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

A fully human anti-BMP6 antibody reduces the need for erythropoietin in rodent models of the anemia of chronic disease

Recombinant erythropoietin (EPO) and iron substitution are a standard of care for treatment of anemias associated with chronic inflammation, including anemia of chronic kidney disease. A black box warning for EPO therapy and concerns about negative side effects related to high-dose iron supplementation as well as the significant proportion of patients becoming EPO resistant over time explains the medical need to define novel strategies to ameliorate anemia of chronic disease (ACD). As hepcidin is central to the iron-restrictive phenotype in ACD, therapeutic approaches targeting hepcidin were recently developed. We herein report the therapeutic effects of a fully human anti-BMP6 antibody (KY1070) either as monotherapy or in combination with Darbepoetin alfa on iron metabolism and anemia resolution in 2 different, well-established, and clinically relevant rodent models of ACD. In addition to counteracting hepcidin-driven iron limitation for erythropoiesis, we found that the combination of KY1070 and recombinant human EPO improved the erythroid response compared with either monotherapy in a qualitative and quantitative manner. Consequently, the combination of KY1070 and Darbepoetin alfa resulted in an EPO-sparing effect. Moreover, we found that suppression of hepcidin via KY1070 modulates ferroportin expression on erythroid precursor cells, thereby lowering potentially toxic-free intracellular iron levels and by accelerating erythroid output as reflected by increased maturation of erythrocyte progenitors. In summary, we conclude that treatment of ACD, as a highly complex disease, becomes more effective by a multifactorial therapeutic approach upon mobilization of endogenous iron deposits and stimulation of erythropoiesis.

Impact of immediate post-transplant parenteral iron therapy on the prevalence of anemia and short-term allograft function in a cohort of pediatric and adolescent renal transplant recipients

Anemia is common but under-diagnosed and often inadequately treated in KTX recipients. ID is the major cause of early-onset anemia. We introduced routine use of parenteral (IV) iron in patients (2-18 years) who had KTX between January 2011 and December 2015. We explored the clinical benefits of this practice by comparing the iron-treated subjects [TX] with historical controls who had KTX between 2005 and 2010. The prevalence of anemia at 6 months (early-onset) for the cohort (both the study group and controls) was 55% and for anemia at 12 months (late-onset) was 60%. Although cause-effect relationship may not be proven in a retrospective study design, there was a significant greater frequency of ID and anemia at 3 (P < .02) and 6 months (P < .04), and a reduced allograft function (eGFR < 60 mL/min/1.73 m² ) at 12 (P = .03) and 24 months (P = .04) of KTX in the control arm. Furthermore, a greater proportion of the control arm required either ESA (P = .03) or blood transfusion (P = .04) as a rescue treatment for moderate-to-severe anemia. In conclusion, routine parenteral iron treatment was associated with a lower prevalence of early- and late-onset anemia, and a lower requirement for either ESA rescue or blood transfusion.

Contemporary management of anaemia, erythropoietin resistance and cardiovascular risk in patients with advanced chronic kidney disease: a nationwide analysis

BACKGROUND

Optimal management of chronic kidney disease (CKD) anaemia remains controversial and few studies have evaluated real-world management of anaemia in advanced CKD in the context of guideline recommendations.

METHODS

We performed an observational study from the Swedish Renal Registry evaluating the epidemiology and treatment patterns of anaemia across Stages 3b-5 in non-dialysis (ND) and dialysis-dependent (DD) CKD patients during 2015. Logistic regression and Cox models explored the associations between anaemia treatments, inflammation, erythropoietin resistance index (ERI) and subsequent 1-year risk of major adverse cardiovascular events (MACEs).

RESULTS

Data from 14 415 (ND, 11 370; DD, 3045) patients were included. Anaemia occurred in 60% of ND and 93% of DD patients. DD patients used more erythropoiesis-stimulating agents (ESAs; 82% versus 24%) and iron (62% versus 21%) than ND patients. All weekly ESA doses were converted to a weight-adjusted weekly epoetin equivalent dose. The prescribed ESA doses were low to moderate [median 48.2 IU/kg/week (ND), 78.6 IU/kg/week (DD)]. Among ESA-treated patients, 6-21% had haemoglobin (Hb) >13 g/dL and 2-6% had Hb <9 g/dL. Inflammation (C-reactive protein >5 mg/L) was highly prevalent and associated with ERI and higher ESA doses. Higher (>88 IU/kg/week) versus lower (<44 IU/kg/week) ESA doses were associated with a higher risk of MACEs [{ND hazard ratio [HR] 1.36 [95% confidence interval (CI) 1.00-1.86]; DD HR 1.60 [95% CI 1.24-2.06]}. There was no association between iron use and inflammation or MACEs.

CONCLUSIONS

Anaemia remains highly prevalent in advanced CKD. Patients with anaemia received moderate ESA doses with a relatively low prevalence of iron use. Higher doses of ESA were associated with inflammation and a higher risk of MACE.

Atypical memory B-cells and autoantibodies correlate with anemia during Plasmodium vivax complicated infections

Malaria caused by Plasmodium vivax is a highly prevalent infection world-wide, that was previously considered mild, but complications such as anemia have been highly reported in the past years. In mice models of malaria, anti-phosphatidylserine (anti-PS) autoantibodies, produced by atypical B-cells, bind to uninfected erythrocytes and contribute to anemia. In human patients with P. falciparum malaria, the levels of anti-PS, atypical B-cells and anemia are strongly correlated to each other. In this study, we focused on assessing the relationship between autoantibodies, different B-cell populations and hemoglobin levels in two different cohorts of P. vivax patients from Colombia, South America. In a first longitudinal cohort, our results show a strong inverse correlation between different IgG autoantibodies tested (anti-PS, anti-DNA and anti-erythrocyte) and atypical memory B-cells (atMBCs) with hemoglobin in both P. vivax and P. falciparum patients over time. In a second cross-sectional cohort, we observed a stronger relation between hemoglobin levels, atMBCs and autoantibodies in complicated P. vivax patients compared to uncomplicated ones. Altogether, these data constitute the first evidence of autoimmunity associating with anemia and complicated P. vivax infections, suggesting a role for its etiology through the expansion of autoantibody-secreting atMBCs.

Malaria is one of the top global infections causing high mortality and morbidity every year. Plasmodium vivax is the most prevalent malarial infection, particularly in the region of the Americas. Complications associated with P. vivax, such as anemia, are a growing reported phenomenon, but the mechanisms leading to them are poorly understood. Here, we report the first evidence of autoantibodies and Atypical Memory B-cells correlating with anemia in two different cohorts of P. vivax patients, particularly during complicated infections. These findings point to Atypical Memory B-cells as key pathological players, possibly through the secretion of autoantibodies, and attributes a role for autoimmunity in mediating complications during P. vivax infections.

