Effects of subcutaneous recombinant human erythropoietin in patients on continuous ambulatory peritoneal dialysis

The use of recombinant human erythropoietin (rHuEPO) has revolutionized the treatment of renal anemia, but the dose regimens, the optimal frequency, and the effects on other target organs like the central nervous systems (CNS) are still under discussion. We designed a prospective, ongoing study with 10 stable continuous ambulatory peritoneal dialysis (CAPD) patients (6 males, 4 females; mean age 64.4 +/- 7.8 years), with a pretreatment hemoglobin (Hb) < 7.0 g% and requiring regular blood transfusions. Seven patients were treated with 4000 U rHuEPO once weekly (Eritrogen, Boehringer Mannheim), 2 patients received 4000 U every 5 and 8 days, and the last one 4000 U every 10 days. The target hematocrit was 33% and Hb 10.0 g%. The CNS activity was recorded as visual (VEP), brainstem (BAER), and somatosensory (SEP)-evoked potentials. The mean Hb concentration increased from 6.9 +/- 1.2 g% to 10.3 +/- 1.6 g% (p < 0.001) over 8 weeks. There were no significant changes in urea, creatinine, and potassium levels, and urine output. rHuEPO induced a decrease in latency of P100 VEP, in the four main components of BAER, and in the P27-N35 intertime of SEP. Parallel to the improvement of red cell indices, patients experienced a dramatic improvement in well-being. The subcutaneous administration of a single vial of rHuEPO is safe, convenient, and inexpensive in CAPD. The role of rHuEPO treatment in improving the electrophysiological brain function in uremic and anemic patients remains to be studied and may not necessarily be based on improved cerebral oxygenation.