Table 2

Patients’ demographic and clinical characteristics at baseline in the validation cohort

CharacteristicsValidation cohort (n=117)Progressors (n=25)Non-progressors (n=92)P values
Demographic
  Age (year)53.7±14.655.4±13.653.3±14.90.569
  Male sex19 (16.2)7 (28.0)12 (13.0)0.121
  Disease duration (year)*7.6±6.6 (n=107)7.2±6.9 (n=23)7.7±6.5 (n=84)0.609
Extrapulmonary
  Anti-Scl-70 positive43/115 (37.4)9 (36.0)34/90 (37.8)0.871
  ACA positive22/115 (19.1)4 (16.0)18/90 (20.0)0.779
  Anti-CCP positive6/92 (6.5)2/19 (10.5)4/73 (5.5)0.600
  Diffuse cutaneous subset57 (48.7)12 (48.0)45 (48.9)0.935
  mRSS (unit)9.1±9.4 (n=116)9.6±9.9 (n=24)9.0±9.40.761
  Arthritis ever†35 (29.9)14 (56.0)21 (22.8)0.001
  ESR>20 mm/1 hour32/114 (28.1)6 (24.0)26/89 (29.2)0.608
  CRP elevation32/116 (27.6)7 (28.0)25/91 (27.5)0.958
Lung-associated
  FVC (% predicted)97.6±16.5100.0±16.497.0±16.50.287
  DLCO (% predicted)66.7±15.160.5±13.268.4±15.30.020
  Ground glass opacification39/102 (38.2)5/22 (22.7)34/80 (42.5)0.091
  Honey combing13/98 (13.3)2/21 (9.5)11/77 (14.3)0.728
  Dyspnoea NYHA≥247 (40.2)11 (44.0)36 (39.1)0.660
  6 min walk distance (m)505.3±95.1 (n=93)472.9±106.3 (n=20)514.2±90.6 (n=73)0.164
  SpO2 before 6MWT (%)97.9±1.3 (n=88)97.2±1.5 (n=20)98.1±1.1 (n=68)0.009
  SpO2 after 6MWT (%)96.3±2.3 (n=80)94.3±2.4 (n=18)96.9±1.9 (n=62)<0.001
  Oxygen desaturation (%)1.5±1.7 (n=80)2.7±1.7 (n=18)1.1±1.6 (n=62)<0.001
 Immunosuppressive therapy‡45 (38.5)12 (48.0)33 (35.9)0.269
  • Data are presented as mean±SD for continuous variables and number (frequency) (%) for categorical variables.

  • *Disease duration was calculated as difference between the date of the baseline visit and the date of the first non-Raynaud’s symptom of the disease as reported by the patients.

  • †Arthritis ever was defined as one or more tender and swollen joints as judged by the treating physician ever existed currently or before the baseline visit.

  • ‡Immunosuppressive therapy was defined as treatment with prednisone in doses >10 mg/day or any immunosuppressant (cyclophosphamide, methotrexate, azathioprine, mycophenolate, rituximab and tocilizumab) at baseline.

  • 6MWT, 6 min walk test; anti-Scl-70, antitopoisomerase-I antibodies; ACA, anticentromere antibody; anti-CCP, anticyclic citrullinated peptide; CRP, C reactive protein; DLCO, diffusing capacity for carbon monoxide; ESR, erythrocyte sedimentation rate; FVC, forced vital capacity; NYHA, New York Heart Association; mRSS, modified Rodnan Skin Score; SpO2, peripheral capillary oxygen saturation.