Oral ascorbic acid may decrease the amount of darbepoetin required by hemodialysis (HD) patients with functional iron deficiency, according to study findings presented at the National Kidney Foundation’s 2014 Spring Clinical Meetings in Las Vegas.
A research team led by Anil Saxena, MD, of Mafraq Hospital in Abu Dhabi, United Arab Emirates, enrolled 79 HD patients suffering from anemia with functional iron deficiency. They randomized 40 patients to receive ascorbic acid 1,000 mg 3 times per week and 39 to receive standard care (control arm). Subjects had hemoglobin levels of 10 mg/dL or less, serum ferritin level of 500 ng/mL or higher, and C-reactive protein (CRP) level of 5.0 mg/mL.
At 48 weeks, the darbepoietin weekly dose was significantly lower in the ascorbic acid group than in the control group (1.31 vs. 3.87 μg/kg every 4 weeks). The ascorbic acid group had significantly higher mean hemoglobin (12.83 vs. 8.8 g/dL) and tranferrin saturation (39.9% vs. 15.7%) and significantly lower ferritin levels (59.6 vs. 709.6 ng/mL) and CRP levels (1.9 vs. 19.9 mg/dL) than controls.
Ascorbic acid is an antioxidant that enhances absorption of iron from the gut, the researchers explained. It also mobilizes iron from tissues and acts as a maturation factor for red blood cells.