Table 2.

Etiology of Disease: Risk Factors Reported

	PH Overall (n = 750)		Comparator Overall (n = 347)
Group 1 Risk Factors	Primary G1 (n = 353)	G1 Risk Factors (n = 83)	Primary G1 Comparator (n = 58)	G1 Risk Factors (n = 72)
Idiopathic PAH	158	19	0	2
Connective tissue disease	93	54	41	31
Systemic sclerosis	42	23	21	16
Mixed connective tissue disease	16	7	5	3
Rheumatoid arthritis	7	10	9	9
Systemic lupus erythematosus	16	12	5	7
Other connective tissue disease (Sjögren’s, antisynthetase syndrome, undifferentiated)	15	5	8	8
Congenital heart disease	36	2	6	9
Shunt repaired	15	1	3	6
Familial PAH	27	3	1	0
HHT	4	2	0	0
HIV	10	4	0	2
Drug- and toxin-induced PAH	16	1	1	1
Portal hypertension	18	2	0	1
Mild PH (mPAP 21-<25 mm Hg)	0	0	10	27
ePAH (exercise mPAP ≤30 mm Hg, flow <10 L/min, and mPAP-Q slope >3) (mm Hg·min/L)	0	0	9	9
Connective tissue disease with mild (mPAP 21-<25 mm Hg) or no PH	0	0	43	27
Othera	10	0	0	0
Group 2 Risk Factors	Primary G2 (n = 136)	G2 Risk Factors (n = 105)	Primary G2 Comparator (n = 140)	G2 Risk Factors (n = 46)
Heart failure with preserved ejection fraction	100	83	76	28
Heart failure with reduced ejection fraction	26	13	19	2
Valvular heart disease	35	13	28	5
Stenotic	19	4	13	2
Regurgitant	29	12	19	3
Cardiomyopathy	14	2	28	2
Hypertrophic	7	1	6	0
Restrictive	6	0	2	0
Mild PVD risk associated with left heart disease (left heart disease with mPAP <25 mm Hg)	0	0	56	14
Moderate PVD risk associated with left heart disease	0	0	77	15
Isolated postcapillary pulmonary hypertension mPAP ≥25 mm Hg, PVR <3, DPG <7 (mm Hg)	0	0	56	8
Provocable mPCW >18 with V waves <5 mm Hg after challenge, significant change from resting hemodynamics	0	0	23	9
Provocable mPCW >15 with V waves >5 mm Hg after challenge, significant change from resting hemodynamics	0	0	45	6
Othera	3	2	3	0
Group 3 Risk Factors	Primary G3 (n = 172)	3 Risk Factors (n = 218)	Primary G3 Comparator (n = 119)	G3 Risk Factors (n = 116)
Obstructive sleep apnea/obesity hypoventilation	58	127	43	82
COPD	66	56	35	16
Mild to no PVD risk (mPAP <21 mm Hg) and COPD	0	0	7	3
Moderate PVD risk (mPAP 21-<25 mm Hg) and COPD	0	0	12	2
Idiopathic pulmonary fibrosis	15	7	13	1
Other ILD (including CPFE, other ILD, SSc-ILD, hypersensitivity pneumonitis)	75	49	35	14
Mild to no PVD risk (mPAP <21 mm Hg) and other ILD, including CPFE and SSc-ILD	0	0	12	3
Moderate PVD risk (mPAP 21-<25 mm Hg) and other ILD, including CPFE and SSc-ILD	0	0	6	5
Nonparenchymal restrictive lung disease/thoracic cage abnormality	8	9	8	7
Cystic fibrosis	3	0	3	0
Othera	2	2	1	3
Group 4 Risk Factors	Primary G4 (n = 57)	G4 Risk Factors (n = 14)	Primary G4 Comparator (n = 23)	G4 Risk Factors (n = 10)
Chronic thromboembolic pulmonary hypertension	57	14	0	0
Pulmonary thromboendarterectomy	18	0	5	3
Balloon pulmonary angioplasty	4	0	0	1
Chronic PE with mild to no PVD (mPAP <25 mm Hg)	0	0	21	6
Othera	0	0	2	1
Group 5 Risk Factors	Primary G5 (n = 32)	G5 Risk Factors (n = 9)	Primary G5 Comparator (n = 7)	G5 Risk Factors (n = 14)
Sarcoidosis	19	3	3	8
Myeloproliferative disease	3	3	1	5
Hemoglobinopathy	8	2	2	2
Sickle cell	7	1	2	2
Thalassemia	1	2	0	0
Othera	2	0	1	0

Values are n within group.

^aOther = schistosomiasis, pulmonary capillary hemangiomatosis, pulmonary veno-occlusive disease, or other conditions not otherwise listed.

CPFE = combined pulmonary fibrosis and emphysema; DPG = diastolic pressuregradient; G = group; ILD = interstitial lung disease; mPAP = mean pulmonary artery pressure; mPCW = mean pulmonary capillary wedge pressure; PAH = pulmonary arterial hypertension; PE = pulmonary embolism; PH = pulmonary hypertension; PVD = pulmonary vascular disease; PVR = pulmonary vascular resistance; SSc-ILD = scleroderma-associated interstitial lung disease.