Therapeutic targets for the anemia of predialysis chronic kidney disease: a meta-analysis of randomized, controlled trials

Anemia is one of the major complications in predialysis patients with chronic kidney disease (CKD). A clearer cognition of the prognostic impact of hemoglobin (Hb) or hematocrit (Hct) target on the outcomes of predialysis patients with CKD is significant. This article aims to establish the suitable hemoglobin target to provide clinical guidance. MEDLINE, EmBase, the Cochrane Library and other databases were searched with both MeSH terms and keywords to gather researches that assessed all-cause mortality, stroke, treatment of renal replacement, and transfusion. The meta-analysis was accomplished via Revman 5.3 version. Totally, 13 eligible studies involving 7606 patients were included. There was a significantly lower risk of transfusion (risk ratio (RR) 0.59, 95% CI 0.52 to 0.67; p<0.00001) in the higher hemoglobin group than in the lower one. However, no significant difference was found in all-cause mortality (RR 1.10, 95% CI 0.98 to 1.23; p=0.11), stroke (RR 1.32, 95% CI 0.82 to 2.10; p=0.25) and treatment of renal replacement including hemodialysis, peritoneal dialysis and renal transplant (RR 1.08, 95% CI 0.95 to 1.22; p= 0.23) between the higher hemoglobin group and the lower one. The results favor the higher hemoglobin target. To target the higher hemoglobin when treating predialysis patients with CKD may decrease the risk of transfusion without increasing the risk of death, stoke, and treatment of renal replacement.

Hemoglobin targets for the anemia in patients with dialysis-dependent chronic kidney disease: a meta-analysis of randomized, controlled trials

BACKGROUND

Anemia is extremely common among dialysis patients and underlies some of the symptoms associated with reduced kidney function, including fatigue, depression, reduced exercise tolerance, and dyspnea.

OBJECTIVES

A clearer cognition of the prognosistic impact of hemoglobin (Hb) or hematocrit (Hct) target for the outcomes of dialysis patients is urgent. This article aims to establish the suitable hemoglobin in order to provide clinical guidance.

METHODS

MEDLINE, EmBase, the Cochrane Library and other databases were searched with both MeSH terms and keywords to gather randomized controlled trials that assessed all-cause mortality, cardiovascular events, fistula thrombosis, infectious diseases and transfusion among dialysis-dependent patients using erythropoiesis-stimulating agents. The meta-analysis was accomplished via Revman 5.3 version.

FINDINGS

Totally, nine eligible studies were included, with study subjects involving 3228 patients. There was a significantly higher risk of fistula thrombosis without heterogeneity (RR 1.34, 95% CI 1.15-1.55; p < 0.05) in the higher Hb target group than in the lower Hb target group in the fixed effects model. However, no significant difference was found in all-cause mortality in the fixed effects model (RR 1.09, 95% CI 0.93-1.27; p = 0.30), cardiovascular events (RR 0.77, 95% CI 0.31-1.92; p = 0.58), infectious diseases (RR 0.69, 95% CI 0.24-1.96; p = 0.49) and transfusion (RR 0.92, 95% CI 0.42-1.99; p = 0.82) in the random effects model between the higher Hb target group and the lower Hb target group.

DISCUSSION

The results favor lower Hb target. To target lower Hb target when treating dialysis patients with anemia may decrease the risk of fistula thrombosis without increasing the risk of death, cardiovascular events, infectious diseases and transfusion.

Hypothyroidism is associated with all-cause mortality in a national cohort of chronic haemodialysis patients

AIM

The prevalence of hypothyroidism is high in haemodialysis (HD) patients and hypothyroidism increases all-cause mortality in HD patients. Comorbidities are common in HD patients and are associated with both mortality and hypothyroidism. The aim of the study is to explore the effect of the interactions of comorbidities and hypothyroidism on all-cause mortality in HD patients.

METHOD

Patients with hypothyroidism (ICD-9-CM 244.0, 244.1, and 244.9) and matched patients without hypothyroidism in the Registry for Catastrophic Illness Patient Database of Taiwan Health Insurance from 2000 to 2010 were analyzed. The association of hypothyroidism and risk of all-cause mortality was analyzed using Cox proportional hazard regression.

RESULT

Nine hundred and eight HD patients with hypothyroidism and 3632 sex-, age-, gender- matched HD patients without hypothyroidism were analyzed. Hypothyroidism was associated with increased all-cause mortality with an adjusted hazard ratio of 1.22 [95% confidence interval (CI): 1.10-1.36, P < 0.001]. TRT may decrease mortality associated with hypothyroidism (P < 0.001). There was a significant interaction (P = 0.04) between diabetes and hypothyroidism. There was no significant interaction found in hypothyroidism and the following comorbidities: hyperlipidaemia, hypertension, chronic obstructive pulmonary disease, coronary artery disease, stroke, peripheral arterial disease, asthma, congestive heart failure and cancer.

CONCLUSION

Hypothyroidism is associated with increased all-cause mortality in chronic HD patients. The interaction of hypothyroidism and diabetes, but not other common comorbidities in HD patients, has an effect on mortality risks.

Eryptosis - the Neglected Cause of Anemia in End Stage Renal Disease

End stage renal disease (ESRD) invariably leads to anemia which has been mainly attributed to compromised release of erythropoietin from the defective kidneys with subsequent impairment of erythropoiesis. However, erythropoietin replacement only partially reverses anemia pointing to the involvement of additional mechanisms. As shown more recently, anemia of ESRD is indeed in large part a result of accelerated erythrocyte loss due to suicidal erythrocyte death or eryptosis, characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the cell surface. Phosphatidylserine exposing erythrocytes are bound to and engulfed by macrophages and are thus rapidly cleared from circulating blood. If the loss of erythrocytes cannot be fully compensated by enhanced erythropoiesis, stimulation of eryptosis leads to anemia. Eryptotic erythrocytes may further adhere to the vascular wall and thus impair microcirculation. Stimulators of eryptosis include complement, hyperosmotic shock, energy depletion, oxidative stress, and a wide variety of xenobiotics. Signaling involved in the stimulation of eryptosis includes increase of cytosolic Ca2+ activity, ceramide, caspases, calpain, p38 kinase, protein kinase C, Janus-activated kinase 3, casein kinase 1α, and cyclin-dependent kinase 4. Eryptosis is inhibited by AMP-activated kinase, p21-activated kinase 2, cGMP-dependent protein kinase, mitogen- and stress-activated kinase MSK1/2, and some illdefined tyrosine kinases. In ESRD eryptosis is stimulated at least in part by a plasma component, as it is triggered by exposure of erythrocytes from healthy individuals to plasma from ESRD patients. Several eryptosis-stimulating uremic toxins have been identified, such as vanadate, acrolein, methylglyoxal, indoxyl sulfate, indole-3-acetic acid and phosphate. Attempts to fully reverse anemia in ESRD with excessive stimulation of erythropoiesis enhances the number of circulating suicidal erythrocytes and bears the risk of interference with micocirculation, At least in theory, anemia in ESRD could preferably be treated with replacement of erythropoietin and additional inhibition of eryptosis thus avoiding eryptosis-induced impairment of microcirculation. A variety of eryptosis inhibitors have been identified, their efficacy in ESRD remains, however, to be shown.

