Effectiveness of erythropoiesis on supervised intradialytic oral iron and vitamin C therapy is correlated with Kt/V and patient weight

BACKGROUND: Poor compliance to oral medication and diet is common in hemodialysis (HD) patients and limits the ability of oral iron therapy to support erythropoiesis. Intravenous (i.v.) iron may be associated with undesirable and sometimes life-threatening complications. PATIENTS AND METHODS: We hypothesized that intradialytic oral iron therapy can overcome compliance problems and support effective maintenance erythropoiesis, which will keep Hct in the range of 33% to 36% and EPO requirements up to 50 units/week/kg. In a prospective observational study, SC EPO-treated hospital-based HD patients without conditions known to cause EPO resistance, were managed on intradialytic oral administration of iron and vitamin C. The primary endpoints were EPO requirements and resistance to EPO which standardized EPO requirements by the Hct level. Secondary endpoints included parameters that might affect the primary endpoints. Exclusion criteria were refusal to take oral medication, prestudy Hct < 27%, recent i.v. iron therapy or transfusions, bleeding, clinical conditions obligating Hct > 30% and known causes of EPO resistance. Twelve patients completed minimal follow-up period of 9 months. RESULTS: Mean Hct was 34.4% (range: 31.8% - 40.2%). EPO requirements were 61.7 +/- 28.2 units/kg and below 52.5 units/kg in 50% of patients. Patients were classified into equal groups according to resistance to EPO, which was positively correlated (r = 0.71 p < 0.01) with body weight and Kt/V (r = -0.38, p < 0.05). CONCLUSION: In conclusion, intradialytic oral iron therapy can support effective maintenance erythropoiesis in 50% of patients without known causes for EPO resistance. High response to EPO and low EPO requirement are correlated with lower body weight and possibly improved dialysis.     

Overcoming barriers that inhibit proper treatment of anemia

Intravenous (i.v.) iron and recombinant human erythropoietin (EPO), like all other medications, are associated with the risk of adverse events. Historically, the primary concern with iron therapy has been the possibility of iron overload, which exposes the individual to the effects associated with nontransferrin-bound iron. Experience with EPO use has demonstrated an association with hypertension and with the upregulation of a number of markers of inflammation. The impact of these potential adverse effects merits careful analysis, given that both i.v. iron and EPO are designed for long-term use in a patient population at high risk for infection and cardiovascular disease. However, the incidence of iron overload and the risks associated with nontransferrin-bound iron have dramatically been reduced since the introduction of EPO therapy, and no data exist that demonstrate a definitive association between i.v. iron and an increased risk of morbidity related to infection or cardiovascular disease. On the other hand, EPO use is associated with hypertension, endothelial dysfunction, and prothrombotic and inflammatory states in hemodialysis patients. Risks associated with hypertension can be minimized by using the lowest effective EPO dose, which may be achieved through the regular use of i.v. iron. Judicious use of both i.v. iron and EPO may optimize cardiovascular outcomes.     

Experience of iron saccharate supplementation in haemodialysis patients treated with erythropoietin

We assessed the efficacy of intravenous (i.v.) iron saccharate (VENOFER) vs oral iron supplementation in haemodialysis patients treated with low-dose erythropoietin (EPO). Twenty haemodialysis patients with serum ferritin >200 ng/mL and transferrin saturation >30% were assigned to one of the two groups. In Group 1, 10 were given i.v. iron saccharate (100 mg i.v. twice weekly) post dialysis. In Group 2, oral ferrous sulphate 200 mg was given thrice daily. In both groups, subcutaneous EPO 25 units/kg body weight (BW) was started simultaneously, twice weekly. After 3 months (study completion) the mean haemoglobin and haematocrit was significantly increased in Group 1 than in Group 2 (Hb 11.60±0.64 G/dL vs 10.5 G/dL±1.14 P <0.01). The final mean EPO dose was 25% lower in Group 1 than in Group 2 (3400±1356 U/week vs 4600±1356 U/week P =0.10) and the mean serum ferritin was higher in the i.v. iron group than the oral group (671 ng/mL±388 vs 367 ng/mL±238 P =NS). The same was also observed with transferrin saturation (44.6%±19.8 in Group 1 vs. 29%±11.0 in Group 2 P =NS). No adverse effects were seen during the study. In conclusion, we observed that regular use of i.v. iron had a significantly enhanced haemoglobin response, better maintained serum ferritin and lower EPO dosage requirement than the oral iron group.     

