Table 3.
Clinical Characteristics, Treatment and Outcomes between IPAF subgroups and an IIM-ILD cohort
| Variable | IPAF without MSA/MAA (n=169) | IPAF-MSA (n=35) | p vs IPAF w/o MSA/MA A | IIM-ILD (n=70) | p vs IPAF - MSA |
|---|---|---|---|---|---|
| Age, mean (SD) | 63.3 (11.2) | 58.6 (14.2) | 0.03 | 53.4 (12.1) | 0.05 |
| Male, n (%) | 77 (45.6) | 12 (34.3) | 0.22 | 26 (37.1) | 0.77 |
| White race/ethnicity, n (%) | 139 (82.3) | 20 (57.1) | 0.001 | 42 (60.0) | 0.78 |
| HRCT Pattern, n (%) | |||||
| Usual Interstitial Pneumonia | 65 (38.7) | 5 (14.3) | 0.006 | 15 (21.7) | 0.36 |
| Non-specific Interstitial | |||||
| Pneumonia/Organizing pneumonia | 73 (43.5) | 23 (65.7) | 0.02 | 42 (60.9) | 0.63 |
| SLB Pattern | |||||
| Usual Interstitial Pneumonia | 57 (64.8) | 4 (28.6) | 0.02 | 6 (30.0) | 1 |
| Non-specific Interstitial | |||||
| Pneumonia/Organizing pneumonia | 25 (28.4) | 7 (50.0) | 0.1 | 13 (65.0) | 0.38 |
| Treatment, n (%) | |||||
| Any Immunosuppressant | 63 (37.3) | 26 (74.3) | <0.001 | 62 (88.6) | 0.06 |
| Mycophenolate Mofetil | 37 (21.9) | 19 (54.3) | 39 (55.7) | ||
| Azathioprine | 37 (21.9) | 16 (45.7) | 37 (52.9) | ||
| Cyclophosphamide | 3 (1.8) | 0 (0) | 5 (7.1) | ||
| Rituximab | 1 (0.6) | 1 (2.9) | 7 (10.0) | ||
| Outcomes | |||||
| Death, n (%) | 50 (29.6) | 2 (5.7) | 0.002 | 2 (2.9) | 0.6 |
| Transplant, n (%) | 10 (5.9) | 0 (0) | 0.22 | 1 (1.4) | 1 |
| Death or Transplant, n (%) | 60 (35.5) | 2 (5.7) | <0.001 | 3 (4.3) | 0.75 |
| Follow-up time, median (IQR) | 28.5 (14.4–36.0) | 32.6 (24.2–36.0) | 0.12 | 36.0 (27.6–36.0) | 0.04 |
Abbreviations: IIM = idiopathic inflammatory myopathy; ILD = interstitial lung disease; IPAF = interstitial pneumonia with autoimmune features; MSA = myositis specific antibody; HRCT = high resolution computed tomography; SLB = surgical lung biopsy;