Effects Of Erythropoietin Therapy Research Articles

Effects of erythropoietin therapy on the lipid profile in end-stage renal failure

To evaluate the effects of erythropoietin (EPO) therapy on the lipid profile in end-stage renal failure, we undertook a prospective study in patients on both hemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD). One hundred and twelve patients (81 HD, 31 CAPD) were enrolled into the study. Lipid parameters [that is, total cholesterol and the LDL and HDL subfractions, triglycerides, lipoprotein (a), apoproteins A and B], full blood count, iron studies, B12, folate, blood urea, aluminium and serum parathyroid hormone were measured prior to commencement of EPO therapy. Ninety-five patients were reassessed 5.2 +/- 0.3 (mean +/- SEM) months later and 53 patients underwent a further assessment 13.1 +/- 0.6 months after the commencement of EPO, giving an overall follow-up of 10.0 +/- 0.6 months in 95 patients. As expected, EPO treatment was associated with an increase in hemoglobin (7.7 +/- 0.1 vs. 9.9 +/- 0.2 g/dl; P < 0.001) and a decrease in ferritin (687 +/- 99 vs. 399 +/- 69 micrograms/liter; P < 0.01). A significant fall in total cholesterol occurred (5.8 +/- 0.1 vs. 5.4 +/- 0.2 mmol/liter; P < 0.05) in association with a fall in apoprotein B (1.15 +/- 0.04 vs. 1.04 +/- 0.06; P < 0.05) and serum triglycerides (2.26 +/- 0.14 vs. 1.99 +/- 0.21; P < 0.05) during the course of the study. Other lipid parameters did not change, although there was a trend towards improvement.(ABSTRACT TRUNCATED AT 250 WORDS)

Modulation of platelet cytosolic calcium during erythropoietin therapy in uraemia.

Erythropoietin therapy for uraemic anaemia is associated with a high rate of hypertensive and thrombotic complications. The mechanism is unknown, but a change in cellular calcium control may be relevant to changes in blood pressure and thrombosis. Platelets were utilized as a model of vascular smooth muscle cells. The effects of erythropoietin therapy on platelet cellular calcium, assessed by fura-2, were measured in 25 patients receiving renal replacement therapy during a 6-month treatment period. Three patients failed to reach a target haemoglobin and were excluded from the analysis. Blood pressure increased in 11 of the remaining 22 subjects, eight requiring an increase in antihypertensive medication. There were no differences in cellular calcium control between the group in whom blood pressure rose and patients with stable blood pressure. Overall there was a fall of 24% in resting cytosolic calcium (baseline 69.2 +/- 5.1 to 52.5 +/- 3.0 nmol/l, P < 0.05) after 3 months of erythropoietin therapy. There was no change in the thrombin-stimulated peak response in the presence of extracellular calcium during therapy, although thrombin-stimulated intracellular release also fell at 3 months (baseline 769 +/- 61 versus 3 months 559 +/- 49 nmol/l, P < 0.01). This study suggests that intracellular free calcium control within platelets improves in response to erythropoietin therapy. However these changes appear not to be related to the development of hypertension.

Effect of erythropoietin therapy and withdrawal on blood coagulation and fibrinolysis in hemodialysis patients

Erythropoietin (EPO) therapy in hemodialysis patients may be associated with an enhanced risk of vascular access and extracorporeal thrombosis. Assessment of blood coagulation and fibrinolysis was performed monthly on a group of 21 hemodialysis patients treated with EPO, and on four iron-deficient hemodialysis patients treated with iron dextran infusions alone. Seventeen of the EPO treated patients were also monitored after withdrawal of EPO to allow hemoglobin to fall to pre-EPO levels, and 16 of these patients during a second subsequent phase of EPO therapy with EPO administered using the alternative route (subcutaneous/intravenous) from the first phase of treatment. Ten untreated hemodialysis patients with intrinsically high hemoglobins were studied as controls. EPO was associated with significant increases in the endothelial product Factor VIII von Willebrand factor antigen (FVIIIvWFAg), and plasma fibrinogen, to levels comparable to those observed in the untreated control patients. Both FVIIIvWFAg and fibrinogen remained significantly elevated when EPO was withdrawn. Whole blood platelet aggregation (spontaneous, collagen, and ADP-induced) also increased following EPO, collagen and ADP-induced aggregation, increasing further when EPO was withdrawn. Transient but significant changes occurred in plasma measures of thrombin-antithrombin III complex, prostacyclin stimulating factor, and protein C during the first EPO treatment phase, and also thrombin-antithrombin III complex during the second treatment phase, all favoring a tendency to thrombosis. D-dimer increased significantly following EPO withdrawal. Erythrocyte deformability, and granulocyte aggregation did not change. There was no effect of route of EPO administration (subcutaneous or intravenous) or EPO dose on any of these parameters.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of Erythropoietin Therapy on Diet and Dialysis Clearances in Hemodialysis Patients

Treatment of renal anemia with recombinant human erythropoietin in chronic hemodialysis patients has been reported to lead to increased appetite, and in several studies, to an increase in predialysis serum urea, potassium and creatinine values. We recorded dietary intake, and dialysis clearances for creatinine, urea and uric acid in a group of 12 anemic hemodialysis patients treated with recombinant erythropoietin (epoetin beta). A gradual increase was noted in dietary intake of calories, carbohydrate and sodium during the study period, attaining statistical significance after 10-12 months of therapy. A trend toward increased dietary intake of protein, lipid and potassium was observed, but the differences did not achieve statistical significance. Although a trend toward decreased dialysis clearance at higher hematocrits was found for creatinine clearances did not change significantly for any of the solutes examined, and linear regression analysis did not demonstrate a strong relationship between dialyzer clearance and hematocrit values within the range observed in this study.

Effect of Erythropoietin Therapy on the Red Cell Volume of Uraemic and Non‐uraemic Rats

Studies were performed to determine the effect of injecting repeated doses of erythropoietin (Ep) on the red cell volume of chronically uraemic rats and on that of non-uraemic sham operated ones. After 13 doses of Ep (5 u/dose), started either 5 or 21 d after removal of five-sixths of the renal mass, the increase in the red cell volume of uraemic rats was as great as that of non-uraemic ones. The significance of these results is discussed.

Effect of Erythropoietin Therapy on the Red Cell Volume of Uraemic and Non-uraemic Rats

Summary. Studies were performed to determine the effect of injecting repeated doses of erythropoietin (Ep) on the red cell volume of chronically uraemic rats and on that of non-uraemic sham operated ones. After 13 doses of Ep (5 u/dose), started either 5 or 21 d after removal of five-sixths of the renal mass, the increase in the red cell volume of uraemic rats was as great as that of non-uraemic ones. The significance of these results is discussed.