Associations between changes in hemoglobin and administered erythropoiesis-stimulating agent and survival in hemodialysis patients

Effects of Individualized Anemia Therapy on Hemoglobin Stability: A Randomized Controlled Pilot Trial in Patients on Hemodialysis

Key Points

Background

Anemia is common among patients on hemodialysis. Maintaining stable hemoglobin levels within predefined target levels can be challenging, particularly in patients with frequent hemoglobin fluctuations both above and below the desired targets. We conducted a multicenter, randomized controlled trial comparing our anemia therapy assistance software against a standard population-based anemia treatment protocol. We hypothesized that personalized dosing of erythropoiesis-stimulating agents (ESAs) improves hemoglobin target attainment.

Methods

Ninety-six patients undergoing hemodialysis and receiving methoxy polyethylene glycol-epoetin beta were randomized 1:1 to the intervention group (personalized ESA dose recommendations computed by the software) or the standard-of-care group for 26 weeks. The therapy assistance software combined a physiology-based mathematical model and a model predictive controller designed to stabilize hemoglobin levels within a tight target range (10–11 g/dl). The primary outcome measure was the percentage of hemoglobin measurements within the target. Secondary outcome measures included measures of hemoglobin variability and ESA utilization.

Results

The intervention group showed an improved median percentage of hemoglobin measurements within target at 47% (interquartile range, 39–58), with a 10% point median difference between the two groups (95% confidence interval, 3 to 16; P = 0.008). The odds ratio of being within the hemoglobin target in the standard-of-care group compared with the group receiving the personalized ESA recommendations was 0.68 (95% confidence interval, 0.51 to 0.92). The variability of hemoglobin levels decreased in the intervention group, with the percentage of patients experiencing fluctuating hemoglobin levels being 45% versus 82% in the standard-of-care group. ESA usage was reduced by approximately 25% in the intervention group.

Conclusions

Our results demonstrated an improved hemoglobin target attainment and variability by using personalized ESA recommendations using the physiology-based anemia therapy assistance software.

Clinical Trial registration number:

NCT04360902.

Iron Indices Mediate but Not Modify Association of Parathyroid Hormone with Erythropoietin Resistance in Hemodialysis Patients

INTRODUCTION

Disordered iron balance and abnormal parathyroid hormone (PTH) concentrations, both prevalent in hemodialysis patients, are risk factors of erythropoietin (EPO) resistance. Few studies have evaluated the correlation between iron indices and PTH and the potential role of iron markers on the association of PTH with EPO resistance in hemodialysis population.

METHODS

In this cross-sectional study of 71 maintenance hemodialysis patients, iron indices including hepcidin, ferritin, reticulocyte hemoglobin content (CHr), and transferrin saturation (TSAT) were examined. EPO responsiveness was measured as EPO resistance index (ERI). Lowess regression curves were performed to explore the correlations of iron indices, PTH, and ERI. The association between PTH and ERI was modeled using linear regressions. Potential role of iron indices on this association was examined using stratified analyses and mediation analyses.

RESULTS

The average ERI value was 10.3 ± 5.3 IU w-1 kg-1 (g/dL) -1. ERI was correlated to PTH, hepcidin, CHr, and TSAT (all p < 0.05). Hepcidin and PTH were closely correlated with each other (r = 0.28, p = 0.020). Analysis by PTH categories yielded a total association effect of 2.53 (95% CI: 0.27-4.85, p = 0.027) for high PTH subgroup versus the reference low subgroup. No clinically significant interaction between iron indexes and PTH was identified. Hepcidin appeared to mediate about one-third of the total association between PTH and ERI in hemodialysis population (33.6%, p = 0.025).

CONCLUSION

Iron indices and PTH levels were related to ERI values. Hepcidin appeared to be closely correlated to PTH and partly mediate the association between PTH and ERI in hemodialysis population.

Short versus long-acting erythropoiesis-stimulating agents for anemia management in Egyptian hemodialysis patients

BACKGROUND

Chronic kidney disease (CKD) often results in renal anemia, impacting the well-being of patients and causing various negative consequences. Erythropoiesis-stimulating agents (ESAs) offer promising solutions for managing anemia in CKD. This study aimed to evaluate and compare the effectiveness, safety profile, and cost-effectiveness of short-acting (Eprex®) and long-acting (Aranesp®) ESAs.

METHOD

This comparative prospective cohort cost-effectiveness study was carried out over 6 months among adult Egyptian hemodialysis patients of either gender. Participants were categorized into two groups based on the type of ESA administered: the Eprex group, receiving epoetin alfa, and the Aranesp group, receiving darbepoetin alfa. These two treatment groups' efficacy, safety, and cost were analyzed and compared.

RESULTS

Of 127 hemodialysis patients, 60 (47.2%) received Eprex, while 67 (52.8%) were treated with Aranesp. Target hemoglobin (Hb) was achieved by 50.6% of patients in the Eprex group versus 63.4% in the Aranesp group, with a significant difference (P < 0.001). Both treatment groups exhibited a similar safety profile, while Aranesp® was considered the cost-saving protocol.

CONCLUSION

In hemodialysis Egyptian patients, Aranesp with extended dosing intervals proved to be more effective in achieving target Hb with comparable adverse effect profiles, a substantial cost-saving strategy, and offered time-saving advantages for medical staff workload compared to Eprex.

TRIAL REGISTRATION

The Clinicaltrial.gov registration ID is NCT05699109 (26/01/2023).

Effect of vitamin D supplementation on management of anemia in hemodialysis patients with vitamin D deficiency: A double-blind, randomized, controlled trial

INTRODUCTION

Anemia and vitamin D deficiency are common problems among hemodialysis (HD) patients. This study aimed to assess the impact of correction of vitamin D deficiency with vitamin D supplementation on the improvement of anemia in patients with end-stage renal disease (ESRD) on maintenance HD.

METHODS

This double-blind, randomized, controlled study included 100 anemic HD patients with vitamin D deficiency who were randomly divided using the closed envelop method into two groups (1:1). The first group received vitamin D (50,000 IU) monthly for 6 months, and the other group received a placebo for the same period. 25-Hydroxyvitamin D (25(OH)D) levels were measured for both groups at the beginning of the study and after 6 months at the end of the study. Hemoglobin (Hb) concentrations were recorded monthly.

FINDINGS

Vitamin D supplementation during the period of the study increased 25(OH)D levels in the vitamin D group more than the placebo group (p > 0.001). Serum ferritin, serum iron, and transferrin saturation did not differ significantly between both groups during the period of the study. Hb concentration in the vitamin D group increased more than that in the other group over the period of the study, and there was a statistically significant difference between the two groups in all durations of follow-up. Erythropoietin (EPO) dosage requirements were found to be lower in the vitamin D group than in the placebo group, and this was statistically significant (p > 0.001).

DISCUSSION

Vitamin D supplementation in anemic ESRD patients on HD with vitamin D deficiency or insufficiency is safe and effective in improving anemia and decreasing EPO dosage.

Role of Erythropoiesis-Stimulating Agents in Cardiovascular Protection in CKD Patients: Reappraisal of Their Impact and Mechanisms

Erythropoiesis-stimulating agents (ESAs) have markedly reduced the need for blood transfusion for renal anemia and are included in standard therapies for patients with chronic kidney disease (CKD). Various protective effects of ESAs on the cardiovascular system have been discovered through basic research, and the effects have received much attention because the rates of cardiovascular events and mortality are high in CKD patients. However, randomized clinical trials did not provide strong evidence that ESAs exert cardioprotection in humans, including CKD patients. It is difficult to assess the cardioprotective effects of ESAs in CKD patients through the clinical data that has been reported to date because the relationship between hemoglobin level rather than ESA dose and cardiovascular event rates was examined in most studies. Interestingly, recent studies using a rat model of CKD showed that the infarct size-limiting effect of an ESA was lost when its dose was increased to a level that normalized blood hemoglobin levels, suggesting that the optimal dose of an ESA for myocardial protection is less than the dose required to normalize hemoglobin levels. Furthermore, animal models of traditional coronary risk factors or comorbidities were resistant to the cardioprotective effects of ESAs because of interruptions in signal-mediated mechanisms downstream of erythropoietin receptors. In this review, we briefly discuss basic and clinical data on the impact of anemia on coronary and systemic circulation, the effects of CKD on the cardiovascular system, and the multiple pharmacological actions of ESAs to examine whether the ESAs that are prescribed for renal anemia exert any cardioprotection in patients with CKD.

Erythropoiesis-stimulating agents and cardiovascular mortality: A systematic review and meta-analysis of 17 studies and 372,156 hemodialysis patients

Introduction

Prior studies on the association between erythropoiesis-stimulating agents (ESAs) and cardiovascular mortality in hemodialysis patients have yielded conflicting findings. We aimed to clarify this relationship through a systematic review and meta-analysis of current evidence.

Methods

We comprehensively searched major databases for observational and interventional studies on ESA use and cardiovascular mortality in hemodialysis patients published from 1980 to September 2023. Pooled risk ratios (RR) with 95 % confidence intervals (CI) were calculated using random-effects models. Sources of heterogeneity were explored through subgroup analyses and meta-regression. The study data were analyzed using Stata 15 software.

Findings

Upon conducting the initial search, we extracted 792 articles and, after screening and considering the research criteria, 17 studies with 372,156 participants were included in the meta-analysis. Overall, ESA use was associated with a 27 % increased risk of cardiovascular mortality (RR 1.27, 95 % CI: 1.15-1.40, p < 0.001). This risk varied by geographical location, with RRs of 1.27 (95 % CI: 1.14-1.41; p-value≤0.001) for America, 1.33 (95 % CI: 1.12-1.58; p-value = 0.001) for Asia, and 1.23 (95 % CI: 1.02-1.49; p-value = 0.028) for Europe. Importantly, a gender disparity was revealed, with studies involving a higher proportion of males showing greater risks (RR 1.51, 95 % CI: 1.25-1.83, p < 0.001) than female-predominant studies (RR 1.08, 95 % CI: 0.86-1.36, p < 0.001).

Conclusion

Our meta-analysis indicates ESA use is associated with heightened cardiovascular mortality in hemodialysis patients, especially in males. These findings have implications for optimizing dosing strategies while balancing efficacy and safety. Further research is warranted, particularly randomized controlled trials, to establish definitive ESA dosing guidelines.