Experience of iron saccharate supplementation in haemodialysis patients treated with erythropoietin

SUMMARY: We assessed the efficacy of intravenous (i.v.) iron saccharate (VENOFER) vs oral iron supplementation in haemodialysis patients treated with low-dose erythropoietin (EPO). Twenty haemodialysis patients with serum ferritin >200 ng/mL and transferrin saturation >30% were assigned to one of the two groups. In Group 1, 10 were given i.v. iron saccharate (100 mg i.v. twice weekly) post dialysis. In Group 2, oral ferrous sulphate 200 mg was given thrice daily. In both groups, subcutaneous EPO 25 units/kg body weight (BW) was started simultaneously, twice weekly. After 3 months (study completion) the mean haemoglobin and haematocrit was significantly increased in Group 1 than in Group 2 (Hb 11.60 ± 0.64 G/ dL vs 10.5 G/dL ± 1.14 P <0.01). the final mean EPO dose was 25% lower in Group 1 than in Group 2 (3400 ± 1356 U/week vs 4600 ± 1356 U/week P =0.10) and the mean serum ferritin was higher in the i.v. iron group than the oral group (671 ng/mL ± 388 vs 367 ng/mL ± 238 P =NS). the same was also observed with transferrin saturation (44.6%± 19.8 in Group 1 vs. 29%± 11.0 in Group 2 P =NS). No adverse effects were seen during the study. In conclusion, we observed that regular use of i.v. iron had a significantly enhanced haemoglobin response, better maintained serum ferritin and lower EPO dosage requirement than the oral iron group.     

口服与静脉铁剂治疗肾性贫血的对比观察

目的观察口服与静脉铁剂在维持性血液透析患者肾性贫血治疗中的应用。方法选择48例合并肾性贫血的维持性血液透析患者为研究对象,随机分为2组,口服组22例,静脉组26例。2组血液透析方案和红细胞生成素用量相同,口服组口服多糖铁复合物300mg／d,静脉组采用静脉滴注低分子右旋糖酐铁100mg／周,观察时间为6个月。结果6个月后,静脉组总有效率高于口服组（P〈0．01）,血红蛋白和血细胞压积高于口服组（P〈0．05）,2组转铁蛋白饱和度、血清铁蛋白及C反应蛋白无显著差异（P〉0．05）,而整体费用支出无显著差异（P〉0．05）。结论对于肾性贫血患者的长期巩固治疗,静脉补铁较口服补铁效果更好,并发症少,且并不增加治疗费用。     

Controversies in iron management

BACKGROUND: Iron therapy is required in hemodialysis patients receiving erythropoietic stimulators in order to achieve the target hemoglobin in the most efficient way. While oral iron has been disappointing in this regard, parenteral iron has been widely used, despite a significant incidence of severe side effects when iron dextran is used. The recent availability of a more effective form of oral iron (heme-iron), and safer forms of parenteral iron (iron sucrose and iron gluconate) has made iron management in this population simpler. Many questions remain, however, about the use, efficacy, and safety of these compounds in hemodialysis patients. METHODS: Current literature was reviewed and combined with the authors' clinical experience to address a number of current questions regarding the use of iron in hemodialysis patients. RESULTS: Although oral non-heme iron is infrequently sufficient to maintain iron stores in hemodialysis patients, recent studies suggest that heme-iron may be more useful in this regard. Heme-iron is absorbed to a greater extent than non-heme iron, and is better tolerated. Small studies have shown that when heme-iron is administered, less parenteral iron and lower doses of erythropoietin (EPO) are needed to maintain target hemoglobin. Current evidence suggests that both iron sucrose and iron gluconate are safer than iron dextran, and the latter should only be used in extraordinary circumstances. While in vitro studies have demonstrated some differences in the effects of iron sucrose and iron gluconate on cellular toxicity, the clinical importance of these has not been determined. Both compounds can be used safely for repletion and maintenance therapy, and doses of up to 300 mg of either are generally well tolerated when such higher doses are needed, as in peritoneal dialysis (PD) patients or chronic kidney disease (CKD) patients not on dialysis. CONCLUSION: A number of questions remain regarding the appropriate use, efficacy, and potential toxicity of iron therapy in dialysis patients. Further prospective research should address the myriad questions raised in this review.     