Therapeutic effect of erythropoietin in patients with traumatic brain injury: a meta-analysis of randomized controlled trials

OBJECTIVE

Erythropoietin (EPO) exerts a neuroprotective effect in animal models of traumatic brain injury (TBI). However, its effectiveness in human patients with TBI is unclear. In this study, the authors conducted the first meta-analysis to assess the effectiveness and safety of EPO in patients with TBI.

METHODS

In December 2015, a systematic search was performed of PubMed, Web of Science, MEDLINE, Embase, the Cochrane Library databases, and Google Scholar. Only English-language publications of randomized controlled trials (RCTs) using EPO in patients with TBI were selected for analysis. The assessed outcomes included mortality, favorable neurological outcome, hospital stay, and associated adverse effects. Continuous variables were presented as mean difference (MD) with a 95% confidence interval (CI). Dichotomous variables were presented as risk ratio (RR) or risk difference (RD) with a 95% CI. Statistical heterogeneity was examined using both I2 and chi-square tests.

RESULTS

Of the 346 studies identified in the search, 5 RCTs involving 915 patients met the inclusion criteria. The overall results demonstrated that EPO significantly reduced mortality (RR 0.69, 95% CI 0.49–0.96, p = 0.03) and shortened the hospitalization time (MD −7.59, 95% CI −9.71 to −5.46, p < 0.0001) for patients with TBI. Pooled results of favorable outcome (RR 1.00, 95% CI 0.88–1.15, p = 0.97) and deep vein thrombosis (DVT; RD 0.00, 95% CI −0.05 to 0.05, p = 1.00) did not show a significant difference.

CONCLUSIONS

The authors suggested that EPO is beneficial for patients with TBI in terms of reducing mortality and shortening hospitalization time without increasing the risk of DVT. However, its effect on improving favorable neurological outcomes did not reach statistical significance. Therefore, more well-designed RCTs are necessary to ascertain the optimum dosage and time window of EPO treatment for patients with TBI.

The Cost-Effectiveness of Anemia Treatment for Persons with Chronic Kidney Disease

BACKGROUND

Although major guidelines uniformly recommend iron supplementation and erythropoietin stimulating agents (ESAs) for managing chronic anemia in persons with chronic kidney disease (CKD), there are differences in the recommended hemoglobin (Hb) treatment target and no guidelines consider the costs or cost-effectiveness of treatment. In this study, we explored the most cost-effective Hb target for anemia treatment in persons with CKD stages 3-4.

METHODS AND FINDINGS

The CKD Health Policy Model was populated with a synthetic cohort of persons over age 30 with prevalent CKD stages 3-4 (i.e., not on dialysis) and anemia created from the 1999-2010 National Health and Nutrition Examination Survey. Incremental cost-effectiveness ratios (ICERs), computed as incremental cost divided by incremental quality adjusted life years (QALYs), were assessed for Hb targets of 10 g/dl to 13 g/dl at 0.5 g/dl increments. Targeting a Hb of 10 g/dl resulted in an ICER of $32,111 compared with no treatment and targeting a Hb of 10.5 g/dl resulted in an ICER of $32,475 compared with a Hb target of 10 g/dl. QALYs increased to 4.63 for a Hb target of 10 g/dl and to 4.75 for a target of 10.5 g/dl or 11 g/dl. Any treatment target above 11 g/dl increased medical costs and decreased QALYs.

CONCLUSIONS

In persons over age 30 with CKD stages 3-4, anemia treatment is most cost-effective when targeting a Hb level of 10.5 g/dl. This study provides important information for framing guidelines related to treatment of anemia in persons with CKD.

The Safety of Erythropoiesis-Stimulating Agents for the Treatment of Anemia Resulting from Chronic Kidney Disease

Chronic kidney disease (CKD) anemia treatment was revolutionized in the late 1980s with the introduction of recombinant human erythropoietin. This and related erythropoiesis-stimulating agents (ESAs) greatly benefited patients by decreasing debilitating symptoms, improving their quality of life, and freeing them from dependence on blood transfusions with their associated complications such as infections, sensitization impeding transplantation, and secondary iron overload. However, even in the initial studies, untoward effects were noted in patients receiving ESAs, including worsening hypertension, seizures, and dialysis access clotting. Later, increased mortality, malignancy progression and even stroke were reported in renal patients. This review focuses on the safety issues of ESAs in CKD patients.

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.

Thyroid functional disease: an under-recognized cardiovascular risk factor in kidney disease patients

Thyroid functional disease, and in particular hypothyroidism, is highly prevalent among chronic kidney disease (CKD) and end-stage renal disease (ESRD) patients. In the general population, hypothyroidism is associated with impaired cardiac contractility, endothelial dysfunction, atherosclerosis and possibly higher cardiovascular mortality. It has been hypothesized that hypothyroidism is an under-recognized, modifiable risk factor for the enormous burden of cardiovascular disease and death in CKD and ESRD, but this has been difficult to test due to the challenge of accurate thyroid functional assessment in uremia. Low thyroid hormone levels (i.e. triiodothyronine) have been associated with adverse cardiovascular sequelae in CKD and ESRD patients, but these metrics are confounded by malnutrition, inflammation and comorbid states, and hence may signify nonthyroidal illness (i.e. thyroid functional test derangements associated with underlying ill health in the absence of thyroid pathology). Thyrotropin is considered a sensitive and specific thyroid function measure that may more accurately classify hypothyroidism, but few studies have examined the clinical significance of thyrotropin-defined hypothyroidism in CKD and ESRD. Of even greater uncertainty are the risks and benefits of thyroid hormone replacement, which bear a narrow therapeutic-to-toxic window and are frequently prescribed to CKD and ESRD patients. In this review, we discuss mechanisms by which hypothyroidism adversely affects cardiovascular health; examine the prognostic implications of hypothyroidism, thyroid hormone alterations and exogenous thyroid hormone replacement in CKD and ESRD; and identify areas of uncertainty related to the interplay between hypothyroidism, cardiovascular disease and kidney disease requiring further investigation.