Investigating the relationship between erythropoiesis-stimulating agents and mortality in hemodialysis patients: A systematic review and meta-analysis

BACKGROUND

In recent years, various studies have been conducted to investigate the relationship between erythropoiesis-stimulating agents (ESAs) and mortality in hemodialysis patients, who showed contradictory results. Therefore, this study aimed to investigate the relationship between ESAs and mortality in hemodialysis patients.

METHODS

The current study is a systematic review and meta-analysis based on observational and interventional studies published in the Web of Science, Cochrane Library, Science Direct, PubMed, Scopus, and Google Scholar databases between 1980 and the end of 2022. Jadad scale checklist and Newcastle Ottawa scale were used to evaluate the quality of articles. The study data were analyzed using Stata 15 software.

RESULTS

In the initial search, 3933 articles were extracted, and by screening and considering the research criteria, 68 studies were finally included in the meta-analysis. According to the meta-analysis results, the risk ratio (RR) of overall mortality in hemodialysis patients receiving ESAs was equal to 1.19 (95% CI: 1.16-1.23, P ≤ 0.001). The RR of mortality in patients aged 60 years and under was equal to 1.33 (1.15-1.55, P ≤ 0.001), in the age group over 60 years was equal to 1.13 (1.10-1.16, P ≤ 0.001), in randomized clinical trial studies was equal to 1.06 (0.80-1.40, P = 0.701), in cohort studies was equal to 1.20 (1.16-1.25, P ≤ 0.001), in American countries was equal to 1.19 (1.10-1.29, P ≤ 0.001), in Asian countries was equal to 1.15 (1.10-1.19, P ≤ 0.001), and in European countries was equal to 1.18 (1.05-1.34, P = 0.007).

CONCLUSION

The results of the study show that receiving ESAs is associated with a 19% increase in the risk of overall mortality in hemodialysis patients.

Comparative Effectiveness of Dynamic Treatment Strategies for Medication Use and Dosage: Emulating a Target Trial Using Observational Data

BACKGROUND

Availability of detailed data from electronic health records (EHRs) has increased the potential to examine the comparative effectiveness of dynamic treatment strategies using observational data. Inverse probability (IP) weighting of dynamic marginal structural models can control for time-varying confounders. However, IP weights for continuous treatments may be sensitive to model choice.

METHODS

We describe a target trial comparing strategies for treating anemia with darbepoetin in hemodialysis patients using EHR data from the UK Renal Registry 2004 to 2016. Patients received a specified dose (microgram/week) or did not receive darbepoetin. We compared 4 methods for modeling time-varying treatment: (A) logistic regression for zero dose, standard linear regression for log dose; (B) logistic regression for zero dose, heteroscedastic linear regression for log dose; (C) logistic regression for zero dose, heteroscedastic linear regression for log dose, multinomial regression for patients who recently received very low or high doses; and (D) ordinal logistic regression.

RESULTS

For this dataset, method (C) was the only approach that provided a robust estimate of the mortality hazard ratio (HR), with less-extreme weights in a fully weighted analysis and no substantial change of the HR point estimate after weight truncation. After truncating IP weights at the 95th percentile, estimates were similar across the methods.

CONCLUSIONS

EHR data can be used to emulate target trials estimating the comparative effectiveness of dynamic strategies adjusting treatment to evolving patient characteristics. However, model checking, monitoring of large weights, and adaptation of model strategies to account for these is essential if an aspect of treatment is continuous.

Continuous Erythropoietin Receptor Activator for the Treatment of Chronic Dialysis Patients with Renal Anemia in Daily Clinical Practice in Poland: A Non-Interventional, Multi-Center, Pragmatic NAVIGO Trial

BACKGROUND

Renal anemia is one of the most common complications of chronic kidney disease (CKD). This real-life study assessed the effectiveness of methoxy polyethylene glycol-epoetin beta, a continuous erythropoietin receptor activator (C.E.R.A.), for the treatment of CKD-associated anemia in patients receiving dialysis in daily clinical practice.

METHODS

247 patients receiving chronic intermitted dialysis in 26 centers in Poland with CKD-associated symptomatic anemia, ESA-naïve, and with balanced iron stores in the investigators' opinion were enrolled this real-life study. Over 12 months, the following data were collected: hemoglobin (Hb) concentration and dosage, route of administration and dosing scheme of C.E.R.A., dialysis adequacy, adverse events, iron therapy, and blood transfusions.

RESULTS

During the treatment, a Hb concentration of ≥10 g/dL was noted in 90.9% of hemodialysis patients (n = 224) and 96.0% of peritoneal dialysis patients (n = 23). At baseline, 7.8% of patients had a Hb concentration of 10-12 g/dL, which increased to 63.3% after 12 months. The median time when Hb concentration was maintained within 10-12 g/dL was 115.2 (interquartile range 49.1-188.7) days. A Hb concentration ≥12 g/dL was observed after 7 months of treatment in a maximum of 24.1% of hemodialysis patients, and 31.8% of peritoneal dialysis patients. The median time elapsed between the start of treatment and the first Hb concentration >10 g/dL was 42.0 (21.0-78.2) days. C.E.R.A. was well tolerated.

CONCLUSIONS

C.E.R.A. corrects CKD-associated anemia in dialysis patients, and maintains Hb levels within the recommended target range. The study also confirmed the acceptable safety profile of the drug.

Infectious Risk and Variability of Hemoglobin Level in Patients Undergoing Hemodialysis

Introduction

In the management of anemia in chronic kidney disease, hemoglobin levels often fall below or exceed target ranges. Past retrospective cohort studies of patients undergoing hemodialysis with conventional erythropoiesis stimulating agents (ESAs) found that hemoglobin level fluctuations predicted mortality and cardiovascular adverse events; long-acting agents were thereafter widely available. An updated validation by a prospective cohort study was needed.

Methods

Using Cox regression models, we evaluated associations between hemoglobin variability and all-cause death, hospitalization, and cardiovascular, thrombotic, or infectious adverse event outcomes in 3063 hemodialysis patients' data from the Japanese Dialysis Outcomes and Practice Patterns Study (J-DOPPS) from 2012 to 2018.

Results

During a median follow-up time of 2.5 years, all-cause mortality was lowest in the first quartile and tended to be higher in groups with greater hemoglobin variability (hazard ratio [HR]: 95% confidence interval for the fourth quartile of an absolute value of hemoglobin variability: 1.44 [0.99-2.08], P for trend = 0.056). Infectious event incidence in these patients was also lower in the first quartile than for the other quartiles (P for trend < 0.01). The association was more pronounced in patients with lower serum ferritin levels or iron supplementation. Cardiovascular and thrombotic event incidence was not associated with hemoglobin variability.

Conclusions

Maintenance hemodialysis patients on ESA treatment with higher hemoglobin variability are at higher risk for all-cause mortality and particularly infectious events.

A single approach to targeting transferrin receptor 2 corrects iron and erythropoietic defects in murine models of anemia of inflammation and chronic kidney disease

Anemia is a common complication of systemic inflammation. Proinflammatory cytokines both decrease erythroblast sensitivity to erythropoietin (EPO) and increase the levels of the hepatic hormone hepcidin, sequestering iron in stores and causing functional iron deficiency. Anemia of chronic kidney disease (CKD) is a peculiar form of anemia of inflammation, characterized by impaired EPO production paralleling progressive kidney damage. Traditional therapy based on increased EPO (often in combination with iron) may have off-target effects due to EPO interaction with its non-erythroid receptors. Transferrin Receptor 2 (Tfr2) is a mediator of the iron-erythropoiesis crosstalk. Its deletion in the liver hampers hepcidin production, increasing iron absorption, whereas its deletion in the hematopoietic compartment increases erythroid EPO sensitivity and red blood cell production. Here, we show that selective hematopoietic Tfr2 deletion ameliorates anemia in mice with sterile inflammation in the presence of normal kidney function, promoting EPO responsiveness and erythropoiesis without increasing serum EPO levels. In mice with CKD, characterized by absolute rather than functional iron deficiency, Tfr2 hematopoietic deletion had a similar effect on erythropoiesis but anemia improvement was transient because of limited iron availability. Also, increasing iron levels by downregulating only hepatic Tfr2 had a minor effect on anemia. However, simultaneous deletion of hematopoietic and hepatic Tfr2, stimulating erythropoiesis and increased iron supply, was sufficient to ameliorate anemia for the entire protocol. Thus, our results suggest that combined targeting of hematopoietic and hepatic Tfr2 may be a therapeutic option to balance erythropoiesis stimulation and iron increase, without affecting EPO levels.

Redefying the therapeutic strategies against cardiorenal morbidity and mortality: Patient phenotypes

Chronic kidney disease (CKD) patients face an unacceptably high morbidity and mortality, mainly from cardiovascular diseases. Diabetes mellitus, arterial hypertension and dyslipidemia are highly prevalent in CKD patients. Established therapeutic protocols for the treatment of diabetes mellitus, arterial hypertension, and dyslipidemia are not as effective in CKD patients as in the general population. The role of non-traditional risk factors (RF) has gained interest in the last decades. These entail the deranged clinical spectrum of secondary hyperparathyroidism involving vascular and valvular calcification, under the term “CKD-mineral and bone disorder” (CKD-MBD), uremia per se, inflammation and oxidative stress. Each one of these non-traditional RF have been addressed in various study designs, but the results do not exhibit any applied clinical benefit for CKD-patients. The “crusade” against cardiorenal morbidity and mortality in CKD-patients is in some instances, derailed. We propose a therapeutic paradigm advancing from isolated treatment targets, as practiced today, to precision medicine involving patient phenotypes with distinct underlying pathophysiology. In this regard we propose two steps, based on current stratification management of corona virus disease-19 and sepsis. First, select patients who are expected to have a high mortality, i.e., a prognostic enrichment. Second, select patients who are likely to respond to a specific therapy, i.e., a predictive enrichment.

The resistance to methoxy polyethylene glycol-epoetin beta in anemic patients of end-stage renal disease

Background

Chronic kidney disease (CKD) is a global disease, and the number of people affected is increasing due to driving factors such as diabetes, obesity, and hypertension, as well as increased life expectancy. Many patients with CKD suffer anemia throughout the period of their disease.

Aim

This research aimed to investigate the relation between resistance to the methoxy polyethylene glycol-epoetin beta (ME-β) and angiotensin-converting enzyme (ACE) gene polymorphism.