Maintenance intravenous iron therapy in pediatric hemodialysis patients

Iron supplementation is required for optimal response to erythropoietin (EPO) in hemodialysis patients. This is due to blood lost in the dialysis tubing after dialysis and the increased demand for iron by EPO therapy. Maintenance intravenous (IV) iron was administered according to a standardized protocol to pediatric patients on hemodialysis in our institution. The effect of this protocol on EPO dose, iron indices, anemia, and medication costs was evaluated. Data on two groups of patients were retrieved from the health records. Group 1 (n=14) consisted of patients treated in the 18 months prior to the protocol. These patients received oral iron supplements and occasional IV iron. Group 2 (n=5) consisted of all patients treated with the IV iron protocol. There was no difference in clinical characteristics and mean values for monthly hemoglobin, serum iron, ferritin, and transferrin saturation between groups. The dose of EPO was significantly reduced in group 2 compared with group 1 (193.9±121.4 vs. 73.9±39.0 units/kg per week, P<0.05). Medication costs were reduced by 26% in group 2. No significant adverse events were seen. Maintenance IV iron reduced the dose of EPO required to maintain blood hemoglobin levels. Our results also suggest that maintenance IV iron is a more-economic method of iron supplementation for pediatric hemodialysis patients. Received: 13 November 2000 / Revised: 23 April 2001 / Accepted: 24 April 2001     

Recombinant human erythropoietin independence in chronic hemodialysis patients: clinical features, iron homeostasis and erythropoiesis

AIMS: Recombinant human erythropoietin (r-HuEPO) is widely used to correct renal anemia in uremic patients. Interestingly, some chronic hemodialysis (HD) patients can maintain high hemoglobin level without the need of r-HuEPO. The aim of this study is to investigate clinical features, iron metabolism and erythropoiesis of these r-HuEPO-independent HD patients. METHODS: r-HuEPO independence was defined in dialysis patients as hemoglobin greater than 12 g/dl and no use of r-HuEPO for at least 6 months. An age- and sex-matched group was selected for comparison. Their underlying diseases, duration of hemodialysis therapy, efficacy of dialysis (Kt/V), normalized protein catabolic rate (nPCR) and body mass index (BMI) were recorded. Laboratory data including: hemoglobin, albumin, high sensitivity C-reactive protein, serum iron, total iron binding capacity, transferrin saturation, ferritin, intact parathyroid hormone, soluble transferrin receptor (sTfR), serum EPO, cortisol, testosterone, aluminum and leptin levels were measured. Renal sonography was also performed in each patient to evaluate renal cyst formation. RESULTS: About 2.3% of all HD patients (21/888; M : F = 18 : 3) were r-HuEPO-independent. These patients had significantly longer HD duration and higher serum EPO and sTfR levels, and lower transferrin saturation rate than dependent groups. Correlation analysis revealed that hemoglobin level strongly correlated with HD duration, serum sTfR and EPO levels. Levels of sTfR were positively related with serum EPO levels and BMI. Multivariate regression analysis showed that level of sTfR was the only independent factor related to r-HuEPO independence. CONCLUSION: R-HuEPO independence is rare among chronic hemodialysis patients. Factors contributing to this dependence are complex and multiple. Level of serum sTfR parallels erythropoiesis and is the most significant factor associated with r-HuEPO independence in chronic HD patients.     