Association of thyroid functional disease with mortality in a national cohort of incident hemodialysis patients

CONTEXT

Hypothyroidism is a common condition that disproportionately affects hemodialysis patients. In the general population, hypothyroidism is associated with higher mortality, particularly in populations with underlying cardiovascular risk. Despite their heightened cardiovascular mortality, the impact of hypothyroidism on the survival of hemodialysis patients remains uncertain.

OBJECTIVE

To examine whether hypothyroidism is independently associated with higher mortality in hemodialysis patients.

DESIGN, SETTING, AND PATIENTS

Among 8840 incident hemodialysis patients receiving care from a large national dialysis provider from January 2007 to December 2011, we examined the association of hypothyroidism (TSH >5.0 mIU/L) with mortality.

MAIN OUTCOME MEASURES

Associations between baseline and time-dependent hypothyroidism with all-cause mortality were determined using case-mix adjusted Cox models. In secondary analyses, we examined the impact of low-normal, upper-normal, subclinical range, and overt range TSH levels (TSH ≥ 0.5-3.0, >3.0-5.0, >5.0-10.0, and >10.0 mIU/L, respectively) on mortality risk.

RESULTS

The study population consisted of 1928 (22%) hypothyroid and 6912 (78%) euthyroid patients. Baseline and time-dependent hypothyroidism were associated with higher mortality: adjusted hazard ratios (95% confidence intervals) were 1.47 (1.34-1.61) and 1.62 (1.45-1.80), respectively. Compared to low-normal TSH, upper-normal, subclinical hypothyroid, and overt hypothyroid TSH levels were associated with incrementally higher adjusted death risk in baseline and time-dependent analyses. In time-dependent analyses, the hypothyroidism-mortality association was increasingly stronger across higher body mass index strata.

CONCLUSIONS

Hypothyroidism as well as upper-normal TSH levels are associated with higher mortality in hemodialysis patients. Further studies are needed to determine whether restoration of TSH to low-normal levels with thyroid hormone replacement therapy ameliorates adverse outcomes in hemodialysis patients.

Suicidal erythrocyte death in end-stage renal disease

Anemia in end-stage renal disease (ESRD) results mainly from erythropoietin and iron deficiency. Anemia could be confounded, however, by accelerated clearance of circulating erythrocytes because of premature suicidal erythrocyte death or eryptosis characterized by phosphatidylserine exposure at the erythrocyte surface. Triggers of eryptosis include increased cytosolic Ca(2+) concentration ([Ca(2+)]i), oxidative stress, and ceramide. The present study explored whether and how ESRD influences eryptosis. Blood was drawn from healthy volunteers (n = 20) as well as ESRD patients (n = 20) prior to and after hemodialysis. Phosphatidylserine exposure was estimated from annexin V binding, [Ca(2+)]i from Fluo3-fluorescence, reactive oxygen species (ROS) from 2',7'dichlorodihydrofluorescein fluorescence, and ceramide from fluorescein-isothiocyanate-conjugated antibody binding in flow cytometry. Measurements were made in erythrocytes from freshly drawn blood and in erythrocytes from healthy volunteers exposed in vitro for 24 h to plasma from healthy volunteers or ESRD patients prior to and following dialysis. The patients suffered from anemia (hemoglobin 10.1 ± 0.5 g/100 ml) despite 1.96 ± 0.34 % reticulocytes. The percentage of phosphatidylserine-exposing erythrocytes was significantly higher in ESRD patients (0.84 ± 0.09 %) than in healthy volunteers (0.43 ± 0.04 %) and was significantly increased immediately after dialysis (1.35 ± 0.13 %). The increase in phosphatidylserine exposure was paralleled by increase in [Ca(2+)]i, oxidative stress, and ceramide abundance. As compared to addition of plasma from healthy individuals, addition of predialytic but not of postdialytic plasma from ESRD patients increased phosphatidylserine exposure, [Ca(2+)]i, ROS, and ceramide abundance. In conclusion, both, dialyzable components of uremic plasma and dialysis procedure, trigger eryptosis at least in part by increasing erythrocyte [Ca(2+)]i, ROS, and ceramide formation.

KEY MESSAGES

Anemia in uremia results in part from eryptosis, the suicidal erythrocyte death. Eryptosis in uremia is triggered in part by a dialyzable plasma component. Eryptosis in uremia is further triggered by dialysis procedure. Eryptosis in uremia is in part due to increased cytosolic Ca(2+) concentration. Eryptosis in uremia is further due to oxidative stress and ceramide formation.

Stimulation of suicidal erythrocyte death by increased extracellular phosphate concentrations

BACKGROUND/AIM

Anemia in renal insufficiency results in part from impaired erythrocyte formation due to erythropoietin and iron deficiency. Beyond that, renal insufficiency enhances eryptosis, the suicidal erythrocyte death characterized by phosphatidylserine-exposure at the erythrocyte surface. Eryptosis may be stimulated by increase of cytosolic Ca(2+)-activity ([Ca(2+)]i). Several uremic toxins have previously been shown to stimulate eryptosis. Renal insufficiency is further paralleled by increase of plasma phosphate concentration. The present study thus explored the effect of phosphate on erythrocyte death.

METHODS

Cell volume was estimated from forward scatter, phosphatidylserine-exposure from annexin V binding, and [Ca(2+)]i from Fluo3-fluorescence.

RESULTS

Following a 48 hours incubation, the percentage of phosphatidylserine exposing erythrocytes markedly increased as a function of extracellular phosphate concentration (from 0-5 mM). The exposure to 2 mM or 5 mM phosphate was followed by slight but significant hemolysis. [Ca(2+)]i did not change significantly up to 2 mM phosphate but significantly decreased at 5 mM phosphate. The effect of 2 mM phosphate on phosphatidylserine exposure was significantly augmented by increase of extracellular Ca(2+) to 1.7 mM, and significantly blunted by nominal absence of extracellular Ca(2+), by additional presence of pyrophosphate as well as by presence of p38 inhibitor SB203580.

CONCLUSION

Increasing phosphate concentration stimulates erythrocyte membrane scrambling, an effect depending on extracellular but not intracellular Ca(2+) concentration. It is hypothesized that suicidal erythrocyte death is triggered by complexed CaHPO4.

Diagnosis and treatment of cancer-related anemia

Cancer-related anemia (CRA) is due to multiple etiologies, including chemotherapy-induced myelosuppression, blood loss, functional iron deficiency, erythropoietin deficiency due to renal disease, marrow involvement with tumor as well as other factors. The most common treatment options for CRA include iron therapy, erythropoietic-stimulating agents (ESAs), and red cell transfusion. Safety concerns as well as restrictions and reimbursement issues surrounding ESA therapy for CRA have resulted in suboptimal treatment. Similarly, many clinicians are not familiar or comfortable using intravenous iron products to treat functional iron deficiency associated with CRA. This article summarizes our approach to treating CRA and discusses commonly encountered clinical scenarios for which current clinical guidelines do not apply.

