Table 1.
Demographic data of cohort 1 at the time of first available serum sample*
| IIM/ASSD (n=44) | Anti-Jo1+ (n=19) | Anti-Jo1− (n=25) | |
|---|---|---|---|
| Age, mean years (SD) | 57 (13) | 52 (14) | 61 (12)a |
| Women, n (%) | 24 (55) | 9 (47) | 15 (60) |
| Disease duration in months, median (25–75th percentiles)** | 0 (0–1) | 1 (0–10) | 0 (0–1) |
| Anti-synthetase syndrome (ASSD), n (%) | 28 (64) | 19 (100) | 9 (36)b |
| Muscular manifestations, n ever (%) | |||
| Muscle weakness (pathological MMT8 and/or FI-2) | 35 (83) | 15 (79) | 20 (87) |
| Muscle enzymes elevation (CK, LD, ASAT, ALAT) | 35 (83) | 15 (79) | 20 (87) |
| Muscle inflammatory infiltrates | 26 (62) | 11 (58) | 15 (65) |
| Extra-muscular manifestations, n ever (%) | |||
| Interstitial lung disease (ILD) | 25 (57) | 16 (84) | 9 (36)c |
| Skin rash*** | 14 (32) | 5 (26) | 9 (36) |
| Arthritis | 18 (41) | 11 (58) | 7 (28) |
| Dysphagia | 9 (21) | 3 (16) | 6 (24) |
| Raynaud’s phenomenon | 2 (5) | 2 (11) | 0 (0) |
| Smoking status, n ever (%) | 24 (55) | 10 (53) | 14 (56) |
| Laboratory tests | |||
| CK, median μcat/L (25–75th percentiles) | 4.3 (1.4–14.2) | 3.8 (1.1–9.0) | 4.4 (1.6–16.2) |
| CRP, median mg/L (25–75th percentiles) | 4.0 (0.9–8.3) | 7.0 (2.0–9.0) | 2.0 (0.5–8.0) |
| Autoantibodies | |||
| Positive anti-PL7, n (%) | 2 (5.1) | 0 | 2 (8.3) |
| Positive anti-PL12, n (%) | 2 (5.1) | 0 | 2 (8.3) |
| Positive anti-EJ, n (%) | 1 (2.6) | 0 | 1 (4.2) |
| Positive anti-OJ, n (%) | 3 (7.7) | 0 | 3 (12.5) |
| Positive anti-Mi-2, n (%) | 3 (7.9) | 1 (7.1) | 2 (8.3) |
| Positive anti-SRP, n (%) | 2 (5.1) | 0 | 2 (8.3) |
| Positive anti-MDA5, n (%) | 3 (7.9) | 0 | 3 (12.5) |
| Positive anti-TIF1g, n (%) | 3 (7.9) | 0 | 3 (12.5) |
| Positive anti-SSA, n (%) | 16 (36.4) | 10 (52.6) | 6 (24.0) |
| Positive anti-Ro52, n (%) | 12 (38.7) | 8 (47.1) | 4 (28.6) |
| Positive anti-SSB, n (%) | 0 | 0 | 0 |
| Positive anti-U1 RNP, n (%) | 5 (11.4) | 2 (10.5) | 3 (12.0) |
| Positive anti-Ku, n (%) | 1 (2.5) | 0 | 1 (4.0) |
| Positive anti-PmScl, n (%) | 2 (4.9) | 1 (6.3) | 1 (4.0) |
| Physician VAS, median (25–75th percentiles) | 40 (25– 60) | 45 (32–60) | 40 (17–50) |
| Patient VAS, median (25–75th percentiles) | 40 (16–69) | 44 (19–70) | 32 (11–68) |
| HAQ (1–3), median (25–75th percentiles) | 0.88 (0.00–1.50) | 0.75 (0.19–1.25) | 1.00 (0.00–1.63) |
| MMT-8 (0–80), median (25–75th percentiles) | 78 (67–80) | 79 (77–80) | 75 (64–80) |
| Muscle activity score VAS, median (25–75th percentiles) | 15 (0 37.5) | 4.5 (0–35.5) | 15 (0–37.5) |
| MDAAT, median (25–75th percentiles) | 0.07 (0.05–0.16) | 0.12 (0.05–0.17) | 0.06 (0.03–0.16) |
| Extra-muscular activity, median (25–75th percentiles) | 32 (15–40) | 40 (11–43) | 24 (16–34) |
| Immunosuppressive (IS) treatment, n (%) | |||
| No treatment | 10 (26) | 4 (25) | 6 (26) |
| 1 treatment | 10 (26) | 2 (13) | 8 (35) |
| 2 or 3 concomitant treatments | 19 (49) | 10 (63) | 9 (39) |
| Healthy controls (n=24) | |||
| Age, mean years (SD) | 59.3 (13.0) | ||
| Women, n (%) | 12 of 24 (50) | ||
*First available serum samples collected: (i) at diagnosis (0 months), sera were available from 6 anti-Jo1+ and 14 anti-Jo1− patients; (ii) before diagnosis, sera were available from 3 anti-Jo1+ and 4 anti-Jo1− patients (median months [25–75th percentile], −1 [−3 to −1] and −10[−19.5 to −4.25], respectively); (iii) after diagnosis, sera were available from 10 anti-Jo1+ and 7 anti-Jo1− patients (9 [1–99] and 1 [1–4], respectively).
IIM idiopathic inflammatory myopathies; ASSD anti-synthetase syndrome; CK creatinine kinase (reference values: 0.6–3.5 μkat/L); CRP C-reactive protein (0–3 mg/L); VAS visual analogue scale; MDDAT Myositis Disease Activity Assessment Tool; HAQ Health Assessment Questionnaire; MMT-8 Manual Muscle Testing
1 treatment designates one of the following: methotrexate (Mtx), glucocorticoids (GC), intravenous immunoglobulin, or abatacept; 2 or 3 concomitant treatments designate all the possible following combinations: GC + azathioprine (Aza), GC + cyclophosphamide, GC + Mtx, GC + mycophenolate mofetil (MMF), GC + rituximab, GC + cyclophosphamide + rituximab, GC + Mtx + rituximab, or GC + MMF + rituximab
**Disease duration was calculated based on month and year of clinical diagnosis; ***Skin rash features: Periungual erythema, mechanic’s hand, Gottron’s sign, Gottron’s papules, V-sign, shawl sign, alopecia, erythroderma, periorbital edema, heliotrope rash
ap = 0.0236; bp < 0.0001; cp = 0.0020 vs anti-Jo1+ (Mann-Whitney’s test for quantitative variables and Fisher’s exact test for analysis of categorical variables were employed)