AB0415 The Effect of Vitamin D Supplementation on Antiphospholipid Antibodies Level in Patients with Antiphospholipid Syndrome

BackgroundVitamin D is regarded as modulator of the immune response [1]. Treatment with 1,25(OH)2D can ameliorate autoimmune disorders in rodent models of experimental allergic encephalitis, nephritis, inflammatory bowel disease, and diabetes mellitus [2,3]. Vitamin D deficiency is common among patients with antiphospholipid syndrome (APS) and is associated with clinically defined thrombotic events [4].ObjectivesTo evaluate the effects on antiphospholipid antibodies level of an oral Cholecalcipherol supplementation for 3 months in APS patients.MethodsThe study included 16 patients (men - 4, women - 12) with APS (Sidney, 2006) mean age 34±6,4 years treated with warfarin – 5,0–7,5 mg/day and acetylsalicylic acid – 75 mg/day. 3 patients were diagnosed with vitamin D insufficiency, 13 – with deficiency [5]. Cholecalciferol - 1000 IU/day was added to the therapy for 3 months. Anticardiolipin (aCL) and anti-β2-glycoprotein I (aβ2GPI) IgG and IgM antibodies, serum 25(OH)D level were tested using commercially available ELISA kits before and after treatment with Cholecalciferol. Lupus anticoagulant was not investigated due to possibility of false positive results in warfarine-treated patients.ResultsBaseline level of aCL IgG was median 6,21 intarquartile range 2,72–65,77 GPL, aCL IgM – 85,30 (12,66–154,26) MPL, aβ2GPI IgG –16,40 (7,99–44,32) U/ml, aβ2GPI IgM – 15,89 (6,24–67,60) U/ml, serum 25(OH)D - 15,04 (13,00–19,00) ng/ml. After treatment with Cholecalciferol for 3 months the levels of antiphospholipid antibodies and vitamin D were the following: aCL IgG – 4,69 (2,91–12,42) GPL, aCL IgM – 7,38 (4,42–110,35) MPL, aβ2GPI IgG – 9,43 (5,42 - 13,04) U/ml, aβ2GPI IgM – 29,97 (8,13–71,30) U/ml, serum 25(OH)D - 27,16 (23,06–32,90) ng/ml. We found significant increase in serum 25(OH)D level (p=0,007) and decrease in aβ2GPI IgG level (p=0,038) after treatment with Cholecalciferol. The level of other antiphospholipid antibodies did not differ significantly (p>0,05) before and after Cholecalciferol treatment.ConclusionsOur preliminary results indicate that vitamin D supplementation might be associated with decreased serum aβ2GPI IgG level. This can indicate a possible correlation between vitamin D status and thrombotic risk in APS.ReferencesArnson Y, Amital H, Shoenfeld Y. Vitamin D and autoimmunity: new aetiological and therapeutic considerations. Ann Rheum Dis 2007;66:1137–1142.Penna G, Amuchastegui S, Laverny G, Adorini L. Vitamin D receptor agonists in the treatment of