Effect of erythropoiesis-stimulating agents on blood pressure in pre-dialysis patients

Introduction

Erythropoiesis-Stimulating Agents (ESA) are hypothesized to increase cardiovascular mortality in patients with chronic kidney disease. One of the proposed mechanisms is the elevation of blood pressure (BP) by ESA. Therefore, we aimed to determine whether the use of ESA was associated with antihypertensive treatment and higher BP.

Materials and Methods

In this cohort 502 incident pre-dialysis patients were included who started specialized pre-dialysis care in 25 clinics in the Netherlands. Data on medication including ESA use and dose, co-morbidities and BP were routinely collected every 6 months. Antihypertensive treatment and BP were compared for patients with and without ESA at baseline. Differences in antihypertensive medication and BP during pre-dialysis care were estimated with linear mixed models adjusted for age, sex, body mass index, cardiovascular disease, diabetes mellitus and estimated glomerular filtration rate.

Results

At baseline, 95.6% of patients with ESA were treated with antihypertensive medication and 73.1% of patients without ESA. No relevant difference in BP was found. During pre-dialysis care patients with ESA used 0.77 (95% CI 0.63;0.91) more classes of antihypertensive drugs. The adjusted difference in systolic blood pressure (SBP) was −0.3 (95% CI −2.7;2.0) mmHg and in diastolic blood pressure (DBP) was −1.0 (95% CI −2.1;0.3) mmHg for patients with ESA compared to patients without ESA. Adjusted SBP was 3.7 (95% CI −1.6;9.0) mmHg higher in patients with a high ESA dose compared to patients with a low ESA dose.

Conclusions

Our study confirms the hypertensive effect of ESA, since ESA treated patients received more antihypertensive agents. However, no relevant difference in BP was found between patients with and without ESA, thus the increase in BP seems to be controlled for by antihypertensive medication.

Incremental cost effectiveness of pharmacist-managed erythropoiesis-stimulating agent clinics for non-dialysis-dependent chronic kidney disease patients

BACKGROUND

Pharmacists successfully manage patients with anemia and chronic kidney disease (CKD), but the cost effectiveness of these programs is unknown.

OBJECTIVE

To compare the cost effectiveness of pharmacist-managed erythropoiesis-stimulating agent (ESA) clinics with that of usual care in patients with non-dialysis-dependent (NDD)-CKD.

METHODS

A Markov model was used to estimate the incremental cost effectiveness of pharmacist-managed ESA clinics compared with usual care in outpatient veterans receiving ESAs for NDD-CKD in 2009. The analysis was conducted from a US Veterans Health Administration perspective with a 5-year time horizon, and the year of valuation for cost results was 2012. The effect of parameter uncertainty was explored in one-way and probabilistic sensitivity analyses.

RESULTS

In the deterministic base case analysis, costs and effectiveness per patient over 5 years were US$13,412 and 2.096 quality-adjusted life-years (QALYs) in the pharmacist-managed ESA clinics and US$16,173 and 2.093 QALYs in usual care; ESA clinics dominated usual care. In one-way sensitivity analyses, ESA clinics no longer dominated if their patients' probability of being in the target hemoglobin range fell to 52 % (base case 71 %) or if the mean cost/patient/month of epoetin or darbepoetin in ESA clinics increased to approximately US$382 (base case US$226) or US$477 (base case US$268), respectively. When all parameters were varied simultaneously in a probabilistic sensitivity analysis, ESA clinics were favored ≥80 % of the time at willingness-to-pay thresholds of US$0-$100,000 per QALY gained.

CONCLUSIONS

Pharmacist-managed ESA clinics were less costly and more effective than usual care in patients receiving ESAs for anemia and NDD-CKD. Results were robust to variation and support the use of pharmacist-managed ESA clinics.

Triggering of suicidal erythrocyte death by uremic toxin indoxyl sulfate

Background

Anemia in end stage renal disease is attributed to impaired erythrocyte formation due to erythropoietin and iron deficiency. On the other hand, end stage renal disease enhances eryptosis, the suicidal erythrocyte death characterized by cell shrinkage and phosphatidylserine-exposure at the erythrocyte surface. Eryptosis may be triggered by increase of cytosolic Ca²⁺-activity ([Ca²⁺]_i) and by ceramide, which sensitizes erythrocytes to [Ca²⁺]_i. Mechanisms triggering eryptosis in endstage renal disease remained enigmatic. The present study explored the effect of indoxyl sulfate, an uremic toxin accumulated in blood of patients with chronic kidney disease.

Methods

Cell volume was estimated from forward scatter, phosphatidylserine-exposure from annexin V binding, ceramide abundance by specific antibodies, hemolysis from hemoglobin release, and [Ca²⁺]_i from Fluo3-fluorescence.

Results

A 48 hours exposure to indoxyl sulfate significantly increased [Ca²⁺]_i (≥ 300 μM), significantly decreased forward scatter (≥ 300 μM) and significantly increased annexin-V-binding (≥ 50 μM). Indoxyl sulfate (150 μM) induced annexin-V-binding was virtually abolished in the nominal absence of extracellular Ca²⁺. Indoxyl sulfate (150 μM) further enhanced ceramide abundance.

Conclusion

Indoxyl sulfate stimulates suicidal erythrocyte death or eryptosis, an effect in large part due to stimulation of extracellular Ca²⁺entry with subsequent stimulation of cell shrinkage and cell membrane scrambling.

Erythropoiesis-stimulating agent resistance and mortality in hemodialysis and peritoneal dialysis patients

Background

Responsiveness to erythropoiesis-stimulating agents (ESAs) varies widely among dialysis patients. ESA resistance has been associated with mortality in hemodialysis (HD) patients, but in peritoneal dialysis (PD) patients data is limited. Therefore we assessed the relation between ESA resistance in both HD and PD patients.

Methods

NECOSAD is a Dutch multi-center prospective cohort study of incident dialysis patients who started dialysis between January 1997 and January 2007. ESA resistance was defined as hemoglobin level < 11 g/dL with an above median ESA dose (i.e. 8,000 units/week in HD and 4,000 units/week in PD patients). Unadjusted and adjusted Cox regression analysis for all-cause 5-year mortality was performed for HD and PD patients separately.

