How the Target Hemoglobin of Renal Anemia Should Be

Clinical importance of distinguishing true anemia from dilutional pseudo-anemia: Consequences of a 3-year follow-up volume assessment in a heart failure patient

In chronic heart failure, dilutional anemia and hypervolemia may occur due to plasma volume expansion, the latter sometimes exacerbated by an increase in red cell volume. Diagnosis and a therapeutic strategy require determination of vascular volumes.

Ischemic Stroke During Daprodustat Therapy for Renal Anemia: A Report of Three Cases

Hypoxia-inducible factor prolyl hydroxylase (HIF-PH) inhibitors are increasingly used to treat renal anemia. Ischemic stroke is a rare severe adverse event of HIF-PH inhibitor therapy, and its clinical characteristics have not been described to date. We report three cases of ischemic stroke during treatment with daprodustat, a HIF-PH inhibitor, for anemia associated with non-dialysis-dependent chronic kidney disease (CKD). In two patients, the hemoglobin level exceeded the target hemoglobin level of 13 g/dL for renal anemia. Two patients developed ischemic stroke within two months after the daprodustat administration. None of the three patients experienced a recurrence of ischemic stroke after daprodustat discontinuation. Daprodustat therapy is a risk factor for ischemic stroke, particularly during excessive elevation of hemoglobin levels or the early phases of treatment. Daprodustat should be discontinued to mitigate the risk of ischemic stroke recurrence.

Associations of Air Pollution and Serum Biomarker Abnormalities in Individuals with Hemodialysis-Dependent Kidney Failure

BACKGROUND

Ambient particles with a median aerodynamic diameter of <2.5 µm (PM2.5) is a ubiquitous air pollutant with established adverse health consequences. While postulated to promote a systemic inflammatory response, limited studies have demonstrated changes in serum biomarkers related to PM2.5 exposure. We aim to examine associations between short-term PM2.5 exposure and commonly measured biomarkers known to be affected by inflammation among patients receiving maintenance in-center hemodialysis.

METHODS

We conducted a retrospective open cohort study from January 1, 2008, to December 31, 2014. Adult hemodialysis patients were identified from the United States Renal Data System and linked at the patient level to laboratory data from a large dialysis organization. Daily ambient PM2.5 was estimated on a 1-km grid and assigned to cohort patients based on the ZIP codes of dialysis clinics. Serum albumin, serum ferritin, transferrin saturation (TSAT), and serum hemoglobin were ascertained from the dialysis provider organization database. Mixed-effect models were used to assess the changes in biomarker levels associated with PM2.5 exposure.

RESULTS

The final cohort included 173,697 hemodialysis patients. Overall, the daily ZIP-level ambient PM2.5 averages were 8.4-8.5 µg/m3. A 10-µg/m3 increase in same-day ambient PM2.5 exposure was associated with higher relative risks of lower albumin (relative risk [RR], 1.01; 95% confidence interval [95% CI], 1.01 to 1.02) and lower hemoglobin (RR, 1.02; 95% CI, 1.01 to 1.03). Associations of same-day ambient PM2.5 exposure and higher ferritin and lower TSAT did not reach statistical significance.

CONCLUSIONS

Short-term PM2.5 exposure was associated with lower serum hemoglobin and albumin among patients receiving in-center hemodialysis. These findings lend support to the role of inflammation in PM2.5 exposure-outcome associations.

Additive Effect of Sarcopenia and Anemia on the 10-Year Risk of Cardiovascular Disease in Patients with Type 2 Diabetes

OBJECTIVE

To investigate the association between sarcopenia and anemia and the 10-year cardiovascular disease risk in diabetic patients.

METHODS

A cross-sectional study was conducted involving 4673 hospitalized patients (2271 men and 2402 women) with type 2 diabetes mellitus, with an average age of 60.66 ± 11.93 years, of whom 542 were followed up for a median follow-up period of 24 months. All participants underwent body composition measurements, and they were grouped by sex and presence of sarcopenia using the Framingham risk model to assess their 10-year cardiovascular risk. According to the changes in the cardiovascular risk during follow-up, the patients were divided into four groups: low-low, low-high, high-low, and high-high.

