Table 1.
Characteristics of the EUSTAR patients analyzed and not analyzed and characteristics of the patients in the present study by cutaneous subseta
| EUSTAR population | Study population | |||||
|---|---|---|---|---|---|---|
| Patients analyzed (n = 6,927) | Patients not analyzed (n = 1,505) | P b | dcSSc | lcSSc | P b | |
| % of patients | – | – | – | 42 | 58 | – |
| Demographic characteristics | ||||||
| Sex, female | 86 (6,924) | 83 (1,505) | <0.001 | 80 | 91 | <0.001 |
| Ethnicity | <0.001 | <0.001 | ||||
| White | 95 (3,973) | 87 (1,176) | 92 | 97 | ||
| Asian | 3 (3,973) | 11 (1,176) | 5 | 2 | ||
| Black | 2 (3,973) | 2 (1,176) | 3 | 1 | ||
| Age, mean ± SD years (n) | 58.7 ± 13.2 (6,927) | 56.3 ± 13.9 (1,505) | <0.001 | 55.6 ± 13.0 | 60.9 ± 13.0 | <0.001 |
| Age at first non–Raynaud's phenomenon symptom, mean ± SD years (n) | 47.3 ± 13.3 (6,927) | 47.6 ± 14.1 (1,505) | 0.474 | 45.6 ± 13.2 | 48.5 ± 13.3 | <0.001 |
| Disease duration, mean ± SD years (n)c | 11.4 ± 8.1 (6,927) | 8.7 ± 8.1 (1,505) | <0.001 | 10.0 ± 7.4 | 12.4 ± 8.5 | <0.001 |
| Time from onset of Raynaud's phenomenon to first non–Raynaud's phenomenon symptom, mean ± SD years (n) | 3.9 ± 8.0 (5,868) | 3.4 ± 8.1 (1,351) | <0.001 | 2.0 ± 5.6 | 5.2 ± 9.2 | <0.001 |
| Time from first non–Raynaud's phenomenon symptom to EUSTAR enrollment, mean ± SD years (n) | 9.4 ± 7.8 (4,875) | 7.8 ± 7.8 (1,271) | <0.001 | 8.0 ± 7.3 | 10.3 ± 8.1 | <0.001 |
| Time from EUSTAR enrollment to last visit, mean ± SD years (n) | 2.6 ± 2.5 (4,875) | 0.8 ± 1.7 (1,271) | <0.001 | 2.7 ± 2.6 | 2.5 ± 2.5 | 0.031 |
| Body mass index, mean ± SD kg/m2 (n) | 23.6 ± 4.3 (2,483) | 24.4 ± 4.8 (889) | <0.001 | 22.9 ± 4.0 | 24.1 ± 4.4 | <0.001 |
| SSc characteristics | ||||||
| Autoantibody status | ||||||
| Antinuclear antibody positived | 96 (6,927) | 94 (1,412) | <0.001 | 97 | 96 | 0.400 |
| Anticentromere antibody positived | 37 (6,927) | 36 (1,264) | 0.751 | 14 | 54 | <0.001 |
| Anti–topoisomerase I antibody positived | 39 (6,927) | 36 (1,270) | 0.028 | 61 | 23 | <0.001 |
| Anti–U1 RNP antibody positive | 5 (4,054) | 7 (807) | 0.006 | 5 | 5 | 0.770 |
| Anti‐PM/Scl antibody positive | 3 (3,335) | 4 (648) | 0.278 | 5 | 2 | <0.001 |
| Anti–RNA polymerase III antibody positive | 4 (3,163) | 6 (563) | 0.025 | 6 | 3 | <0.001 |
| Cutaneous involvement | ||||||
| dcSSc | 42 (6,913) | 38 (1,437) | 0.011 | – | – | – |
| Peak MRSS value, mean ± SD (n)d | 12.0 ± 9.2 (6,927) | 10.9 ± 9.7 (1,170) | <0.001 | 18.3 ± 9.8 | 7.5 ± 5.2 | <0.001 |
| Gastrointestinal involvemente | ||||||
| Esophageal symptomsd | 81 (6,927) | 69 (1,498) | <0.001 | 84 | 79 | <0.001 |
| Stomach symptomsd | 42 (6,927) | 27 (1,491) | <0.001 | 47 | 38 | <0.001 |
| Intestinal symptomsd | 43 (6,927) | 33 (1,497) | <0.001 | 44 | 42 | 0.027 |
| Joint involvement | ||||||
| Joint contracturesd | 48 (6,927) | 35 (1,492) | <0.001 | 64 | 36 | <0.001 |
| Joint synovitisd | 26 (6,927) | 18 (1,496) | <0.001 | 32 | 22 | <0.001 |
| Tendon friction rubsd | 17 (6,927) | 8 (1,477) | <0.001 | 28 | 9 | <0.001 |
| Vascular involvement | ||||||
| Raynaud's phenomenond | 98 (6,927) | 97 (1,500) | <0.001 | 98 | 98 | 0.340 |
| History of or current digital ulcersd | 49 (6,927) | 35 (1,491) | <0.001 | 58 | 42 | <0.001 |
| Muscular involvement | ||||||
