The new FDA label for erythropoietin treatment: how does it affect hemoglobin target?

Red blood cell alloimmunisation in multi-transfused patients with chronic renal failure undergoing haemodialysis in Ouagadougou, Burkina Faso, 2018

Background

In Burkina Faso, red blood cell (RBC) transfusion remains the crucial anaemia treatment following chronic renal failure (CRF) as erythropoietin and its analogues are unavailable. However, blood group matching beyond the ABO and Rhesus is not common in Burkina Faso. Thus, alloimmunisation is a potential issue for transfused patients.

Objective

Our study aimed to identify anti-erythrocyte antibodies in multi-transfused CRF patients at the Yalgado Ouedraogo Teaching Hospital, Ouagadougou, Burkina Faso.

Methods

This cross-sectional study, conducted from October 2018 to November 2019, included CRF patients who had received at least two RBC units. We screened patients for the presence of RBC antibodies using three commercial Cells panels and identified antibody specificities for positive screenings using 11 Cells panels for an indirect antiglobulin test (IAT) in a low ionic strength microcolumn gel-card system.

Results

Two hundred and thirty-five patients (45.1% female; average age: 41.5 years) were included. The median number of blood units received per patient was 10 (interquartile range: 5–20). The overall alloimmunisation rate was 5.9% (14/235). Antibodies identified included: anti-D (1 case), anti-C (1 case), anti-D+C (4 cases), anti-C^W (1 case), anti-E (1 case), anti-S (1 case) and anti-Le^a (1 case). In four positive patients, the specificity of the antibodies was indeterminate. No risk factors were associated with alloimmunisation.

Conclusion

In Burkina Faso, screening for RBC alloantibodies should be mandated for patients at risk. The high rate of indeterminate antibodies suggests the need to develop a local RBC antibody panel adapted to the local population.

Medicare Bundled Payment Policy on Anemia Care, Major Adverse Cardiovascular Events, and Mortality among Adults Undergoing Hemodialysis

BACKGROUND AND OBJECTIVES

In 2011, the Centers for Medicare & Medicaid Services implemented bundling of all services for patients receiving dialysis, including erythropoietin-stimulating agents use, and the Food and Drug Administration recommended conservative erythropoietin-stimulating agent dosing.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This retrospective cohort study investigated anemia care and clinical outcomes before and after the Centers for Medicare & Medicaid Services bundled payment and the revised Food and Drug Administration-recommended erythropoietin-stimulating agent labeling for Medicare-insured adults receiving hemodialysis using data from the United States Renal Data System from January 1, 2006 to December 31, 2016. Clinical outcomes included major adverse cardiovascular event (stroke, acute myocardial infarction, and all-cause mortality), cardiovascular mortality, and heart failure. Measurements were compared between prepolicy (2006-2010) and postpolicy (2012-2016) implementation using interrupted time series and Cox proportional hazards regression models.

RESULTS

Of 481,564 patients, erythropoietin-stimulating agent use immediately decreased by 84.8 per 1000 persons (P<0.001), with a significant decrease in the slope of the trend line (both P=0.001). Blood transfusion use rapidly increased by 8.34 per 1000 persons in April 2012 and then gradually decreased (both P=0.001). The percentage of patients with hemoglobin >11 g/dl decreased from 68% in January 2006 to 28% in December 2016, whereas those with hemoglobin <9 g/dl increased from 5% to 9%. Overall major adverse cardiovascular event (adjusted hazard ratio, 0.95; 95% confidence interval, 0.94 to 0.96), stroke (adjusted hazard ratio, 0.83; 95% confidence interval, 0.80 to 0.86), all-cause mortality (adjusted hazard ratio, 0.87; 95% confidence interval, 0.86 to 0.89), cardiovascular mortality (adjusted hazard ratio, 0.81; 95% confidence interval, 0.79 to 0.83), and heart failure (adjusted hazard ratio, 0.86; 95% confidence interval, 0.84 to 0.88) risks were lower. Acute myocardial infarction risk (adjusted hazard ratio, 1.04; 95% confidence interval, 1.01 to 1.06) was higher after policies changed.