Results

1013 HD and 461 PD patients were included in the analysis. ESA resistant HD patients had an adjusted hazard ratio of 1.37 (95% CI 1.04-1.80) and ESA resistant PD patients had an adjusted hazard ratio of 2.41 (1.27-4.57) as compared to patients with a good response.

Conclusions

ESA resistance, as defined by categories of ESA and Hb, is associated with increased mortality in both HD and PD patients. The effect of ESA resistance, ESA dose and hemoglobin are closely related and the exact mechanism remains unclear. Our results strengthen the need to investigate and treat causes of ESA resistance not only in HD, but also in PD patients.

Role of alpha-lipoic acid in the management of anemia in patients with chronic renal failure undergoing hemodialysis

INTRODUCTION

Anemia associated with chronic kidney disease is a serious complication necessitating expenditure of huge medical efforts and resources. This study investigates the role of alpha-lipoic acid (ALA) in end stage renal disease patients undergoing hemodialysis. By the virtue of its antioxidative effects, ALA is expected to act as an erythropoietin (EPO) adjuvant, and also has extended beneficial effects on endothelial dysfunction.

METHODS

Forty-four patients undergoing hemodialysis and receiving EPO were randomized into two groups: the first group received ALA 600 mg once daily for 3 months; while the other group represented the control group. Parameters measured at baseline and at end of study were hemoglobin, EPO doses, EPO resistance index (ERI), iron store indices, malondialdehyde, oxidized low-density lipoprotein (ox-LDL), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and asymmetric dimethylarginine (ADMA), as well as routine laboratory follow-up.

RESULTS

EPO doses and ERI were significantly decreased in the treatment group, while they did not change in the control group. Hemoglobin, iron store indices, malondialdehyde, oxidized ox-LDL, IL-6, TNF-α, and ADMA were similar in both treatment and control groups at baseline, and did not change by the end of study period. Likewise, routine laboratory measures were not affected by the treatment.

CONCLUSION

ALA could be used in hemodialysis patients to reduce requirements for EPO. However, larger and longer term studies are required to clarify the exact role of ALA in hemodialysis as well as in pre-hemodialysis patients.

Anaemia management and mortality risk in chronic kidney disease

Renal anaemia is a frequent complication in patients with chronic kidney disease (CKD). Severe anaemia (haemoglobin <90 g/l) is associated with increased risks of mortality and cardiac complications, such as left ventricular hypertrophy and cardiovascular disease, and impaired quality of life. Randomized controlled trials have tested the hypothesis that increasing haemoglobin level using erythropoiesis-stimulating agents (ESAs) lowers these risks and improves quality of life. Use of ESAs to normalize haemoglobin levels (to ≥130 g/l) versus the partial correction of anaemia (to haemoglobin levels of 90-110 g/l) has repeatedly been shown to have no cardiac benefit and to be associated with no incremental improvement in outcomes and quality of life (except fatigue), but has been shown to be associated with an increased risk of cardiovascular events and death. Use of more-intense iron dosing has been proposed in order to reduce ESA dosing but liberal intravenous iron therapy is also associated with complications, and its long-term safety has not yet been adequately investigated. For patients with CKD on dialysis, US medication labels recommend administering ESAs at doses sufficient to avoid transfusions, whereas European and Canadian labels recommend targeting haemoglobin levels of 100-120 g/l and 110-120 g/l, respectively. Treatment of anaemia to haemoglobin levels of 90-110 g/l in patients with CKD accomplishes what we want--a reduced need for transfusions and possible reductions in fatigue, while avoiding high doses of ESA or iron in order to achieve a specific haemoglobin goal.

Renal anaemia treatment in haemodialysis patients in the Central and Eastern European countries in everyday clinical practice follow-up

Background

Chronic kidney disease is almost always accompanied by anaemia. Erythropoietin-stimulating agents (ESA) can increase haemoglobin concentration and thus reduce the frequency of anaemia-related complications including the cardiovascular events.

Aim

The aim of the study was to collect prospective data on 12-month standard ESA therapy used in haemodialyzed patients in selected CEE countries as well as on cardiovascular complications, iron status and anaemia treatment.

Patients and methods

Fifty centres in 3 countries participated in the study. A group of 398 haemodialysed stable patients (M-231, F-167) aged 19–90 years (57.5 ± 14.7) on standard ESA therapy for chronic renal anaemia were recruited. Twelve-month prospective data on iron parameters, ESA therapy and cardiovascular events were collected. The use of iron, folic acid and blood transfusions were also assessed. Patient were divided into three groups according to ESA therapy start: group A—patients who received ESA after start of haemodialysis, group B—patients who received ESA within 3 months from the day of first haemodialysis and group C—patients who had received ESA more than 3 months before haemodialysis. Chi² test for qualitative data and Kruskall–Wallis test for quantitative data with p < 0.05 were used in statistical analysis.

Results

At prestudy period, the mean weekly dose of ESA in group C was statistically lower than in the remaining two groups (3,823 ± 3,169 vs. 5,276 ± 2,915 and 6,427 ± 3,441 units/week, p < 0.001), but during prospective phase of the study the doses did not differ among groups A, B and C. No major fluctuation of ESA administration schedule was observed during the study in the groups; however, at majority of visits, the mean frequency of ESA administration in group C was statistically higher than in groups A and B. At baseline visit, the haemoglobin concentration in group A patients (10.86 ± 1.34 g/dL) was slightly lower than in group B (11.26 ± 1.43 g/dL) and group C (10.98 ± 1.35 g/dL) (p = 0.025), but at subsequent visits these differences disappeared and mean haemoglobin concentration was stable around 11 g/dL. Ferritin concentration increased from 280 ± 241 at baseline to 506 ± 405 at month 12, and no important differences in the groups were observed. The other haematological parameters (haematocrit, iron concentration) remained stable during the entire study. The frequency of blood transfusion and total volume of blood in group C were lower than in groups A and B. During the prospective 12-month follow-up, 23 (5.8 %) of the patients died and 35 (8.8 %) were transplanted. No differences in death or transplantation rate were observed among groups A, B and C. The number of patients with adverse events, serious adverse events or drug-related adverse events in all groups was similar. In conclusion, ESA therapy increased haemoglobin concentration and no major differences in haematological parameters among the groups were observed during the entire study irrespective of early versus late start. Mortality, cardiovascular events or other adverse events were similar among the groups during the observation period; however, the limitation of the study is the sample size.

Myeloma kidney: improving clinical outcomes?