RESULTS

The prevalence of anemia was higher in the sarcopenia group than in the nonsarcopenia group (11.5% vs. 24.1% for men, P < 0.001; 13.9% vs. 19.7% for women, P < 0.05), and the difference remained significant after adjusting for confounders. Patients with sarcopenia and without anemia had a 46.2% increased risk of high 10-year cardiovascular disease (CVD) (odds ratio (OR) = 1.462, 95% confidence interval (CI) 1.085-1.972, P = 0.013), and the risk was twofold higher in patients with sarcopenia and anemia than in those without (OR = 3.283, 95% CI 2.038-5.289, P < 0.001). In follow-up studies, sarcopenia was associated with an increased risk of CVD at 10 years, and a reduction in appendicular skeletal muscle mass index independently predicted the increased risk of CVD.

CONCLUSION

Sarcopenia is associated with an increased risk of anemia, and the presence of both has an additive effect on the 10-year CVD risk in patients with type 2 diabetes. Loss of muscle mass can independently predict an increased CVD risk in diabetic patients.

Plasma erythropoietin level and heart failure in patients undergoing peritoneal dialysis: a cross-sectional study

Background

Renal anemia is the important complication in patients undergoing peritoneal dialysis (PD), and heart failure (HF) is the important complication in patients on dialysis. Decreasing endogenous erythropoietin (EPO) in patients with chronic kidney disease is a major cause of renal anemia. On the other hand, high levels of EPO have been associated with the prognosis of patients with chronic HF. The association between plasma EPO and HF in patients on PD remains unclear. This study was designed to test our hypothesis that the plasma EPO level in patients on PD was associated with the markers of HF.

Methods

We investigated 39 patients undergoing PD at our hospital. We measured plasma EPO before erythropoiesis-stimulating agent (ESA) administration at the regular outpatient visits and then at 2 weeks after the final dose of ESA was administered and investigated the clinical factors. We estimated the correlations between the plasma EPO and the other parameters, and constructed univariate and multivariate logistic regression models for the risk for HF to estimate the effectiveness of plasma EPO and other factors on HF treatment in patients undergoing PD.

Results

The plasma EPO concentration was positively correlated with the ESA dose and negatively correlated with serum ferrum, transferrin saturation, and body mass index and showed no correlation with other factors, such as the New York Heart Association (NYHA) classification and ferritin level. In univariate analysis, the factors significantly associated with HF risk were N-terminal pro-brain natriuretic peptide (NT-pro BNP), cardiothoracic ratio (CTR), serum creatinine (Cr), serum beta 2 microglobulin, dialysate dose, left ventricular mass index, left ventricular end-systolic diameter, left ventricular end-diastolic diameter, and weekly Kt/V. We performed a multivariate analysis with NT-pro BNP, Cr, and CTR, and all three factors were significant in the analysis.

Conclusion

The plasma EPO level in patients undergoing PD was positively correlated with the monthly ESA dose and was not significant as a marker of HF, as judged with the NYHA classification. Therefore, the plasma EPO level may not be a useful marker for HF in patients undergoing PD.

An evaluation of roxadustat for the treatment of anemia associated with chronic kidney disease

INTRODUCTION

Anemia is one of the major complications of chronic kidney disease (CKD). Erythropoiesis-stimulating agents (ESAs) have been the mainstay of renal anemia treatment. However, there are several safety drawbacks, and a safer and more effective alternative treatment has been sought.

AREAS COVERED

Hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) have been developed as a novel orally active therapeutic agent for renal anemia. HIF-PHIs stimulate endogenous EPO and optimize iron utilization. Roxadustat is a first-in-class HIF-PHI for the treatment of anemia in CKD patients approved in China, Japan, South Korea, and Chile. The authors herein evaluate the pharmacology of roxadustat and give their expert perspectives on its use.

EXPERT OPINION

Phase 3 clinical trials have demonstrated that roxadustat effectively increases and maintains hemoglobin (Hb) levels in both nondialysis-dependent and dialysis-dependent CKD patients. Roxadustat also improved iron metabolism and reduced intravenous (IV) iron requirements. However, pooled analyses of phase 3 studies have revealed frequent thromboembolic events in the roxadustat group, which might be attributed to rapid changes in Hb and inadequate iron supplementation. Roxadustat is an attractive alternative treatment especially for patients with ESA hyporesponsive due to impaired iron utilization, and so appropriate selection of target patients and its proper use are crucially important.