Methods

Seventy Iraqi patients with CKD on hemodialysis treatment for at least six months and receiving a subcutaneous injection of ME-β were selected to enroll in this current study. In addition to these patients, the control group of 20 healthy subjects. Baseline samples (Three blood samples) were obtained and withdrawn from each participant, then 3 and 6 months following the starting sample. In addition, a unique blood sample was taken from each participant in the control group in the early morning hours following 8 h of fasting and before dialysis (for the patients' group).

Results

ACE polymorphism did not demonstrate a significant (p ˃ 0.05) relation with changing the dose of ME-β. Furthermore, there was a negative relationship between ME-β dose and hemoglobin (Hb) in CKD patients. Comparing ACE polymorphism between good and hypo-response groups shows no significant effect (p ˃ 0.05) on ME-β therapy. Moreover, the erythropoietin resistance index (ERI) was significantly (p < 0.001) lower in good responders to ME-β therapy compared to the hypo-response group. Finally, comparing the ERI of the patient, the good response group to the hypo-response group showed no significant association (p ˃ 0.05) with ACE gene polymorphism in response to ME-β therapy.

Conclusion

No relation was determined between the polymorphism ACE gene and the resistance to the ME-β administration in CKD Iraqi patients.

Diagnostic accuracy and clinical usefulness of erythrocyte creatine content to predict the improvement of anaemia in patients receiving maintenance haemodialysis

BACKGROUND

The improvement of anaemia over time by erythropoiesis stimulating agent (ESA) is associated with better survival in haemodialysis patients. We previously reported that erythrocyte creatine content, a marker of erythropoietic capacity, was a reliable marker to estimate the effectiveness of ESA. The aim of this study was to examine the accuracy and clinical usefulness of erythrocyte creatine content to predict the improvement of anaemia in haemodialysis patients.

METHODS

ESA dose was fixed 3 months prior to the enrollment and was maintained throughout the study period. Erythrocyte creatine content and haematologic indices were measured at baseline in 92 patients receiving maintenance haemodialysis. Haemoglobin was also measured 3 months after. Improvement of anaemia was defined as ≥ 0.8 g/dL change in haemoglobin from baseline to 3 months.

RESULTS

Erythrocyte creatine content was significantly higher in 32 patients with improvement of anaemia compared to 60 patients with no improvement of anaemia (2.47 ± 0.74 vs. 1.57 ± 0.49 μmol/gHb, P = 0.0001). When 9 variables (erythrocyte creatine content, ESA dose, reticulocyte, haptoglobin, haemoglobin at baseline, serum calcium, intact parathyroid hormone, transferrin saturation and serum ferritin) were used in the multivariate logistic regression analysis, erythrocyte creatine emerged as the most important variable associated with the improvement of anaemia (P = 0.0001). The optimal cut-off point of erythrocyte creatine content to detect the improvement of anaemia was 1.78 μmol/gHb (Area under the curve: 0.86). Sensitivity and specificity of erythrocyte creatine content to detect the improvement of anaemia were 90.6% and 83.3%.

CONCLUSION

Erythrocyte creatine content is a reliable marker to predict the improvement of anaemia 3 months ahead in patients receiving maintenance haemodialysis.

Anemia biomarkers and mortality in hemodialysis patients with or without diabetes: A 10-year follow-up study

BACKGROUND

Many studies have assessed the association between anemia and mortality in hemodialysis but few compared patients with and without diabetes. Our study aims to investigate the impact of hemoglobin and iron parameters on mortality in hemodialysis patients with or without diabetes.

METHODS

This is a two-center retrospective study that included all adult patients who started hemodialysis between February 2012 and February 2020, followed until January 2021. Averages of hemoglobin, ferritin and transferrin saturation of entire follow-up were recorded. Kaplan Meier survival, log rank test and cox regression analyses were performed to assess the association between anemia biomarkers and mortality.

RESULTS

A total of 214 patients were included. Mean age was 67.98 ±12.41 years, mean hemoglobin was 10.92 ±0.75 g/dL, mean ferritin was 504.43 ± 221.42 ng/mL and mean transferrin saturation was 26.23 ±7.77%. Log rank test showed an association between hemoglobin ≥11 g/dL and better survival in patients without diabetes (P = 0.028). Based on cox regression analysis, hemoglobin was associated with all-cause mortality in all patients (HR = 0.66; CI:0.49,0.89; P = 0.007). When comparing patients with and without diabetes, this association remained significant only in patients without diabetes (HR = 0.53; CI:0.37,0.77; P<0.001). Based on different multivariate models, hemoglobin, ferritin and age were independent factors associated with mortality in patients without diabetes.

CONCLUSIONS

This study showed that hemoglobin ≥11 g/dL is associated with better survival in hemodialysis patients without diabetes but not in those with diabetes. These differences need to be further explored in other countries and settings. An individualization of the hemoglobin target level might be necessary to improve patients' outcomes.

Hemoglobin and Clinical Outcomes in Hemodialysis: An Analysis of US Medicare Data From 2018 to 2020

Rationale & Objective

Anemia management in patients treated with maintenance dialysis remains a challenge. We sought to update information in this area by evaluating the association between hemoglobin and various outcome and utilization measures using data-rich Medicare sources.

Study Design

Observational cohort study using data from the Consolidated Renal Operations in a Web-enabled Network and Medicare claims.

Setting & Participants

We studied 371,250 prevalent patients treated with hemodialysis, covering 3,326,072 patient-months in 2019.

Exposure

Monthly patient hemoglobin concentrations.

Outcomes

We examined several outcomes, including mortality, all-cause hospitalization, cause-specific hospitalization, and emergency department utilization in the month following the exposure measurement.

Analytical Approach

For each monthly observation period, we calculated unadjusted and adjusted (for demographics and comorbid condition) hazard ratios using Cox regression.

Results

The hemoglobin concentration was <10.5 g/dL for 40% of observations. We found an inverse association between mortality and hemoglobin measured over a range from <9 g/dL (HR, 2.53; 95% CI, 2.45-2.61; P < 0.0001, reference = 10.5-11 g/dL) to 11-11.5 g/dL (HR, 0.92; 95% CI, 0.89-0.96; P < 0.0001). Mortality risk started to increase at hemoglobin levels >11.5 g/dL. All-cause hospitalization, cause-specific hospitalization (including cardiovascular, infection, and several subcategories including coronavirus disease 2019 hospitalization), and emergency department utilization were inversely associated with hemoglobin concentration, with risk reduction stabilizing at hemoglobin levels of approximately 11.5-12 g/dL and higher.

Limitations

As with prior observational studies, the observed associations are not necessarily causal.

Conclusions

In a large US hemodialysis population, there were better clinical outcomes at higher hemoglobin concentrations over short exposure and follow-up periods, consistent with other observational studies that generally used longer exposure and follow-up times. Mortality risk increased at hemoglobin concentrations >11.5 g/dL, consistent with findings from erythropoiesis-stimulating agent clinical trials. The apparently beneficial short-term effects associated with higher hemoglobin concentrations suggest that hemoglobin measurements capture unmeasured elements of patient risk.

Responsiveness to an erythropoiesis-stimulating agent is correlated with body composition in patients undergoing chronic hemodialysis

BACKGROUND

Resistance to erythropoiesis-stimulating agents (ESA) is associated with adverse outcomes in patients undergoing chronic hemodialysis. However, the impact of body composition on ESA response remains uncertain. This study retrospectively investigated whether there is an association between the ESA resistance index (ERI) and body composition in patients undergoing chronic hemodialysis.

METHODS

Multifrequency bioelectrical impedance analysis was used to measure body composition every six months. The ERI was calculated by dividing the weekly body weight-adjusted erythropoietin dose by the hemoglobin concentration. The ERI values were recorded every three months.

RESULTS

A total of 123 patients were followed up for 24 (interquartile range 5, 75) months. The ERI was negatively correlated with body mass index, arm circumference, arm muscle circumference, body fat percentage, and visceral fat area (P = 0.057, 0.001, 0.017, 0.063, and 0.041, respectively). Patients with a higher mean ERI during the study period had an increased risk of all-cause mortality, cardiovascular events, and infection requiring hospitalization than those with a lower mean ERI (P = 0.027, 0.021, and 0.037, respectively). We also evaluated the association between the slope of body composition parameters and the ERI trend over time and found that the ERI increased over time in patients who had an increased ratio of extracellular water to total body water (P = 0.002) as well as decreased arm circumference, arm muscle circumference, visceral fat area, and phase angle (P = 0.001, P < 0.001, P = 0.036, and 0.002).

CONCLUSION

ESA responsiveness appears to be associated with body composition in patients undergoing chronic hemodialysis. Therefore, measures improving body composition, such as nutrition and exercise, may have a favorable effect on the response to ESA.

Association between haemoglobin concentration and intradialytic hypotension in patients undergoing maintenance haemodialysis: a retrospective cohort study

OBJECTIVES

Haemoglobin concentration is a potentially modifiable factor that may help lower the risk of intradialytic hypotension (IDH), but its association with IDH is not well understood. This study aimed to clarify the relationship between haemoglobin concentration and IDH.

DESIGN

Retrospective cohort study.

SETTING

We evaluated patients undergoing maintenance haemodialysis in December 2017 at Rakuwakai Otowa Kinen Hospital.

PARTICIPANTS

A total of 543 patients were included. We defined exposure according to the following five categories depending on haemoglobin concentrations by 1.0 increments: <9.0, ≥9.0 to <10.0, 10.0 to <11.0, ≥11.0 to <12.0 and ≥12.0 g/dL.

PRIMARY OUTCOME MEASURE

The primary outcome of interest was the development of IDH, defined as any nadir <100 mm Hg if the pre-dialysis systolic blood pressure (SBP) was ≥160 mm Hg or any nadir <90 mm Hg if the pre-dialysis SBP was <160 mm Hg (IDH_nadir).

RESULTS

Overall, IDH_nadir occurred in 14.3% (465/3250) of the sessions. With a haemoglobin concentration of ≥10.0 to <11.0 g/dL set as reference, the adjusted ORs for IDH_nadir were 0.82 (95% CI, 0.32 to 2.15), 1.16 (95% CI, 0.56 to 2.39), 1.26 (95% CI, 0.68 to 2.36) and 3.01 (95% CI, 1.50 to 6.07) for haemoglobin concentrations of <9.0, ≥9.0 to <10.0, ≥11.0 to <12.0 and ≥12.0 g/dL, respectively. In the cubic spline analysis, a high haemoglobin concentration was associated with the development of IDH_nadir.

