Background and aims Patients with systemic lupus erythematosus (SLE) and antiphospholipidsyndrome (APS) are at increased risk of atherosclerosis, and occurs much earlier compared to the general population even after accounting for traditional risk factors. Aim of the work: To examine the association between serum TWEAK, leptin and subclinical atherosclerosis in SLE and APS.

Patients and methods Serum tumour necrosis factor (TNF)-like weak inducer of apoptosis(TWEAK) and leptin were measured in 30 SLE patients, 26 SLE patients with secondary APS(SLE–APS), 14 with primary APS (pAPS) and 20 age and sex matched control. The SLE diseaseactivity index (SLEDAI) was assessed in SLE patients. The intima media thickness (IMT) was measuredby carotid ultrasound.

Results Serum TWEAK was significantly higher in patients with pAPS (945.1±16.2 pg/ml) than in SLE–APS (755.3±59.9 pg/ml), SLE patients (499.2±47.1 pg/ml) and control(129.6±18.6 pg/ml) (p<0.001). Also, serum leptin was significantly higher in pAPSpatients (14.0±2.8 ng/ml) compared to that in SLE–APS (6.5±0.9 ng/ml), SLE patients (3.8±1.2 ng/ml) and control (1.6±0.6 ng/ml) (p<0.001). The IMT was significantly increasedin the pAPS patients compared to SLE–APS group (p<0.001), SLE patients (p=0.006) and to the control (p<0.001). A significant correlation was found between TWEAK with the body massindex and high density lipoprotein in SLE–APS and inversely with the random blood sugar and thediastolic blood pressure in SLE patients. Serum leptin only significantly correlated with the totalleucocytic count in SLE patients.

Conclusions Patients with pAPS are more liable to develop premature atherosclerosis even in theabsence of the traditional risk factors.