Table 1 Characteristics of the two patient cohorts.
Retrospective study | Prospective cohort | |
|---|---|---|
Number of patients (female/male) | 94 (73/14) | 70 (53/17) |
Age at disease onset (years) [mean (range)] | 45.8 (20–77) | 51.9 (19–74) |
Disease duration (years) [mean (range)] | 16.7 (1.4–61) | 4.44 (4.1–6.7) |
ESR (mm/h) [mean (range)] | 34.2 (2–100) | 23.8 (3–76) |
C-reactive protein (mg/l) [mean (range)] | 34.3 (0–190) | 13.1 (0–116.5) |
Patients positive for RF IgM [n (%)] | 51 (54.3) | 42 (60) |
RF IgM concentration (IU/ml) [mean (range)] | 344.6 (0–3680) | 245.2 (0–3430) |
Patients positive for RF IgA [n (%)] | 52 (55.3) | 3 (48.6) |
RF IgA concentration (IU/ml) [mean (range)] | 105.6 (0–600) | 71.8 (0–600) |
Patients positive for ANF [n (%)] | 56 (59.5) | 55 (78.6) |
Extra-articular manifestations | ||
Rheumatoid nodules [n (%)] | 28 (29.8) | 5 (7.1) |
Keratokonjunctivitis sicca [n (%)] | 30 (32) | 10 (14.3) |
Polyserositis [n (%)] | 2 (2.1) | 0 |
Interstitial pulmonary fibrosis [n (%)] | 1 (1.1) | 0 |
Immunogenetics | ||
DRB1*01+ [n (%)] | 21 (22) | 19 (27.1) |
SE+ DR4+ [n (%)] | 46 (49) | 32 (45.7) |
SE+ DR4+ homozygotes [n (%)] | 15 (16.0) | 8 (11.4) |
SE+ [n (%)] | 67 (71) | 51 (72.8) |
SE compound homozygotes [n (%)] | 24 (25.5) | 12 (17.1) |
Therapy | ||
Methotrexate | 57 | 56 |
Cyclosporine A | 9 | 6 |
Azathioprine | 6 | 0 |
Chlorochine/sulfasalazine/gold salts intramuscularly | 6 | 5 |
Cyclophosphamide | 7 | 0 |
No DMARD | 9 | 7 |
Number of DMARD used [mean (range)] | 2 (0–5) | 1 (0–3) |