Anti-oxidized low-density-lipoprotein (OxLDL) antibodies in systemic lupus erythematosus with and without antiphospholipid syndrome

The aim of this study was to examine potential links between antiOxLDL antibodies and the clinical and biological features of secondary antiphospholipid syndrome (II APLS) associated with systemic lupus erythematosus (SLE). A cohort study was done of 98 SLE patients followed-up for 1 y, including 18 with definite II APLS and 13 patients with definite primary APLS (I APLS). IgG anticardiolipin, IgG anti beta2 GPI, lupus anticoagulant, VDRL and IgG antiOxLDL were measured in all 98 study subjects. High antiOxLDL titers were found in seven (39%) of the 18 patients with II APLS vs 10 (12.5%) of the 80 patients without APLS (P < 0.01; OR = 4.45; 95% CI = 1.4-14.1) and none of the 13 patients with I APLS (P < 0.02). The mean antiOxLDL titer was not significantly higher in the SLE patients with than without II APLS (P > 0.05). A high antiOxLDL titer was correlated with deep venous thrombosis (P < 0.01; OR = 5.77; 95% CI = 0.54-61) but not with arterial thrombosis (P > 0.05; OR = 1; 95% CI = 0.29-3.09), thrombocytopenia, central nervous system involvement, livedo reticularis, or a positive Coombs test. The antiOxLDL antibody titer was correlated with the IgG anticardiolipin antibody titer (r = 0.235; P = 0.02) and with the IgG anti-beta2 GPI antibody titer (r = 0.224; P = 0.026). AntiOxLDL elevation was found in 17% of SLE patients and was significantly associated with II APLS and venous thrombosis. We found no evidence suggesting that antiOxLDL may be associated with atherosclerosis.