The development of anemia is associated to poor prognosis in NKF/KDOQI stage 3 chronic kidney disease

Prognostic factors and validation of the histologic chronicity score for C3 glomerulopathy: a registry analysis

Background

Data on the prognostic factors for C3 glomerulopathy (C3G) are limited, and validation of the new C3G histologic index (C3G-HI) in different settings is still needed. We aimed to evaluate the chronicity score of C3G-HI and probable prognostic factors in our population.

Methods

In this registry study, 74 patients from 20 centers with adequate follow-up data were included. Total chronicity score (TCS) was calculated according to percentages of glomerulosclerosis, interstitial fibrosis, tubular atrophy, and presence of arterio- and arteriolosclerosis. Primary composite outcome was defined as doubling of serum creatinine from baseline, undergoing dialysis or transplantation, development of stage 5 chronic kidney disease, or death.

Results

Median age was 34 [interquartile range (IQR) 24-46] years, and 39 patients (52.7%) were male. Median follow-up duration was 36 (IQR 12-60) months, and median TCS was 3 (IQR 1-5). Overall, 19 patients (25.7%) experienced primary composite outcome. Multivariate Cox regression model showed that only hemoglobin [adjusted HR (aHR) 0.67, 95% confidence interval 0.46-0.97, P = .035] predicted primary composite outcome, and TCS fell short of the statistical significance (aHR 1.26, 0.97-1.64, P = .08). Receiver operating characteristic analysis demonstrated that TCS showed an area under the curve value of 0.68 (0.56-0.78, P = .028) in discriminating primary composite outcome at 3 years, and 3-year kidney survival was lower in patients with TCS ≥4 (72.4%) compared with TCS <4 (91.1%) in Kaplan-Meier analysis (P = .036).

Conclusions

Low hemoglobin levels predicted dismal outcomes in patients with C3G. TCS ≥4 was associated with a worse 3-year kidney survival, which validated the 3-year prognostic value of the TCS of C3G-HI in our population.

Effectiveness of Lactoferrin in the Treatment of Anemia in Chronic Kidney Disease: A Single-Center Pilot Study

Background

Anemia occurs in majority of patients with chronic kidney disease despite adequate dialysis and iron replete status. This study was done to evaluate the effects of lactoferrin with or without iron supplementation for the treatment of anemia in patients with chronic kidney disease (CKD).

Materials and Methods

In this prospective, observational, single-center, single-arm pilot study, adult patients aged >18 years, having stage 5 CKD (estimated glomerular filtration rate [eGFR] <15 ml/min/1.73 m2), and who had anemia (hemoglobin [Hb] <10 g/dl; transferrin saturation [Tsat] >20%) were included. Patients were treated with 100 mg of oral lactoferrin twice a day for one month with or without iron supplementation. Patients had been on stable erythropoietin doses for ≥1 month prior to inclusion in the study. We report on the improvement in Hb levels and effect on inflammatory markers from baseline at four weeks.

Results

A total of 46 CKD patients having anemia were included. Patients had a mean age of 39.3 years, and a majority were men (69.6%). Improvement in the mean (SD) Hb level (g/dl) was observed from baseline (8.18 [1.19]) to Week 2 (8.54 [1.57]), which attained significance at Week 4 (8.96 [1.93]; P < 0.001; mean difference: -0.76; 95% confidence interval [CI]: -1.291 to - 0.2383). The improvement in Hb was higher in women than in men (P = 0.48) and in patients receiving lactoferrin with iron supplementation than in those receiving lactoferrin alone (P = 0.14). There was a non-significant decrease in the erythrocyte sedimentation rate (P = 0.14) and a non-significant increase in C-reactive protein (P = 0.54) level.

Conclusion

Oral lactoferrin therapy was effective in improving hemoglobin levels in patients with advanced CKD and anemia. The effects of lactoferrin therapy on inflammatory markers remain uncertain.

The estimated mediating roles of anemia-related variables in the association between kidney function and mortality: a National Health and Nutrition Examination Survey (NHANES) study

Anemia is a common complication of chronic kidney disease (CKD), impacting long-term outcomes such as mortality and morbidity. Analyzing NHANES data from 1999 through 2016 for adults aged ≥ 20 years, we assessed the mediating effects of anemia biomarkers (hemoglobin, hematocrit, red cell distribution width [RDW], and mean corpuscular hemoglobin concentration [MCHC]) on CKD-related outcomes by using hazard ratios from a biomarker-adjusted model. Of 44,099 participants, 7463 experienced all-cause death. Cox proportional hazard models revealed a higher all-cause mortality risk in the > 45 years and CKD groups than in the early CKD group. Hemoglobin, hematocrit and MCHC were inversely related to all-cause mortality; RDW was related to mortality. Single mediation analysis showed greater mediating effects of anemia indicators on CKD and mortality in the elderly (> 65 years) population than those in the general population. In the multimediation analysis, the combined mediating effect of anemia was higher in the CKD population than in the general population. This study showed a proportional increase in the mediating effect of anemia with CKD stage, suggesting potential therapeutic avenues. However, further exploration of other mediating factors on kidney outcomes is necessary.

Effect of SGLT2 inhibitors on anemia and their possible clinical implications

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have demonstrated cardiovascular and renal benefits in patients with type 2 diabetes mellitus, heart failure, or chronic kidney disease. Since the first studies with these drugs, an initial increase in hemoglobin/hematocrit levels was observed, which was attributed to an increase in hemoconcentration associated with its diuretic effect, although it was early appearent that these drugs increased erythropoietin levels and erythropoiesis, and improved iron metabolism. Mediation studies found that the increase in hemoglobin was strongly associated with the cardiorenal benefits of these drugs. In this review, we discuss the mechanisms for improving erythropoiesis and the implication of the increase in hemoglobin on the cardiorenal prognostic benefit of these drugs.

Specific patterns and potential risk factors to predict 3-year risk of death among non-cancer patients with advanced chronic kidney disease by machine learning

Chronic kidney disease (CKD) is a major public health concern. But there are limited machine learning studies on non-cancer patients with advanced CKD, and the results of machine learning studies on cancer patients with CKD may not apply directly on non-cancer patients. We aimed to conduct a comprehensive investigation of risk factors for a 3-year risk of death among non-cancer advanced CKD patients with an estimated glomerular filtration rate < 60.0 mL/min/1.73m2 by several machine learning algorithms. In this retrospective cohort study, we collected data from in-hospital and emergency care patients from 2 hospitals in Taiwan from 2009 to 2019, including their international classification of disease at admission and laboratory data from the hospital's electronic medical records (EMRs). Several machine learning algorithms were used to analyze the potential impact and degree of influence of each factor on mortality and survival. Data from 2 hospitals in northern Taiwan were collected with 6565 enrolled patients. After data cleaning, 26 risk factors and approximately 3887 advanced CKD patients from Shuang Ho Hospital were used as the training set. The validation set contained 2299 patients from Taipei Medical University Hospital. Predictive variables, such as albumin, PT-INR, and age, were the top 3 significant risk factors with paramount influence on mortality prediction. In the receiver operating characteristic curve, the random forest had the highest values for accuracy above 0.80. MLP, and Adaboost had better performance on sensitivity and F1-score compared to other methods. Additionally, SVM with linear kernel function had the highest specificity of 0.9983, while its sensitivity and F1-score were poor. Logistic regression had the best performance, with an area under the curve of 0.8527. Evaluating Taiwanese advanced CKD patients' EMRs could provide physicians with a good approximation of the patients' 3-year risk of death by machine learning algorithms.

Possible sarcopenia and risk of chronic kidney disease: a four-year follow-up study and Mendelian randomization analysis

INTRODUCTION

Chronic kidney disease (CKD) is a common risk factor for sarcopenia. However, whether sarcopenia increases the risk of CKD remains unclear. To investigate the longitudinal and causal associations between possible sarcopenia and CKD, this study was performed.