Lower erythropoietin and iron supplementation are required in hemodialysis patients with hepatitis C virus infection

BACKGROUND: Chronic hepatitis C virus (HCV) infection is a common infectious agent in chronic hemodialysis (HD) patients. In this prospective case-control study, we aimed to investigate the influence of chronic HCV infection on erythropoietin (EPO) and iron requirement in HD patients. PATIENTS AND METHODS: 49 HD patients (24 male, 25 female, mean age 47 +/- 15 years) were included. The mean time spent on dialysis was 39 +/- 38 months, and follow-up time was 1 year for this study. Biochemical analyses and complete blood counts together with iron status of the patients (transferrin saturation and serum ferritin levels) were measured monthly. Highly sensitive C-reactive protein (hs-CRP) levels were measured within 3-month intervals. Endogenous EPO levels were measured by enzyme-linked immunoassay 2 weeks after cessation of EPO treatment. RESULTS: Eleven of the HD patients (22%) were anti-HCV(+). There was no difference in age, sex, time on dialysis, distribution of primary renal diseases, predialytic BUN, Kt/V, albumin and i-PTH levels between HCV(+) and (-) patients. Anti-HCV-positive patients required significantly lower weekly doses of EPO (87 +/- 25 IU/kg vs 129 +/- 11 IU/kg, p = 0.042) and iron (16.8 +/- 12.2 mg vs 32.6 +/- 16.1 mg, p = 0.02) replacement than anti-HCV(-) group; hs-CRP levels were similar between study groups. Serum endogenous EPO levels were significantly higher in HCV(+) patients than HCV(-) HD patients (9.43 +/- 6.47 mU/ml vs 3.59 +/- 2.08 mU/ml, p = 0.008). CONCLUSION: Anti-HCV(+) HD patients had higher serum EPO levels and required less EPO and iron replacement as compared to anti-HCV(-) patients. Because of the changes in iron metabolism, iron treatment should be carefully administered in HD patients with HCV.     

Soluble transferrin receptor is correlated with erythropoietin sensitivity in dialysis patients.

BACKGROUND: Iron deficiency is the most common cause of erythropoietin (EPO) resistance in dialyzed patients with renal anemia. Subclinical or functional iron deficiency is difficult to diagnose in these patients. The soluble transferrin receptor (sTf-R) is considered as a sensitive and specific indicator of bone marrow iron availability. PATIENTS AND METHODS: To evaluate the clinical usefulness of this novel marker, we investigated relationships between EPO requirements and various hematological and biochemical parameters of erythropoiesis in 27 pediatric end-stage renal failure patients treated by hemodialysis (HD, n = 11) or chronic peritoneal dialysis (PD, n = 16). Iron was substituted intravenously once or twice per week in HD, and by daily oral administration to PD patients. Serum sTf-R concentrations were measured by an enzyme-linked immunosorbent assay. Serum ferritin and transferrin concentrations were determined using nephelometric assays. Hemoglobin and iron levels were estimated by automated procedures. RESULTS: While neither transferrin saturation nor serum ferritin concentrations were indicative of EPO requirements, a highly significant correlation between the EPO efficacy index (EPO dose divided by hemoglobin concentration) and sTf-R was observed (r = 0.65, p = 0.001). The intravenous iron substitution in HD patients was associated with higher ferritin concentrations compared to the orally substituted PD patients (280+/-100 ng/ml vs. 124+/-83 ng/ml, p<0.002). In contrast, sTf-R concentrations were similar in both treatment groups (25.7+/-7.7 nM vs. 27+/-10.8 nM, n.s.), as were hemoglobin concentrations and EPO requirements. CONCLUSION: Our results suggest that sTf-R is a more sensitive indicator of functional iron deficiency and impaired EPO responsiveness than serum ferritin or transferrin saturation in dialyzed patients. Intensified iron substitution to patients with elevated sTf-R concentrations may considerably improve the cost efficacy of EPO treatment.     