Severity of anaemia and association with all-cause mortality in patients with medically managed left-sided endocarditis

OBJECTIVE

To assess the prevalence and severity of anaemia in patients with left-sided infective endocarditis (IE) and association with mortality.

METHODS

In the Partial Oral versus Intravenous Antibiotic Treatment of Endocarditis trial, 400 patients with IE were randomised to conventional or partial oral antibiotic treatment after stabilisation of infection, showing non-inferiority. Haemoglobin (Hgb) levels were measured at randomisation. Primary outcomes were all-cause mortality after 6 months and 3 years. Patients who underwent valve surgery were excluded due to competing reasons for anaemia.

RESULTS

Out of 400 patients with IE, 248 (mean age 70.6 years (SD 11.1), 62 women (25.0%)) were medically managed; 37 (14.9%) patients had no anaemia, 139 (56.1%) had mild anaemia (Hgb <8.1 mmol/L in men and Hgb <7.5 mmol/L in women and Hgb ≥6.2 mmol/L) and 72 (29.0%) had moderate to severe anaemia (Hgb <6.2 mmol/L). Mortality rates in patients with no anaemia, mild anaemia and moderate to severe anaemia were 2.7%, 3.6% and 15.3% at 6-month follow-up and 13.5%, 20.1% and 34.7% at 3-year follow-up, respectively. Moderate to severe anaemia was associated with higher mortality after 6 months (HR 4.81, 95% CI 1.78 to 13.0, p=0.002) and after 3 years (HR 2.14, 95% CI 1.27 to 3.60, p=0.004) and remained significant after multivariable adjustment.

CONCLUSION

Moderate to severe anaemia was present in 29% of patients with medically treated IE after stabilisation of infection and was independently associated with higher mortality within the following 3 years. Further investigations are warranted to determine whether intensified treatment of anaemia in patients with IE might improve outcome.

Current Status of Renal Anemia Pharmacotherapy-What Can We Offer Today

Chronic kidney disease (CKD) is one of the fastest-growing major causes of death internationally. Better treatment of CKD and its complications is crucial to reverse this negative trend. Anemia is a frequent complication of CKD and is associated with unfavorable clinical outcomes. It is a devastating complication of progressive kidney disease, that negatively affects also the quality of life. The prevalence of anemia increases in parallel with CKD progression. The aim of this review is to summarize the current knowledge on therapy of renal anemia. Iron therapy, blood transfusions, and erythropoietin stimulating agents are still the mainstay of renal anemia treatment. There are several novel agents on the horizon that might provide therapeutic opportunities in CKD. The potential therapeutic options target the hepcidin–ferroportin axis, which is the master regulator of iron homeostasis, and the BMP-SMAD pathway, which regulates hepcidin expression in the liver. An inhibition of prolyl hydroxylase is a new therapeutic option becoming available for the treatment of anemia in CKD patients. This new class of drugs stimulates the synthesis of endogenous erythropoietin and increases iron availability. We also summarized the effects of prolyl hydroxylase inhibitors on iron parameters, including hepcidin, as their action on the hematological parameters. They could be of particular interest in the out-patient population with CKD and patients with ESA hyporesponsiveness. However, current knowledge is limited and still awaits clinical validation. One should be aware of the potential risks and benefits of novel, sophisticated therapies.

Roxadustat treatment for anemia in peritoneal dialysis patients: A randomized controlled trial

BACKGROUND/PURPOSE

Roxadustat, a first-in-class hypoxia-inducible factor prolyl hydroxylase inhibitor, promotes erythropoiesis and regulates iron metabolism. This study investigated the efficacy and safety of roxadustat in Chinese patients with anemia on peritoneal dialysis (PD).

METHODS

One hundred and twenty-nine patients were randomized and treated with roxadustat (n = 86) or erythropoiesis-stimulating agents (ESAs) (n = 43) for 24 weeks. The primary end points were the mean hemoglobin (Hb) level at week 24, the change in average Hb levels from baseline to week 24, and the cumulative response rate throughout the treatment period. The secondary end points included changes in hepcidin and iron indices and serum lipid levels. Subgroup analysis examined the effect of inflammatory status on the efficacy of Hb. Safety was assessed as the occurrence of emergent adverse events after treatment.