METHODS

Possible sarcopenia was defined according to the Asian Working Group for Sarcopenia in 2019. Participants aged ≥ 40 years were recruited from the baseline survey of the China Health and Retirement Longitudinal Study and followed up for four years. Binary logistic regression was used to evaluate the cross-sectional and longitudinal associations between possible sarcopenia, low muscle strength, low physical performance and CKD. Propensity score matching was used to balance the intergroup differences. Subgroup and interactive analyses were adopted to identify potential interactive effects. Mendelian Randomization analysis was used to assess the causal association between appendicular lean mass (ALM) and CKD.

RESULTS

After data cleansing, a total of 7296 participants were included in the baseline survey. In the cross-sectional analyses, the odds ratios (ORs) of prevalent CKD were 1.50 (95% CI = 1.23-1.84, p < 0.001) for possible sarcopenia, 1.37 (95% CI = 1.10-1.70, p < 0.01) for low muscle strength and 1.42 (95% CI = 1.16-1.74, p < 0.001) for low physical performance in the full models. No significant interaction effects of covariates were detected (all P for interaction > 0.05). After four years of follow-up, an increased risk of incident CKD was also observed in participants with possible sarcopenia (OR = 1.66, 95% CI = 1.13-2.44, p = 0.010) and low physical performance (OR = 1.69, 95% CI = 1.16-2.45, p = 0.006), but not in participants with low muscle strength (OR = 1.19, 95% CI = 0.75-1.88, p = 0.469). In the Mendelian Randomization analysis, the inverse variance weighted estimator showed that a 1-standard deviation increase of genetically predicted ALM was associated with a lower risk of CKD (OR = 0.92, 95% CI = 0.85-0.99, p = 0.035). All the sensitivity analyses supported the main findings.

CONCLUSIONS

Possible sarcopenia is an independent risk factor for CKD and may serve as a predictor of CKD for early identification and intervention.

Budget impact analysis on the Italian healthcare system of roxadustat for the treatment of anemia due to chronic kidney disease

Objective: The aim of this study was to evaluate the economic consequences of the introduction of roxadustat on the market as treatment for chronic kidney disease (CKD)-related anaemia in Italy. Method: A budget impact model was developed to assess the economic impact of the introduction of roxadustat for the management of patient with CKD-related anaemia. The analysis was conducted considering National Health Service (NHS) perspective and three years’ time horizon. Eligible population for the treatment with roxadustat was estimated through published literature and clinicians’ support. Direct healthcare costs included drug acquisition (list prices for base case) and administration costs, monitoring costs, cost per blood transfusion, costs related to the management of adverse events and dialysis costs. Results: The model estimated a three years expenditure associated with the management of patients with CKD-related incident anaemia in Italy of about € 260 and € 44.6 million for non-dialysis dependent (NDD) and dialysis-dependent (DD) patients respectively. The introduction of roxadustat on the market could generate a reduction in the expenditure related to the iron supplementation both for NDD and for DD patients (−€ 397,305 and −€ 50,135 over three years of the analysis, respectively) and a reduction in the pharmaceutical expenditure for NDD patients (−€ 2.3 million, −€ 7.5 million and −€ 13 million at first, second and third year of the analysis). Overall, the introduction of roxadustat could generate a saving for NHS approximately equal to € 2.3, € 7.5 and € 13 million at first, second and third year of the analysis. Conclusion: The introduction of roxadustat could generate a reduction in the expenditure for the management of patients with CKD anaemia. A scenario analysis which used tender prices for ESAs and hypothesis of confidential discount for roxadustat showed that the saving for NHS will be kept if roxadustat’s discount is greater than 60.3%.

Quantitative systems pharmacology model of erythropoiesis to simulate therapies targeting anemia due to chronic kidney disease

Anemia induced by chronic kidney disease (CKD) has multiple underlying mechanistic causes and generally worsens as CKD progresses. Erythropoietin (EPO) is a key endogenous protein which increases the number of erythrocyte progenitors that mature into red blood cells that carry hemoglobin (Hb). Recombinant human erythropoietin (rHuEPO) in its native and re-engineered forms is used as a therapeutic to alleviate CKD-induced anemia by stimulating erythropoiesis. However, due to safety risks associated with erythropoiesis-stimulating agents (ESAs), a new class of drugs, prolyl hydroxylase inhibitors (PHIs), has been developed. Instead of administering exogenous EPO, PHIs facilitate the accumulation of HIF-α, which results in the increased production of endogenous EPO. Clinical trials for ESAs and PHIs generally involve balancing decisions related to safety and efficacy by carefully evaluating the criteria for patient selection and adaptive trial design. To enable such decisions, we developed a quantitative systems pharmacology (QSP) model of erythropoiesis which captures key aspects of physiology and its disruption in CKD. Furthermore, CKD virtual populations of varying severities were developed, calibrated, and validated against public data. Such a model can be used to simulate alternative trial protocols while designing phase 3 clinical trials, as well as an asset for reverse translation in understanding emerging clinical data.

Combined use of handgrip strength and hemoglobin as markers of undernutrition in patients with stage 3-5 chronic kidney disease

BACKGROUND AND AIMS

The early identification of undernourished patients with CKD could help instating appropriate nutritional intervention before the full development of the threatening condition known as Protein Energy Wasting (PEW). Handgrip strength (HGS) and blood hemoglobin (Hb) concentration are two parameters considered representative of nutritional status but not included among the criteria for PEW diagnosis. In the present work we investigated whether they could help identifying CKD patients at risk of undernutrition.

METHODS AND RESULTS

We performed a two-step cluster analysis to classify a cohort of 71 stage 3-5 CKD patients, none of which with PEW, according to their Hb concentration and dominant-hand HGS. Two clusters were finely separated using this method. When we compared the two groups for main body composition and nutritional variables by using t-test statistics or Mann-Whitney test, as appropriate, we found significant differences in PhA, ECW/TBW, ASMI, serum iron. Then we stratified our population by gender and performed cluster analysis as well. PhA, ECW/TBW were still significantly different in the two clusters both in M and in F, while serum iron concentration only in males and ASMI only in females.

CONCLUSION

These results suggest that either in male than in female Hb concentration and HGS may distinguish two subgroups of CKD patients with different nutritional status and disease severity. Patient belonging to either of these cluster can be easily identified by using the HGS/Hb ratio which represents the HGS normalized per gr Hb.

Poor recognition and undertreatment of anemia in patients with chronic kidney disease managed in primary care

BACKGROUND

Anemia is a common complication of chronic kidney disease (CKD), but limited awareness and treatment options may hinder its management among CKD patients followed in primary care.

METHODS

We evaluated adults with CKD stages 3-5 attending primary care in Stockholm, Sweden, 2012-2018. We assessed the incidence of anemia, clinical reactions, and association with subsequent major adverse cardiovascular events (MACE) and death.

RESULTS

We identified 45,637 patients with CKD stages 3-5 free from anemia (mean age 78 years; 64% females; 79% CKD stage 3b). During a median follow-up of 2.4 years, 26% of patients developed anemia, and 10.4% developed severe anemia (hemoglobin <10 g/dL). Within 6 months from the anemia event, iron tests were infrequent; ferritin and transferrin saturation were tested in 27% and 11% of anemia cases, respectively, and 49% and 24% of severe anemia cases. Few patients were recognized with a clinical diagnosis (15% of anemia cases; 68% of severe anemias). Only 19% of patients with anemia received treatment, primarily iron (10%) and blood transfusions (7%); erythropoietin-stimulating agent use was anecdotal (∼1%). Treatment rates for severe anemia were higher, but 43% of patients still failed to receive treatment. Developing anemia was associated with a higher risk of MACE and death.

CONCLUSION

Anemia was common and associated with adverse outcomes among patients with CKD stages 3-5 managed in primary care. Iron stores were infrequently tested, and a large proportion of patients with anemia remained untreated/under-recognized.