Renal impairment is a common complication of multiple myeloma, affecting 20% to 40% of new cases (depending on the definition). Most cases are mild and easily reversible, but it may manifest as severe acute renal injury requiring dialysis. Renal impairment is associated with a large tumor mass and consequently confers a poor prognosis. The prognosis of myeloma has improved with the introduction of novel agents and autologous stem cell transplantation. These improvements appear to apply equally to patients with renal impairment, although the risk of complication is usually higher in this group of patients. In addition to improved overall survival, there is some evidence that novel therapies have improved the renal prognosis. Treatment with high-dose dexamethasone and bortezomib can rapidly reduce light chain production and provide an opportunity for renal recovery. Although trials of plasma exchange (to remove the nephrotoxic light chain) have shown a disappointing lack of benefit, high cutoff dialysis removes larger quantities of light chain; therefore, trials are underway to investigate whether this can improve the renal prognosis independently of chemotherapy. Outcomes in patients with myeloma kidney do appear to be improving, but more trials are needed (some of which are in progress). There is cause for optimism for physicians and for patients suffering from this condition.

Fibroblast growth factor 23: friend or foe in uremia?

Uremia is a complex metabolic state marked by derangement of many signaling molecules and metabolic intermediates; of these, the massively increased levels of FGF23 are among the most striking. It has remained unclear whether FGF23 is directly implicated in the pathogenesis of chronic kidney disease (CKD) and its complications, a consequence of other dysregulated pathways, or perhaps an adaptive - and thus desirable - response. In this issue of the JCI, Shalhoub et al. describe the chronic effects of antibody-mediated FGF23 neutralization in a CKD mouse model, shedding new light on this complicated story and moving us one step closer to understanding the role of FGF23 in CKD.

Mortality in dialysis patients may not be associated with ESA dose: a 2-year prospective observational study

BACKGROUND

Anaemia of chronic kidney disease increases the risk of death and adverse events, but can be managed using erythropoiesis stimulating agents (ESAs). However, recent evidence suggests that targeting a higher haemoglobin concentration ([Hb]) increases mortality risk, and both higher [Hb] targets and ESA doses have been implicated. Nonetheless, a causative role has not been demonstrated, and this potential relationship requires further appraisal in such a complex patient group.

METHODS

The relationship between the haematopoietic response to ESAs and patient survival in 302 stable, prevalent dialysis patients was explored in a prospective, single-centre study. Clinical and laboratory parameters influencing mortality and ESA resistance were analysed. Patients were stratified into 5 groups, according to their [Hb] and ESA dosage, and were followed for 2 years.

RESULTS

Little difference in co-morbidities between groups was identified. 73 patients died and 36 were transplanted. Initial analysis suggested a direct relationship between mortality and ESA dosage. However, Cox proportional hazards multivariate analysis demonstrated mortality risk was associated only with age (adjusted HR per year: 1.061, 95% CI 1.031-1.092), dialysis duration (adjusted HR: 1.010, 95% CI 1.004-1.016), peripheral vascular disease (adjusted HR: 1.967, 95% CI 1.083-3.576) and CRP (adjusted HR: 1.024, 95% CI 1.011-1.039). Mortality was increased in patients poorly responsive to ESAs (55.5%).

CONCLUSION

ESA dose does not appear to contribute substantially to mortality risk in dialysis patients. Instead, age and co-morbidities appear to be the critical determinants. A poor response to ESAs is a marker of overall poor health status.

Impact of pharmacist-managed erythropoiesis-stimulating agents clinics for patients with non-dialysis-dependent CKD

BACKGROUND

Erythropoiesis-stimulating agents (ESAs) are associated with serious adverse events, and maintaining hemoglobin levels within a narrow range can be difficult. We examined the quality of ESA prescribing and monitoring in pharmacist-managed ESA clinics versus usual care in patients with non-dialysis-dependent chronic kidney disease (NDD-CKD).

STUDY DESIGN

Historical cohort.

SETTING & PARTICIPANTS

Outpatients receiving ESAs for NDD-CKD at 10 Veterans Affairs Medical Centers with both pharmacist-managed ESA clinics (n = 314) and physician-based care (ie, usual care; n = 91) and 6 sites with usual care only (n = 167) on January 1, 2009, were followed up for 6 months.

PREDICTOR

Type/site of care (ie, pharmacist-managed ESA clinic, usual care at ESA clinic site, usual-care site).

OUTCOMES

Primary outcomes were proportion of hemoglobin values in the target range of 10-12 g/dL, ESA dose, and frequency of hemoglobin monitoring. Factors associated with hemoglobin values out of target range were identified using multinomial logistic regression.

RESULTS

More hemoglobin values were in the target range in pharmacist-managed ESA clinics (71.1% vs 56.9% for usual-care sites; P < 0.001). The average 30-day dose of darbepoetin was 163 μg in pharmacist-managed ESA clinic patients versus 240 μg in usual-care site patients and 258 μg in usual-care patients at ESA clinic sites. For epoetin, corresponding average 30-day doses were 44,890 versus 47,141 and 57,436 IU. Veterans in pharmacist-managed ESA clinics had more hemoglobin measurements on average (5.8 vs 3.6 in usual-care sites and 3.8 in usual care at ESA clinic sites; P = 0.007). In the multinomial model, usual care was associated with hemoglobin levels out of target range, whereas heart failure and diabetes were associated with values in range.

LIMITATIONS

We could not assess whether different hemoglobin targets were used by usual-care providers.

CONCLUSIONS

Relative to usual care, pharmacist-managed clinics provided improved quality of ESA dosing and monitoring for patients with NDD-CKD.

Efficacy of hemopoietic-stimulating factors in patients undergoing chronic hemodialysis

Anemia has been linked to increased mortality and morbidity in renal hemodialysis patients. Other risk factors that contribute to an adverse outcome include the variability of hemoglobin (Hb) levels and the decreased response to erythropoiesis-stimulating factors (ESFs). In this study we evaluated the effectiveness of four different ESFs (epoetin-A, epoetin-B, darbepoetin, and CERA), assessed the variability of Hb levels, and compared ESF dosages which contributed to the achievement of Hb levels in each individual patient with renal failure undergoing chronic hemodialysis maintenance. In conclusion, the four ESFs administered are equally effective in the treatment of anemia in renal hemodialysis patients and they do not influence in a different manner the variability of Hb. The administration of darbepoetin-A and CERA might possibly cause more patients to overshoot the target level of Hb.

Renal anemia of inflammation: the name is self-explanatory

BACKGROUND

Anemia is inevitable as chronic kidney disease (CKD) advances. With the advent of erythropoietin-stimulating agents (ESAs), considerable improvement has been achieved in the management of anemia. However, some patients show a reduced response to ESAs.

METHODS

Many factors affect the response to ESA treatment. CKD is now considered as an inflammatory disorder and this understanding led to the recognition of the central role of inflammation in ESA resistance. Inflammation is related to untoward outcomes, including atherosclerosis and anemia, in the CKD population. Furthermore, recognition of deleterious effects of proinflammatory markers at different levels of erythropoiesis led to a change in the name of 'anemia of chronic disease' to anemia of inflammation.