CONCLUSION

High haemoglobin concentration is associated with IDH, and thus, the upper limit of haemoglobin concentration should be closely monitored in patients with IDH.

Anemia in Chronic Kidney Disease Patients: An Update

Chronic kidney disease (CKD) is one of the most common disabling diseases globally. The main etiopathology of CKD is attributed to progressive renal fibrosis secondary to recurrent renal insults. Anemia is a known complication in CKD patients, associated with higher hospitalization rates and increased mortality risk. CKD-associated anemia (CKD-AA) is either due to true iron deficiency and/or functional iron deficiency anemia. There is new emerging evidence about the effects of erythropoiesis stimulating agents in the treatment of CKD-AA and their role in reversing and preventing kidney fibrosis in the early stages of CKD. This effect potentially provides new scopes in the prevention and treatment of CKD-AA and in decreasing the progression of CKD and the associated long-term complications. Epidemiology, pathophysiology, and treatments of CKD-AA will be discussed.

Efficacy and safety of intravenous iron with different frequencies for renal anaemia: A systematic review and meta-analysis

WHAT IS KNOWN AND OBJECTIVE

To evaluate the efficacy and safety of intravenous iron supplementation in patients with renal anaemia.

METHODS

We searched the PubMed, Embase, Cochrane Library, and Web of Science from their inception until 17 September 2021, for randomized controlled trials (RCTs) to evaluate the efficacy and safety of intravenous iron at different frequencies. The observed efficacy indicators included transfer saturation (TSAT), serum ferritin (SF) and haemoglobin (HGB). Outcomes of interest included allergies, infections, all-cause mortality and cardiovascular events.

RESULTS AND DISCUSSION

Of the 751 eligible studies, 7 RCTs met the inclusion criteria. The RCTs showed that there were no significant differences between the low-frequency high-dose group (1-2 doses, >200 mg/dose) and the high-frequency low-dose group (4-5 doses, ≤200 mg/dose) in the increase in TSAT (WMD = 1.90; 95% CI = -2.04 to 5.84; I²  = 0%), SF (WMD = 15.70; 95% CI = -32.20 to 70.61; I²  = 0%) and HGB (WMD = -0.00; 95% CI = -0.43 to 0.42; I²  = 0%). There was also no significant difference in the occurrence of outcome events, including allergies (RR = 1.84; 95% CI = 0.95 to 3.57; I²  = 45%), infections (RR = 0.61; 95% CI = 0.20-1.86; I²  = 0%), cardiovascular events (RR = 0.88; 95% CI = 0.67-1.15; I²  = 48%) and all-cause mortality (RR = 0.74; 95% CI = 0.40-1.35; I²  = 0%).

WHAT IS NEW AND CONCLUSION

Frequencies of intravenous iron supplementation with similar doses share similar safety and efficacy in patients with renal anaemia. However, a single dose or two doses of intravenous iron are more cost-effective and patient friendly. These findings may provide evidence for the clinical application of intravenous iron supplementation for patients with renal anaemia.

A Phase 3 Study of Enarodustat (JTZ-951) in Japanese Hemodialysis Patients for Treatment of Anemia in Chronic Kidney Disease: SYMPHONY HD Study

INTRODUCTION

Enarodustat (JTZ-951) is a new oral hypoxia-inducible factor-prolyl hydroxylase inhibitor for the treatment of anemia in chronic kidney disease (CKD). We conducted a phase 3 study to compare the efficacy and safety of enarodustat with darbepoetin alfa (DA) in Japanese anemic patients with CKD receiving maintenance hemodialysis.

METHODS

Subjects receiving maintenance hemodialysis were randomly assigned at a 1:1 ratio to receive oral enarodustat once daily or intravenous DA every week for 24 weeks with dose adjustment every 4 weeks to maintain hemoglobin (Hb) within a target range (≥10.0 to <12.0 g/dL). The primary efficacy endpoint was difference in mean Hb level between arms during the evaluation period defined as weeks 20-24 (noninferiority margin: -1.0 g/dL). Intravenous iron preparations were prohibited during the screening period and during weeks 0-4.

RESULTS

The mean Hb level of each arm during the evaluation period was 10.73 g/dL (95% confidence interval [CI]: 10.56, 10.91) in the enarodustat arm and 10.85 g/dL (95% CI: 10.72, 10.98) in the DA arm. The difference in the mean Hb level between arms was -0.12 g/dL (95% CI: -0.33, 0.10), confirming the noninferiority of enarodustat to DA. The mean Hb level of each arm was maintained within the target range during the treatment period. Increased total iron-binding capacity and serum iron and decreased hepcidin were observed through week 4 in the enarodustat arm albeit after switching from erythropoiesis-stimulating agents. No apparent safety concerns of enarodustat were observed compared with DA.

DISCUSSION/CONCLUSION

Enarodustat was noninferior to DA for the treatment of anemia in CKD patients receiving maintenance hemodialysis and was generally well tolerated over 24 weeks.

Associations of hemoglobin and change in hemoglobin with risk of incident hip fracture in older men and women: the cardiovascular health study

In a multi-site longitudinal cohort study, decreasing hemoglobin was associated with increased hip fracture risk in men. Anemia was associated with hip fracture in men and in African American women. Decreasing hemoglobin may be a marker of progressing bone fragility, making its serial measurement useful for fracture risk stratification.

INTRODUCTION

Hematopoiesis and bone health are interdependent. Anemia has been associated with risk of fracture in humans. To further elucidate this relationship, we hypothesized that decreasing hemoglobin could indicate defective hematopoiesis and would also predict fracture risk.

METHODS

We performed a prospective analysis from study baseline (1992) of the Cardiovascular Health Study, a multi-site longitudinal cohort study. A total of 4670 men and women, ages >65 years, who were able to consent and not institutionalized or wheelchair bound, had hemoglobin (Hb) measured in 1992. For 4006 subjects, Hb change from 1989 to 1992 was annualized and divided into sex-specific quartiles. Incident hip fractures were verified against Medicare claims data during a median follow-up of 11.8 years.

RESULTS

Nested Cox proportional-hazard models estimated association of hip fracture with anemia (men Hb <13 g/dL, women Hb <12 g/dL) and separately, greatest Hb decrease (versus others). Anemia was associated with increased hip fracture risk in all men (HR 1.59; 95% CI 1.01-2.50) and African American women (HR 3.21; 95% CI 1.07-9.63). In men, an annualized Hb loss of >0.36 g/dL/year was associated with a higher risk of hip fracture (HR 1.67; 95% CI 1.10-2.54), which was lessened by anemia at the start of fracture follow-up (HR 1.53; 95% CI 0.99-2.39).

CONCLUSIONS

Decreasing Hb may be an early marker for subsequent hip fracture risk in men, which may be less informative once an anemia threshold is crossed. Only African American women with anemia had increased hip fracture risk, suggesting a race difference in this relationship.

Ferric Citrate Dosing in Iron Deficiency Anemia in Nondialysis-Dependent Chronic Kidney Disease

INTRODUCTION

Ferric citrate (FC) is indicated as an oral iron replacement for iron deficiency anemia in adult patients with chronic kidney disease (CKD) not on dialysis. The recommended starting dose is one 1-g tablet three times daily (TID). This study investigated long-term efficacy and safety of different FC dosing regimens for treating anemia in nondialysis-dependent CKD (NDD-CKD).

METHODS

In this phase 4, randomized, open-label, multicenter study, patients with anemia with NDD-CKD (estimated glomerular filtration rate, ≥20 mL/min and <60 mL/min) were randomized 1:1 to one FC tablet (1-g equivalent to 210 mg ferric iron) TID (3 g/day) or 2 tablets twice daily (BID; 4 g/day). At week 12, dosage was increased to 2 tablets TID (6 g/day) or 3 tablets BID (6 g/day) in patients whose hemoglobin (Hb) levels increased <0.5 g/dL or were <10 g/dL. Primary endpoint was mean change in Hb from baseline to week 24.

RESULTS

Of 484 patients screened, 206 were randomized and 205 received FC. Mean (standard deviation) changes from baseline in Hb at week 24 were 0.77 (0.84) g/dL with FC TID 3 g/day and 0.70 (0.98) g/dL with FC BID 4 g/day.

DISCUSSION/CONCLUSIONS

FC administered BID and TID for 48 weeks was safe and effective for treating anemia in this population, supporting potentially increased dosing flexibility.

Erratum: Interdialytic Weight Gain Effects on Hemoglobin Concentration and Cardiovascular Events

[This corrects the article DOI: 10.1016/j.ekir.2021.05.015.][This corrects the article DOI: 10.1016/j.ekir.2020.07.027.].

Relationships among the Dosage of Erythropoiesis-Stimulating Agents, Erythropoietin Resistance Index, and Mortality in Maintenance Hemodialysis Patients

BACKGROUND

Erythropoiesis-stimulating agents (ESAs) constitute an important treatment option for anemia in hemodialysis (HD) patients. We investigated the relationships among the dosage of ESA, erythropoietin resistance index (ERI) scores, and mortality in Chinese MHD patients.

METHODS

This multicenter observational retrospective study included MHD patients from 16 blood purification centers (n = 824) who underwent HD in 2011-2015 and were followed up until December 31, 2016. We collected demographic variables, HD parameters, laboratory values, and ESA dosages. Patients were grouped into quartiles according to ESA dosage to study the effect of ESA dosage on all-cause mortality. The ERI was calculated as follows: ESA (IU/week)/weight (kg)/hemoglobin levels (g/dL). We also compared outcomes among the patients stratified into quartiles according to ERI scores. We used the Cox proportional hazards model to measure the relationships between the ESA dosage, ERI scores, and all-cause mortality. Using propensity score matching, we compared mortality between groups according to ERI scores, classified as either > or ≤12.80.

RESULTS

In total, 824 patients were enrolled in the study; 200 (24.3%) all-cause deaths occurred within the observation period. Kaplan-Meier analyses showed that patients administered high dosages of ESAs had significantly worse survival than those administered low dosages of ESAs. A multivariate Cox regression identified that high dosages of ESAs could significantly predict mortality (ESA dosage >10,000.0 IU/week, HR = 1.59, 95% confidence intervals (CIs) (1.04, 2.42), and p = 0.031). Our analysis also indicated a significant increase in the risk of mortality in patients with high ERI scores. Propensity score matching-analyses confirmed that ERI > 12.80 could significantly predict mortality (HR = 1.56, 95% CI [1.11, 2.18], and p = 0.010).