CONCLUSIONS

The Medicare reimbursement policy and Food and Drug Administration-recommended erythropoietin-stimulating agent dosing changes were associated with lower erythropoietin-stimulating agent use and lower hemoglobin levels. These changes in anemia care were associated with lower risks of major adverse cardiovascular event, stroke, mortality, and heart failure but higher risk of acute myocardial infarction among adults receiving hemodialysis.

The anaemia control model: Does it help nephrologists in therapeutic decision-making in the management of anaemia?

INTRODUCTION

Anaemia is common in haemodialysis patients and treating it with erythropoiesis-stimulating agents (ESAs) is complex due to many factors.

OBJECTIVES

To assess the usefulness of the Anaemia Control Model (ACM) in the treatment of anaemia in haemodialysis.

METHODS

ACM is a software that predicts the optimal dose of darbepoetin and iron sucrose to achieve target haemoglobin (Hb) and ferritin levels, and makes prescription suggestions. Study conducted in dialysis clinics lasting 18months with two intervention phases (IPs) with ACM (IP1, n:213; IP2, n:218) separated by a control phase (CP, n:219). The primary outcome was the percentage of Hb in range and the median dose of ESAs, and the secondary outcomes were transfusion, hospitalisation and cardiovascular events. Clinical and patient analyses were performed. Hb variability was assessed by the standard deviation (SD) of the Hb. We also analysed the patients with most of the suggestions confirmed (ACM compliant group).

RESULTS

ACM increased the percentage of Hb in range: 80.9% in IP2, compared with 72.7% in the CP and reduced the intake of darbepoetin (IP1: 20 [70]; CP 30 [80] μg P=0.032) with less Hb fluctuation (0.91±0.49 in the CP to 0.82±0.37g/dl in IP2, P<0.05), improving in the ACM compliant group. The secondary outcomes decreased with the use of ACM.

CONCLUSIONS

ACM helps to obtain better anaemia results in haemodialysis patients, minimising the risks of treatment with ESAs and reducing costs.

Oxygen sensors as therapeutic targets in kidney disease

Hypoxia is a common clinical problem that has profound effects on renal homeostasis. Prolyl-4-hydroxylases PHD1, 2 and 3 function as oxygen sensors and control the activity of hypoxia-inducible factor (HIF), an oxygen-sensitive transcription factor that regulates a multitude of hypoxia responses, which help cells and tissues to adapt to low oxygen environments. This review provides an overview of the molecular mechanisms that govern these hypoxia responses and discusses clinical experience with compounds that inhibit prolyl-4-hydroxylases to harness HIF responses for therapy in nephrology.

Home Dialysis in the Prospective Payment System Era

The ESRD Prospective Payment System introduced two incentives to increase home dialysis use: bundling injectable medications into a single payment for treatment and paying for home dialysis training. We evaluated the effects of the ESRD Prospective Payment System on home dialysis use by patients starting dialysis in the United States from January 1, 2006 to August 31, 2013. We analyzed data on dialysis modality, insurance type, and comorbidities from the United States Renal Data System. We estimated the effect of the policy on home dialysis use with multivariable logistic regression and compared the effect on Medicare Parts A/B beneficiaries with the effect on patients with other types of insurance. The ESRD Prospective Payment System associated with a 5.0% (95% confidence interval [95% CI], 4.0% to 6.0%) increase in home dialysis use by the end of the study period. Home dialysis use increased by 5.8% (95% CI, 4.3% to 6.9%) among Medicare beneficiaries and 4.1% (95% CI, 2.3% to 5.4%) among patients covered by other forms of health insurance. The difference between these groups was not statistically significant (1.8%; 95% CI, -0.2% to 3.8%). Conversely, in both populations, the training add-on did not associate with increases in home dialysis use beyond the effect of the policy. The ESRD Prospective Payment System bundling, but not the training add-on, associated with substantial increases in home dialysis, which were identical for both Medicare and non-Medicare patients. These spill-over effects suggest that major payment changes in Medicare can affect all patients with ESRD.

