A Randomized, Controlled Trial of the Effects of Adding Vitamin B12 and Folate to Erythropoietin for the Treatment of Anemia of Prematurity

BACKGROUND: Premature infants, especially those with birth weights of <1500 g, often suffer from anemia of prematurity and associated problems. Erythropoietin therapy is a safe effective way to prevent and to treat anemia of prematurity. We hypothesized that combined administration of vitamin B12 and folate with erythropoietin and iron would enhance erythropoietin-induced erythropoiesis. METHODS: In a randomized, controlled trial, 64 premature infants (birth weight: 801-1300 g) receiving erythropoietin and iron supplementation were assigned randomly to receive either vitamin B12 (3 microg/kg per day) and folate (100 microg/kg per day) (treatment group) or a lower dose of folate (60 microg/kg per day) (control group). RESULTS: During the 4-week observation period, vitamin B12 and folate enhanced erythropoietin-induced erythropoiesis significantly, as indicated by a 10% increase in red blood cell counts, compared with folate alone. Hemoglobin and hematocrit levels remained stable in the treatment group, whereas they decreased in the control group. Vitamin B12 levels in the treatment group increased over baseline and control values, whereas red blood cell folate levels were comparable between the groups. Subsequent analysis showed slight nonsignificant differences in baseline red blood cell count, hemoglobin level, hematocrit level, and mean corpuscular volume values, which must be addressed as a limitation. CONCLUSIONS: With the limitation of a slight imbalance in baseline data between the study groups, combined therapy with vitamin B12, folate, erythropoietin, and orally and intravenously administered iron seemed more effective in stimulating erythropoiesis among premature infants, compared with erythropoietin, iron, and low-dose folate alone. Additional trials are necessary to confirm these data.