Effect of 1-year oral α-tocopherol administration on anticardiolipin antibodies in hemodialysis patients

Background. Anticardiolipin antibodies (ACA) have been related to an increased incidence of thrombotic episodes and atherosclerosis progression. ACA levels are elevated in hemodialysis (HD) patients. Atheroembolic episodes are the major cause of morbidity and mortality in this population. Oxidative stress has been implicated in ACA formation, and it is increased in HD patients. Vitamin E is a known antioxidant factor. In this study, the effects of prolonged oral alpha-tocopherol administration on ACA levels were evaluated. Methods. Serum anticardiolipin IgG antibodies (ACA-IgG) and IgM antibodies (ACA-IgM) levels were evaluated in 27 stable HD patients and 22 healthy volunteers. Then measurements were performed in the patients' group after oral administration of a-tocopherol at a dose of 500 mg/d for a 1-year period. ACA levels were assessed by solid-phase enzyme immunoassay. Results. ACA-IgG levels were higher in HD patients compared with control (13.3 +/- 6.64 GPL/mL vs. 7.727 +/- 18.305 GPL/mL, p < .001). This was not the case for ACA-IgM levels (2.96 +/- 4.18 MPL/mL vs. 1.386 +/- 2.636 MPL/mL, p=.17). alpha-Tocopherol administration resulted in a further increase in ACA-IgG (26.7 +/- 14.7 GPL/mL vs. 13.3 +/- 6.64 GPL/mL, p <.001) and ACA-IgM levels (8.17 +/- 1.95 MPL/mL vs. 2.96 +/- 4.18 MPL/mL, p <.001) in HD patients. Conclusions. Prolonged oral a-tocopherol administration in HD patients increases ACA levels. The mechanism and the clinical significance of this finding need further evaluation.