Long-term use of vitamin E-coated polysulfone membrane (VECM) dialysis filters may significantly improve hemoglobin levels and reduce requirements of erythropoietin (EPO), according to an Italian study.
“Vitamin E has long been known for its antioxidant properties, but oral vitamin E has not been helpful in treating dialysis-related anemia,” said lead investigator Dinna Cruz, MD, clinical instructor of nephrology at San Bartolo Hospital in Vicenza. “We were gratified to see that the use of newer vitamin E-coated filters, which were designed to reduce oxidative stress, had visible clinical benefits. Our patients’ red blood cell counts improved within the first six months, and they needed much lower doses of synthetic EPO.” The filters, already used in Europe, are not yet available in the United States.
In recent years, she said, a growing body of scientific evidence has shown that oxidative stress plays a key role in the genesis and severity of dialysis anemia. Vitamin E reduces lipid peroxidation and inhibits generation of reactive oxygen species.
In the study, 172 hemodialysis patients (mean age 65.4 years) were switched from a biocompatible membrane to VECM. The investigators measured hemoglobin (Hb) and EPO doses at baseline and at four, eight, and 12 months and calculated the modified EPO index as EPO (dose per week)/Hb. The values at four, eight and 12 months were compared with baseline values.
At 12 months, the average dose of synthetic EPO had decreased by about 23%. Mean Hb levels increased significantly at all time points. The EPO index decreased significantly from 735 U/wk/Hb as early as four months (665.5 from 735.3 U/wk/Hb) to a final value of 567.7 U/wk/Hb at 12 months. The percentage of patients who reached an Hb of 11 g/dL or greater increased from 49.4% to 79.7% after 12 months.
“We saw almost a doubling of patients reaching their KDOQI targets for hemoglobin within a year,” Dr. Cruz said. “There may be several good effects that come from reducing oxidative stress in this way. If it had this good of an effect on anemia, we should also look at the effects on infections and mortality. This is another promising approach to anemia in hemodialysis patients.”