Effect of high‐flux dialysis on the anaemia of haemodialysis patients

Dialysis dose ( Kt/V ) remained constant in both groups (from 1.30±0.17 to 1.33±0.20 in the conventional Background. Anaemia is one of the major clinical group and from 1.28±0.26 to 1.26±0.21 in the expericharacteristics of patients with chronic renal failure, mental group, P=0.242). Median pre- and postand has a considerable effect on morbidity and mortal- dialysis b 2 -microglobulin levels remained constant in ity. Adequate dialysis is of paramount importance in the conventional group (31.9 and 34.1 mg/dl at basecorrecting anaemia by removing small and medium- line) and decreased in the experimental group (presized molecules, which may inhibit erythropoiesis. dialysis values from 31.1 to 24.7 mg/dl, P=0.004 and However, high-molecular-weight inhibitors cleared post-dialysis values from 24.8 to 20.8 mg/dl, P= only by means of highly porous membranes have also 0.002). Median erythropoietin doses were not different been found in uraemic serum and it has been claimed at baseline (70 IU/kg/week in conventional treatment from uncontrolled studies that high-flux dialysis could and 90 IU/kg/week in experimental treatment, P= improve anaemia in haemodialysis patients. 0.628) and remained constant during follow-up (from Methods. We therefore planned this multicentre ran- 70 to 69 IU/kg/week in the conventional group and domized controlled trial with the aim of testing whether from 90 to 91 IU/kg/week in the experimental group, the use of a large-pore biocompatible membrane for a P=0.410). Median erythropoietin plasma levels were fixed 12-week follow-up improves anaemia in haemo- in the normal range and remained constant (from 12.1 dialysis patients in comparison with the use of a to 12.9 mU/ml in the conventional group and from conventional cellulose membrane. Eighty-four (5.3%) 13.2 to 14.0 mU/ml in the experimental group, P= of a total of 1576 adult haemodialysed patients 0.550). attending 13 Dialysis Units fulfilled the entry criteria Conclusions. This study showed no difference in haeand were randomly assigned to the experimental treat- moglobin level increase between patients treated for 3 ment (42 patients) or conventional treatment (42 months with a high-flux biocompatible membrane in patients). comparison with those treated with a standard memResults. Haemoglobin levels increased non- brane. When patients are highly selected, adequately significantly from 9.5±0.8 to 9.8±1.3 g/dl (P=0.069) dialysed, and have no iron or vitamin depletion, the in the population as a whole, with no significant effect of a high-flux membrane is much less than might difference between the two groups (P=0.485). be expected from the results of uncontrolled studies. Erythropoietin therapy was given to 32/39 patients Keywords: anaemia; biocompatibility; biocompatible (82%) in the conventional group, and 26/35 (74%) in membrane; cellulose membrane; high-flux haemodiathe experimental group (P=0.783) with subcutaneous lysis; b 2 -microglobulin administration to 26/32 patients in conventional and to 23/26 patients in experimental group, P=0.495.