Cluster analysis: autoantibody frequencies.
| Autoantibody | Cluster 1, n = 68 (%) | Cluster 2, n = 30 (%) | Cluster 3, n = 58 (%) | p |
|---|---|---|---|---|
| Anti-dsDNA | 42 (61.2) | 26 (86.7) | 51 (87.9) | < 0.001 |
| Antichromatin | 19 (27.9) | 21 (70.0) | 26 (44.8) | < 0.001 |
| Antiribosomal P | 5 (7.4) | 16 (53.3) | 14 (24.1) | < 0.0001 |
| Anti-U1RNP | 0 (0.0) | 25 (83.3) | 55 (94.8) | < 0.0001 |
| Anti-Sm | 0 (0.0) | 15 (50.0) | 51 (87.9) | < 0.0001 |
| Anti-SSA(Ro) | 12 (17.7) | 30 (100.0) | 20 (34.5) | < 0.0001 |
| Anti-SSB(La) | 5 (7.4) | 21 (70.0) | 0 (0.0) | < 0.0001 |
| Antitopoisomerase I | 8 (11.8) | 9 (30.0) | 6 (10.4) | 0.03 |
| Lupus anticoagulant | 11 (16.2) | 4 (13.3) | 8 (13.8) | NS |
| Anticardiolipin | 31 (45.6) | 17 (56.7) | 38 (65.5) | NS |
NS: not statistically significant.