静脉注射和口服铁剂治疗肾性贫血的成本效果分析

目的 比较静脉注射铁剂和口服铁剂治疗肾性贫血的成本效果。 方法 对入选的235 例肾性贫血患者进行随机分组，分别采用静脉注射铁剂和口服铁剂治疗。静脉组根据预计补铁量，于透析过程中进行右旋糖酐氢氧化铁静脉滴注，完成总量后，根据患者铁蛋白和血红蛋白水平，定期给予100 mg维持量。口服组每天口服相当于200 mg铁的琥珀酸亚铁，连续服用。226例完成26周临床观察，静脉组和口服组各113例。以铁剂治疗前后患者血红蛋白和红细胞比容的变化及治疗的好转程度衡量治疗效果，以有效率作为效果指标。治疗成本包括铁剂、红细胞生成素(EPO)、化验检查和不良反应治疗等直接医疗成本，患者的交通、陪护和辅助营养保健品等直接非医疗成本以及患者劳动力损失的间接成本。 结果 26周的研究结果表明，静脉组与口服组人均总治疗费用分别为2.49万 元和2.41万元，差异无统计学意义(P >0.05)；静脉组和口服组治疗总有效率分别为88.5 %和71.68%，差异有统计学意义(P < 0.05)。经成本效果分析，口服组26 周有效治疗1例患者花费3.37万元；静脉组26 周有效治疗1例患者花费2.82万元。 结论 静脉组与口服组比较治疗成本没有差别，疗效更好，静脉组治疗肾性贫血更具成本效果，值得临床推荐。     

The effect of i.v. iron alone or in combination with low-dose erythropoietin in the rapid correction of anemia of chronic renal failure in the predialysis period

BACKGROUND: It is now more and more evident that anemia of predialysis chronic renal failure (CRF) should be actively treated, since long-standing anemia may cause irremediable damage to the heart. The most common form of treatment of this anemia is subcutaneous erythropoietin (EPO). iron (Fe) deficiency can also contribute to anemia in predialysis CRF, and intravenous iron (i.v. Fe) can frequently improve it. It is possible, therefore, that the combination of EPO and i.v. Fe may have an additive effect, and cause a rapid improvement in anemia with relatively small doses of EPO. PURPOSE: The purpose of this study was an initial study: to assess the ability of a combination of low-dose EPO and i.v. Fe, given weekly for 5 doses, to correct the anemia of predialysis CRF patients compared to the use of i.v. Fe alone in a randomized study. In the follow-up study: to assess the ability of the maintenance of adequate iron stores for one year to achieve and maintain the target Hct of 35% with the minimum dose of EPO. Initial study: METHOD: Ninety predialysis CRF patients (creatinine clearance 10-40 ml/min/1.73 m2 received either: Group A (45 patients): 200 mg i.v. Fe as Fe sucrose (Venofer, Vifor Int.) once per week for 5 doses in combination with 2,000 international units (IU) EPO (Eprex, Cilag-Janssen), subcutaneously given simultaneously also for 5 doses. Group B (45 patients): the same dose of i.v. Fe as in Group A but without EPO. RESULTS: The mean increase in hematocrit (Hct) and hemoglobin (Hb) by one week after the last dose was greater in group A, 4.54 +/- 2.64% (p < 0.01) and 1.37 +/- 0.84 g% (p < 0.01), respectively, than in Group B, 2.74 +/- 2.72% (p < 0.05) and 0.91 +/- 0.78 g% (p < 0.05), respectively. 80% of those in Group A had an increase in Hct of 3 vol% or more compared to 48.9% in Group B (p < 0.01). 40% of those in Group A reached the target Hct of 35% compared to 28.9% in Group B (p > 0.05). Follow-up study: During a 12-month follow-up period, enough i.v. iron was given to maintain the Hct at 35%, while keeping the serum ferritin at < 400 ug/l and % Fe Sat at < 40%. If the i.v. Fe alone was not capable of maintaining the target Hct, EPO was given in increasing doses. Eighteen patients required dialysis. Of the 72 patients who did not require dialysis, 24 (33.3%) maintained the target Hct with i.v. Fe alone, without EPO. All the remaining 48 patients (66.7%) continued to receive EPO in addition to the i.v. Fe, and 47 achieved and maintained the target Hct with a mean EPO dose of 2,979 +/- 1,326 IU/week. CONCLUSION: The combination of low-dose EPO and i.v. Fe had a rapid and additive effect on the correction of anemia in CRF predialysis patients. Maintaining adequate iron stores with i.v. Fe during a subsequent maintenance phase allowed the target Hct of 35% to be reached and maintained with low-dose EPO in two-thirds of the predialysis patients and with no EPO at all in one-third.     