RESULTS

The mean average Hb levels at week 24 and average change in Hb levels from baseline to week 24 were 11.5 g/dL and 2.5 g/dL in the roxadustat group and 11.2 g/dL and 2.2 g/dL in the ESAs group, respectively. The cumulative response rate was 96% in the roxadustat group and 92% in the ESAs group at week 24. Roxadustat decreased hepcidin levels and increased total iron-binding capacity. The decreases in total cholesterol and low-density lipoprotein cholesterol were greater with roxadustat than with ESAs. Roxadustat-induced Hb increases were independent of baseline C-reactive protein levels. Common adverse events included hyperkalemia, hypertension, and insomnia.

CONCLUSION

Roxadustat effectively corrected and maintained target Hb levels in Chinese PD patients. This trial was registered in the Chinese Clinical Trial Register (ChiCTR2000035054).

HIF-α Prolyl Hydroxylase Inhibitors and Their Implications for Biomedicine: A Comprehensive Review

Oxygen is essential for the maintenance of the body. Living organisms have evolved systems to secure an oxygen environment to be proper. Hypoxia-inducible factor (HIF) plays an essential role in this process; it is a transcription factor that mediates erythropoietin (EPO) induction at the transcriptional level under hypoxic environment. After successful cDNA cloning in 1995, a line of studies were conducted for elucidating the molecular mechanism of HIF activation in response to hypoxia. In 2001, cDNA cloning of dioxygenases acting on prolines and asparagine residues, which play essential roles in this process, was reported. HIF-prolyl hydroxylases (PHs) are molecules that constitute the core molecular mechanism of detecting a decrease in the partial pressure of oxygen, or hypoxia, in the cells; they can be called oxygen sensors. In this review, I discuss the process of molecular cloning of HIF and HIF-PH, which explains hypoxia-induced EPO expression; the development of HIF-PH inhibitors that artificially or exogenously activate HIF by inhibiting HIF-PH; and the significance and implications of medical intervention using HIF-PH inhibitors.

Bilateral Optic Atrophy in a Young Patient With Chronic Anaemia Secondary to End-Stage Renal Disease

End-stage renal disease (ESRD) is associated with a number of serious complications, including increased cardiovascular disease, anaemia and metabolic bone disease. Optic atrophy secondary to chronic anaemia in ESRD is rare. We report a case of bilateral optic atrophy in a young patient with chronic anaemia secondary to ESRD. A 23-year-old lady with ESRD, presented with progressive blurring of vision in her left eye for a period of six months. Visual acuity in the left eye was counting finger and the right eye was 6/6. Left optic nerve functions were significantly reduced. Bilateral anterior segments and intraocular pressure were normal. Funduscopy showed bilateral pale disc with arteriolar attenuation. The infective, autoimmune and demyelinating screening were negative. Serial full blood count indicated low haemoglobin and haematocrit value. The full blood picture revealed normocytic normochromic anaemia. Neuroimaging was normal. The patient was diagnosed as having bilateral optic atrophy secondary to chronic anaemia due to ESRD. Chronic anaemia is a potential cause of optic atrophy in a young patient with chronic disease. Management of anaemia in such cases is crucial to prevent irreversible complications including optic atrophy and blindness.

Association of less-contrast media with clinical factors in elective percutaneous coronary intervention

