Baseline characteristics of patients with anti-MDA5+DM with different HRCT patterns
| Parameters | NSIP (n=87, group 1) | OP (n=142, group 2) | NSIP+OP (n=61, group 3) | UIP (n=2, group 4) | DAD (n=5, group 5) | Unclassifiable (n=7, group 6) | Other types (n=4, group 7) | Adjusted p value (pairwise comparison of the groups) |
| General characteristics | ||||||||
| Age, median (IQR), years | 49.0 (41.0, 56.0) | 48.0 (40.0, 57.3) | 54.0 (49.5, 59.0) | 62.5 (57.0, *) | 56.0 (45.0, 63.5) | 54.0 (39.0, 67.0) | 45.0 (35.3, 55.5) | NS |
| Female, n (%) | 54 (62.1) | 107 (75.4) | 38 (62.3) | 0 (0.0) | 4 (80.0) | 7 (100.0) | 3 (75.0) | NS |
| Smoking history, n (%) | 17 (19.5) | 15 (10.6) | 12 (19.7) | 1 (50.0) | 1 (20.0) | 0 (0.0) | 0 (0.0) | NS |
| Malignancy, n (%) | 2 (2.3) | 3 (2.1) | 5 (8.2) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | NS |
| Disease duration, median (IQR), months | 4.0 (2.0, 8.0) | 4.0 (2.0, 7.0) | 2.0 (1.0, 4.5) | 5.5 (2.0, *) | 4.0 (2.0, 6.5) | 4.0 (3.0, 6.0) | 1.8 (0.9, 2.0) | NS |
| Disease onset to ILD diagnosis, median (IQR), months | 2.0 (1.0, 4.0) | 2.0 (1.0, 4.0) | 1.0 (1.0, 1.8) | 5.0 (2.0, *) | 2.0 (1.0, 3.5) | 4.0 (1.0, 6.0) | 0.9 (0.6, 1.8) | <0.05 (groups 1–3) <0.05 (groups 2–3) |
| Disease onset to initial treatment, median (IQR), months | 2.0 (1.0, 3.0) | 2 (1.0, 3.0) | 1.0 (1.0, 2.0) | 5.0 (2.0, *) | 1.0 (1.0, 3.0) | 4.0 (1.0, 6.0) | 0.9 (0.6, 1.8) | 0.006 (groups 1–3) 0.011 (groups 2–3) |
| RPILD, n (%) | 38 (43.7) | 79 (55.6) | 47 (77.0) | 2 (100.0) | 5 (100.0) | 4 (57.1) | 2 (50.0) | <0.05 (groups 1–3) |
| Pulmonary infection, n (%) | 51 (58.6) | 98 (69.0) | 47 (77.0) | 2 (100.0) | 4 (80.0) | 6 (85.7) | 3 (75.0) | NS |
| Clinical features at initial visit | ||||||||
| Heliotrope rash, n (%) | 67 (77.0) | 116 (81.7) | 35 (57.4) | 2 (100.0) | 2 (40.0) | 4 (57.1) | 3 (75.0) | <0.05 (groups 2–3) |
| Gottron’s sign, n (%) | 74 (85.1) | 118 (83.1) | 51 (83.6) | 2 (100.0) | 2 (40.0) | 6 (85.7) | 2 (50.0) | NS |
| Mechanic’s hand, n (%) | 48 (55.2) | 78 (54.9) | 38 (62.3) | 1 (50.0) | 0 (0.0) | 4 (57.1) | 2 (50.0) | NS |
| Distal digital tip ulceration, n (%) | 20 (23.0) | 49 (34.5) | 15 (24.6) | 0 (0.0) | 1 (20.0) | 1 (14.3) | 2 (50.0) | NS |
| V sign, n (%) | 43 (49.4) | 79 (55.6) | 27 (44.3) | 1 (50.0) | 1 (20.0) | 2 (28.6) | 2 (50.0) | NS |
| Shawl sign, n (%) | 32 (36.8) | 61 (43.0) | 19 (31.1) | 1 (50.0) | 1 (20.0) | 2 (28.6) | 1 (25.0) | NS |
| Myalgia, n (%) | 36 (41.4) | 67 (47.2) | 17 (27.9) | 2 (100.0) | 2 (40.0) | 6 (85.7) | 2 (50.0) | <0.05 (groups 3–6) |
| Muscle weakness, n (%) | 55 (63.2) | 85 (59.9) | 31 (50.8) | 2 (100.0) | 1 (20.0) | 7 (100.0) | 4 (100.0) | NS |
| Fever, n (%) | 47 (54.0) | 63 (44.4) | 40 (65.6) | 2 (100.0) | 5 (100.0) | 4 (57.1) | 1 (25.0) | NS |
| Laboratory findings | ||||||||
| Creatine kinase, median (IQR), IU/L | 35.5 (23.0, 126.3) | 52.5 (28.0, 109.3) | 48.0 (24.0, 107.8) | 92.5 (58.0, *) | 111.0 (44.0, 181.0) | 68.0 (21.0, 115.0) | 150.5 (47.8, 423.5) | NS |
| Lymphocyte count, median (IQR), ×109/L | 0.79 (0.53, 1.06) | 0.74 (0.48, 0.93) | 0.66 (0.51, 0.94) | 0.56 (0.54, *) | 0.45 (0.15, 0.72) | 0.60 (0.30, 0.70) | 0.73 (0.47, 1.46) | NS |