CONCLUSIONS

Our data suggested that ESA dosages >10,000.0 IU/week in the first 3 months constitute an independent predictor of all-cause mortality among Chinese MHD patients. A higher degree of resistance to ESA was related to a higher risk of all-cause mortality.

Development and Validation of a Transfusion Risk Score for Patients Receiving Maintenance Hemodialysis

BACKGROUND

In patients on dialysis with anemia, avoiding red blood cell transfusions is preferable. We sought to develop and validate a novel transfusion prediction risk score for patients receiving maintenance hemodialysis.

METHODS

This retrospective cohort study used United States Renal Data System data to create a model development cohort (patients who were point prevalent and on hemodialysis on November 1, 2012) and a validation cohort (patients who were point prevalent and on hemodialysis on August 1, 2013). We characterized comorbidity, inflammatory conditions, hospitalizations, anemia and anemia management, iron parameters, intravenous iron use, and vitamin D use during a 6-month baseline period to predict subsequent 3-month transfusion risk. We used logistic least absolute shrinkage and selection operator regression. In an exploratory analysis, model results were used to calculate a score to predict 6- and 12-month hospitalization and mortality.

RESULTS

Variables most predictive of transfusion were prior transfusion, hemoglobin, ferritin, and number of hospital days in the baseline period. The resulting c-statistic in the validation cohort was 0.74, indicating relatively good predictive power. The score was associated with a significantly increased risk of subsequent mortality (hazard ratios 1.0, 1.22, 1.26, 1.54, 1.71, grouped from lowest to highest score), but not with hospitalization.

CONCLUSIONS

We developed a transfusion prediction risk score with good performance characteristics that was associated with mortality. This score could be further developed into a clinically useful application, allowing clinicians to identify patients on hemodialysis most likely to benefit from a timely, proactive anemia treatment approach, with the goal of avoiding red blood cell transfusions and attendant risks of adverse clinical outcomes.

Association between anemia and mortality in hemodialysis patients is modified by the presence of diabetes

BACKGROUND

The prevalence and severity of anemia differ between diabetic and non-diabetic patients. We investigated whether the effect of hemoglobin (Hb) on patient outcome was affected by the presence or absence of diabetes among Japanese patients receiving chronic hemodialysis (HD).

METHODS

We enrolled 149,308 patients from a nationwide dialysis registry in Japan at the end of 2012 (mean age, 67.6 ± 12.3 years; male, 61.7%; diabetes, 43.5%; median dialysis duration, 65 months) who underwent three HD sessions weekly. One-year all-cause and cardiovascular (CV) mortality were assessed using Cox regression analysis and competing-risks regression analysis. We used multiple imputation to deal with missing covariate data.

RESULTS

Baseline Hb and serum ferritin levels were independently associated with all-cause and CV mortality. In non-diabetic patients, a significantly higher risk for all-cause mortality compared to the reference group (10 to 11 g/dL) was observed in patients with Hb < 8 g/dL (hazard ratio (HR): 1.266; 95% confidence interval (CI) 1.097-1.460) and 8 to  9 g/dL(HR: 1.153; 95% CI 1.030-1.290). On the other hand, diabetic HD patients in the same Hb category group did not have increased risk of all-cause mortality.

CONCLUSIONS

We found that non-diabetic HD patients had an increased risk of all-cause mortality if they had lower Hb levels, whereas the effect of Hb levels on mortality was attenuated in diabetic HD patients. These data suggest that the association between Hb levels and mortality rate could be different between diabetic and non-diabetic HD patients.

Shengxuening versus Oral Iron Supplementation for the Treatment of Renal Anemia: A Systematic Review

Shengxuening (SXN), as an effective supplement to heme-like iron, has been widely used in China to treat renal anemia. However, proof of its use for improving inflammation is scarce in the past decades. This work aimed to evaluate the effectiveness of SXN with inflammatory factors as primary endpoints. By searching PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), China Biology Medicine disc (CBM), VIP Information/ China Science and Technology Journal Database, and WANFANG Database, we identified previous studies that met the inclusion criteria and included them in the systematic review. Analyses were performed using STATA. Nine randomized controlled trials were included in this systematic review. The results revealed that, when compared with oral iron supplementation, SXN can reduce the level of inflammatory factors, including hs-CRP (WMD -1.93 mg/L; 95% CI -2.14 to -1.72), IL-6 (P< 0.05), and TNF-α (P< 0.05), and significantly enhance the level of Hb (WMD 13.40 g/L; 95% CI 12.95 to 13.84), TSAT (WMD 6.88%; 95% CI 6.50 to 7.26), and SF (WMD 38.46 μg/L; 95% CI 23.26 to 53.67). Moreover, SXN exhibits a superior security than oral iron supplementation with less gastrointestinal adverse reactions (RR 0.14; 95% CI 0.06 to 0.32). In patients with renal anemia, SXN is more efective and safer than oral iron supplementation, especially in reducing the level of inflammation.

Mortality and Hospitalizations among Sickle Cell Disease Patients with End-Stage Kidney Disease Initiating Dialysis

BACKGROUND

Sickle cell disease (SCD) is the most common inherited hematological disorder and a well-described risk factor for end-stage kidney disease (ESKD). Mortality and hospitalizations among patients with SCD who develop ESKD remain understudied. Furthermore, prior studies focused only on SCD patients where ESKD was caused by SCD. We aimed to describe mortality and hospitalization risk in all SCD patients initiating dialysis and explore risk factors for mortality and hospitalization.

METHODS

We performed a national observational cohort study of African American ESKD patients initiating dialysis (2000-2014) in facilities affiliated with a large dialysis provider. SCD was identified by diagnosis codes and matched to a reference population (non-SCD) by age, sex, dialysis initiation year, and geographic region of care. Sensitivity analyses were conducted by restricting to patients where SCD was recorded as the cause of ESKD.

RESULTS

We identified 504 SCD patients (mean age: 47 ± 14 years; 48% females) and 1,425 reference patients (mean age: 46 ± 14 years; 49% females). The median follow-up was 2.4 (IQR 1.0-4.5) years. Compared to the reference, SCD was associated with higher mortality risk (hazard ratio 1.66; 95% confidence interval [CI]: 1.36-2.03) and higher hospitalization rates (incidence rate ratio 2.12; 95% CI: 1.88-2.38) in multivariable analyses. Exploratory multivariable mortality risk models showed the largest mortality risk attenuation with the addition of time-varying hemoglobin and high-dose erythropoietin, but the association of SCD with mortality remained significant. Sensitivity analyses (restricted to ESKD caused by SCD) also showed significant associations between SCD and mortality and hospitalizations, but with larger effect estimates. High-dose erythropoietin was associated with the highest risk for mortality and hospitalization in SCD.

CONCLUSIONS

Among ESKD patients, SCD is associated with a higher risk for mortality and hospitalization, particularly in patients where SCD is identified as the cause of ESKD.

Epoetin alfa-epbx: a new entrant into a crowded market. a historical review of the role of erythropoietin stimulating agents and the development of the first epoetin biosimilar in the United States

Introduction: Erythropoietin stimulating agents (ESAs) have been established both to correct anemia and provide the clinical benefits of increased exercise capacity, reduced transfusion requirements, and improved quality of life. An increase in physician and patient adoption of biosimilars, as well as changes to healthcare reimbursement policies, have driven market competitors to innovate and expand the range of biosimilar products. While erythropoietin biosimilars have been approved by the EMA since 2007, the FDA's approval of epoetin alfa-epbx in 2018 marks the first erythropoietin biosimilar approved in the United States. Areas covered: In this article, we critically review the biology, clinical use, manufacturing, safety, and efficacy of ESAs and erythropoietin biosimilars. We then review the regulatory framework and potential impact on healthcare costs offered by erythropoietin biosimilars. Expert opinion: Due to the complex nature of manufacturing large-molecule biologics, it is important to recognize the challenges to quality assurance and overall safety posed by the introduction of biosimilars, which undergo much more limited clinical testing than their reference biologic product before coming to market. With many biologic therapies nearing patent expiration, biosimilars will become increasingly common in clinical practice. Ensuring patient safety with these products will require increased post-marketing surveillance and awareness from prescribers.

Survival Percentile and Predictors of Difference in Survival among Hemodialysis Patients and Their Additive Interaction Using Laplace Regression

Background: Identifying survival modifiable factors and additive interaction between them could help in prioritizing the clinical care of Hemodialysis (HD) patients. We aimed to examine the survival rate and its predictors in HD patients; and explore the additive interaction between survival modifiable factors.

Study design: A retrospective cohort study.

Methods: The present study was performed on 1142 HD patients in Hamadan Province, western Iran from 2007 to 2017. Data were collected through a researcher-made checklist on hospital records. Laplace regression was used to evaluate differences in 40^th survival percentiles in different levels of predictors as well as exploring the pairwise additive interactions between variables.

Results: We observed significantly higher survival in nonsmoker patients (40^th percentile difference = 5.34 months, 95% CI: 2.06, 8.61). Survival was shorter by more than 3 years in CRP positive patients (40^th percentile difference=36.9 months, 95% CI: 32.37, 41.42). Patients with normal albumin (40^th percentile difference =24.92, 95% CI: 18.04, 31.80) and hemoglobin (40^th percentile difference = 18.65, 95% CI: 12.43, 24.86) had significantly higher survival (P<0.001). There was super-additive interaction between being CRP negative and nonsmoker (β₃ = 9.42 months, 95% CI: 3.35, 15.49 (P=0.002)).

Conclusion: High CRP and low serum albumin and hemoglobin were associated with the increased risk of death in HD patients. The results of this study support the presence of super-additive interaction between CRP status with serum hemoglobin and also CRP status with smoking, resulting in excess survival in HD patients.

