Efficacy and safety of oral versus intravenous vitamin C in hemodialysis patients with functional iron deficiency

ABSTRACT

Hemodialysis patients [HD] with functional iron deficiency[FID] often develop resistance to recombinant human erythropoietin [rHuEpo]. Recent studies suggest that intravenous ascorbic acid [IVAA] may circumvent rHuEpo resistance, while oral [AA] is readily attainable. The aim of this study was to evaluate efficacy and safety of oral versus intravenous vitamin C on FID and whether this can improve anemia in hemodialysis patients. In this study, 31 hemodialysis patients with serum ferritin >100 micro g/L, transferin saturation [TS] < 30% and Hb <11g/dL were selected and randomly divided into the oral and IV groups. The IVAA group received vitamin C 1.5 g, administered weekly and the oral group, 125 mg vitamin C daily for two months. Hb, ferritin, serum iron, Tsat and serum oxalate were measured at the beginning of the study and 2 months later. Independent - sample T-Test were used for intergroup comparison. P value < 0/05 was considered significant. Mean Hb difference was 1.1 +/- 0.7g/dL in the oral and 0.1 +/- 1g/dL in the IVAA group, being significantly higher in the oral group [p=0.02]. There were no significant differences between the two groups in the delta means of ferritin and Tsat [p=0.5, p=0.3]. Delta means of serum oxalate in the 2 groups were 0.05 +/- 0.4mg/L, and 0.1 +/- 0.3mg/L respectively, difference not significant [p=0.3]. Oral AA significantly increased Hb in HD patients suffering from FID. Considering the feasibility and cost-effectiveness, clinicians could consider oral instead IVAA in rHuEpo hyporesponsive patients undergoing HD