Effect of normovolemic hematocrit changes on blood pressure and flow

AIMS

In patients with chronic kidney disease (CKD), severe anemia is associated with increased cardiovascular risk. Although elevating hemoglobin (Hb) and hematocrit (Hct) levels with erythropoiesis-stimulating agents (ESA) improves patients' quality of life, normalization of Hb does not reduce cardiovascular risk and the reason remains unclear.

MAIN METHODS

We measured the effect of acute isovolumic changes in Hct from 37±5 to 50±2% (mean±SD) on arterial blood pressure (BP), cardiac output (CO), and carotid and renal blood flow (BF), (1) in control rats and (2) after acute blockade of the nitric oxide (NO) pathway by l-NAME.

KEY FINDINGS

1) In control conditions, BP, CO and carotid and renal BF remained stable for Hct values between 38±2 and 46±1%; 2) for higher Hct values, BP rose together with increasing blood viscosity whereas CO and renal BF decreased; 3) during acute NO blockade, CO, and carotid and renal BF were significantly reduced and remained low whereas BP increased with Hct thus increasing blood viscosity. Our results suggest (1) the ceiling level of endothelium-mediated vasodilation for high values of blood viscosity under control conditions, and (2) the need for efficient endothelial function for vasomotor adaptation of hemodynamic resistances to blood viscosity.

SIGNIFICANCE

(1) Clinical benefits of ESA in CKD patients with severe endothelial dysfunction are primarily due to increased oxygen transport and supply and, (2) normalization of Hct values in these patients may prove deleterious because of significant increases in BP and reductions in BF associated with high blood viscosity.

Distinct subpopulations of FOXD1 stroma-derived cells regulate renal erythropoietin

Renal peritubular interstitial fibroblast-like cells are critical for adult erythropoiesis, as they are the main source of erythropoietin (EPO). Hypoxia-inducible factor 2 (HIF-2) controls EPO synthesis in the kidney and liver and is regulated by prolyl-4-hydroxylase domain (PHD) dioxygenases PHD1, PHD2, and PHD3, which function as cellular oxygen sensors. Renal interstitial cells with EPO-producing capacity are poorly characterized, and the role of the PHD/HIF-2 axis in renal EPO-producing cell (REPC) plasticity is unclear. Here we targeted the PHD/HIF-2/EPO axis in FOXD1 stroma-derived renal interstitial cells and examined the role of individual PHDs in REPC pool size regulation and renal EPO output. Renal interstitial cells with EPO-producing capacity were entirely derived from FOXD1-expressing stroma, and Phd2 inactivation alone induced renal Epo in a limited number of renal interstitial cells. EPO induction was submaximal, as hypoxia or pharmacologic PHD inhibition further increased the REPC fraction among Phd2-/- renal interstitial cells. Moreover, Phd1 and Phd3 were differentially expressed in renal interstitium, and heterozygous deficiency for Phd1 and Phd3 increased REPC numbers in Phd2-/- mice. We propose that FOXD1 lineage renal interstitial cells consist of distinct subpopulations that differ in their responsiveness to Phd2 inactivation and thus regulation of HIF-2 activity and EPO production under hypoxia or conditions of pharmacologic or genetic PHD inactivation.

Acetylsalicylic acid mitigates erythropoietin-associated blood pressure increase in nonuremic rats

BACKGROUND

Approximately 30% of the chronic kidney disease patients using recombinant human erythropoietin (rhuEPO) have an increase in blood pressure (BP). Its mechanism and whether it depends on renal function remain unclear. There is early evidence that acetylsalicylic acid (ASA) prevents the rhuEPO-induced increase in BP. This study aims to verify whether very high doses of rhuEPO can increase BP in nonuremic rats and whether the co-administration of ASA can prevent it.

METHODS

Forty male Wistar rats were divided into four groups: placebo/placebo; placebo/rhuEPO 200 UI/kg thrice weekly; placebo/ASA 50 mg/kg daily; rhuEPO 200 UI/kg thrice weekly/ASA 50 mg/kg daily. Hematocrit was measured before and after and systolic BP was measured weekly by tail-cuff technique. Direct measurement of the BP was obtained at the end.

