ERYTHROPOIETIN FOR ANEMIA IN HEMODIALYSIS-PATIENTS - RESULTS OF A MAINTENANCE STUDY (THE CANADIAN-ERYTHROPOIETIN-STUDY-GROUP)

Most published studies of recombinant human erythropoietin (rHuEpo) have been of limited duration and in small patient populations. The present study examines the long-term effects of rHuEpo in 98 haemodialysis patients treated for up to 18 months. All patients had completed a 6 month placebo-controlled study of rHuEpo. Patients previously on placebo (group 1; n = 31) received rHuEpo at an initial dose of 50 U/kg thrice weekly with subsequent dose adjustments to maintain haemoglobin (Hb) in the range 105 120 g/l. Patients previously on rHuEpo (group 2; n = 67) continued on their usual dose with adjustments made to maintain Hb at 105-120 g/l. Haematological parameters were measured every 2 weeks. Quality of life, assessed by a disease-specific kidney disease questionnaire (KDQ), was measured every 6 months. Mean Hb in group 1 increased from 74.2 +/- 11.4 g/l at baseline to 1 12.9 +/- 12.6 g/l after 12 months of rHuEpo therapy. After 12 weeks of rHuEpo therapy Hb in groups 1 and 2 was indistinguishable. Hb remained constant in both groups throughout the period of follow-up. Mean rHuEpo dose requirements were similar in both groups. At the end of the study the mean intravenous rHuEpo dose in group 1 patients was 176.6 +/- 154.4 and in group 2 patients was 210.0 +/- 144.0 U/kg per week. Access failure was increased during rHuEpo therapy in patients with synthetic grafts (46% versus 7% failures compared to fistulae; P < 0.001). Group 1 patients receiving rHuEpo had a significant increase in diastolic but not systolic blood pressure despite a 32% increase in overall antihypertensive prescriptions. Group 1 patients experienced an improvement in KDQ scores comparable to that seen in group 2 patients. The improved KDQ scores were maintained throughout the study, indicating a sustained and clinically significant improvement in disease-specific quality of life. It is concluded that prolonged treatment with rHuEpo for the anaemia of chronic renal failure is associated with a sustained improvement in quality of life and an acceptably low morbidity. Patients with synthetic access may be vulnerable to an increased access failure rate and may require a lower target Hb.