Epidemiology and treatment of renal anaemia in Spain: RIKAS retrospective study

BACKGROUND AND OBJECTIVE

Studies on the prevalence of anaemia in chronic kidney disease in adults not on dialysis (CKD-ND) and in dialysis programmes (CKD-D) in Spain are not recent or focus on certain subgroups. The aim of this study was to know the epidemiology and current treatment patterns of anaemia associated with CKD in Spain.

MATERIALS AND METHODS

Multicentre, non-interventional, retrospective study with CKD-ND stage 3a-5 and CKD-D patients treated in Spain between 2015 and 2017 (RIKAS study).

RESULTS

The prevalence of anaemia in CKD-ND and CKD-D in 2015 was 33.8% and 91.5%, respectively, with similar results during 2016-2017. The prevalence of systemic inflammation in anaemic patients (18.1% and 51.8% for CKD-ND and CKD-D, respectively) was higher, especially in those treated with erythropoiesis-stimulating agents (ESA), compared to the general population with CKD-ND. After 12 months of follow-up, mean ferritin and transferrin saturation index (TSI) values in anaemic patients with CKD-ND were 187.1 ng/mL and 22.2%, respectively, while in CKD-D were 254.6 ng/mL and 20.2%. In ESA-treated patients, mean values were 190.6 ng/mL and 22.0% in ND-CKD, and 255.0 ng/mL and 20.2% in D-CKD.

CONCLUSIONS

The prevalence of anaemia and inflammation increased with the disease severity, being higher in D-CKD. Iron parameters in anaemic patients treated or not with ESA are insufficient according to the guidelines, so there is room for improvement in the treatment of anaemia associated with CKD.

Evaluating the baseline hemoglobin, albumin, lymphocyte, and platelet (HALP) score in the United States adult population and comorbidities: an analysis of the NHANES

Introduction

As a composite immunonutritional biomarker, the Hemoglobin, Albumin, Lymphocyte, Platelet (HALP) score has shown promise in assessing a patient's overall health status by integrating several routinely collected laboratory indicators. This biomarker has been examined in many different populations of patients and disease states (i.e., cancer), but an integrated, universal rubric using standardized thresholds has not thus far been developed. Pre-existing large population-based databases represent an ideal source to examine the distribution of HALP and the influence of diverse health statuses on this score.

Methods

We conducted a cross-sectional study using data from the National Health and Nutrition Examination Survey (NHANES) between 2017-2020, evaluating 8,245 participants across numerous demographic, socioeconomic, and health-related variables. Univariate and multivariate linear regression analyses assessed the associations between HALP scores and these factors.

Results

Our findings revealed significant associations between HALP scores and various demographic, socioeconomic, and health conditions. The median HALP score among the representative population was 49.0, with varying median scores across different groups and normal reference ranges for males and females. Multivariate regression analysis showed that anemia treatment, age over 65 years, weak/failing kidneys, and cancer were independent risk factors associated with lower HALP scores. Male participants demonstrated higher HALP scores than female participants, and age was inversely related to HALP. Moreover, HALP scores were negatively associated with the number of comorbidities.

Conclusion/discussion

This study set out to explore the HALP score from a population-based perspective, uncovering notable associations that offer vital insights into the score's clinical relevance and future applications. By determining a median HALP score of 49.0 and normal reference ranges within our diverse, representative sample, we establish a robust foundation for researchers to refine optimal HALP applications and thresholds. Considering the growing focus on personalized medicine, HALP holds promise as a prognostic tool, enabling clinicians to comprehend their patients' immunonutritional status better and deliver customized care.

Anemia and its predictors among chronic kidney disease patients in Sub-Saharan African countries: A systematic review and meta-analysis

INTRODUCTION

Anemia is a serious complication of chronic kidney disease (CKD) with a significant adverse outcome on the burden and progression of the disease. Hence, the study intended to assess the pooled prevalence of anemia and its predictors among CKD patients in Sub-Saharan African nations.

METHODS

To identify the relevant studies systematic searches were carried out in Medline, EMBASE, HINARI, Google Scholar, Science Direct, and Cochrane Library. From selected studies, data were taken out with a standardized data extraction format prepared in Microsoft Excel. Inverse variance (I2) tests were employed to evaluate the heterogeneity across the included studies. Due to substantial heterogeneity among the studies, a random-effects meta-analysis technique was employed to estimate the pooled prevalence of anemia. Subgroup analysis, sensitivity analysis, and meta-regression analysis were carried out to search the possible bases of heterogeneity. Funnel plot symmetry, Begg's test, and Egger's regression test were employed to assess the existence of publication bias. In addition, factors associated with anemia among CKD patients were examined. All statistical analyses were carried out with STATA™ Version 14 software.

RESULTS

A total of 25 studies with 5042 study participants were considered in this study. The pooled prevalence of anemia among CKD patients was estimated to be 59.15% (95% CI, 50.02-68.27) with a substantial level of heterogeneity as evidenced by I2 statistics (I2 = 98.1%; p < 0.001). Stage of CKD (3-5) (pooled odds ratio (POR) = 5.33, 95% CI:4.20-6.76), presence of diabetes mellitus (POR = 1.75, 95% CI: 1.10-2.78), hemodialysis history (POR = 3.06, 95% CI: 1.63-5.73), and female sex (POR = 2.50, 95% CI: 1.76-3.55) were significantly related with anemia.

CONCLUSIONS

More than half of CKD patients were suffering from anemia. Stage of CKD, presence of DM, hemodialysis history, and being female sex were factors associated with anemia among CKD patients.

Real-Life Anemia Management Among Patients with Non-Dialysis-Dependent Chronic Kidney Disease in Three European Countries

Background

Anemia is prevalent among patients with chronic kidney disease (CKD), yet current evidence indicates that treatment may not adhere to Kidney Disease: Improving Global Outcomes (KDIGO) guidelines. We aimed to document the management of patients with non-dialysis-dependent (NDD)-CKD receiving erythropoiesis-stimulating agent (ESA) therapy in Europe.

Methods

This retrospective, observational study extracted information from medical records in Germany, Spain, and the UK. Eligible patients were adults with NDD-CKD stages 3b-5 who initiated ESA therapy for anemia between January and December 2015. Anemia was defined as hemoglobin (Hb) <13.0 g/dL (males) or <12.0 g/dL (females). Data regarding ESA treatment, treatment response, concomitant iron therapy and blood transfusions were extracted up to 24 months post-ESA initiation, and data on CKD progression until abstraction date.

Results

Eight hundred and forty-eight medical records were abstracted. Approximately 40% received no iron therapy prior to ESA initiation. At ESA initiation, mean ± standard deviation Hb level was 9.8 ± 1.0 g/dL. Most patients received darbepoetin alfa, and switching between ESAs was rare (8.5% of patients). Concomitant intravenous and oral iron therapy was prescribed for 36% and 42% of patients, respectively, during initial ESA therapy. Mean Hb levels reached the target level (10-12 g/dL) within 3-6 months of ESA initiation. Hb, transferrin saturation, and ferritin levels were infrequently monitored from 3 months post-ESA initiation. Rates of blood transfusion, dialysis, and diagnosis of end-stage renal disease were 16.4%, 19.3%, and 24.6%, respectively. Rates of kidney transplant and death were 4.8% and 8.8%, respectively.

Conclusion

Among ESA-treated patients, ESA initiation was in accordance with KDIGO guidelines, but subsequent monitoring of Hb and iron deficiency were suboptimal.

