Frequency of autoantibodies in clusters, n (%).
| Autoantibody | Cluster 1, n = 83 | Cluster 2, n = 271 | Cluster 3, n = 170 | Cluster 4, n = 175 | Cluster 5, n = 153 |
|---|---|---|---|---|---|
| Anti-dsDNA | 0 (0.0) | 271 (100)* | 91 (53.5) | 130 (74.3) | 109 (71.2) |
| Anti-Sm | 0 (0.0) | 0 (0.0) | 159 (93.5)* | 3 (1.7) | 1 (0.65) |
| aCL IgG/IgM | 0 (0.0) | 0 (0.0) | 52 (30.5) | 162 (92.5)* | 33 (21.5) |
| LAC | 0 (0.0) | 0 (0.0) | 16 (9.4) | 65 (36.5)* | 11 (7.18) |
| Anti-RNP | 0 (0.0) | 0 (0.0) | 131 (100.0)* | 0 (0.0) | 0 (0.0) |
| Anti-Ro | 0 (0.0) | 0 (0.0) | 53 (31.1) | 2 (1.1) | 153 (98)* |
| Anti-La | 0 (0.0) | 0 (0.0) | 20 (11.8) | 1 (0.57) | 70 (45.7)* |
↵* Significantly different from the 4 other clusters, p < 0.001. Ig: immunoglobulin; LAC: lupus anticoagulant; aCL: anticardiolipin antibody.