Table 5– Baseline characteristics for group 3: pulmonary hypertension due to lung disease and/or hypoxia

	IPAH	COPD	ILD	Sleep disorders and alveolar hypoventilation
Subjects n	175	101	32	25
Age yrs	55±16^#,¶	69±10^§	68±11^§	61±10
Female	67^#,¶,+	37^§	22^§	44^§
WHO III/IV	67/20^¶	67/25⁺	53/44^+,§	67/8^#,¶
ISWD m	183±173^#,¶	102±105^§	97±97^§	145±99
P̄_ra mmHg	11±6	10±5	8±7	11±7
P̄_pa mmHg	53±13^#,¶,+	43±11^§	39±9^§	37±10^§
CI L·min⁻¹·m⁻²	2.3±0.8^#,+	2.8±0.9^§	2.5±0.6⁺	3.2±0.7^¶,§
P_pcw mmHg	10±3^#,+	13±5^+,§	11±8⁺	16±10^#,¶,§
PVR dyn·s·cm⁻⁵	960±465^#,¶,+	568±382^§	560±321^§	375±284^§
S_v,O₂ %	61±9^#,+	64±8^§	63±10	69±8^§
FEV₁ % pred	86±15^#,¶,+	59±26^§	66±25^§	51±23^§
FVC % pred	97±18^#,¶,+	85±25^¶,+,§	66±25^#,§	56±23^#,§
T_L,CO % pred	52±21^#,¶	32±16^+,§	32±9^+,§	57±19^#,¶

Data are presented as mean±sd or %, unless otherwise stated. Idiopathic pulmonary arterial hypertension (IPAH) data are shown for comparison. COPD: chronic obstructive pulmonary disease; ILD: interstitial lung disease; WHO: World Health Organization functional class; ISWD: incremental shuttle walking distance; P̄_ra: mean right atrial pressure; P̄_pa: mean pulmonary artery pressure; CI: cardiac index; P_pcw: pulmonary capillary wedge pressure; PVR: pulmonary vascular resistance; S_v,O₂: mixed venous oxygen saturation; FEV₁: forced expiratory volume in 1 s; % pred: % predicted; FVC: forced vital capacity; T_L,CO: transfer factor of the lung for carbon monoxide. ^#: p<0.05 in comparison to COPD; ^¶: p<0.05 in comparison to ILD; ⁺: p<0.05 in comparison to sleep/alveolar hypoventilation; ^§: p<0.05 in comparison to IPAH.