Clinical characteristics of the study populations
| Characteristic | RA cohort | Non-RA cohort |
|---|---|---|
| No of cases | 288 | 636 |
| Total no of observations | 913 | 2541 |
| Women (%) | 77.1 | 97.6 |
| Age, median (IQR)* | 51 (39–61) | 32 (28–37) |
| Disease duration, median (IQR) | 4.5 (1–10.9) | |
| Erosive disease (%) | 62.5 | |
| Presence of autoantibodies (%) | ||
| ACPA | 64.2 | |
| RF | 77.2 | |
| HLA-DRB1 shared epitope (%) | ||
| 1 copy | 49.4 | |
| 2 copies | 13.5 | |
| FGB −455G>A (%) | ||
| 1 copy | 34.7 | 35.2 |
| 2 copies | 6.9 | 5.8 |
| FGA T312A (%) | ||
| 1 copy | 38.2 | 39.1 |
| 2 copies | 4.9 | 9.3 |
| F13A V34L (%) | ||
| 1 copy | 43.4 | 36.5 |
| 2 copies | 8.7 | 8.0 |
↵* RA patients: age at disease onset; non-RA patients: age at first presentation.
ACPA, anticitrullinated protein antibodies; F13A, factor XIIIA; FGA, α-fibrinogen; FGB, β-fibrinogen; RA, rheumatoid arthritis; RF, rheumatoid factor.