RESULTS

The rhuEPO groups had higher final hematocrit (rhuEPO/placebo 56.7 ± 7.6, rhuEPO/ASA 56.7 ± 7.7; p < 0.001 versus placebo/placebo, 42.2 ± 4.7 and ASA/placebo 41.2 ± 4.2); and also increase in systolic BP (rhuEPO/placebo 135.1 ± 15.0, p = 0.01 and rhuEPO/ASA 127.2 ± 6.8, p = 0.02), whereas BP in rats from placebo/placebo (120.9 ± 5.0, p = 0.18) and placebo/ASA (124.6 ± 13.3, p = 0.12) groups remained unchanged. By direct measurement, the final BP was higher in rhuEPO/placebo (DBP 123.1 ± 12.0; SBP 157.4 ± 12.5; MBP 139.8 ± 11.9) than placebo/placebo (DBP 105.1 ± 11.5; SBP 141.0 ± 12.6; MBP 122.1 ± 12.1) and placebo/ASA groups (DBP 106.6 ± 8.1; SBP 141.5 ± 8.4, MBP 122.1 ± 7.2) (p < 0.05 by post hoc Bonferroni test ANOVA). The rhuEPO/ASA group (PAD 115.1 ± 11.4, PAS 147.4 ± 9.1, MBP 130.1 ± 10.3) was not different from other groups.

CONCLUSIONS

The administration of very high doses of rhuEPO is associated with an increase in hematocrit and BP in nonuremic rats. The concomitant use of ASA mitigates the rhuEPO-associated BP increase.

The effect of erythropoietin on anastomotic healing of irradiated rats

AIM

The aim of the present study is to evaluate the possible protective effects of erythropoietin (EPO) on anastomotic wound healing after preoperative radiotherapy according to its pleiotropic mechanism of action.

METHODS

Thirty-two male Wistar albino rats were randomized into four groups containing eight rats each: ANAS group, standard resection plus anastomosis; RT+ANAS group, radiation plus standard resection plus anastomosis; ANAS+EPO group, standard resection plus anastomosis plus EPO; RT+ANAS+EPO, radiation plus standard resection plus anastomosis plus EPO. All animals were sacrificed by cardiac puncture, and anastomotic healing was measured by bursting pressure, hydroxyproline (OHP) levels, myeloperoxidase (MPO) activity and histopathological evaluations. Malondialdehyde (MDA), tumor necrosis factor-alpha (TNF-α), and matrix metalloproteinase-9 (MMP-9) were also measured in serum specimens.

RESULTS

OHP levels in the RT+ANAS + EPO group were significantly increased compared with other groups (p < .05). In contrast, MPO activity in the RT+ANAS+EPO group was significantly decreased compared with other groups (p < .05). Serum MDA levels were found to be decreased in the ANAS+EPO and RT+ANAS+EPO groups (p < .05). Group comparisons demonstrated that bursting pressure was significantly higher in EPO treated rats (p < .05). The histopathology results revealed that EPO treatment improves anastomotic wound healing though decreased necrosis and inflammatory cell infiltration and increased fibroblast activity.

CONCLUSION

The findings of the present study indicate that EPO contributes to wound healing and the strength of colon anastomosis following radiation due to its antioxidant and anti-inflammatory effects, but further studies are needed to explore the significance of these effects.

What is causing the mortality in treating the anemia of chronic kidney disease: erythropoietin dose or hemoglobin level?

PURPOSE OF REVIEW

This article examines the potential mechanisms underlying adverse risk observed in four randomized controlled trials of anemia correction in chronic kidney disease (CKD) patients.

RECENT FINDINGS

The Normal Hematocrit Study, Cardiovascular Risk Reduction by Early Anemia Treatment with Epoetin-beta, Correction of Hemoglobin and Outcomes in Renal Insufficiency, and Trial to Reduce Cardiovascular Events with Aranesp Therapy demonstrate increased risk of mortality and/or cardiovascular complications with targeting of a higher hemoglobin (Hb) in CKD patients. Although a higher Hb level was targeted in these trials, erythropoiesis-stimulating agent (ESA) exposure itself might account for the observed increased risk. This is because, in these trials, achieving a normal or near normal Hb was associated with improved survival and reduced cardiovascular risk. Indeed, it was the 'targeting' of a higher Hb with ESA that seemed to be the problem. Observational data, although conflicting, on the whole provide support for high dosage of ESA being harmful but cannot, by their very nature, prove causality.

