Giving Vitamin B6 Ups Resistance to ESAs
New finding on vitamin B6 is the opposite of what investigators hypothesized.
PHILADELPHIA—Vitamin B6 supplementation may increase resistance to erythropoiesis-stimulating agents (ESAs) in hemodialysis (HD) patients, according to study findings presented at the 2014 Kidney Week meeting.
In a poster presentation, investigators Yoshitsugu Obi, MD, PhD, and collaborators at Osaka University Graduate School of medicine in Japan, noted that ESA resistance is a risk factor for cardiovascular events and death in HD patients and vitamin B6 deficiency, which may cause sideroblastic anemia, is common in this population. They conducted a randomized trial to determine whether vitamin B6 supplementation could decrease the ESA resistance index (ERI).
They screened 231 prevalent HD patients and calculated their ERIs. After excluding patients with iron deficiency, they enrolled 60 patients with ERIs above the median.
The researchers randomly assigned patients to receive vitamin B6 (60 mg of intravenous pyridoxal phosphate after earch thrice-weekly HD session) or a control group. The primary outcome was a change in ERI from baseline to the 12th week.
The mean baseline ERI was 9.5 and 10.1 IU/kg per g/dL in the control and vitamin B6 groups, respectively. Fifty-three patients completed the study. Contrary to the investigators' hypothesis, the vitamin B6 group showed a significant mean ERI increase of 2.4 IU/kg per g/dL at the 12th week versus the control group.
In a separate study presented at the conference, researchers at the University of Texas Health Science Center in San Antonio found that ergocalciferol supplementation in HD patients with vitamin D deficiency did not decrease their ESA requirement.