Table 1

Demographics and baseline characteristics of the study population

CharacteristicPlacebo (n=90)Bosentan (n=98)
Men/women, % of patients20/8022/78
Age in years, mean (SD)50.7 (12.0)48.4 (12.9)
Weight in kg, mean (SD)66.5 (15.8)64.7 (13.6)
Caucasian/black/other,* % of patients83/6/1187/7/6
Smoking status, % of patients
 Never/previous/current56/23/2264/23/13
SSc characteristics
 Limited/diffuse, % of patients58/4260/40
 Time from diagnosis of scleroderma to randomisation in years, mean (SD)8.7 (7.7)8.7 (8.4)
DU characteristics
 Number at baseline, mean (SD)3.6 (3.3)3.7 (4.4)
 Time from first occurrence of DUs to randomisation in years, mean (SD)6.4 (7.1)7.4 (8.7)
Selected concomitant medication at baseline, % of patients
 Calcium channel blockers5650
 Anti-inflammatory and antirheumatic products3740
 ACE inhibitors1416
 Peripheral vasodilators§1013
 Angiotensin II receptor blockers98
 Phosphodiesterase inhibitor (sildenafil)33
  • * Other races included Asian, Hispanic, Indian, Native American and mixed.

  • Smoking status was available for 88 and 94 patients in the placebo and bosentan groups, respectively, and the time from first occurrence of DUs to randomisation for 89 and 98 patients, respectively.

  • Limited=skin thickening only distal to the elbows and knees. Diffuse=skin thickening proximal to the elbows or knees or affecting the trunk.

  • § As defined by the WHO Drug Dictionary and included pentoxifylline, buflomedil, ginkgo tree leaves extract and ginkgo biloba.

  • ACE, angiotensin-converting enzyme; DU, digital ulcer; SSc, systemic sclerosis.