Table 1. Demographic, immunological and clinical parameters of the RA patients.
| RA patients | IFNα | ||
| (n = 120) | IFNlow (n = 80) | IFNhigh (n = 40) | |
| Sex (female/male) | 101/19 | 70/10 | 31/9 |
| Age at sampling, years | 55.33±15.23 | 55.24±15.04 | 55.56±16.00 |
| Age at diagnosis, years | 53.09±18.00 | 52.78±14.97 | 53.77±16.23 |
| Disease duration, months | 21.02±20.50 | 23.33±20.83 | 16.00±19.26 |
| Clinical features | |||
| Number of tender joints | 5.24±5.25 | 4.29±5.59 | 6.86±7.00 |
| Number of swollen joints | 2.50±3.31 | 1.83±3.15 | 3.64±3.38 |
| Patient global assessment (0–100) | 32.05±23.63 | 28.13±25.20 | 38.79±19.69 |
| Pain of patient’s assessment (0–10) | 3.21±2.42 | 2.71±2.40 | 4.07±2.30 |
| Duration of morning stiffness, min | 48.42±70.93 | 46.25±78.30 | 52.14±58.72 |
| DAS28 | 3.81±1.61 | 3.35±1.52 | 4.59±1.49* |
| HAQ | 0.77±0.70 | 0.68±0.70 | 0.95±0.67 |
| CRP, mg/dl | 0.39±0.63 | 0.28±0.45 | 0.59±0.83 |
| ESR, mm/h | 23.47±19.94 | 16.87±10.64 | 34.78±26.71* |
| RF positivity, n (%) | 68 (56.7) | 36 (45.0) | 32 (80.0)*** |
| Anti-CCP positivity, n (%) | 69 (57.5) | 36 (45.0) | 33 (82.5)*** |
| ANA positivity, n (%) | 46 (38.3) | 25 (31.2) | 21 (52.5)* |
| Smoking habit, n (%) | 49 (40.8) | 32 (40.0) | 17 (42.5) |
| Hypertension, n (%) | 30 (25.0) | 19 (23.7) | 11 (27.5) |
| Hypercholesterolemia, n (%) | 11 (9.1) | 8 (6.6) | 3 (2.5) |
| Diabetes mellitus, n (%) | 15 (12.5) | 8 (10.0) | 7 (17.5) |
| Treatments n (%) | |||
| None or NSAIDs | 19 (15.8) | 10 (10.1) | 9 (22.5) |
| Glucocorticoids | 58 (48.3) | 40 (50.0) | 18 (45.0) |
| Methotrexate | 79 (65.8) | 57 (71.3) | 22 (55.0) |
| Leflunomide | 16 (13.3) | 11 (13.7) | 5 (12.5) |
| TNF-α blockers | 26 (21.6) | 14 (17.5) | 12 (30.0) |
| Cardiovascular events, n(%) | |||
| Cardiovascular events | 27 (22.5) | 12 (15.0) | 15 (37.5)** |
| Ischemic heart disease | 10 (8.33) | 4 (5.0) | 6 (15.0) |
| Cerebrovascular accidents | 4 (3.33) | 2 (2.5) | 2 (5.0) |
| Heart failure | 12 (10.0) | 6 (7.5) | 6 (15.0) |
| Peripheral arteriopathy | 1 (0.83) | 0 (0.0) | 1 (2.5) |
Data of the whole RA patients group and classified according to IFNα serum levels. Data are expressed as (mean ± SD) unless otherwise was stated. Differences between categorical variables were evaluated by chi-square test, whereas Mann-Withney U test was used for continuous ones. *p<0.05, **p<0.01, ***p<0.001. IFNlow: serum levels <90th percentile in HC (4.092 pg/ml); IFNhigh: serum levels ≥90th percentile in HC.