TABLE 1

Baseline characteristics of the study population

CharacteristicsBBNo BBPartial BBp-value
Subjects n13337560
Age years59±1457±1655±160.22
BMI kg·m-229±828±826±60.12
Race0.84
 Caucasian97 (73)280 (75)40 (67)
 African-American27 (20)70 (18)12 (20)
 Hispanic4 (3)15 (4)7 (1)
 Asian5 (4)10 (3)3 (0.5)
Sex0.24
 Male46 (35)109 (29)23 (38)
 Female87 (65)265 (71)37 (62)
Smoking history0.27
 Never smoked74 (56)229 (61)37 (62)
 Ex-/current smoker59 (44)149 (39)23 (38)
Aetiology of PAH0.005
 Idiopathic47 (35)186 (50)27 (45)
 Connective tissue disease86 (65)189 (50)33 (55)
Co-existing cardiac illness
 Coronary artery disease13 (9)47 (12)7 (12)0.38
 Valvular heart disease13 (10)36 (10)9 (15)0.95
 Cardiac arrhythmias27 (20)80 (21)13 (22)0.79
 Dyslipidaemia54 (41)158 (42)20 (33)0.76
 Pericardial effusion21 (27)54 (21)10 (17)0.24
Comorbidities
 Diabetes mellitus27 (22)73 (20)14 (23)0.63
 Renal failure31 (23)88 (23)16 (26)0.64
 Hypertension27 (20)72 (19)13 (22)0.78
 Sleep apnoea12 (9)45 (12)7 (13)0.94
LVEF %56±756±858±80.56
Heart rate beats·min-171±1784±1574±190.01
Pro-BNP pg·mL−1780±218349±852511±403<0.016
Baseline NYHA functional class#0.52
 I2 (0.5)0
 II48 (38)125 (34)10 (19)
 III58 (46)180 (48)26 (43)
 IV20 (16)62 (17)16 (25)
Baseline 6MWD m286±111303±102221±590.15
Follow-up months median (range)81 (1.5–247)75 (1–388)31 (1.5–145)0.41
Transplant9 (7)25 (7)4 (7)0.97
Mortality69 (52)184 (49)32 (53)0.57
  • Data are presented as mean±sd or n (%), unless otherwise stated. BB: patients who had continued to use β-blockers until they reached the end-points of the study; no BB: patients who had never used β-blockers; partial BB: patients who were started on β-blocker therapy but discontinued after a period; BMI: body mass index; PAH: pulmonary arterial hypertension; LVEF: left ventricular ejection fraction; BNP: brain natriuretic peptide; NYHA: New York Heart Association; 6MWD: 6-min walking distance. #: n=126 (BB), n=369 (no BB) and n=52 (partial BB).