Since the amount of contrast media during percutaneous coronary intervention (PCI) is closely related to the exacerbation of renal function, it should be important to reduce the dose of contrast media during PCI. The purpose of this retrospective study was to evaluate the association of less-contrast media with clinical factors in elective PCI. A total of 709 patients were divided into the less-contrast media group (n = 142) and the conventional-contrast media group (n = 567) according to the quintile of total contrast volume. Univariate and multivariate logistic regression analyses were performed to find associations between the clinical variables and the less-contrast media group. The intravascular ultrasound (IVUS) use rate in the study population was considerably high (94.9%). In multivariable logistic regression analysis, an eGFR < 30 mL/min/1.73 m² without hemodialysis was significantly associated with the less-contrast media group [odds ratio (OR) 43.73, 95% confidence interval (CI) 14.05-136.09, P < 0.001]. Left main-left anterior descending artery lesion (OR 0.28, 95% CI 0.17-0.48, P < 0.001), bifurcation lesion (OR 0.39, 95% CI 0.16-0.92, P = 0.03), chronic total occlusion (OR 0.22, 95% CI 0.06-0.90, P = 0.03) were inversely associated with the less-contrast media group. In conclusion, complex lesion characteristics were inversely associated with the less-contrast media in elective PCI. Since operators could access patients' renal function before elective procedure, an eGFR < 30 mL/min/1.73 m² was most significantly associated with the less-contrast media. Our results suggest the possibility that the amount of contrast media is controllable in current PCI under IVUS-guidance.

Safety and effectiveness of long-term use of darbepoetin alfa in non-dialysis patients with chronic kidney disease: a post-marketing surveillance study in Japan

Background

This post-marketing surveillance (PMS) study evaluated the safety and effectiveness of long-term darbepoetin alfa (darbepoetin) for the treatment of renal anemia in Japanese non-dialysis chronic kidney disease patients.

Methods

Patients were treated with darbepoetin and followed up for 3 years. Adverse events (AEs), adverse drug reactions (ADRs), hemoglobin (Hb) levels, and renal function were assessed. Patients were stratified by Hb level at the time of occurrence of cardiovascular-related AEs. Statistical analyses were performed to explore factors affecting the occurrence of AEs, cardiovascular-related AEs, and composite renal endpoints.

Results

In the safety analysis set (5547 patients), AEs and ADRs occurred in 44.4 and 7.1% of patients, respectively. Cardiovascular-related AEs were observed in 12.6% of the overall population. The proportion of patients who presented cardiovascular-related AEs was lower among those with a higher Hb level at the time of occurrence. In the effectiveness analysis set (5024 patients), mean Hb levels remained between 10.0 and 10.6 g/dL (Weeks 4–156). Three months after darbepoetin administration, patients with Hb ≥ 11 g/dL presented fewer composite renal endpoints than those with Hb < 11 g/dL (p = 0.0013), and the cumulative proportion of renal survival was higher in those with Hb ≥ 11 g/dL vs. Hb < 11 g/dL (p < 0.0001).

Conclusions

This PMS study showed the safety and effectiveness of long-term use of darbepoetin in a large number of patients. Patients with Hb ≥ 11 g/dL presented fewer composite renal endpoints than those with Hb < 11 g/dL, without an increase in the incidence of cardiovascular-related AEs.

Electronic supplementary material

The online version of this article (10.1007/s10157-018-1632-9) contains supplementary material, which is available to authorized users.

Normal and pathological erythropoiesis in adults: from gene regulation to targeted treatment concepts

Pathological erythropoiesis with consequent anemia is a leading cause of symptomatic morbidity in internal medicine. The etiologies of anemia are complex and include reactive as well as neoplastic conditions. Clonal expansion of erythroid cells in the bone marrow may result in peripheral erythrocytosis and polycythemia but can also result in anemia when clonal cells are dysplastic and have a maturation arrest that leads to apoptosis and hinders migration, a constellation typically seen in the myelodysplastic syndromes. Rarely, clonal expansion of immature erythroid blasts results in a clinical picture resembling erythroid leukemia. Although several mechanisms underlying normal and abnormal erythropoiesis and the pathogenesis of related disorders have been deciphered in recent years, little is known about specific markers and targets through which prognosis and therapy could be improved in anemic or polycythemic patients. In order to discuss new markers, targets and novel therapeutic approaches in erythroid disorders and the related pathologies, a workshop was organized in Vienna in April 2017. The outcomes of this workshop are summarized in this review, which includes a discussion of new diagnostic and prognostic markers, the updated WHO classification, and an overview of new drugs used to stimulate or to interfere with erythropoiesis in various neoplastic and reactive conditions. The use and usefulness of established and novel erythropoiesis-stimulating agents for various indications, including myelodysplastic syndromes and other neoplasms, are also discussed.