Iron deficiency is a common cause of anemia in chronic kidney disease and can often be corrected with intravenous iron

BACKGROUND: There is some epidemiological and clinical evidence that the anemia seen in chronic kidney disease (CKD) in patients not on dialysis could be due to a significant extent to iron deficiency, and that adequate iron replacement could cause a marked improvement in the anemia even without the use of erythropoietin (EPO). The purpose of this work was to study the effects of intravenous (i.v.) iron administration (ferric gluconate - Ferrlecit) on hemoglobin (Hb) of patients with CKD. METHODS: Forty-seven consecutive patients with CKD with Hb <12 g/dL in whom no underlying cause for the anemia could be found underwent sternal bone marrow biopsy and had their red cell and blood iron parameters measured. They then received 250 mg of ferric gluconate (Ferrlecit) intravenously twice monthly for 3 months, and had their blood parameters measured 1 month later. No patient received erythropoietin (EPO). RESULTS: Forty-six patients had no evidence of any iron deposits in the bone marrow - consistent with the presence of severe iron deficiency. The mean serum ferritin and %transferrin saturation prior to treatment were 235.9 +/- 54.3 ug/L and 13.5 +/- 4.1%, respectively, and both increased significantly with the iron treatment. Mean Hb increased from 10.16 +/- 1.32 to 11.96 +/- 1.52 g/dL, an increase of 1.80 +/- 1.72 g/dL (p<0.01). Twenty-six patients (55.3%) reached the target Hb of 12 g/dL. Ten patients (21.3%) had an increase of 0.1-0.9 g/dL, nine patients (19.1%) had an increase of 1-1.9 g/dL and 23 patients (48.9%) had an increase of >or= 2 g/dL. CONCLUSIONS: Iron deficiency is frequently seen in anemic CKD patients not on dialysis and its correction with i.v. iron will often cause a marked increase in the Hb level, and the achievement of the target Hb of 12 g/dL even without EPO.     

Selection of hemodialysis versus cadaveric transplantation.

The records of 272 recipients of cadaver allografts and of 650 dialyzed patients (440 center dialysis and 210 home dialysis) were reviewed in an attempt to determine whether hemodialysis or transplantation is the best treatment for end-stage renal failure. Home dialysis patient survival is slightly better than that of cadaver kidney recipients and far better than center dialysis patient survival. When considering the quality of life assumed by the degree of social and professional rehabilitation, cadaver kidney transplantation appears the optimal choice. Finally, the life expectancy of a patient is higher if he embarks upon an integrated program where hemodialysis is a complementary adjunct to cadaver kidney transplantation.     

Erythropoietin treatment in children with renal failure

 Erythropoietin (EPO) treatment dramatically changes the life of a child with end-stage renal disease. The administration of recombinant human (rHu)EPO is beneficial and safe in the predialysis period, during hemodialysis or peritoneal dialysis, and after renal transplantation. The goal of hemoglobin correction should be the level at which normal quality of life is possible without adverse events: in children this is usually 10–11 g/dl. rHuEPO is administered once to twice a week subcutaneously to children before dialysis, during peritoneal dialysis, and after transplantation. There is no real benefit of intraperitoneal administration. In children on hemodialysis two to three times a week IV administration is preferred. Among the many reasons for non-response to rHuEPO, iron deficiency (absolute or functional), infections, and hyperparathyroidism are the most common in the pediatric renal patient. Hypertension is the most-frequent side effect of rHuEPO treatment and needs careful monitoring. Iron should be supplemented orally or IV. No significant beneficial effect of rHuEPO on growth has been demonstrated. However, the association with recombinant human growth hormone therapy is not detrimental in children. Received: 4 May 1998 / Revised: 31 July 1998 / Accepted: 31 July 1998     