SUMMARY

After 20 years of ESA use, is it plausible that ESAs could be toxic? How does one reconcile conflicting observational data with a hypothesis that postulates ESA toxicity? Does the biology of erythropoietin provide a mechanistic explanation? The answers to these questions, among others, will be important in charting a future role for ESAs in treating CKD anemia.

Outcomes with the Use of Recombinant Human Erythropoietin in Critically Ill Burn Patients

Recent data demonstrate a possible mortality benefit in traumatically injured patients when given subcutaneous recombinant human erythropoietin (rhEPO). The purpose of this report is to examine the effect of rhEPO on mortality and transfusion in burn patients. We conducted a review of burn patients (greater than 30% total body surface area, intensive care unit [ICU] days greater than 15) treated with 40,000u rhEPO over an 18-month period (January 2007 to July 2008). Matched historical controls were identified and a contemporaneous cohort of subjects not administered rhEPO was used for comparison (NrhEPO). Mortality, transfusions, ICU and hospital length of stay were assessed. A total of 105 patients were treated (25 rhEPO, 53 historical control group, 27 NrhEPO). Hospital transfusions (mean 13,704 ± mL vs 13,308 ± mL; P = 0.42) and mortality (29.6 vs 32.0%; P = 0.64) were similar. NrhEPO required more blood transfusions (13,308 ± mL vs 6,827 ± mL; P = 0.004). No difference in mortality for the rhEPO and NrhEPO (32.0 vs 22.2%; P = 0.43) was found. Thromboembolic complications were similar in all three groups. No effect was seen for rhEPO treatment on mortality or blood transfusion requirements in the severely burned.

Improvement in Appropriate Utilization of Recombinant Human Erythropoietin Pre- and Post-Implementation of a Required Order Form

BACKGROUND:

Erythropoietin stimulating agents (ESAs) are high-cost medications that have a significant impact on many pharmacy budgets. Recently, ESAs have received stronger safety warnings and reimbursement has been curtailed by third-party payers including the Centers for Medicare and Medicaid Services. For these reasons, many hospitals are developing strategies to optimize their use. A required order form with acceptable indications and dosing was implemented at an academic medical center in an attempt to improve dosing and appropriate utilization of ESAs.

OBJECTIVE:

To determine whether implementation of a required order form increased appropriate use and/or decreased total utilization of recombinant human erythropoietin (rHuEPO).

METHODS:

This was a retrospective cohort study of rHuEPO utilization for 4 months pre- and 6 months post-implementation (April 2008-January 2009).

RESULTS:

Implementation of a required order form for rHuEPO resulted in significantly fewer patients receiving inappropriate doses of rHuEPO (51.3% vs 19.2%, p < 0.001). The number of patients treated, adjusted to hospital census, was also reduced after implementation of the order form (0.003 vs 0.004 pts./average pt. days, p = 0.03). Annual spending for rHuEPO was reduced by 47% during 2008 despite an increased acquisition cost.

CONCLUSIONS:

Implementation of a required order form with evidence-based dosing recommendations can be an effective strategy to improve appropriate utilization of rHuEPO.

The beta-hCG+erythropoietin in acute stroke (BETAS) study: a 3-center, single-dose, open-label, noncontrolled, phase IIa safety trial

BACKGROUND AND PURPOSE

Animal data suggest the use of beta-human chorionic gonadotropin followed by erythropoietin to promote brain repair after stroke. The current study directly translated these results by evaluating safety of this sequential growth factor therapy through a 3-center, single-dose, open-label, noncontrolled, Phase IIa trial.

METHODS

Patients with ischemic stroke 24 to 48 hours old and National Institutes of Health Stroke Scale score of 6 to 24 started a 9-day course of beta-human chorionic gonadotropin (once daily on Days 1, 3, and 5 of study participation) followed by erythropoietin (once daily on Days 7, 8, and 9 of study participation). This study also evaluated performance of serially measured domain-specific end points.