Oral Ferric Citrate Hydrate Associated With Less Oxidative Stress Than Intravenous Saccharated Ferric Oxide

Introduction

A recent study suggested that orally dosed ferric citrate hydrate (FC) corrects renal anemia in patients on hemodialysis (HD), suggesting biological differences in effects of iron supplementation using different routes of administration. To address this issue, the present study compared oral FC with i.v. saccharated ferric oxide (FO) in stable HD patients.

Methods

Participants comprised 6 patients administered 3 consecutive protocols in the first HD session of the week in a fasting state: nothing given, as control (C); oral load of FC (480 mg iron), and 5 minutes of i.v. FO (40 mg iron). Iron dynamics in the body and biological impact on redox-inflammation status during the study (6 hours) were examined.

Results

Significant increases in serum iron and transferrin saturation were seen with both FC and FO. Regarding total iron-binding capacity as the sum of serum iron and unsaturated iron-binding capacity, no changes were found in FC, whereas significant increases were seen in FO (appearance of non–transferrin-binding iron [NTBI]), despite the lower serum iron levels in FO. Compared with C, increases were seen in serum myeloperoxidase (oxidative marker) with accompanying significant decreases in thioredoxin (antioxidant) in FO, whereas no changes were found in FC.

Conclusion

Oral FC differs from i.v. FO in areas such as less NTBI generation and less induction of oxidative stress. The result indicates potential clinical benefits of oral FC in terms of iron supplementation for renal anemia in HD patients.

New insights into molecular mechanisms of epigenetic regulation in kidney disease

The number of patients with kidney failure has increased in recent years. Different factors contribute to the progression of chronic kidney disease, including glomerular sclerosis, atherosclerosis of the renal arteries and tubulointerstitial fibrosis. Tubulointerstitial injury is induced by hypoxia and other inflammatory signals, leading to fibroblast activation. Technological advances using high-throughput sequencing has enabled the determination of the expression profile of almost all genes, revealing that gene expression is intricately regulated by DNA methylation, histone modification, changes in chromosome conformation, long non-coding RNAs and microRNAs. These epigenetic modifications are stored as cellular epigenetic memory. Epigenetic memory leads to adult-onset disease or ageing in the long term and may possibly play an important role in the kidney disease process. Herein we emphasize the importance of clarifying the molecular mechanisms underlying epigenetic modifications because this may lead to the development of new therapeutic targets in kidney disease.

End-stage renal disease versus death in a Portuguese cohort of elderly patients: an approach using competing event analysis

Chronic kidney disease (CKD) is higher in elderly, but mortality outweighs the risk of end-stage renal disease (ESRD). Our aim was to identify prognostic markers for ESRD or death in elderly CKD, within a competing-risk analysis. This is a longitudinal study of consecutive newly referred patients with CKD ages 65 years, followed until the time of the first event (ESRD or death), using a competing-risk analysis. A modified Charlson Comorbidity Index (mCCI) was subdivided into subgroups (0-2, 3-4, ≥5). Patients were followed for hospitalizations that occurred prior to the outcomes. Among 416 patients, age 76±8 years, 52% male, median estimated glomerular filtration rate of 32 mL/min per 1.73 m², 50% had diabetes, and 67% cardiovascular disease. Over a median follow-up of 3.6 years, 36 patients progressed to ESRD (8.7%) and 103 died (24.8%). Older age (subdistribution HR (sHR)=1. 06; p<0.001), creatinine≥1.6 mg/dL (sHR=2.03, p=0.004), hemoglobin <11 g/dL (sHR=1.91, p=0.003), mCCI score≥5 (sHR=3.01, p<0.001) and having one or more hospitalizations (sHR=1.73, p<0.001) were associated with death before ESRD. The independent predictors for ESRD with competing risk of death were: lower age (sHR=0.94; p=0.009), creatinine≥1.6 mg/dL (sHR=3.26, p=0.006), hemoglobin <11 g/dL (sHR=2.15, p=0.027), peripheral vascular disease (sHR=3.45, p=0.001) and having one or more hospitalizations (sHR=1.56, p=0.031). Elderly referred patients with CKD are near threefold more likely to die than progress to ESRD. A competing-risk framework based on available clinical and laboratory data may discriminate between those outcomes and could be used as a decision-making tool.