Dialysis adequacy in patients with acute renal failure

Measurement of dialysis adequacy in patients with end-stage renal disease involves the use of urea kinetic modeling, which is a reflection of both dietary protein intake and efficiency of small solute clearance. Different dialytic modalities are available for patients in acute renal failure, including intermittent hemodialysis, continuous renal replacement therapies and peritoneal dialysis. In recent years, there has been a growing effort to measure dialysis adequacy in patients with acute renal failure using urea kinetic modeling. This initiative has been driven by the persistently high mortality rates in patients with dialysis-requiring acute renal failure, which may partly be related to inadequate dialysis dosing. In the setting of acute renal failure, dialysis adequacy has been measured using both single-pool and double-pool urea kinetics, as well as blood-based and dialysate-based urea kinetic modeling. Unfortunately, current goals and methods of measuring dialysis adequacy have been extrapolated from the end-stage renal disease patient population. These extrapolations are problematic because of differences in total body water, protein catabolic rate, and vascular access. Continuous renal replacement therapy has theoretical advantages over intermittent hemodialysis, including a decreased tendency to induce hypotension, and improved solute clearance and fluid removal, while allowing intensive nutritional support, and a better clearance of medium- to large-size molecules. The latter may play a significant role in patients with sepsis-associated acute renal failure. To date, comparative studies are scant and equivocal in establishing the superiority of a particular dialysis dose or modality.     

Cost-effectiveness analysis of treatment with epoietin-alpha for patients with anaemia due to renal failure: the case of Sweden

OBJECTIVE: Anaemia is a common complication of renal failure. It can be treated with erythropoietin (EPO) administration, red blood cell transfusion (RBCT), or a combination of both. EPO has been registered for the treatment of renal anaemia in Sweden since the beginning of the 1990s, and is the primary treatment regimen for anaemia related to renal failure. The objective of this study was to carry out a cost-effectiveness analysis from a provider perspective of a treatment strategy comprising EPO and complementary RBCT compared to the traditional treatment of RBCT alone for patients with anaemia associated with renal failure in Sweden. MATERIAL AND METHODS: Incremental costs and quality-adjusted life-years (QALYs) associated with EPO (epoietin-alpha) treatment compared to the traditional therapy of RBCT were estimated. The QALY gains were estimated using a modified version of a Markov model, which is used by the UK National Institute of Clinical Excellence in their evaluations of EPO treatment in the UK. Swedish treatment practice (i.e. EPO doses and iron supplementation), patient characteristics and unit costs were used throughout the study. RESULTS: The estimated cost per QALY gained from administration of EPO to renal patients falls within the range acceptable in Sweden for both haemodialysis and peritoneal dialysis patients. CONCLUSIONS: EPO administration to renal patients is much more costly in Sweden than in the UK, primarily due to the higher dosage of EPO and iron supplementation used in Sweden. However, Swedish patients reach higher haemoglobin levels, and thereby achieve higher QALY gains, compared to patients in the UK.     

Possible role of soluble erythropoietin receptors in renal anemia

Recombinant human erythropoietin(rHuEpo) is effective for the treatment of renal anemia associated with chronic renal failure(CRF). However, we have encountered some patients with CRF who have sometimes developed a resistance to rHuEpo. This resistance can be due to iron or folate deficiency, aluminum toxicity, hyperparathyroidism, or auto-antibodies for rHuEpo. In this study, we focused on the soluble erythropoietin receptor(sEpoR), which can bind to rHuEpo. To demonstrate the possibility that the sweeping of rHuEpo by sEpoR results in resistance to rHuEpo, we performed a bioassay using the rHuEpo-dependent cell line, UT7/EPO. The results showed that recombinant mouse sEpoR(rmsEpoR) can reduce the proliferation of UT7/EPO induced by rHuEpo in a dose-dependent manner. We consider that this cell line could be a useful tool in a bioassay to detect the inhibitory factor(s) against Epo. We selected sera from three groups of patients with renal anemia associated with CRF who were receiving hemodialysis three times a week: the first was a patient group that needed a high dose of rHuEpo(7,500-9,000 unit/dialysis), the second was a patient group that needed an intermediate dose of rHuEpo (4,500 unit/dialysis), the third was a patient group that needed a low dose of rHuEpo(below 1,500 unit/dialysis). Interestingly, the proliferation of UT7/EPO determined with [3H]-thymidine incorporation was reduced by the addition of sera from the first group, but not by the addition of sera from the third group. These results suggested that serum sEpoR may play an important role in signal transduction via EpoR on erythroid progenitor in CRF patients.     