The effect of anemia on the severity and prognosis of patients with acute pancreatitis: A single-center retrospective study

Anemia was a risk factor for a worse prognosis of many diseases. This study aims to investigate the relationship between anemia and the severity and prognosis of acute pancreatitis (AP). Inpatients hospitalized at the First Affiliated Hospital of Guangdong Pharmaceutical University with a primary diagnosis of AP between 1st July 2016 to 31st December 2020 were enrolled. Subsequently, disease severity, the incidence of complications, and the prognosis of patients with AP were compared between the anemic group and the non-anemic group. A total of 282 patients with acute pancreatitis were enrolled; 68.43% of them were also diagnosed with anemia. Notably, these patients had more severe disease (higher RANSON, acute physiologic assessment and chronic health evaluation-II, bedside index for severity in acute pancreatitis, and multiple organ dysfunction syndrome scores); higher incidence of organ failure (acute kidney injury [AKI] and acute heart failure); worse prognosis (higher incidence of vasoactive and diuretic agent use, longer hospital stays, and higher hospital costs) compared to that of patients without anemia (all P < .05). After adjusting for potential confounders, acute physiologic assessment and chronic health evaluation-II, bedside index for severity in acute pancreatitis, multiple organ dysfunction syndrome scores, hospital stay, and hospital costs in anemic patients were higher than those in non-anemic patients; besides, the incidence of AKI and using a diuretic agent in anemic patients was 6.645 and 4.053 times that of non-anemic patients in AP, respectively (all P < .05). Acute pancreatitis patients with anemia have more disease severity, higher incidence of AKI, and worse prognosis compared to those without anemia.

Association of anaemia with long-term mortality among patients with hypertensive crisis in the emergency department

BACKGROUND

Anaemia is frequent in patients with cardiovascular disease and is significantly associated with poor prognosis. However, the prognostic significance of anaemia in hypertensive crisis remains unknown. We conducted this study to determine whether anaemia is a risk factor for all-cause mortality in patients with hypertensive crisis visiting the emergency department (ED).

METHODS

This retrospective study included patients who visited the ED between 2016 and 2019 for hypertensive crisis, which was defined as systolic blood pressure ≥180 mmHg or diastolic blood pressure ≥110 mmHg. A total of 5,512 patients whose serum haemoglobin levels were checked were included in this study and were classified into three groups according to their serum haemoglobin levels at admission to the ED: moderate/severe anaemia (haemoglobin <11 g/dL), mild anaemia (haemoglobin 11 to <13 g/dL in men and 11 to <12 g/dL in women), and non-anaemia (haemoglobin ≥13 g/dL in men and ≥12 g/dL in women).

RESULTS

Among 5,512 patients, 665 (12.1%) and 668 (12.1%) were classified into the moderate/severe anaemia and mild anaemia groups, respectively. The three-year all-cause mortality rates in the moderate/severe anaemia, mild anaemia, and non-anaemia groups were 46.0, 29.2, and 12.0%, respectively. After accounting for relevant covariates, patients with moderate/severe anaemia group (hazard ratio [HR], 2.15; 95% confidence interval [CI], 1.75-2.64) and mild anaemia group (HR, 1.32; 95% CI, 1.07-1.63) had a higher risk of 3-year all-cause mortality than the non-anaemia group.

CONCLUSION

Anaemia is independently associated with 3-year all-cause mortality in patients with hypertensive crisis. A comprehensive therapeutic approach through more in-depth examination and close follow up are required for patients with hypertensive crisis with anaemia.KEY MESSAGESAnaemia is independently associated with 3-year all-cause mortality in patients with hypertensive crisis.A comprehensive therapeutic approach through more in-depth examination and close follow up are required for patients with hypertensive crisis with anaemia.

The Efficacy and Safety of Roxadustat for Anemia in Patients With Chronic Kidney Disease: A Meta-Analysis

Background: Chronic kidney disease (CKD) is a global public health problem, and anemia is a common complication in CKD patients. Roxadustat (FG-4592) is an oral hypoxia-inducible factor (HIF) stabilizer. Roxadustat has been shown in studies to keep up with and increase hemoglobin better than placebo or erythropoietin. The purpose of this meta-analysis was to assess the efficacy and safety of roxadustat.

Methods: We searched CBM, CNKI, VIP, Wanfang Database, PubMed, Cochrane Library, Embase, and Web of Science for randomized controlled trials of roxadustat for the treatment of anemia in CKD patients. The papers were screened using rigorous criteria and their quality was assessed using the Cochrane 5.1.0 assessment manual for randomized controlled trials (RCTs). RevMan 5.3 was used to extract and synthesize data for meta-analysis.

Results: There were 8 RCTs (7 articles) in all, and 1,364 patients with chronic kidney disease anemia were involved. The overall quality of the studies included was satisfactory. The meta-analysis findings revealed that roxadustat can considerably enhance hemoglobin, transferrin, and total iron binding capacity (TIBC) in both dialysis-dependent (DD) and non-dialysis-dependent (NDD) patients: Hemoglobin (Hb): DD: [SMD = 0.23, 95% CI (0.01, 0.44), p = 0.04], NDD: [SMD = 2.08, 95% CI (1.23, 2.93) p < 0.000001]; transferrin: DD: [SMD = 0.78, 95% CI (0.24, 1.32), p = 0.004], NDD: [SMD = 1.37, 95% CI (0.76, 1.98), p < 0.0001]; TIBC: DD [SMD = 0.97, 95% CI (0.64, 1.29), p < 0.00001], NDD [SMD = 1.34, 95% CI (0.9, 1.78), p < 0.00001]. After roxadustat therapy, patients’ serum iron levels were considerably higher in the dialysis group than in the control group, but there was no significant change in the NDD group [SMD = 0.42, 95% CI (0.27, 0.57), p < 0.00001]. In the NDD group, hepcidin, ferritin, and transferrin saturation (TSAT) were significantly reduced after roxadustat treatment: Hepcidin [SMD = −1.59, 95% CI (−2.69, −0.49), p = 0.005], ferritin [SMD = −0.51, 95% CI (−0.72, 0.3) p < 0.00001], TSAT [SMD = −0.41, 95% CI (−0.62, 0.2), p < 0.0001]. In terms of safety, adverse events (AE) [SMD = 1.08, 95% CI (0.98, 1.18) p = 0.11] and serious adverse events (SAE) [SMD = 1.32, 95% CI (0.97, 1.9) p = 0.08] were not significantly different between the two groups.

Conclusion: Roxadustat can improve anemia in NDD patients with chronic kidney disease, and its short-term safety was comparable to that of the comparison group.

New-Onset Anemia and Associated Risk of ESKD and Death in Non-Dialysis CKD Patients: A Multi-Cohort Observational Study

Background

Anemia is a common complication of chronic kidney disease (CKD), but its incidence in nephrology settings is poorly investigated. Similarly, the risks of adverse outcomes associated with new-onset anemia are not known.

Methods

We performed a pooled analysis of three observational cohort studies including 1031 non-anemic CKD patients with eGFR <60 mL/min/1.73 m² regularly followed in renal clinics. We estimated the incidence of mild anemia (hemoglobin 11–12 g/dL in women and 11–13 g/dL in men) and severe anemia (hemoglobin <11 g/dL or use of erythropoiesis-stimulating agents) during a 3-year follow-up period. Thereafter we estimated the risk of end-stage kidney disease (ESKD) and all-cause death associated with new-onset mild and severe anemia.

Results

The mean age was 63 ± 14 years, 60% were men and 20% had diabetes. The mean estimated glomerular filtration rate (eGFR) was 37 ± 13 mL/min/1.73 m² and the median proteinuria was 0.4 g/day [interquartile range (IQR) 0.1–1.1]. The incidence of mild and severe anemia was 13.7/100 patients-year and 6.2/100 patients-year, respectively. Basal predictors of either mild or severe anemia were diabetes, lower hemoglobin, higher serum phosphate, eGFR <30 mL/min/1.73 m² and proteinuria >0.50 g/day. Male sex, moderate CKD (eGFR 30–44 mL/min/1.73 m²) and moderate proteinuria (0.15–0.50 g/day) predicted only mild anemia. The incidence of anemia increased progressively with CKD stages (from 8.77 to 76.59/100 patients-year) and the proteinuria category (from 13.99 to 25.02/100 patients-year). During a median follow-up of 3.1 years, 232 patients reached ESKD and 135 died. Compared with non-anemic patients, mild anemia was associated with a higher adjusted risk of ESKD {hazard ratio [HR] 1.42 [95% confidence interval (CI) 1.02–1.98]} and all-cause death [HR 1.55 (95% CI 1.04–2.32)]. Severe anemia was associated with an even higher risk of ESKD [HR 1.73 (95% CI 1.20–2.51)] and death [HR 1.83 (95% CI 1.05–3.19)].

