Lowering the Erythropoietin Requirement for Dialysis Patients with Functional Iron Deficiency Using Ascorbic Acid (Vitamin C)

Abstract

AbstractBACKGROUNDHemodialysis patients with functional iron deficiency often require excess recombinant human erythropoietin (EPO). In a few small studies, ascorbic acid (AA) has been shown to reduce EPO requirements. The goal of this study was to determine the lowest effective and safe dose of AA for these patients.METHODSThis was an open‐labeled, prospective, single‐center study involving hemodialysis patients with serum ferritin >500 ng/mL and transferrin saturation <20%. Patients with C‐reactive protein (CRP) >2 mg/dL were excluded. The study comprised of 4 consecutive phases: intravenous AA 100 mg (phase I), 200 mg (phase II), 300 mg (phase III), and oral AA 250 mg (phase IV). Oxalate and AA levels were obtained before and after each treatment phase.RESULTSA total of 8 patients were enrolled and 6 patients completed the study. Positive impact of AA supplementation on lowering the EPO requirement was mainly seen with the 300 mg dosage and maintained on oral supplementation. Neither the oxalate nor AA levels increased significantly during the study. Overall the patients tolerated both forms of ascorbic acid well.CONCLUSIONThe role of AA in reducing the EPO requirement appears promising. Larger studies are needed to examine the safety and confirm the efficacy of AA in these patients.