Table 2.
Spearman’s rank correlations between selected myositis disease measures and interferon-regulated gene (IRG) scores
| 28 gene IRG score | Other IRG scores in JDM | ||||
|---|---|---|---|---|---|
| Assessment (n = 57) (range or upper limit of normal (ULN)) | JDM overall median, IQR | JDM overall (n = 57) | Anti-TIF1 Ab (n = 20)* | Bilgic et al. score‡ [6] | Greenberg et al. score§ [7] |
| 28 IRG score (n = 57) | 40.0 [1.8–236.0] | 40.0 [1.8–236.0] | 41.7 [−4.4–174.2] | 0.96** | 0.99** |
| Physician global activity (0–10 VAS, n = 56) | 2.2 [1.5–3.7] | 0.39|| | 0.31 | 0.42|| | 0.39|| |
| Total MMT (0–260, n = 36) | 242 [228–252] | − 0.36§ | − 0.13 | − 0.38§ | − 0.33 |
| CMAS (0–52, n = 38) | 43 [37–48] | − 0.26 | − 0.22 | − 0.21 | − 0.18 |
| CHAQ/HAQ (0–3.0, n = 42) | 0.75 [0.25–1.375] | 0.28 | 0.23 | 0.24 | 0.30 |
| MDAAT (0–10 VAS, n = 39) | |||||
| Muscle | 2.0 [1.0–2.9] | 0.31 | 0.29 | 0.40§ | 0.30 |
| Constitutional | 1.3 [0.3–3.3] | 0.09 | 0.21 | 0.09 | 0.11 |
| Cutaneous | 2.4 [1.1–3.8] | 0.29 | 0.62§ | 0.33§ | 0.30 |
| Pulmonary | 0.6 [0.0–1.4] | 0.23 | 0.44 | 0.29 | 0.21 |
| Skeletal (joint) | 0.9 [0.0–2.1] | 0.35§ | − 0.12 | 0.42|| | 0.36§ |
| Extra-muscular activity | 1.9 [1.2–3.2] | 0.47|| | 0.76|| | 0.53¶ | 0.48|| |
| (0–10 VAS, n = 40) | |||||
| Disease Activity Score (0–20, n = 39) | 11 [9–13] | 0.33§ | 0.58§ | 0.35§ | 0.33§ |
| DAS skin (0–9, n = 40) | 6 [5–7] | 0.16 | 0.73|| | 0.18 | 0.19 |
| DAS muscle (0–11, n = 39) | 5 [3.75–7] | 0.25 | 0.24 | 0.26 | 0.23 |
| Muscle enzymes (U/L) | |||||
| CK (ULN 252 U/L, n = 56) | 90 [52–170] | −0.09 | − 0.18 | − 0.11 | − 0.07 |
| Aldolase (ULN 7 U/L, n = 54) | 7.5 [5.8–10.1] | 0.24 | 0.18 | 0.25 | 0.24 |
| AST (ULN 34 U/L, n = 56) | 24 [18–33] | 0.42|| | 0.24 | 0.38|| | 0.43¶ |
| LDH (ULN 226 U/L, n = 56) | 186 [161–214] | 0.41|| | 0.27 | 0.39|| | 0.39|| |
| Physician global damage (0–10, n = 46) | 1.0 [0.4–2.0] | −0.05 | 0.04 | −0.09 | − 0.05 |
| MDI total damage (0–110, n = 34) | 4.0 [1.8–8.0] | 0.16 | 0.37 | 0.15 | 0.17 |
Abbreviations: IQR interquartile range, JDM juvenile dermatomyositis, anti-TIF1 subgroup of JDM positive for anti-TIF1 autoantibodies, Ab autoantibody, VAS visual analog scale, MMT manual muscle testing, CMAS Childhood Myositis Assessment Scale, CHAQ: Childhood Health Assessment Questionnaire, HAQ Health Assessment Questionnaire, MDAAT Myositis Disease Activity Assessment Tool, DAS Disease Activity Score, CK creatine kinase, AST aspartate aminotransferase, LDH lactate dehydrogenase, PGD Physician global damage, MDI Myositis Damage Index
§p ≤ 0.05, ||p ≤ 0.01, ¶p ≤ 0.001, **p ≤ 0.0001
*Proportionate numbers had assessments as JDM overall
†Bilgic et al. score: IFIT1, IRF7, and ISG15 as in [6]
‡Greenberg et al. score: EPSTI1, HERC5, IFI27, IFI44, IFI44L, IFI6, IFIT1, IFIT3, ISG15, MX1, OAS1, OAS3, and RSAD2 as in [7]