Conclusions

New-onset anemia is frequent, particularly in patients with more severe renal damage and in those with diabetes mellitus. The occurrence of anemia, even of a mild degree, is associated with mortality risk and faster progression towards ESKD.

Challenging patient phenotypes in the management of anaemia of chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is often complicated by anaemia, which is associated with disease progression and increased hospital visits, decreased quality of life, and increased mortality.

METHODS

A comprehensive literature search of English language peer-reviewed articles in PubMed/MedLine published between 1998 and 2020 related to the treatment of anaemia of CKD was conducted. The United States Renal Database System and Dialysis Outcomes and Practice Patterns Study (DOPPS) data reports, the Centers for Disease Control and Prevention and the US Food and Drug Administration websites, and published congress abstracts in 2020 were surveyed for relevant information.

RESULTS

Subgroups of patients with anaemia of CKD present a clinical challenge throughout the disease spectrum, including those with end-stage kidney disease, advanced age or resistance to or ineligibility for current standards of care (ie, oral or intravenous iron supplementation, erythropoietin-stimulating agents and red blood cell transfusions). In addition, those with an increased risk of adverse events because of comorbid conditions, such as cardiovascular diseases or diabetes, comprise special populations of patients with an unmet need for interventions to improve clinical outcomes. These comorbidities must be managed in parallel and may have a synergistic effect on overall disease severity.

CONCLUSIONS

Several therapies provide promising opportunities to address gaps with a standard of care, including hypoxia-inducible factor prolyl hydroxylase inhibitors, which stimulate haematopoiesis through promoting modest increases in serum erythropoietin and improved iron homeostasis. The critical issues in the management of anaemia of CKD in these challenging phenotypes and the clinical utility of new therapeutic agents in development for the treatment of anaemia of CKD should be assessed and the information should be made available to healthcare providers.

Molidustat for Renal Anemia in Nondialysis Patients Previously Treated with Erythropoiesis-Stimulating Agents: A Randomized, Open-Label, Phase 3 Study

INTRODUCTION

Erythropoiesis-stimulating agents (ESAs) are the current standard of care for anemia due to chronic kidney disease (CKD) in patients not undergoing dialysis. Molidustat, an oral hypoxia-inducible factor prolyl hydroxylase inhibitor, is being investigated as an alternative treatment for renal anemia. Molidustat was evaluated in five phase 3 studies, the molidustat once daily improves renal anemia by inducing erythropoietin (MIYABI) program. The present study investigated the safety and efficacy of molidustat in Japanese patients with renal anemia not undergoing dialysis and previously treated with ESAs.

METHODS

This was a 52-week, active-controlled, randomized (1:1), open-label, parallel-group, multicenter, phase 3 study in Japanese patients with anemia due to CKD (stages 3-5). Molidustat was initiated at 25 mg or 50 mg once daily according to previous ESA dose. The ESA darbepoetin alfa (darbepoetin) was initiated at a starting dose in accordance with the previous ESA dose and injected subcutaneously once every 2 or 4 weeks. Doses were regularly titrated to maintain hemoglobin (Hb) levels in the target range of 11.0-13.0 g/dL. The primary efficacy outcome was the mean Hb level and its change from baseline during the evaluation period (weeks 30-36). The safety outcomes included evaluation of all adverse events.

RESULTS

In total, 164 patients were randomized to receive molidustat (n = 82) or darbepoetin (n = 82). Baseline characteristics were well balanced. Mean (standard deviation) Hb levels at baseline were 11.31 (0.68) g/dL for molidustat and 11.27 (0.64) g/dL for darbepoetin. The mean (95% confidence interval [CI]) for mean Hb levels during the evaluation period for molidustat (11.67 [11.48-11.85] g/dL) and darbepoetin (11.53 [11.31-11.74] g/dL) was within the target range. Based on a noninferiority margin of 1.0 g/dL, molidustat was noninferior to darbepoetin regarding the change in mean Hb level during the evaluation period from baseline, with a least squares mean (95% CI) difference (molidustat-darbepoetin) of 0.13 (-0.15, 0.40) g/dL. The proportion of patients who reported at least 1 treatment-emergent adverse event (TEAE) was 92.7% for molidustat and 96.3% for darbepoetin. TEAEs leading to death were reported in 2 patients (2.4%) in the molidustat group and none in the darbepoetin group; serious TEAEs were reported in 32.9% and 26.8% of patients, respectively.

DISCUSSION/CONCLUSION

Molidustat was noninferior to darbepoetin and maintained Hb levels in the prespecified target range in patients with renal anemia not undergoing dialysis and previously treated with ESA. Molidustat was well tolerated, and no new safety signal was observed.

Phase 3 Randomized Study Comparing Vadadustat with Darbepoetin Alfa for Anemia in Japanese Patients with Nondialysis-Dependent CKD

BACKGROUND

Standard care for treating anemia in patients with CKD includes use of erythropoiesis-stimulating agents, which sometimes involves increased risks of cardiovascular morbidity and mortality. Previous studies in patients with anemia and nondialysis-dependent CKD (NDD-CKD) found significantly elevated hemoglobin levels with use of vadadustat, an oral hypoxia-inducible factor prolyl hydroxylase inhibitor, compared with placebo.

METHODS

In this phase 3, open-label, active-controlled noninferiority trial, we randomized 304 Japanese adults with anemia in NDD-CKD (including erythropoiesis-stimulating agent users and nonusers) to oral vadadustat or subcutaneous darbepoetin alfa for 52 weeks. The primary efficacy end point was average hemoglobin at weeks 20 and 24. Safety data included adverse events (AEs) and serious AEs.

RESULTS

A total of 151 participants received vadadustat and 153 received darbepoetin alfa. Least squares mean of the average hemoglobin at weeks 20 and 24 was 11.66 (95% confidence interval [95% CI], 11.49 to 11.84) g/dl for vadadustat and 11.93 (95% CI, 11.76 to 12.10) g/dl for darbepoetin alfa. The 95% CIs for both treatments were within the target hemoglobin range (11.0-13.0 g/dl), and the lower 95% confidence limit for the difference between groups (-0.50 g/dl) was above the predefined noninferiority margin (-0.75 g/dl), demonstrating noninferiority of vadadustat to darbepoetin alfa. Similar proportions of patients in each group reported AEs and serious AEs. The most frequent AEs with vadadustat were nasopharyngitis, diarrhea, and constipation.

CONCLUSIONS

In Japanese patients with NDD-CKD, vadadustat was noninferior to darbepoetin alfa, was effective up to week 52 in terms of average hemoglobin, and was generally well tolerated. These results suggest that vadadustat may be a potential treatment for anemia in this patient population.

Types of erythropoiesis-stimulating agents and risk of end-stage kidney disease and death in patients with non-dialysis chronic kidney disease

BACKGROUND

Despite the widespread use of erythropoiesis-stimulating agents (ESAs) to treat anaemia, the risk of adverse outcomes associated with the use of different types of ESAs in non-dialysis chronic kidney disease (CKD) is poorly investigated.

METHODS

From a pooled cohort of four observational studies, we selected CKD patients receiving short-acting (epoetin α/β; n = 299) or long-acting ESAs (darbepoetin and methoxy polyethylene glycol-epoetin β; n = 403). The primary composite endpoint was end-stage kidney disease (ESKD; dialysis or transplantation) or all-cause death. Multivariable Cox models were used to estimate the relative risk of the primary endpoint between short- and long-acting ESA users.