| Muscle weaknessd | 39 (6,927) | 24 (1,488) | <0.001 | 47 | 33 | <0.001 |
| Muscle atrophyd | 22 (6,927) | 12 (1,484) | <0.001 | 30 | 16 | <0.001 |
| CK elevationd | 13 (6,927) | 13 (1,231) | 0.711 | 18 | 9 | <0.001 |
| Cardiac involvement | ||||||
| Systemic arterial hypertensiond | 34 (6,927) | 27 (1,492) | <0.001 | 33 | 35 | 0.150 |
| Palpitationsd | 39 (6,927) | 26 (1,483) | <0.001 | 41 | 38 | 0.014 |
| Conduction blocksd | 22 (6,927) | 14 (1,152) | <0.001 | 24 | 20 | <0.001 |
| LVEF <50% | 5 (4,239) | 5 (879) | 0.799 | 6 | 4 | <0.001 |
| Abnormal diastolic functiond | 33 (6,927) | 22 (1,116) | <0.001 | 34 | 33 | 0.588 |
| Pericardial effusion | 11 (4,442) | 8 (920) | 0.042 | 13 | 9 | <0.001 |
| Pulmonary hypertension | ||||||
| Pulmonary hypertension on echocardiographyd | 31 (6,927) | 22 (1,173) | <0.001 | 33 | 29 | <0.001 |
| Systolic PAP measured by echocardiography, mean ± SD mm Hg (n) | 34.5 ± 15.3 (3,983) | 34.2 ± 15.1 (727) | 0.041 | 34.8 ± 16.4 | 34.2 ± 14.5 | 0.013 |
| Interstitial lung disease | ||||||
| Lung fibrosis on plain radiographyd | 49 (6,927) | 39 (1,033) | <0.001 | 63 | 39 | <0.001 |
| Lung fibrosis on HRCT | 57 (3,424) | 53 (816) | 0.023 | 68 | 48 | <0.001 |
| Restrictive defect on PFTsd | 43 (6,927) | 33 (1,083) | <0.001 | 57 | 32 | <0.001 |
| FVC, mean ± SD % predicted (n) | 89.3 ± 21.7 (4,349) | 90.0 ± 21.8 (903) | 0.437 | 81.4 ± 21.1 | 94.9 ± 20.3 | <0.001 |
| Dlco, mean ± SD % predicted (n) | 61.8 ± 20.1 (6,196) | 66.1 ± 21.1 (1,026) | <0.001 | 57.4 ± 19.9 | 64.9 ± 19.7 | <0.001 |
| 6‐minute walking distance, mean ± SD meters (n) | 392 ± 134 (1,179) | 411 ± 145 (338) | 0.007 | 394 ± 137 | 391 ± 131 | 0.872 |
| Renal involvement | ||||||
| History of renal crisisd | 3 (6,927) | 3 (1,497) | 0.626 | 5 | 2 | <0.001 |
| Proteinuriad | 12 (6,927) | 10 (1,308) | 0.082 | 15 | 9 | <0.001 |
| Blood tests | ||||||
| CRP elevation | 36 (4,736) | 31 (1,100) | <0.001 | 44 | 30 | <0.001 |
| Hypocomplementemia | 11 (4,469) | 10 (860) | 0.409 | 12 | 11 | 0.504 |
| Treatment | ||||||
| Past or current steroids | 43 (4,647) | 38 (1,081) | 0.006 | 55 | 34 | <0.001 |
| Prednisone, mean ± SD mg/day (n) | 4.4 ± 7.5 (4,644) | 5.1 ± 9.7 (1,080) | 0.081 | 6.0 ± 8.7 | 3.3 ± 6.1 | <0.001 |
| Past or current immunosuppressive drugs | 42 (4,631) | 44 (1,085) | 0.162 | 60 | 28 | <0.001 |
a
Except where indicated otherwise, values are the percent (number with data available). EUSTAR = European Scleroderma Trials and Research; dcSSc = diffuse cutaneous systemic sclerosis; lcSSc = limited cutaneous systemic sclerosis; MRSS = modified Rodnan skin thickness score; CK = creatine kinase; LVEF = left ventricular ejection fraction; PAP = pulmonary artery pressure; HRCT = high‐resolution computed tomography; PFTs = pulmonary function tests; FVC = forced vital capacity; DLco = diffusing capacity for carbon monoxide; CRP = C‐reactive protein.
b
By Student's t‐test for continuous variables and Fisher's exact test for categorical variables.
c
Time between the first non–Raynaud's phenomenon symptom and the last visit.
d
Clustering variables.
e
Esophageal symptoms included dysphagia and/or reflux, stomach symptoms included early satiety and/or vomiting, and intestinal symptoms included diarrhea, bloating, and/or constipation.