The effects of vitamin E-coated dialysis membranes on serum paraoxonase activity in hemodialysis patients

Background: Hemodialysis patients are exposed to oxidative stress, which can lead to several complications. We therefore sought to evaluate the effect of using vitamin E-coated dialysis membranes for a period of 3 months on serum paraoxonase activity and oxidative stress markers. Methods: Twenty patients and 25 healthy controls were included in this study. Hemodialysis patients were evaluated before and after 3 months of treatment with vitamin E-coated dialysis membranes. Plasma malondialdehyde (MDA) levels, as well as the oxidizability of red blood cells (RBCs) and apolipoprotein B-containing lipoproteins (expressed as RBC-MDA and Delta MDA, respectively) were determined in order to investigate the patients' oxidative status. Plasma vitamin E and vitamin C levels, serum total carotenoid levels and paraoxonase activity were measured to investigate the patients' antioxidative defenses. Results: After 3 months of treatment with vitamin E-coated membranes, vitamin E levels were significantly increased and the oxidizability of RBCs was significantly reduced in the hemodialysis patients. However, there were not any differences from baseline in serum paraoxonase activity, plasma MDA levels or the oxidizability of apolipoprotein B-containing lipoproteins in these patients. Conclusions: Despite promising improvements in vitamin E levels and the oxidizability of RBCs, the results of this study do not support a satisfactory antioxidative effect of vitamin E-coated dialysis membranes. Further studies are needed to identify antioxidative treatments for hemodialysis patients.