Effect of hypoxia-inducible factor-prolyl hydroxylase inhibitors on anemia in patients with CKD: a meta-analysis of randomized controlled trials including 2804 patients

Hypoxia-inducible factor-prolyl hydroxylase inhibitors (HIF-PHIs) are orally active first-in-class new generation drugs for renal anemia. This extensive meta-analysis of randomized controlled trials (RCTs) was designed to provide clear information on the efficacy and safety of HIF-PHIs on anemia in chronic kidney disease (CKD) patients. Searches included PubMed, Web of Science, Ovid MEDLINE, and Cochrane Library database up to October 2019. RCTs of patients with CKD comparing HIF-PHIs with erythropoiesis-stimulating agents (ESAs) or placebo in the treatment of anemia. The primary outcome was hemoglobin change from baseline (Hb CFB); the secondary outcomes included iron-related parameters and the occurrence of each adverse event. 26 trials in 17 articles were included, with a total of 2804 dialysis or patients with CKD. HIF-PHIs treatment produced a significant beneficial effect on Hb CFB compared with the placebo group (MD, 0.69; 95% CI, 0.36 to 1.02). However, this favored effect of HIF-PHIs treatment was not observed in subgroup analysis among trials compared with ESAs (MD, 0.06; 95% CI, -0.20 to 0.31). The significant reduction in hepcidin by HIF-PHIs was observed in all subgroups when compared with the placebo group, whereas this effect was observed only in NDD-CKD patients when compared with ESAs. HIF-PHIs increased the risk of nausea (RR, 2.20; 95% CI, 1.06 to 4.53) and diarrhea (RR, 1.75; 95% CI, 1.06 to 2.92). We conclude that orally given HIF-PHIs are at least as efficacious as ESAs treatment to correct anemia short term in patients with CKD. In addition, HIF-PHIs improved iron metabolism and utilization in patients with CKD.

Latest Strategy in Renal Anemia Management in Peritoneal Dialysis Patients

The target of renal anemia correction with erythropoietin stimulating agents (ESAs) has been traditionally set at a hemoglobin (Hb) level of 11 – 12 g/dL. However, a trend has arisen of progressively increasing the Hb level to beyond 12 g/dL. Recent randomized control trials (RCTs) on correction of renal anemia in chronic kidney disease patients found that normalization of anemia to above 13 g/dL was associated with negative outcome parameters, echoing a previous RCT that showed increased death and myocardial infarction risk after normalization of hemoglobin level in hemodialysis patients. The latest consensus is to limit Hb to a level not exceeding 13 g/dL during renal anemia correction with ESAs.

Currently, there are three ESAs available commercially. The choice of ESA should consider safety of subcutaneous administration, cost-effectiveness, and dosing frequency, all of which may affect compliance with ESA administration. Early identification of, and an early search for the causes of hyporesponsiveness to, ESAs is needed to avoid unnecessary escalation in the dose of ESAs. These approaches will help to improve the cost-effectiveness of ESA therapy and permit early detection of hidden problems. The current definitions of hyporesponsiveness are far too stringent and should be reviewed.

Interdialytic Weight Gain Effects on Hemoglobin Concentration and Cardiovascular Events

Introduction

Although predialysis hemoglobin concentration is affected by interdialytic weight gain (IDWG), the interaction between these parameters is not well understood.

Methods

Using data from the Japanese Dialysis Outcomes and Practice Pattern Study phases 1-5, we analyzed patients who underwent maintenance hemodialysis. The exposure variable was hemoglobin concentration, and the effect modifier was IDWG at baseline. These 2 categorical variables were then combined and analyzed. The primary outcome was major adverse cardiovascular events (MACEs). Hazard ratios were estimated using a Cox model for the association between exposure and MACEs after adjusting for potential confounders. We examined additive interactions between hemoglobin concentration and IDWG by calculating the relative excess risk due to interaction, which is defined as a departure from the additivity of effects.

Results

A total of 8234 patients were enrolled. During a median follow-up of 2.1 years, 1062 (12.9%) patients developed MACEs. In IDWG categories of <6%, adjusted hazard ratios for MACEs tended to be lower as hemoglobin concentration increased. In IDWG categories of ≥6%, point estimation of MACEs with hemoglobin concentration of ≥11.0 g/dl-<12.0 g/dl was higher than that with hemoglobin concentration of ≥10.0 g/dl-<11.0 g/dl. The relative excess risk due to interaction was 0.22 (95% confidence interval 0.02-0.42) between IDWG category of ≥6% and hemoglobin categories of ≥11.0 g/dl-<12.0 g/dl, indicating a synergistic interaction.

Conclusions

The association between hemoglobin concentration and MACEs differed across IDWG. Consideration should be given to the upper limit of hemoglobin concentration in patients with high IDWG.

A faster decline of residual kidney function and erythropoietin stimulating agent hyporesponsiveness in incident hemodialysis patients

INTRODUCTION

Erythropoietin stimulating agents (ESA) hyporesposiveness has been associated with increased mortality in hemodialysis (HD) patients. However, the impact of decline of residual kidney function (RKF) on ESA hyporesposiveness has not been adequately elucidated among patients receiving HD.

METHODS

The associations of RKF decline with erythropoietin resistance index (ERI; average weekly ESA dose [units])/post-dialysis body weight [kg]/hemoglobin [g/dL]) were retrospectively examined across four strata of annual change in RKF (residual renal urea clearance [KRU] < -3.0, -3.0 to <-1.5, -1.5 to <0, ≥0 mL/min/1.73 m² per year; urinary volume < -600, -600 to<-300, -300 to <0, ≥0 mL/day per year) using logistic regression models adjusted for clinical characteristics and laboratory variables in 5239 incident HD patients in a large US dialysis organization between 1 January 2007 and 31 December 2011.

FINDINGS

The median values of the annual change in KRU and urinary volume were -1.2 (interquartile range [IQR]: -2.8 to 0.1) mL/min/1.73 m² per year and -250 (IQR: -600 to 100) mL/day per year. A faster KRU decline in the first year of HD was associated with higher odds for ESA hyporesponsiveness: KRU decline of <-3.0, -3.0 to <-1.5, and -1.5 to <0/min/1.73 m² per year were associated with adjusted odds ratios (OR) of 2.07 (95% confidence interval [CI]: 1.66-2.58), 1.54 (95%CI: 1.28-1.85), and 1.26 (95%CI: 1.07-1.49), respectively (reference: ≥0 mL/min/1.73 m² per year). These associations were consistent across strata of baseline KRU, age, sex, race, diabetes, congestive heart failure, hemoglobin, and serum albumin. Sensitivity analyses using urinary volume as another index of RKF showed consistent associations.

DISCUSSION

A faster RKF decline during the first year of dialysis was associated with ESA hyporesponsiveness and low hemoglobin levels among incident HD patients.

Predictors of mortality among hemodialysis patients in Hamadan province using random survival forests

Background

Hemodialysis patients are at a high risk for morbidity and mortality. This study aimed to find the predictors of mortality and survival in hemodialysis patients in Hamadan province of Iran.

Methods

A number of 785 patients during the entire 10 years were enrolled into this historical cohort study. Data were gathered by a checklist of hospital records. The survival time was the time between the start of hemodialysis treatment to patient’s death as the end point. Random survival forests (RSF) method was used to identify the main predictors of survival among the patients.

Results

The median survival time was 613 days. The number of 376 deaths was occurred. The three most important predictors of survival were hemoglobin, CRP and albumin. RSF method predicted survival better than the conventional Cox-proportional hazards model (out-of-bag C-index of 0.808 for RSF vs. 0.727 for Cox model).

Conclusions

We found that positivity of CRP, low serum albumin and low serum hemoglobin were the top three most important predictors of low survival for HD patients

Efficacy and Safety of CKD-11101 (Proposed Biosimilar of Darbepoetin-Alfa) Compared with Darbepoetin-Alfa in Patients on Hemodialysis: A Randomized, Double-Blinded, Parallel-Group Phase III Study

BACKGROUND

Darbepoetin-alfa is an erythropoiesis-stimulating agent (ESA) with a long elimination half-life that achieves better hemoglobin (Hb) stability than short-acting ESAs.

OBJECTIVE

We aimed to evaluate the efficacy and safety of intravenous CKD-11101 (a biosimilar of darbepoetin-alfa) compared with those of darbepoetin-alfa in hemodialysis patients.

METHODS

The study was performed in 24 centers in Korea between June 2015 and June 2017. The study subjects were randomized in a double-blind manner. The follow-up duration was 24 weeks, which consisted of 20 weeks of maintenance and 4 weeks of evaluation period. All patients underwent a stabilization period to achieve a target baseline Hb of 10-12 g/dL before randomization. Following randomization, patients received darbepoetin-alfa or CKD-11101 weekly or biweekly.

RESULTS

A total of 403 patients were randomized into two groups, and a total of 325 patients (80.6%) completed the investigation. The differences between the two groups in terms of change in the average Hb level from baseline to evaluation were not significant. The average administered dose of ESA was similar between the groups. There was no difference in the proportion of patients who maintained the target Hb during the evaluation period [60.4% vs. 66.2% in the CKD-11101 and darbepoetin-alfa groups, respectively (p = 0.3038)]. In addition, the safety analysis, consisting of adverse events and adverse drug reactions, showed comparable results between the two groups.

CONCLUSION

The changes in the level of Hb, dose of erythropoietin, and achievement rate of the target Hb during the study period were comparable between the groups. CKD-11101 has an equivalent efficacy and safety compared with darbepoetin-alfa in patients undergoing hemodialysis.

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.

The Impact of CKD Anaemia on Patients: Incidence, Risk Factors, and Clinical Outcomes-A Systematic Literature Review

Anaemia is a common consequence of chronic kidney disease (CKD); however, the risk factors for its development and its impact on outcomes have not been well synthesised. Therefore, we undertook a systematic review to fully characterise the risk factors associated with the presence of anaemia in patients with CKD and a contemporary synthesis of the risks of adverse outcomes in patients with CKD and anaemia. We searched MEDLINE, EMBASE, and the Cochrane Library from 2002 until 2018 for studies reporting the incidence or prevalence of anaemia and associated risk factors and/or associations between haemoglobin (Hb) or anaemia and mortality, major adverse cardiac events (MACE), hospitalisation, or CKD progression in adult patients with CKD. Extracted data were summarised as risk factors related to the incidence or prevalence of anaemia or the risk (hazard ratio (HR)) of outcome by Hb level (<10, 10-12, >12 g/dL) in patients not on dialysis and in those receiving dialysis. 191 studies met the predefined inclusion criteria. The risk factor most associated with the prevalence of anaemia was CKD stage, followed by age and sex. Mean HRs (95% CI) for all-cause mortality in patients with CKD on dialysis with Hb <10, 10-12, and >12 g/dL were 1.56 (1.43-1.71), 1.17 (1.09-1.26), and 0.91 (0.87-0.96), respectively. Similar patterns were observed for nondialysis patients and for the risks of hospitalisation, MACE, and CKD progression. This is the first known systematic review to quantify the risk of adverse clinical outcomes based on Hb level in patients with CKD. Anaemia was consistently associated with greater mortality, hospitalisation, MACE, and CKD progression in patients with CKD, and risk increased with anaemia severity. Effective treatments that not only treat the anaemia but also reduce the risk of adverse clinical outcomes are essential to help reduce the burden of anaemia and its management in CKD.

