Clinical characteristics of the study population
| IFX-treated patients (n=250) | Median age (IQR 25–75, range) | 52.5 (42–63, 21–82) | |
| Sex | Male | 39.8% | |
| Female | 60.2% | ||
| Disease | Rheumatoid arthritis | 43.5% | |
| Spondyloarthritis | 56.5% | ||
| Mean IFX therapy, years (IQR 25–75, range) | 4.9 (1.8–7.8, 0.3–13.8) | ||
| ATI status | Positive | 49.6% | |
| Negative | 50.4% | ||
| Concomitant immunosuppressives | No | 23.1% | |
| Methotrexate | 56.5% | ||
| Others* | 20.4% | ||
| Controls (IFX-naïve) (n=77) | Rheumatic patients | 48.0% | |
| Anti-adalimumab antibody-positive rheumatic patients | 24.7% | ||
| Healthy individuals | 27.3% | ||
*Other concomitant immunosuppressives were sulfasalazine, prednisone, leflunomide, azathioprine and hydroxychloroquine alone or in combination.
ATI, antibodies to IFX IFX, infliximab.