Table 3.
Baseline characteristics of SSc patients positive for anti–topo I IgG, stratified according to presence or absence of disease progression over 1 year of follow‐up*
|
Disease progressors (n = 23) |
Disease nonprogressors (n = 58) |
P | |
|---|---|---|---|
| Demographic characteristics | |||
| Female sex | 14 (61) | 39 (67) | 0.59 |
| Age, mean ± SD years | 55.3 ± 16.3 | 51.9 ± 13.9 | 0.21 |
| Smoking (ever) | 12 (52) | 30 (52) | 0.95 |
| Disease duration | |||
| Since onset of first Raynaud’s symptom, median (IQR) years | 3.8 (1.3–8.4) | 5.6 (2.1–12.9) | 0.21 |
| Since onset of first non‐Raynaud’s symptom, median (IQR) years | 1.9 (0.6–4.5) | 3.5 (0.7–11.4) | 0.07 |
| Organ involvement | |||
| Diffuse cutaneous SSc | 12 (52) | 28 (48) | 1.00 |
| Modified Rodnan skin thickness score, median (IQR) | 6 (2–19) | 6 (3–13) | 0.86 |
| FVC%, mean ± SD | 89 ± 26 | 89 ± 28 | 0.92 |
| DLco%, mean ± SD | 62 ± 18 | 64 ± 16 | 0.83 |
| History of renal crisis | 0 (0) | 2 (4) | 1.00 |
| Digital ulcers | 0 (0) | 5 (9) | 0.31 |
| Pulmonary hypertension | 2 (9) | 2 (4) | 0.59 |
| History of immunosuppressive treatment† | |||
| HSCT | 0 (0) | 7 (12) | 0.18 |
| CYC (ever) | 4 (17) | 16 (28) | 0.34 |
| MMF (ever) | 1 (4) | 0 (0) | 0.28 |
| Use of immunosuppressive treatment during 1‐year follow‐up† | |||
| HSCT | 0 (0) | 0 (0) | – |
| CYC | 11 (19) | 5 (26) | 0.52 |
| MMF | 1 (5) | 6 (10) | 0.67 |
| Anti–topo I antibody characteristics | |||
| IgG level, median (IQR) AU/ml | 813 (542–1,263) | 396 (115–832) | <0.01 |
| IgA positivity | 23 (100) | 57 (98) | 1.00 |
| IgA level, median (IQR) AU/ml | 9,898 (2,743–16,656) | 2,045 (462–5,314) | <0.01 |
| IgM positivity | 21 (91) | 33 (57) | 0.04 |
| IgM level, median (IQR) AU/ml | 1065 (869–3,853) | 588 (223–1,610) | 0.01 |
In 22 individuals, clinical follow‐up data were not available and they could not be classified as either disease progressors or disease nonprogressors. Except where indicated otherwise, values are the number (%) of patients. SSc = systemic sclerosis; anti–topo I = anti–topoisomerase I; IQR = interquartile range; FVC% = forced vital capacity % predicted; DLco% = diffusing capacity for carbon monoxide % predicted.
Immunosuppressive treatment includes the use of hematopoietic stem cell transplantation (HSCT), cyclophosphamide (CYC), or mycophenolate mofetil (MMF).