Economic Benefits of Switching From Intravenous to Subcutaneous Epoetin Alfa for the Management of Anemia in Hemodialysis Patients

Background:

Erythropoiesis-stimulating agents including epoetin alfa have been a mainstay of anemia management in patients with chronic kidney disease. Although the standard practice has been to administer epoetin alfa to patients on hemodialysis (HD) intravenously (IV), subcutaneous (SQ) epoetin alfa is longer acting and achieve the same target hemoglobin level to be maintained at a reduced dose and cost.

Objective:

The primary objective of this study was to determine the economic benefits of change in route of epoetin alfa administration from IV to SQ in HD patients. The secondary objectives were (1) to determine the differences in epoetin alfa doses at the pre-switch (IV) and post-switch period (SQ) and (2) to determine serum hemoglobin concentration, transferrin saturation, ferritin level, IV iron dose and cost in relationship to route of epoetin alfa administration.

Design:

This retrospective observational study included patients who transitioned from IV to SQ epoetin alfa.

Setting:

Two HD sites in southern Saskatchewan (Regina General Hospital, and Wascana Dialysis Unit, Regina) and 2 sites in northern Saskatchewan (St. Paul’s [SPH] Hospital, and SPH Community Renal Health Center, Saskatoon).

Patients:

The study includes 215 patients who transitioned from IV to SQ and were alive at the end of 12-month follow-up period.

Measurements:

We calculated the dose and cost of different routes of epoetin alfa administration/patient month. Also, serum hemoglobin, markers of iron stores (transferrin saturation and ferritin), IV iron dose, and cost were determined in relation to route of epoetin alfa administration.

Methods:

Data were gathered from 6 months prior (IV) to 12 months after switching treatment to SQ. The paired t-test and Wilcoxon signed-rank test were used to compare variables between pre-switch (IV) and post-switch (SQ) period.

Results:

The median cost (interquartile range) of epoetin alfa/patient-month decreased from (CAD508.3 [CAD349-CAD900.8]) pre-switch (IV) to (CAD381.2 [CAD247-CAD681]) post-switch (SQ) (P < .001), a decrease of 25%. The median epoetin alfa dose/patient-month reduced from (38 500 [25 714.3-64 166.5] international unit) pre-switch to (26 750.3 [17 362.6-48 066] IU) post-switch (P < .001), a decrease of 30.51%. The mean hemoglobin concentration (± standard deviation) for patients in both periods remained stable (103.3 ± 9.2 vs 104.3 ± 13.3 g/L, P = .34) and within the target range. There were no significant differences in transferrin saturation, ferritin, and IV iron dose and cost between the 2 study periods.

Limitations:

We were unable to consistently obtain information across all the sites on hospitalizations, inflammatory markers, nutritional status, and gastrointestinal bleeding. In addition, as our study sample was subject to survival bias, we cannot generalize our study results to other populations.

Conclusions:

We have shown that administering epoetin alfa SQ in HD patients led to a 30.51% reduction in dose and 25% reduction in cost while achieving equivalent hemoglobin levels. Given the cost sparing advantages without compromising care while achieving comparable hemoglobin levels, HD units should consider converting to SQ mode of administration.

Trial registration:

The study was not registered on a publicly accessible registry as it was a retrospective chart review and exempted from review by the Research Ethics Board of the former Regina Qu’Appelle Health Region.

Racial differences in utilization and outcomes of hemodialysis access in the Unites States

OBJECTIVE

To evaluate patterns of use and outcomes of arteriovenous fistulas and prosthetic grafts within racial categories in a large population based cohort of hemodialysis (HD) patients in the United States.

METHODS

A retrospective analysis of white, black, and Hispanic patients in the prospectively maintained United States Renal Database System who had an autogenous fistula or prosthetic graft placed for HD access between January 2007 and December 2014 was performed. Analysis of variance, χ2, t-tests, Kaplan-Meier, log-rank tests, multivariable logistic, and Cox regression analyses were used to evaluate maturation, patency, infection, and mortality.

RESULTS

This study of 359,942 patients, composed of 285,781 autogenous fistulas (79.4%) and 74,161 prosthetic grafts (20.6%) placed in 213,877 white (59.4%), 115,727 black (32.2%), and 30,338 Hispanic (8.4%) patients. There was a 11% increase in the risk-adjusted odds of HD catheter use as bridge to autogenous fistula placement in blacks (adjusted odds ratio, 1.11; 95% confidence interval [CI], 1.08-1.14; P < .001) and a 9% increase in Hispanics (adjusted odds ratio, 1.09; 95% CI, 1.05-1.14; P < .001) compared with whites. Fistula maturation for HD access for whites vs blacks vs Hispanics was 77.0% vs 76.3% vs 77.8% (P = .35). After adjusting for covariates, fistula maturation was higher for blacks (adjusted hazard ratio, 1.09; 95% CI, 1.06-1.13; P < .001) and Hispanics (adjusted hazard ratio, 1.13; 95% CI, 1.06-1.20; P < .001) compared with whites. There was no significant difference in prosthetic graft maturation for blacks and Hispanics compared with whites. Primary, primary-assisted, and secondary patency were highest for Hispanic and least for black autogenous fistula recipients. Primary, primary-assisted, and secondary patency was also highest for Hispanic patients who received prosthetic grafts. Prosthetic grafts were associated with a decrease in patency and patient survival compared with fistulas in all racial categories. Mortality was lower for blacks and Hispanics relative to white patients. Initiation of HD with a catheter and conversion to autogenous fistula was associated with decrease in patency and patient survival compared with initiation with a fistula in all racial groups.

CONCLUSIONS

Autogenous fistulas are associated with better patency and patient survival compared with prosthetic grafts for all races studied. The use of HD catheter before fistula placement is more prevalent in Hispanic and black patients and is associated with worse patency and patient survival irrespective of race. Fistula and graft patency is highest for Hispanic patients. Patient survival is higher for Hispanic and black patients relative to whites. These associations suggest potential benefit with initiation of HD via autogenous fistula and minimizing temporizing catheter use, irrespective of race.

Oral Sucrosomial® iron versus intravenous iron for recovering iron deficiency anaemia in ND-CKD patients: a cost- minimization analysis

BACKGROUND

Oral iron is recommended as first line treatment of anemia in non-dialysis chronic kidney disease (ND-CKD) patients. Sucrosomial® iron, a new generation oral iron with high absorption and bioavailability and a low incidence of side effects, has shown to be not inferior to intravenous (IV) iron in the replacement of iron deficiency anemia in patients with ND-CKD. Besides the clinical benefit, it is also important to determine the comparative total costs of oral versus IV iron administrations. The aim of this study was to perform a cost-minimization analysis of oral Sucrosomial iron, compared with IV iron gluconate from an Italian societal perspective.

METHODS

Cost analysis was performed on the 99 patients with ND-CKD and iron-deficiency anemia of the randomized trial by Pisani et al. Human and material resources utilization was recorded during each iron administration. According to study perspective, direct and indirect costs were considered. Costs for each resource unit were taken from official Italian sources. Probabilistic sensitivity analyses were carried out to test the robustness of the results.

RESULTS

The base case analysis showed an average cost/cycle per patient of € 111 for oral iron and € 1302 for IV iron. Thus, the potential saving was equal to € 1191 per patient/cycle. The sensitivity analysis showed that the most sensitive driver is the time loss by patient and caregivers for the therapy and related-care, followed by the minutes of nursing care and the number of kilometres travelled to reach the referral centre.

DISCUSSION

This study showed that oral Sucrosomial® iron could offer specific advantages in terms of potential savings, and allowed identifying some implications for future research. Such advantages still persist with the new single dose IV iron formulation available in the market, although to a lesser extent.

The Influence of Inflammation on Anemia in CKD Patients

Anemia is frequently observed in the course of chronic kidney disease (CKD) and it is associated with diminishing the quality of a patient’s life. It also enhances morbidity and mortality and hastens the CKD progression rate. Patients with CKD frequently suffer from a chronic inflammatory state which is related to a vast range of underlying factors. The results of studies have demonstrated that persistent inflammation may contribute to the variability in Hb levels and hyporesponsiveness to erythropoietin stimulating agents (ESA), which are frequently observed in CKD patients. The understanding of the impact of inflammatory cytokines on erythropoietin production and hepcidin synthesis will enable one to unravel the net of interactions of multiple factors involved in the pathogenesis of the anemia of chronic disease. It seems that anti-cytokine and anti-oxidative treatment strategies may be the future of pharmacological interventions aiming at the treatment of inflammation-associated hyporesponsiveness to ESA. The discovery of new therapeutic approaches towards the treatment of anemia in CKD patients has become highly awaited. The treatment of anemia with erythropoietin (EPO) was associated with great benefits for some patients but not all.

Impact of Intravenous Iron on Oxidative Stress and Mitochondrial Function in Experimental Chronic Kidney Disease

Background: Mitochondrial dysfunction is observed in chronic kidney disease (CKD). Iron deficiency anaemia (IDA), a common complication in CKD, is associated with poor clinical outcomes affecting mitochondrial function and exacerbating oxidative stress. Intravenous (iv) iron, that is used to treat anaemia, may lead to acute systemic oxidative stress. This study evaluated the impact of iv iron on mitochondrial function and oxidative stress. Methods: Uraemia was induced surgically in male Sprague-Dawley rats and studies were carried out 12 weeks later in two groups sham operated and uraemic (5/6 nephrectomy) rats not exposed to i.v. iron versus sham operated and uraemic rats with iv iron. Results: Induction of uraemia resulted in reduced iron availability (serum iron: 31.1 ± 1.8 versus 46.4 ± 1.4 µM), low total iron binding capacity (26.4 ± 0.7 versus 29.5 ± 0.8 µM), anaemia (haematocrit: 42.5 ± 3.0 versus 55.0 ± 3.0%), cardiac hypertrophy, reduced systemic glutathione peroxidase activity (1.12 ± 0.11 versus 1.48 ± 0.12 U/mL), tissue oxidative stress (oxidised glutathione: 0.50 ± 0.03 versus 0.36 ± 0.04 nmol/mg of tissue), renal mitochondrial dysfunction (proton/electron leak: 61.8 ± 8.0 versus 22.7 ± 5.77) and complex I respiration (134.6 ± 31.4 versus 267.6 ± 26.4 pmol/min/µg). Iron therapy had no effect on renal function and cardiac hypertrophy but improved anaemia and systemic glutathione peroxidase (GPx) activity. There was increased renal iron content and complex II and complex IV dysfunction. Conclusion: Iron therapy improved iron deficiency anaemia in CKD without significant impact on renal function or oxidant status.