RESULTS

During follow-up [median 3.6 years (interquartile range 2.1-6.3)], the primary endpoint was registered in 401 patients [166 (72%) in the short-acting ESA group and 235 (58%) in the long-acting ESA group]. In the highest tertile of short-acting ESA dose, the adjusted risk of primary endpoint was 2-fold higher {hazard ratio [HR] 2.07 [95% confidence interval (CI) 1.37-3.12]} than in the lowest tertile, whereas it did not change across tertiles of dose for long-acting ESA patients. Furthermore, the comparison of ESA type in each tertile of ESA dose disclosed a significant difference only in the highest tertile, where the risk of the primary endpoint was significantly higher in patients receiving short-acting ESAs [HR 1.56 (95% CI 1.09-2.24); P = 0.016]. Results were confirmed when ESA dose was analysed as continuous variable with a significant difference in the primary endpoint between short- and long-acting ESAs for doses >105 IU/kg/week.

CONCLUSIONS

Among non-dialysis CKD patients, the use of a short-acting ESA may be associated with an increased risk of ESKD or death versus long-acting ESAs when higher ESA doses are prescribed.

Cardiovascular safety and efficacy of vadadustat for the treatment of anemia in non-dialysis-dependent CKD: Design and baseline characteristics

Current clinical practice guidelines for anemia management in non-dialysis-dependent chronic kidney disease (NDD-CKD) recommend the use of erythropoiesis-stimulating agents (ESAs) as standard of care. Vadadustat, an investigational oral hypoxia-inducible factor prolyl-hydroxylase inhibitor, stimulates endogenous erythropoietin production. The PRO₂TECT program comprises 2 global, Phase 3, randomized, open-label, active-controlled, sponsor-blind clinical trials to evaluate safety and efficacy of vadadustat vs darbepoetin alfa in adult patients with anemia associated with NDD-CKD. Patients recruited into the ESA-untreated NDD-CKD trial (N = 1751) had hemoglobin <10 g/dL and had not received an ESA within 8 weeks prior to inclusion in the study. Patients recruited into the ESA-treated NDD-CKD trial (N = 1725) had hemoglobin between 8 and 11 g/dL (US) or 9 and 12 g/dL (non-US) and were actively treated with an ESA for anemia associated with CKD. Trial periods in both trials include (1) correction/conversion (weeks 0-23); (2) maintenance (weeks 24-52); (3) long-term treatment (week 53 to end of treatment); and (4) safety follow-up (end-of-treatment to 4 weeks later). The primary safety endpoint is time to first adjudicated major adverse cardiovascular event, defined as all-cause mortality, nonfatal myocardial infarction, or nonfatal stroke, pooled across both trials. The primary efficacy endpoint in each trial is change in hemoglobin from baseline to primary evaluation period (weeks 24-36), comparing vadadustat vs darbepoetin alfa treatment groups. Demographics and baseline characteristics are similar among patients in both trials and broadly representative of the NDD-CKD population. These trials will help to evaluate the safety and efficacy of vadadustat for management of anemia associated with NDD-CKD.

Anemia in Chronic Kidney Disease: From Pathophysiology and Current Treatments, to Future Agents

Anemia is a common complication in chronic kidney disease (CKD), and is associated with a reduced quality of life, and an increased morbidity and mortality. The mechanisms involved in anemia associated to CKD are diverse and complex. They include a decrease in endogenous erythropoietin (EPO) production, absolute and/or functional iron deficiency, and inflammation with increased hepcidin levels, among others. Patients are most commonly managed with oral or intravenous iron supplements and with erythropoiesis stimulating agents (ESA). However, these treatments have associated risks, and sometimes are insufficiently effective. Nonetheless, in the last years, there have been some remarkable advances in the treatment of CKD-related anemia, which have raised great expectations. On the one hand, a novel family of drugs has been developed: the hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs). These agents induce, among other effects, an increase in the production of endogenous EPO, improve iron availability and reduce hepcidin levels. Some of them have already received marketing authorization. On the other hand, recent clinical trials have elucidated important aspects of iron supplementation, which may change the treatment targets in the future. This article reviews the current knowledge of the pathophysiology CKD-related anemia, current and future therapies, the trends in patient management and the unmet goals.

Burden of Anemia in Chronic Kidney Disease: Beyond Erythropoietin

Anemia is a frequent comorbidity of chronic kidney disease (CKD) and is associated with a considerable burden because of decreased patient health-related quality of life and increased healthcare resource utilization. Based on observational data, anemia is associated with an increased risk of CKD progression, cardiovascular events, and all-cause mortality. The current standard of care includes oral or intravenous iron supplementation, erythropoiesis-stimulating agents, and red blood cell transfusion. However, each of these therapies has its own set of population-specific patient concerns, including increased risk of cardiovascular disease, thrombosis, and mortality. Patients receiving dialysis or those who have concurrent diabetes or high blood pressure may be at greater risk of developing these complications. In particular, treatment with high doses of erythropoiesis-stimulating agents has been associated with increased rates of hospitalization, cardiovascular events, and mortality. Resistance to erythropoiesis-stimulating agents remains a therapeutic challenge in a subset of patients. Hypoxia-inducible factor transcription factors, which regulate several genes involved in erythropoiesis and iron metabolism, can be stabilized by a new class of drugs that act as inhibitors of hypoxia-inducible factor prolyl-hydroxylase enzymes to promote erythropoiesis and elevate hemoglobin levels. Here, we review the burden of anemia of chronic kidney disease, the shortcomings of current standard of care, and the potential practical advantages of hypoxia-inducible factor prolyl-hydroxylase inhibitors in the treatment of patients with anemia of CKD.

Vadadustat for anemia in chronic kidney disease patients on peritoneal dialysis: A phase 3 open-label study in Japan

Vadadustat is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor for the treatment of anemia in patients with chronic kidney disease (CKD). This phase 3, open-label, 24-week single-arm study evaluated the efficacy and safety of vadadustat in 42 Japanese CKD patients with anemia undergoing peritoneal dialysis. Patients received oral vadadustat for 24 weeks, initiated at 300 mg/day and doses were adjusted to achieve the target hemoglobin (Hb) range of 11.0-13.0 g/dL. Least squares mean of average Hb at weeks 20 and 24 was 11.35 g/dL, which was within the target range. The most frequent adverse events were catheter site infections (23.8%), which were not related to vadadustat treatment. Vadadustat was generally well tolerated and effective in controlling Hb levels within the target range, indicating the usefulness of vadadustat for treating anemia in Japanese CKD patients undergoing peritoneal dialysis.

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.

Anemia and Kidney Function Decline among the Middle-Aged and Elderly in China: A Population-Based National Longitudinal Study

Chronic kidney disease (CKD) is a public health burden, and anemia is common among patients with CKD. However, less is known regarding the longitudinal association between anemia and deterioration of kidney function among the general population. The China Health and Retirement Longitudinal Study is a nationally representative survey for households with members aged ≥ 45 years. Participants without creatinine and demographic data in 2011 and 2015 were excluded. Anemia was defined according to definitions of the World Health Organization. Rapid decline in kidney function was defined as a ≥16.9% (quartile 3) decline in estimated glomerular filtration rate (eGFR), calculated using the CKD-EPI equation during 2011-2015. Multivariate logistic regression and restricted cubic splines were used to explore their relationship. Altogether, 7210 eligible participants were included in the analysis, with a mean age of 58.6 ± 8.8 years. Rapid decline in kidney function occurred among 1802 (25.0%) participants. Those with kidney function decline were more likely to be older, male, and have anemia, lower eGFRs, hypertension, and cardiovascular disease (P < 0.05). Anemia, or hemoglobin, was independently associated with rapid decline in kidney function after adjusting for potential confounding factors (OR = 1.64, 95% CI, 1.32-2.04; OR = 0.90, 95% CI, 0.87-0.94, respectively). Restricted cubic splines showed a nonlinear relationship between hemoglobin and rapid decline in kidney function, especially for men with anemia (P < 0.05). In conclusion, anemia is an independent risk factor for progression of kidney function among the middle-aged and elderly population. Attentive management and intervention strategies targeting anemia could be effective to reduce the risk of kidney failure and improve the prognosis of the general population.

Hepcidin, iron indices and bone mineral metabolism in non-dialysis chronic kidney disease

BACKGROUND

Few studies have examined the association between hepcidin, iron indices and bone mineral metabolism in non-dialysis chronic kidney disease (CKD) patients.