| Lactate dehydrogenase, median (IQR), IU/L | 290.0 (235.0, 378.0) | 301.5 (254.0, 357.5) | 359.5 (284.5, 492.0) | 273.0 (267.0, *) | 667.0 (514.5, 840.5) | 483.0 (316.0, 654.0) | 374.0 (282.5, 502.3) | 0.014 (groups 1–3) 0.009 (groups 2–3) 0.008 (groups 1–5) 0.009 (groups 2–5) |
| Ferritin, median (IQR), ng/mL | 456.8 (208.8, 1078.4) | 553.5 (173.4, 1151.9) | 993.3 (658.1, 1923.0) | 1007.7 (886.8, *) | 978.6 (365.7, 3349.3) | 551.6 (158.7, 1005.0) | 569.8 (292.6, 2181.5) | 0.001 (groups 1–3) 0.002 (groups 2–3) |
| Anti-Ro-52 antibody-positive, n (%) | 55 (63.2) | 89 (62.7) | 46 (75.4) | 2 (100.0) | 3 (60.0) | 3 (42.9) | 3 (75.0) | NS |
| Treatment after admission | ||||||||
| Steroid used, n (%) | 86 (98.9) | 140 (98.6) | 60 (98.4) | 2 (100.0) | 4 (80.0) | 7 (100.0) | 4 (100.0) | NS |
| PMT, n (%) | 5 (5.7) | 8 (5.6) | 7 (11.5) | 0 (0.0) | 2 (40.0) | 0 (0.0) | 0 (0.0) | NS |
| Immunosuppressant used, n (%) | 79 (90.8) | 123 (86.6) | 45 (73.8) | 2 (100.0) | 3 (60.0) | 6 (85.7) | 2 (50.0) | NS |
| CYC | 14 (16.1) | 11 (7.7) | 3 (4.9) | 1 (50.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | NS |
| CNI | 54 (62.1) | 102 (71.8) | 40 (65.6) | 1 (50.0) | 2 (40.0) | 3 (42.9) | 2 (50.0) | NS |
| MMF | 7 (8.0) | 7 (4.9) | 2 (3.3) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | NS |
| JAKi | 10 (11.5) | 12 (8.5) | 5 (8.2) | 0 (0.0) | 1 (20.0) | 2 (28.6) | 0 (0.0) | NS |
| Biological agents | 3 (3.4) | 7 (4.9) | 6 (9.8) | 0 (0.0) | 0 (0.0) | 1 (14.3) | 0 (0.0) | NS |
| Total number of immunosuppressant ≥2, n (%) | 33 (37.9) | 38 (26.8) | 16 (26.2) | 0 (0.0) | 1 (20.0) | 3 (42.9) | 0 (0.0) | NS |
| IVIG, n (%) | 24 (27.6) | 51 (35.9) | 26 (42.6) | 0 (0.0) | 3 (60.0) | 1 (14.3) | 1 (25.0) | NS |
| ICU admission, n (%) | 7 (8.0) | 10 (7.0) | 15 (24.6) | 0 (0.0) | 5 (100.0) | 2 (28.6) | 1 (25.0) | <0.05 (groups 2–3) <0.05 (groups 1–5) <0.05 (groups 2–5) <0.05 (groups 3–5) |
| Mechanical ventilation, n (%) | 6 (6.9) | 12 (8.5) | 17 (27.9) | 0 (0.0) | 5 (100.0) | 2 (28.6) | 1 (25.0) | <0.05 (groups 1–3) <0.05 (groups 1–5) <0.05 (groups 2–3) <0.05 (groups 2–5) <0.05 (groups 3–5) |
| VV-ECMO, n (%) | 0 (0.0) | 2 (1.4) | 1 (1.6) | 0 (0.0) | 3 (60.0) | 0 (0.0) | 0 (0.0) | <0.05 (groups 1–5) <0.05 (groups 2–5) <0.05 (groups 3–5) |
| Lung transplantation, n (%) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | NS |
| 12-month mortality | 12 (13.8) | 27 (19) | 28 (45.9) | 0 (0.0) | 5 (100.0) | 2 (28.6) | 1 (25.0) | <0.05 (groups 1–3) <0.05 (groups 2–3) <0.05 (groups 1–5) <0.05 (groups 2–5) |
*Incomplete data due to small number of cases in the UIP group.
Anti-MDA5+DM, anti-melanoma differentiation-associated gene 5 antibody-positive dermatomyositis; CNI, calcineurin inhibitors; CYC, cyclophosphamide; DAD, diffuse alveolar damage; HRCT, high-resolution CT; ICU, intensive care unit; ILD, interstitial lung disease; IVIG, intravenous immunoglobulin; JAKi, Janus kinase inhibitors; MMF, mycophenolate mofetil; NS, no significance; NSIP, non-specific interstitial pneumonia; OP, organising pneumonia; PMT, pulse methylprednisolone therapy; RPILD, rapidly progressive interstitial lung disease; UIP, usual interstitial pneumonia; VV-ECMO, venovenous extracorporeal membrane oxygenation.