All cases (N=84) | Anti-cHSP60-positive (n=36) | Anti-cHSP60-negative (n=48) | P values | |
Age at assessment, mean±SD (range), years | 44.2±13.4 (22–81) | 41.9±11.6 | 45.9±14.5 | 0.18 |
Disease duration, median (IQR), years | 8 (3–15) | 9.5 (5–15) | 7 (2–14) | 0.31 |
Number of ACR classification criteria fulfilled, median (IQR)* | 6 (5–7) | 6 (5–8) | 6 (5–7) | 0.98 |
Nasopharyngeal ulcers, n (%) | 26/83 (31) | 15 (42) | 11 (23) | 0.097 |
Pericarditis, n (%) | 24/83 (29) | 15 (42) | 9 (19) | 0.03 |
Antiphospholipid antibodies, n (%) | 41/83 (49) | 22 (61) | 19 (40) | 0.077 |
Disease activity at assessment | ||||
SELENA-SLEDAI, median (IQR) | 5 (2–10) | 6 (2–9) | 4.5 (2–12) | 0.68 |
Treatment | ||||
Systemic corticosteroids during the past month, n (%) | 40/77 (52) | 20 (59) | 20 (47) | 0.36 |
High-dose steroids (prednisone >10 mg/day), n (%) | 3/40 (8) | 1 (5) | 2 (10) | 1.00 |
Antimalarial therapy during the past month, n (%) | 55/77 (71) | 26 (77) | 29 (67) | 0.45 |
Immunosuppressant during the past month, n (%)† | 42/77 (55) | 18 (53) | 24 (56) | 0.82 |
Immunosuppressant ever, n (%) | 58 (75) | 27 (79) | 31 (66) | 0.22 |
Damage | ||||
Any thrombotic or ischaemic event, n (%) | 22 (26) | 11 (31) | 11 (23) | 0.46 |
Dialysis or renal transplantation, n (%) | 5 (6) | 4 (11) | 1 (2) | 0.16 |
cHSP60=chlamydial heat-shock-protein-6; SD=SD deviation; IQR=IQR range;
*No significant association found for photosensitivity, malar rash, discoid rash, arthritis, pleuritic, renal disorder, haematological disorder, seizures, psychosis, ANA, antidouble-stranded DNA antibodies and anti-Smith antibodies.
†Mycophenolate mofetil (n=19), azathioprine (n=9), rituximab (n=6), belimumab (n=4), methotrexate (n=4), calcineurin inhibitor (n=2), abatacept (n=1) and tocilizumab (n=1), without significant differences between groups.
ACR, American College of Rheumatology; cHSP60, chlamydial heat-shock protein-6; SELENA-SLEDAI, Safety of Estrogens in Lupus Erythematosus - National Assessment-Systemic Lupus Erythematosus Disease Activity Index.