RESULTS

A total of 15 patients were enrolled. Two deaths occurred, neither related to study medications. No safety concerns were noted among clinical or laboratory measures, including screening for deep vein thrombosis and serial measures of serum hemoglobin. In several instances, domain-specific end points provided greater insight into impairments as compared with global outcome measures.

CONCLUSIONS

Results support the safety of this sequential, 2-growth factor therapy initiated 24 to 48 hours after stroke onset.

Translating the frontiers of brain repair to treatments: starting not to break the rules

The field of neural repair in stroke has identified cellular systems of reorganization and possible molecular mechanisms. Conceptual barriers now limit the generation of clinically useful agents. First, it is not clear what the causal mechanisms of neural repair are in stroke. Second, adequate delivery systems for neural repair drugs need to be determined for candidate molecules. Third, ad hoc applications of existing pharmacological agents that enhance attention, mood or arousal to stroke have failed. New approaches that specifically harness the molecular systems of learning and memory provide a new avenue for stroke repair drugs. Fourth, combinatorial treatments for neural repair need to be considered for clinical therapies. Finally, neural repair therapies have as a goal altering brain connections, cognitive maps and active neural networks. These actions may trigger a unique set of "neural repair side effects" that need to be considered in planning clinical trials.

Arterial hypertension induced by erythropoietin and erythropoiesis-stimulating agents (ESA)

This review summarizes the evidence for a hypertensinogenic effect of Erythropoietin (Epo) in normal human subjects and predialysis, hemodialysis, and continuous ambulatory peritoneal dialysis (CAPD) patients. The possible mechanisms of Epo-induced hypertension are examined with in vivo animal and in vitro data, as well as pathophysiological human studies in both normal subjects and CKD patients. The evidence for a hypertensinogenic effect of erythropoiesis-stimulating agents (ESAs) in normal subjects, predialysis CKD, hemodialysis, and CAPD patients is compelling. Epo increases BP directly and notably independently of its erythropoietic effect and its effect on blood rheology. The potential for the development of future agents that might act as specific stimulators of erythropoiesis, devoid of direct hemodynamic side effects is underscored.

Can we improve neurological outcomes in severe traumatic brain injury? Something old (early prophylactic hypothermia) and something new (erythropoietin)

Traumatic brain injury is a leading cause of mortality and long-term morbidity, particularly affecting young people. With our best therapies, one half of the patients with severe traumatic brain injury are never capable of living independently. Two interventions, which have real potential to improve neurological outcomes in patients with traumatic brain injury, are (i) very early induction of prophylactic hypothermia and (ii) exogenous erythropoietin therapy. There is substantial experimental evidence, a plausible biological rationale, and supportive clinical evidence from clinical trials to suggest a possible beneficial effect of prophylactic hypothermia and also for exogenous erythropoietin therapy in severe traumatic brain injury. Despite the recent guidelines and publications recommending these interventions, critical care clinicians should be conservative towards implementing these therapies outside clinical trials due to substantial efficacy and safety concerns. Nevertheless the high morbidity and mortality associated with severe traumatic brain injury (TBI) demands that we investigate the safety and efficacy of these promising potential therapies as a matter of urgency.

Hemoglobin target in chronic kidney disease: a pediatric perspective

Erythropoietin has transformed the treatment of the anemia of chronic kidney disease (CKD) by preventing the need for blood transfusions and improving the quality of life in all patients, including children. Anemia in children, in the age group 1-19 years, may be defined as hemoglobin (Hgb) levels < 12.1-13.5 g/dl for boys and < 11.4-11.5 g/dl for girls, based on the National Health and Nutrition Examination Survey (NHANES) norms. The prevalence of anemia in children ranges from 31.2% in stage 1 CKD to 93.3% in stages 4 and 5 CKD. The recent publication of trials evaluating the optimal hemoglobin level in adult CKD patients has generated considerable uncertainty about the target Hgb level in children with CKD. It is unclear whether generalizing of results from these trials in adults to children is appropriate. Adequately powered, randomized, controlled studies have not been conducted on children, and none to our knowledge are currently planned. The Food and Drug Administration (FDA) offers scant guidance on the Hgb target level for children, other than implying that it should be no different from that for adults. The purpose of this editorial is to critically scrutinize whether there is a benefit to the normalization of anemia in children with CKD and whether adoption of the results from adult studies is appropriate.

