ %	62±9	59±11	66±10*	60±10	69±7*	59±8	57±17	61±10	<0.001

Data are presented as mean±sd, unless otherwise stated. IPAH: idiopathic PAH; CTD: connective tissue disease; CHD: congenital heart disease; PoPH: portopulmonary hypertension; TOS: toxic oil syndrome; PVOD: veno-occlusive disease; 6MWD: 6-min walk distance; WHO: World Health Organization; FC: functional class; P_pa: pulmonary artery pressure; P_ra: right atrial pressure; PVR: pulmonary vascular resistance; S_v,O₂: mixed-venous oxygen saturation. *: p<0.05 compared with IPAH.