RESULTS

The discovery of hepcidin as the major controller of iron metabolism in anemia of inflammation answered many questions regarding the interaction of erythropoietin, iron and bone marrow. Hepcidin production in the liver is driven by three major factors: inflammation, iron overload and anemia/hypoxia. Hepcidin levels are increased in patients with CKD due to the interaction of many factors; a comprehensive understanding of these pathways is thus critical in the effort to alleviate anemia of inflammation and ESA resistance.

CONCLUSION

In this review, we discussed the epidemiology, determinants and consequences of anemia of inflammation in CKD patients with special emphasis on the central role of hepcidin along with molecular pathways driving its production.

Do two intravenous iron sucrose preparations have the same efficacy?

Background. Intravenous (i.v.) iron sucrose similar (ISS) preparations are available but clinical comparisons with the originator iron sucrose (IS) are lacking.

Methods. The impact of switching from IS to ISS on anaemia and iron parameters was assessed in a sequential observational study comparing two periods of 27 weeks each in 75 stable haemodialysis (HD) patients receiving i.v. iron weekly and an i.v. erythropoiesis-stimulating agent (ESA) once every 2 weeks. Patients received IS in the first period (P1) and ISS in the second period (P2).

Results. Mean haemoglobin value was 11.78 ± 0.99 g/dL during P1 and 11.48 ± 0.98 g/dL during P2 (P = 0.01). Mean serum ferritin was similar for both treatment periods (P1, 534 ± 328 μg/L; P2, 495 ± 280 μg/L, P = 0.25) but mean TSAT during P1 (49.3 ± 10.9%) was significantly higher than during P2 (24.5 ± 9.4%, P <0.0001). The mean dose of i.v. iron per patient per week was 45.58 ± 32.55 mg in P1 and 61.36 ± 30.98 mg in P2 (+34.6%), while the mean ESA dose was 0.58 ± 0.52 and 0.66 ± 0.64 μg/kg/week, respectively (+13.8%). Total mean anaemia drug costs increased in P2 by 11.9% compared to P1.

Conclusions. The switch from the originator IS to an ISS preparation led to destabilization of a well-controlled population of HD patients and incurred an increase in total anaemia drug costs. Prospective comparative clinical studies are required to prove that ISS are as efficacious and safe as the originator i.v. IS.

Strategies and outcomes of cardiac surgery in Jehovah's Witnesses

BACKGROUND

Jehovah's Witnesses (JW) are a Christian faith, with an estimated 1.1 million members in the United States, well recognized for their refusal of blood and blood products. JW may not be considered for cardiac surgery due to perceived higher risks of morbidity and mortality. This study reviews our contemporary strategies and experience with JW undergoing routine and complex cardiac surgery.

METHODS

From November 2001 to April 2010, 40 JW were referred for cardiac surgery at a single quaternary referral institution. A retrospective analysis of demographic data, perioperative management, and clinical outcomes was examined. Published validated clinical risk calculator and model for prediction of transfusion were used to identify high-risk patients (risk of mortality >6% or probability of transfusion >0.80).

RESULTS

The mean age was 70 (± 9.5) years with 21 men and 19 women. Patients were classified as high risk (45%, n = 18) and low risk (55%, n = 22) with demographics and comorbidities listed in Table 2. Operative procedures included: isolated coronary artery bypass grafting (CABG) (n = 19), isolated valve replacement/repair (n = 7), valve/CABG (n = 7), reoperative valve replacement (n = 4), reoperative CABG (n = 2), valve/ascending aorta replacement (n = 1), and CABG/ascending aorta replacement (n = 1). All JW were evaluated by The Department of Bloodless Medicine to individually define acceptable blood management strategies. The mean preoperative hemoglobin was 14.1 g/dL (±1.6). Overall mortality was 5% (n = 2) all of which were in the high-risk group.

DISCUSSION

Using a multidisciplinary approach to blood management, JW can safely undergo routine and complex cardiac surgery with minimal morbidity and mortality.

Iron and vascular calcification. Is there a link?

Iron deficiency is frequently seen in patients with end-stage renal disease, particularly in those treated by dialysis, this is because of an impairment in gastrointestinal absorption and ongoing blood losses or alternatively, due to an impaired capacity to mobilize iron from its stores, called functional iron deficiency. Therefore, these patients may require intravenous iron to sustain adequate treatment with erythropoietin-stimulating agents. Aside from this, they are also prone to vascular calcification, which has been reported a major contributing factor in the development of cardiovascular disease and the increased mortality associated herewith. Several factors and mechanisms underlying the development of vascular calcification in chronic kidney diseased patients have been put forward during recent years. In view of the ability of iron to exert direct toxic effects and to induce oxidative stress on the one hand versus its essential role in various cellular processes on the other hand, the possible role of iron in the development of vascular calcification should be considered.

Drug-Induced Changes in Risk/Biomarkers and Their Relationship with Renal and Cardiovascular Long-Term Outcome in Patients with Diabetes

BACKGROUND

Optimal renal and cardiovascular risk management in diabetic patients includes optimal maintenance of blood pressure and control of glucose and lipids. Although the optimal control of these risk factors or “risk/biomarkers” has proven to be effective, it often is difficult to achieve. Consequently, the risk for renal and cardiovascular complications remains devastatingly high. Many risk/biomarkers have been discovered that accurately predict long-term renal and cardiovascular outcome. However, the aim of measuring risk/biomarkers may not be only to determine an individual's risk, but also to use the risk/biomarker level to guide therapy and thereby improve long-term clinical outcome.

CONTENT

This review describes the effects of various drugs on novel risk/biomarkers and the relationship between (drug induced) short-term changes in risk/biomarkers and long-term renal and cardiovascular outcome in patients with diabetes.

SUMMARY

In post hoc analyses of large trials, the short-term reductions in albuminuria, transforming growth factor-β, and N-terminal pro-B–type natriuretic peptide (NT-proBNP) induced by inhibitors of the renin-angiotensin-aldosterone system were associated with a decreased likelihood of long-term adverse renal and cardiovascular outcomes. However, the few studies that systematically investigated the utility of prospectively targeting novel risk/biomarkers such as hemoglobin or NT-proBNP failed to demonstrate long-term cardiovascular protection. The latter examples suggest that although a risk/biomarker may have superior prognostic ability, therapeutically changing such a risk/biomarker does not necessarily improve long-term outcome. Thus, to establish the clinical utility of other novel risk/biomarkers, clinical trials must be performed to prospectively examine the effects of therapeutically-induced changes in single or multiple risk/biomarkers on long-term risk management of patients with diabetes.