Hemoglobin variability in anemia of chronic kidney disease

Hemoglobin levels in individuals with chronic kidney disease fluctuate frequently above or below the recommended target levels within short periods of time even though the calculated mean hemoglobin remains within the target range of 11 to 12 g/dl. Both pharmacologic features and dosing of erythropoiesis-stimulating agents may lead to cyclic pattern of hemoglobin levels within the recommended range. Several longitudinal studies highlight the complexity of maintaining stable hemoglobin levels over time. As a consequence, patients may risk increased hospitalization and mortality, because both low and high hemoglobin levels are associated with increased cardiovascular events and death. The duration of time that hemoglobin remains higher or lower than the target thresholds may be important to adverse outcomes. It is not clear whether adverse effects of hemoglobin variability are because of the therapy with erythropoiesis-stimulating agents and/or iron or despite such a therapy. Several factors affect hemoglobin variability, including those that are drug related, such as pharmacokinetic parameters, patient-related differences in demographic characteristics, and factors affecting clinical status, as well as clinical practice guidelines, treatment protocols, and reimbursement policies. Strategies that consider each of these factors and reduce hemoglobin variability may be associated with improved clinical outcomes.

Temporal trends in red blood transfusion among US dialysis patients, 1992-2005

BACKGROUND

Studies addressing patterns and trends in red blood cell transfusion use in US hemodialysis patients surprisingly have received little attention in the last decade.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

Point prevalent (as of January 1 of each calendar year 1992 to 2005) dialysis patients with Medicare Part A and Part B as primary insurance (n = 77,347 in 1992, n = 164,933 in 2005). The 6 months preceding January 1 of each year were used to assemble a comorbidity profile based on administrative claims data.

PREDICTORS

Hemoglobin levels, patient characteristics, comorbid conditions.

OUTCOMES

Blood transfusion events obtained from Part A and Part B files using code files for both whole and packed red blood cell transfusions and hemoglobin levels.

MEASUREMENTS

Comorbid conditions were defined by the presence of 1 or more inpatient/outpatient institutional claims (inpatient hospitalization, skilled nursing facility, or home health agency), 2 or more outpatient or physician/supplier claims, or 1 or more outpatient and 1 or more physician/supplier claims for atherosclerotic heart disease, congestive heart failure, cerebrovascular accidents/transient ischemic attacks, peripheral vascular disease, other cardiovascular diseases, chronic obstructive pulmonary disease, gastrointestinal disorders, liver disease, arrhythmia, and diabetes mellitus.

RESULTS

Raw transfusion rates decreased in both outpatient and inpatient settings from 535.33/1,000 patient-years for 1992 prevalent dialysis patients to 263.65/1,000 patient-years in 2005 (P for trend < 0.001, 1992 versus 1999 and 1999 versus 2005). Adjusted rates decreased similarly. This phenomenon could not be explained by changes in case mix.

LIMITATIONS

Cause, effect, and confounding cannot be separated in this observational study. The accuracy of blood transfusion billing data is unknown. Temporal trends may be related to factors other than erythropoiesis-stimulating agent use.

CONCLUSION

Transfusion events in hemodialysis patients decreased more than 2-fold from 1992 to 2005; most of the decrease occurred in the first 5 years after erythropoietin was introduced.

Anemia and heart failure: a cause of progression or only a consequence?

Anemia is one of the most frequent co-morbidities in the patients with heart failure. Its prevalence increases from 4-7% in the subjects with asymptomatic left ventricular dysfunction to >30% in the patients with severe heart failure. Renal insufficiency, activation of inflammatory mediators, and treatment with renin-angiotensin antagonists seem to be its main determinants. The results of many studies agree in showing that anemia is a powerful independent determinant of survival in patients with heart failure. However, the mechanisms of this relation are still incompletely understood. Moreover a favourable effect on prognosis of the correction of anemia has not been shown, yet, and also controlled studies assessing its effects on exercise tolerance have yielded controversial results.