Table 1.
Demographic characteristics of the patients, ANA status at baseline and characteristics of the infusion reactions
| Characteristic | RA (n = 213) | SpAs (n = 76) |
| Age at inclusion (years) | 55.9 ± 14.0 | 45.0 ± 13.1 |
| Age at disease onset (years) | 43.2 ± 15.2 | 31.9 ± 13.1 |
| Disease duration at start (years) | 12.6 ± 10.0 | 13.1 ± 11.0 |
| Treatment duration at infusion reaction (months) | 11.5 ± 9.6 | 4.3 ± 4.3 |
| Number of previous DMARDs | 3.3 ± 1.7 | 1.9 ± 1.1 |
| Female | 156 (73.2%) | 40 (52.6%) |
| ANA positivity (yes) | 56/201 (27.9%) | 18/72 (25.0%) |
| Infusion reaction (yes) | 45 (21.1%) | 10 (13.2%) |
| Infusion reaction leading to withdrawal of treatment | 33/45 (73.3 %) | 9/10 (90%) |
Values are expressed as mean ± standard deviation or as number (%). ANA, antinuclear antibody; DMARD, disease-modifying antirheumatic drug.