Effect of an intravenous iron dextran regimen on iron stores, hemoglobin, and erythropoietin requirements in hemodialysis patients

Iron deficiency is a common cause of delayed or diminished response to erythropoietin (EPO) in hemodialysis patients. Although oral iron is often prescribed to replete iron stores, this approach to iron supplementation may not be adequate with chronic EPO therapy. Intravenous (IV) iron dextran may be an effective alternative approach to replete iron stores and may facilitate more cost-effective use of EPO. The purpose of this study was to evaluate an IV iron dextran regimen that consisted of a loading dose phase followed by monthly maintenance doses of iron dextran. The effect of this regimen on iron stores, hemoglobin, and EPO doses was evaluated. This was an open prospective study in adult hemodialysis patients who were iron deficient as defined by a serum ferritin less than 100 ng/mL or transferrin saturation (TSAT) of less than 20%. Patients were loaded with 1 g iron dextran in five divided doses and then received monthly maintenance doses of 100 mg for the 4-month study period. Values of serum ferritin, TSAT, hemoglobin, and EPO dose were followed for the 4-month study period. Thirty hemodialysis patients receiving EPO were identified as being iron deficient and were enrolled in the study. The mean serum ferritin increased significantly from 49 ng/mL at baseline to 225 ng/mL at the end of the study period (P < 0.0001). Mean TSAT also increased significantly from 27% to 33% (P = 0.002). Values for hemoglobin did not change significantly during the study period; however, there was a significant reduction in EPO dose from a mean baseline dose of 112 U/kg/wk to 88 U/kg/wk at the end of the study period (P = 0.009). Seventeen patients experienced an increase in hemoglobin or a decrease in EPO dose. Economic analysis showed that approximately $580 (Cdn) per patient per year could be saved by use of IV iron dextran. The administration of the IV iron dextran regimen in the iron-deficient hemodialysis population was effective at repleting and maintaining iron stores and reducing EPO use.     

Clinical relevance of hemochromatosis-related HFE C282Y/H63D gene mutations in patients on chronic dialysis

BACKGROUND: The actual prevalence and the clinical relevance of gene mutations of HFE (which are linked to hemochromatosis) have not yet been established in patients on chronic dialysis. On the basis of theoretical premises, it could be hypothesized that these genetic determinants might influence the response to iron intake and the susceptibility for iron overload in patients in parenteral iron therapy. Furthermore, carriers for these mutations might be prone to develop sporadic porphyria cutanea tarda and cardiovascular events. METHODS: C282Y/H63D mutations of HFE gene were evaluated in 132 patients (34 in peritoneal dialysis, 98 in HD) and correlated with biochemical parameters of iron status (ferritin (FER) concentration and transferrin saturation (TSAT)), red cell parameters (red cell size and hemoglobin content), erythropoietin (EPO) dosage, major cardiovascular events and C-reactive protein as marker of chronic inflammation, in patients without iron therapy and after i.v. iron supplementation (< or = 60 mg/week) and with the presence of biopsy-proven porphyria. RESULTS: C282Y heterozygous mutation was found in 8/132 (6.6%); H63D homozygous and heterozygous mutations were found in 3/132 (2.3%) and 22/132 (16%) patients, respectively. Two patients (1.5%) showed double heterozygosis. No differences in baseline serum FER and TSAT and the other biochemical and clinical parameters were found in patients bearing mutations alleles nor after continuous iron therapy at low dosages. However, the prevalence of patients capable of maintaining normal hemoglobin (Hb) level without EPO therapy is increased in the C282Y-mutated patients. Only 1 patient out of the 4 with biopsy-proven porphyria cutanea tarda was bearing gene mutations (H63D heterozygosis). CONCLUSION: C282Y/H63D HFE gene mutations do not seem to be related to major abnormalities in biochemical parameters of iron status in dialysis patients without iron therapy or after i.v. iron supplementation, granted that low dosages are employed. Obviously, as our patients were exposed to a relatively uniform iron regimen in our clinical center (< or = 60 mg/week), it is unclear if other dosing regimens will unmask clinically significant differences between the heterozygotes and normals. The fact that the C282Y-mutated patients more frequently maintain high Hb values without EPO is interesting as could suggest a better use of available iron for erythopoiesis, but needs to be confirmed in larger samples. No clear association is demonstrated with porphyria cutanea tarda and major cardiovascular events.