METHODS

We reviewed the data of 2238 patients from a large-scale multicenter prospective Korean study (2011-16) and excluded 214 patients with missing data on markers and related medications of iron and bone mineral metabolism, hemoglobin, blood pressure and causes of CKD. Multivariate linear regression analysis was used to identify the association between iron and bone mineral metabolism.

RESULTS

The proportion of CKD Stages 1-5 were 16.2, 18.7, 37.1, 21.6 and 6.4%, respectively. Per each 10% increase in transferrin saturation (TSAT), there was a 0.013 mmol/L decrease in phosphorus [95% confidence interval (CI) -0.021 to -0.004; P = 0.003] and a 0.022 nmol/L increase in logarithmic 25-hydroxyvitamin D (Ln-25OHD) levels (95% CI 0.005-0.040; P = 0.019). A 1 pmol/L increase in Ln-ferritin was associated with a 0.080 ng/L decrease in Ln-intact parathyroid hormone (Ln-iPTH; 95% CI -0.122 to -0.039; P < 0.001). Meanwhile, beta (95% CI) per 1 unit increase in phosphorus, Ln-25OHD and Ln-iPTH for the square root of the serum hepcidin were 0.594 (0.257-0.932; P = 0.001), -0.270 (-0.431 to -0.108; P = 0.001) and 0.115 (0.004-0.226; P = 0.042), respectively. In subgroup analysis, the relationship between phosphorus, 25OHD and hepcidin was strongest in the positive-inflammation group.

CONCLUSIONS

Markers of bone mineral metabolism and iron status, including hepcidin, were closely correlated to each other. Potential mechanisms of the relationship warrant further studies.

Effect of ferric citrate on serum phosphate and fibroblast growth factor 23 among patients with nondialysis-dependent chronic kidney disease: path analyses

Background

Among patients with nondialysis-dependent chronic kidney disease (NDD-CKD) and iron-deficiency anemia (IDA), ferric citrate increases hemoglobin and iron parameters and reduces serum phosphate and fibroblast growth factor 23 (FGF23), a key phosphate-regulating hormone. We conducted post hoc analyses of a phase 3 trial to explore associations between iron replacement, serum phosphate changes and FGF23 regulation.

Methods

We employed multivariable regression and longitudinal mixed-effects models to identify and confirm, respectively, whether baseline demographic and laboratory variables were associated with ferric citrate-induced changes in serum phosphate or FGF23 concentrations. We employed path analyses to determine whether changes in FGF23 concentrations were mediated via changes in serum phosphate and/or transferrin saturation (TSAT).

Results

We analyzed a total of 117 and 115 ferric citrate-treated and placebo-treated patients, respectively. At 16 weeks, ferric citrate significantly reduced serum phosphate versus placebo (P = 0.006) only among patients with elevated baseline serum phosphate (≥4.5 mg/dL) and did not reduce serum phosphate among patients with baseline serum phosphate within the population reference range. Ferric citrate reduced intact FGF23 and C-terminal FGF23 partially via changes in TSAT (for C-terminal FGF23) and serum phosphate (for intact FGF23) and partially via unknown/unmeasured mechanisms.

Conclusions

Ferric citrate reduced serum FGF23 concentrations (partially via effects on serum phosphate and iron balance) and did not reduce serum phosphate among patients with baseline serum phosphate concentrations within the population reference range.

Etiological spectrum of anemia in non-dialysis-dependent chronic kidney disease: A single-center study from India

A retrospective study was conducted over seven years and it aimed to find out various causes of anemia among patients with chronic kidney disease (CKD). The study included nondialysis-dependent adult CKD patients who underwent anemia evaluation. A total of 584 patients were studied. Three hundred and twenty-one (55%) patients were male and 263 (45%) were female. The mean age of the patients was 55.5 ± 14 years. One hundred and seventy-eight (30.5%) had a diabetic CKD and 406 (69.5%) had a nondiabetic CKD. Seventy-two (12.3%) patients were in CKD Stage 3, 193 (33%) patients in CKD Stage 4, and 319 (54.6%) patients in CKD Stage 5. The mean hemoglobin was 9.2 ± 2.2 g/dL. There was a progressive fall in hemoglobin with increasing severity of CKD and in CKD Stage 3, 4, and 5 the mean hemoglobin was 10 ± 2.2, 9.4 ± 2.1, and 8.4 ± 1.9 g/dL, respectively (P = 0.001). Most (47.4%) patients had moderate anemia followed by anemia of mild (31.4%) and severe (21.4%) degrees. Three hundred and seven (52.6%) patients had percent transferrin saturation (TSAT) <20% (functional iron deficiency). One hundred and sixty-two (27.7%) patients had serum ferritin <100 ng/mL (absolute iron deficiency); 334 (57.2%) patients had serum ferritin 100-500 ng/mL, but in 175 (52.4%) of them, TSAT was <20%; 88 (15.1%) patients had serum ferritin >500 ng/mL (58 (65.6%) were C-reactive protein (CRP) + and 55 (62.5%) had TSAT <20%). Overall, 392 (67.1%) patients had functional or absolute iron deficiency. One-third of the patients had elevated CRP levels. The anemia was macrocytic in 20.4% suggesting deficiency of folic acid and/or Vitamin B₁₂. A high proportion (74.6%) of patients with normocytic anemia had iron deficiency. In the majority of nondialysis-dependent CKD patients, the etiology of anemia may be multifactorial; therefore, the treatment should be determined by documented causes of anemia.

Association between anemia and renal prognosis in autosomal dominant polycystic kidney disease: a retrospective study

BACKGROUND

Though anemia is a sign of poor renal prognosis in chronic kidney disease (CKD), hemoglobin (Hb) levels are typically higher in autosomal dominant polycystic kidney disease (ADPKD) than in other kidney diseases, and anemia has not been examined as a potential prognosticator. Thus, we investigated anemia as a factor for renal prognosis in ADPKD.

METHODS

In total, 115 non-dialysis patients, 48 men and 67 women, with ADPKD were evaluated. The renal outcome of a 50% reduction in the estimated glomerular filtration rate or renal replacement therapy was examined using the Cox regression analysis and Kaplan-Meier analysis.

RESULTS

Patients were followed for a median of 5.5 years and 50 patients had reached the end point. The mean age of the patients at the first visit was 45.9 ± 13.3 years. The overall mean Hb was 12.90 ± 1.85 g/dL, and the mean Hb in men and women was 13.82 ± 1.72 g/dL and 12.25 ± 1.65 g/dL, respectively. Hb levels and uric protein content were statistically significant factors for poor renal prognosis, while hypertension and genetic mutations failed to reach significance. Furthermore, statistical significance was found in men with Hb < 12 g/dL and in women with Hb < 11 g/dL. Anemia had significant association with kidney disease progression in patients with ADPKD.

CONCLUSIONS

We found that anemia might be a factor for poor renal prognosis in ADPKD. Furthermore, a sex difference was found, wherein men with Hb < 12 g/dL and women with Hb < 11 g/dL were at risk of renal disease progression.

Effects of oral iron and calcium supplement on the pharmacokinetics and pharmacodynamics of molidustat: an oral HIF-PH inhibitor for the treatment of renal anaemia

PURPOSE

The present studies assessed the drug-drug interaction of molidustat, a hypoxia-inducible factor prolyl hydroxylase inhibitor, with iron and calcium supplements, which are common medications in patients with anaemia due to chronic kidney disease (CKD).

METHODS

Forty-two healthy men received molidustat alone (fasted or fed) or combined with oral iron(II) or calcium(II), given immediately before or between 4 h before and 1 h after molidustat in three randomized, open-label, crossover studies (12-15 participants per study). Molidustat AUC and C_max were assessed as the main pharmacokinetic parameters, and endogenous erythropoietin (EPO) was measured to evaluate pharmacodynamics.

