Table 1– Patient characteristics
All patientsIron-sufficientIron-deficientp-value#
Subjects n704030
Clinical parameters
 Age yrs52.2±15.651.8±16.652.8±14.5ns
 Males/females n15/5511/294/26ns
 NYHA classification II/III/IV n34/29/722/16/212/13/5ns
 Body mass index kg·m−226.1±5.326.4±5.125.7±5.8ns
 Oral anticoagulant use VKA/PAI/unknown/none n58/3/8/132/2/6/026/1/2/1ns
 Single/combination treatment n25/4518/227/23ns
 Duration of treatment months155.8±129.8127.6±86.7192.5±164.9ns+
Haemodynamic parameters
 Mean pulmonary arterial pressure mmHg50.2±14.151.0±13.649.1±14.9ns
 Mean right atrial pressure mmHg6.9±5.66.6±6.57.3±4.2ns+
 Pulmonary vascular resistance dyn·s·cm−5786±500808±516751±484ns+
 Cardiac output L·min−15.3±1.75.2±1.45.6±2.1ns
 Cardiac index L·min−1·m−22.7±0.92.6±0.82.9±0.9ns
 Arterial saturation %93±493±393±5ns
 Mixed venous saturation %65±866±863±9ns
 6MWD m431±144460±143390±138<0.05
 NT-proBNP ng·L−11022±1592941±17171128±1435ns+
Haematological parameters
 Hb g·dL−113.9±1.914.9±1.412.6±1.6<0.05
 Ht0.42±0.050.45±0.040.39±0.05<0.05
 MCV fL86±1291±580±16<0.05
 Serum iron μmol·L−112±616±57±3<0.05
 TIBC μmol·L−172±1368±977±16<0.05
 Transferrin saturation %17±923±710±5<0.05
 Ferritin μg·L−143±3866±3712±6<0.05
 Creatinine in males/females μmol·L−198±22/75±18103±24/79±2187±8/71±14ns
  • Data are presented as mean±sd, unless otherwise stated. NYHA: New York Heart Association; VKA: vitamin K antagonist; PAI: platelet aggregation inhibitor; 6MWD: 6-min walking distance; NT-proBNP: N-terminal pro-brain natriuretic peptide; Hb: haemoglobin; Ht: haematocrit; MCV: mean corpuscular volume; TIBC: total iron binding capacity; ns: nonsignificant. #: independent-sample t-testing to compare iron-sufficient with iron-deficient idiopathic pulmonary arterial hypertension patients and Fisher’s exact or Chi-squared testing for categorical data; : type of idipathic pulmonary arterial hypertension treatment (number of iron-sufficient/deficient patients) was endothelin receptor antagonists (24/19), phospodiesterase-5 inhibitor (20/26) and prostanoids (14/16); +: independent-sample t-testing after log transformation to obtain normal distribution.