Roxadustat for Anemia in Patients with Kidney Disease Not Receiving Dialysis

BACKGROUND

Roxadustat (FG-4592) is an oral inhibitor of hypoxia-inducible factor (HIF) prolyl hydroxylase that stimulates erythropoiesis and regulates iron metabolism. In phase 2 studies involving patients with chronic kidney disease, roxadustat increased levels of endogenous erythropoietin to within or near the physiologic range, along with increasing hemoglobin levels and improving iron homeostasis. Additional data are needed regarding the efficacy and safety of roxadustat for the treatment of anemia in patients with chronic kidney disease who are not undergoing dialysis.

METHODS

In this phase 3 trial conducted at 29 sites in China, we randomly assigned 154 patients with chronic kidney disease in a 2:1 ratio to receive roxadustat or placebo three times a week for 8 weeks in a double-blind manner. All the patients had a hemoglobin level of 7.0 to 10.0 g per deciliter at baseline. The randomized phase of the trial was followed by an 18-week open-label period in which all the patients received roxadustat; parenteral iron was withheld. The primary end point was the mean change from baseline in the hemoglobin level, averaged over weeks 7 through 9.

RESULTS

During the primary-analysis period, the mean (±SD) change from baseline in the hemoglobin level was an increase of 1.9±1.2 g per deciliter in the roxadustat group and a decrease of 0.4±0.8 g per deciliter in the placebo group (P<0.001). The mean reduction from baseline in the hepcidin level (associated with greater iron availability) was 56.14±63.40 ng per milliliter in the roxadustat group and 15.10±48.06 ng per milliliter in the placebo group. The reduction from baseline in the total cholesterol level was 40.6 mg per deciliter in the roxadustat group and 7.7 mg per deciliter in the placebo group. Hyperkalemia and metabolic acidosis occurred more frequently in the roxadustat group than in the placebo group. The efficacy of roxadustat in hemoglobin correction and maintenance was maintained during the 18-week open-label period.

CONCLUSIONS

In Chinese patients with chronic kidney disease who were not undergoing dialysis, those in the roxadustat group had a higher mean hemoglobin level than those in the placebo group after 8 weeks. During the 18-week open-label phase of the trial, roxadustat was associated with continued efficacy. (Funded by FibroGen and FibroGen [China] Medical Technology Development; ClinicalTrials.gov number, NCT02652819.).

Haemoglobin concentration and survival of haemodialysis patients before and after experiencing cardiovascular disease: a cohort study from Japanese dialysis outcomes and practice pattern study (J-DOPPS)

OBJECTIVES

Differences in the association of haemoglobin concentration with mortality or adverse cardiovascular events in haemodialysis patients before and after experiencing cardiovascular disease are unclear. We aimed to assess the influence of cardiovascular-comorbid condition on the association between haemoglobin concentration and mortality.

DESIGN

A prospective cohort study.

SETTING

The Dialysis Outcomes and Practice Patterns Study Dialysis in phases 2 to 4 (2002 to 2011), including 80 randomly selected dialysis facilities in Japan (J-DOPPS).

PARTICIPANTS

5515 adult haemodialysis patients.

PRIMARY AND SECONDARY OUTCOME MEASURES

Primary outcome was all-cause mortality. Cardiovascular mortality and adverse cardiovascular events were also evaluated. The association of these outcomes with haemoglobin concentration, categorised into six classes by 1.0 g/dL units, and cardiovascular-comorbid condition, treated as a time-dependent variable updated every 4 months, was evaluated. Adjusted hazard ratios (aHRs) were computed using a time-dependent Cox model with interaction test for cardiovascular comorbidity.

RESULTS

Over a median 2.0 years, 847 all-cause and 326 cardiovascular deaths, and 1000 adverse cardiovascular events occurred. Compared with haemoglobin 11.0 to 11.9 g/dL, the aHRs of mortality at the lowest range (<9.0 g/dL) were 1.29 (95% CI 0.95 to 1.76) and 2.11 (95% CI 1.47 to 3.06) in cardiovascular-comorbid and non-cardiovascular-comorbid patients, respectively (p=0.04 for cardiovascular-comorbid interaction), with increased cardiovascular mortality in both groups. At the second-lowest range (9.0 to 9.9 g/dL), mortality was increased only in non-cardiovascular-comorbid patients. Respective risks for mortality and adverse cardiovascular events at the second-highest range (12.0 to 12.9 g/dL) were non-significant but increased in both groups, while adverse cardiovascular events were increased at the highest range (≥13.0 g/dL) in non-cardiovascular-comorbid patients.

CONCLUSIONS

The association of low haemoglobin concentration with all-cause mortality differed between haemodialysis patients with and without cardiovascular comorbidity. Cardiovascular-comorbid condition should be considered when the association of haemoglobin concentration with mortality is addressed.

Increased mortality in haemodialysis patients administered high doses of erythropoiesis-stimulating agents: a propensity score-matched analysis

Background

Erythropoiesis-stimulating agents (ESAs) are widely used to treat anaemia in patients with chronic kidney disease. The issue of ESA safety has been raised in multiple studies, with correlates derived for elevated cancer incidence and mortality. Whether these associations are related to ESA dose or the typology of the patient remains obscure.

Methods

A multicentre, observational retrospective propensity score-matched study was designed to analyse the effects of weekly ESA dose in 1679 incident haemodialysis (HD) patients. ESA administration was according to standard medical practice. Patients were grouped as quintiles, according to ESA dose, in order to compare mortality and hospitalization data. Using propensity score matching (PSM), we defined two groups of 324 patients receiving weekly threshold ESA doses of either > or ≤8000 IU.

Results

Kaplan-Meier survival curves indicated significant increases in the risk of mortality in patients administered with high doses of ESAs (>8127.4 IU/week). Multivariate Cox models identified a high ESA dose as an independent predictor for all-cause and cardiovascular (CV) mortality. Moreover, logistic regression models identified high ESA doses as an independent predictor for all-cause, CV and infectious hospitalization. PSM analyses confirmed that weekly ESA doses of >8000 IU constitute an independent predictor of all-cause mortality and hospitalization, even though the adjusted cohort displayed the same demographic features, inflammatory profile, clinical HD parameters and haemoglobin levels.

Conclusions

Our data suggest that ESA doses of >8000 IU/week are associated with an increased risk of all-cause mortality and hospitalization in HD patients.

Usefulness of mid-week hemoglobin measurement for anemia management in patients undergoing hemodialysis: a retrospective cohort study

Background

Short-term hemoglobin (Hb) variability related to volume status is observed in chronic kidney disease (CKD) patients receiving hemodialysis (HD). Given the lack of studies regarding outcomes according to the day of Hb sampling, the existing guidelines do not strongly recommend regarding measurement timing. Pre-dialysis mid-week sampling (Wednesday and Thursday) is preferable to minimize short-term Hb variability, although numerous HD centers perform early-week sampling (Monday and Tuesday). The different measurement days may influence the prescribed dose of erythropoiesis-stimulating agent (ESA) and related patient outcomes. We investigated changes in Hb levels and ESA doses according to the Hb measurement day among HD patients.

Methods

Starting September 2013, the day for pre-dialysis Hb measurement at the Asan Medical Center was changed from early-week days to mid-week days. This single-center retrospective study evaluated medical records of 92 patients who received maintenance HD between September 2012 and August 2014.

Results

There was no significant difference in the mean Hb levels between early-week days and mid-week days (10.71 ± 0.06 g/dL vs. 10.78 ± 0.47 g/dL, p = 0.105). However, the mean doses of darbepoetin-α on early-week days were higher than those on mid-week days (175.4 ± 72.5 μg/month vs. 163.7 ± 83.6 μg/month, p = 0.022). The mean doses of intravenous iron hydroxide sucrose for early-week measurements were also higher than those for mid-week measurements (623.0 ± 489.0 mg/year vs. 447.0 ± 505.2 mg/year, p = 0.001). The mean interdialytic weight gains were 2.81 ± 0.82 kg on early-week days and 1.99 ± 0.61 kg on mid-week days (p < 0.001).

Conclusions

Compared with early-week measurements, mid-week pre-dialysis Hb measurements were significantly associated with lower ESA doses without a change in Hb levels.

Heme, Heme Oxygenase, and Endoplasmic Reticulum Stress-A New Insight into the Pathophysiology of Vascular Diseases

The prevalence of vascular disorders continues to rise worldwide. Parallel with that, new pathophysiological pathways have been discovered, providing possible remedies for prevention and therapy in vascular diseases. Growing evidence suggests that endoplasmic reticulum (ER) stress is involved in a number of vasculopathies, including atherosclerosis, vascular brain events, and diabetes. Heme, which is released from hemoglobin or other heme proteins, triggers various pathophysiological consequence, including heme stress as well as ER stress. The potentially toxic free heme is converted by heme oxygenases (HOs) into carbon monoxide (CO), iron, and biliverdin (BV), the latter of which is reduced to bilirubin (BR). Redox-active iron is oxidized and stored by ferritin, an iron sequestering protein which exhibits ferroxidase activity. In recent years, CO, BV, and BR have been shown to control cellular processes such as inflammation, apoptosis, and antioxidant defense. This review covers our current knowledge about how heme induced endoplasmic reticulum stress (HIERS) participates in the pathogenesis of vascular disorders and highlights recent discoveries in the molecular mechanisms of HO-mediated cytoprotection in heme stress and ER stress, as well as crosstalk between ER stress and HO-1. Furthermore, we focus on the translational potential of HIERS and heme oxygenase-1 (HO-1) in atherosclerosis, diabetes mellitus, and brain hemorrhage.