Low dose intravenous ascorbic acid for erythropoietin-hyporesponsive anemia in diabetic hemodialysis patients with iron overload.

BACKGROUND: Recent report demonstrates that inadequate iron mobilization and defective iron utilization may cause recombinant erythropoieitin (rEPO) hyporesponsiveness in hemodialysis (HD) patients with iron overload. The effect of intravenous ascorbic acid (IVAA) in HD patients selected on the basis of iron overload and EPO resistance also has been proven. However, it is uncertain whether IVAA still works in diabetic ESRD patients with hyperferritinemia. Therefore, the aim of this study focusing on diabetic ESRD patients was to analyze the potential effect of low dose IVAA on improvement of anemia and erythropoiesis-related parameters when compared with control period.

PATIENTS AND METHOD: This study consisted of 22 chronic hemodialysis patients with type II diabetes in a single dialysis unit. In studies of this type, all eligible patients are followed up, but the primary comparison is still between different sequentially treatment including control period and post-IVAA period in same patients. IVAA patients received ascorbic acid, 100 mg each administered intravenously three times per week for eight weeks of treatment and four months of post-treatment follow-up.

RESULTS: The demographic characteristics of 22 diabetic uremic patients show that mean age is 63.6 +/- 10.2 years old. The ratio of sex (M/F) = 10/12. Mean duration of HD is 46.7 +/- 33.2 months. As for the urea kinetic study between these two periods including KT/V, nPCR, and URR, there is no significantly different. As for anemia-related parameters, Hb and Hct increased significantly in post-IVAA period after 3 months compared with control period, while MCV did not increase significantly. Serum ferritin significantly decreased at study completion. The same situation is for iron. As for TS, it significantly increased at one month and further markedly increased at subsequent three months.

CONCLUSION: This study has demonstrated that short-term low dose IVAA therapy can facilitate iron release from reticuloendothelial system but also increase iron utilization in diabetic hemodialysis patients with iron overload. Therefore, IVAA is a potential adjuvant therapy to treat erythropoeitin-hyporesponsive anemia in iron-overloaded patients.