Oral Vitamin C Administration on Erythropoietin Dosing Requirement in End-Stage Renal Disease Patients on Regular Hemodialysis

Erythropoietin deficiency is the most significant cause of anemia in chronic kidney disease (CKD) and has been demonstrated to occur at each stage of kidney failure. Because the kidney is the sole source of erythropoietin (EPO) synthesis in adults, reduction in kidney mass as occurs in progressive CKD often results in impairment of EPO production, resulting in anemia.

Vitamin C deficiency can interfere with iron absorption and utilization, as well as lead to various abnormalities. The occurrence of widespread vitamin C deficiency in dialysis patients calls for greater attention to these clinical problems. Ascorbic acid is low in patients with advanced CKD and end-stage renal disease (ESRD) due to dietary restrictions on vitamin C-rich foods, as these foods are usually also rich in potassium.

Inclusion criteria

• Age >18 years.
• Both sexes.
• Stable hemodialysis (HD) for 90 days or more
• Hemoglobin (HB) levels of 9-11 g/dL (as Hb levels above 11 g/dL, Epo dose reduction is recommended irrespective of iron level).
• Erythropoietin (EPO) dose ≥4000 U/HD session and unchanged dose for two consecutive months
• Ferritin level >100 mcg/L.
• Transferrin saturation (Tsat) of <30 %.
• Not on a vitamin C supplement.
• Not receiving iron supplementation in the preceding 2 months. Each patient's previous 2-month stable dose of Epo was taken as the control.

Exclusion criteria

• Patients with gastrointestinal bleeding.
• Blood transfusion, malignancy.
• Hospital admission or history of noncompliance with dialysis and/or medication were excluded from the study and were also censored if these events occurred during the study period.