RESULTS

Depending on prandial state, concomitant intake of iron(II) reduced molidustat AUC and C_max by 50-75% and 46-84%, respectively, and EPO AUC_(0-24) and C_max by 31-44% and 36-48%, respectively. The influence of iron(II) declined with increasing the time interval to the intake of molidustat, with reductions in molidustat AUC and C_max of 9% and 10%, respectively, when iron(II) intake occurred 4 h before molidustat. Accordingly, effects on endogenous EPO were less pronounced with increased time separation between oral iron(II) and molidustat intake. Calcium(II) reduced molidustat AUC and C_max by 15% and 47%, respectively, without influence on EPO response. All treatments were well tolerated.

CONCLUSIONS

In contrast to concomitant oral intake of calcium, the effect of oral iron supplements on molidustat pharmacokinetics and pharmacodynamics should be considered, and the two agents should be administered with an appropriate time separation.

Relationship between Cardiac Geometry and Serum Hepcidin in Chronic Kidney Disease: Analysis from the KNOW-CKD Study

BACKGROUND

Few studies have examined the relationship between cardiac function and geometry and serum hepcidin levels in patients with chronic kidney disease (CKD). We aimed to identify the relationship between cardiac function and geometry and serum hepcidin levels.

METHODS

We reviewed data of 1,897 patients in a large-scale multicenter prospective Korean study. Logistic regression analysis was used to identify the relationship between cardiac function and geometry and serum hepcidin levels.

RESULTS

The mean relative wall thickness (RWT) and left ventricular mass index (LVMI) were 0.38 and 42.0 g/m^2.7, respectively. The mean ejection fraction (EF) and early diastolic mitral inflow to annulus velocity ratio (E/e') were 64.1% and 9.9, respectively. Although EF and E/e' were not associated with high serum hepcidin, RWT and LVMI were significantly associated with high serum hepcidin levels in univariate logistic regression analysis. In multivariate logistic regression analysis after adjusting for variables related to anemia, bone mineral metabolism, comorbidities, and inflammation, however, only each 0.1-unit increase in RWT was associated with increased odds of high serum hepcidin (odds ratio, 1.989; 95% confidence interval, 1.358-2.916; P < 0.001). In the subgroup analysis, the independent relationship between RWT and high serum hepcidin level was valid only in women and patients with low transferrin saturation (TSAT).

CONCLUSION

Although the relationship was not cause-and-effect, increased RWT was independently associated with high serum hepcidin, particularly in women and patients with low TSAT. The relationship between cardiac geometry and serum hepcidin in CKD patients needs to be confirmed in future studies.

Decreased B1 and B2 Lymphocytes Are Associated With Mortality in Elderly Patients With Chronic Kidney Diseases

Aim: Loss of renal function is associated with immune deficiency; however, few studies have addressed the role of B lymphocytes in elderly patients with chronic kidney disease (CKD). In this study, we examined the distribution and the relationship of the B lymphocyte subpopulation with clinical outcomes in elderly CKD patients. Methods: In this study, a total of 380 patients (312 CKD patients and 68 non-CKD controls) were recruited. Venous blood samples were analyzed by flow cytometry to determine the following B cell subsets: total B cells (CD19+), innate B1 cells (CD19+CD5+), and conventional B2 cells (CD19+CD5-). Correlations between the B cell subsets with clinical features and patient prognosis were analyzed. Results: A total of 380 patients (mean age 82.29 ± 6.22 years, 76.3% male) were included. The median follow-up time was 37.0 months (range, 1-109 months); 109 (28.7%) patients died. The main causes of death were infections (59.6%) and cardiovascular diseases (22.9%). Correlation analysis showed that levels of serum creatinine (SCr), blood urea nitrogen (BUN), and CKD were negatively associated with B1 cells. However, lymphocytes, T lymphocytes, and estimated glomerular filtration rate (eGFR) were positively correlated with B1 cells (all P < 0.05). B2 cells were negatively associated with age, SCr, cystatin C, BUN, and CKD, and were positively correlated with hemoglobin, lymphocytes, T lymphocytes, NK cells, and eGFR (all P < 0.05). Patient survival was significantly better in patients with B cells > 0.05 × 10⁹/L, B1 cells > 0.02 × 10⁹/L, and B2 cells > 0.04 × 10⁹/L. Multivariate Cox regression analysis showed that B1 cells > 0.02 × 10⁹/L [hazard ratio (HR) = 0.502, 95% confidence interval (CI): 0.297-0.851, P = 0.010] and B2 cells > 0.04 × 10⁹/L (HR = 0.536, 95% CI: 0.319-0.901, P = 0.019) were independent protective factors for all-cause mortality. Conclusions: Our results showed that B1 and B2 cells exhibited a significantly negative correlation with the progression of CKD in elderly patients. Moreover, B1 and B2 cells were independent prognostic factors for survival, which indicates that the decrease in B cells may be associated with the progression of kidney diseases.

Ex vivo quantification of lanthanum and gadolinium in post-mortem human tibiae with estimated barium and iodine concentrations using K x-ray fluorescence

OBJECTIVES

Lanthanum (La) and gadolinium (Gd) are known to deposit in bone of exposed populations, namely those who are orally administered lanthanum carbonate (LaC, La₂(CO₃)₃) or are injected with Gd-based contrast agents, respectively. In this work, bone La and Gd concentrations from the environment and diet were measured using x-ray fluorescence in ten post-mortem human tibiae. As a secondary objective, bone barium (Ba) and iodine concentrations were estimated.

APPROACH

Two calibration lines were produced for La and Gd and the minimum detection limits (MDLs) of the system were determined using a 180° irradiation-detection geometry.

MAIN RESULTS

The MDLs of the system were 0.4 µg La g^-1 bone mineral and 0.5 µg Gd g^-1 bone mineral. The mean concentrations were  -0.02  ±  0.1 µg La g^-1 bone mineral and 0.1  ±  0.2 µg Gd g^-1 bone mineral in tibiae. The average Ba and iodine concentrations estimated from the experimental La calibration line and Monte-Carlo derived sensitivity factors were determined to be 3.4  ±  0.8 µg Ba g^-1 bone mineral and  -0.5  ±  0.3 µg iodine g^-1 bone mineral. Since it was discovered that four donors previously received an iodine-based contrast agent, the mean concentrations in these donors was 27.8  ± 28.4 µg iodine g^-1 bone mineral.

SIGNIFICANCE

The XRF system has determined baseline concentrations of these four heavy metals in trace quantities from natural exposure pathways (with the exception of iodine in four donors). This indicates that the system can measure low levels in ex vivo tibiae samples and can potentially be further developed for in vivo studies involving live subjects who are directly exposed to these metals.

Iron Regulation by Molidustat, a Daily Oral Hypoxia-Inducible Factor Prolyl Hydroxylase Inhibitor, in Patients with Chronic Kidney Disease

BACKGROUND/AIMS

The current treatment for anemia associated with chronic kidney disease (CKD) includes the administration of erythropoiesis stimulating agents (ESAs) combined with iron supplementation. Molidustat, a hypoxia-inducible factor prolyl hydroxylase inhibitor, has potential to treat anemia associated with CKD through increased erythropoietin production and improved iron availability. Here, we report the effect of molidustat on iron metabolism.

METHOD

Parameters of iron metabolism were monitored in three 16-week, randomized, controlled, phase 2 studies assessing the safety and efficacy of molidustat in the treatment of anemia associated with CKD in different populations: treatment-naïve and previously ESA-treated patients not on dialysis, and previously ESA-treated patients on hemodialysis. Iron supplementation was left at the discretion of the investigator.

RESULTS

In treatment-naïve patients not on dialysis, transferrin saturation (TSAT), hepcidin, ferritin, and iron concentrations decreased with molidustat, whereas total iron binding capacity (TIBC) increased. Similar results were observed in previously ESA-treated patients not on dialysis, although changes in those parameters were larger in treatment-naïve than in previously ESA-treated patients. In previously ESA-treated patients receiving hemodialysis, hepcidin concentration and TIBC remained stable with molidustat, whereas TSAT and ferritin and iron concentrations increased. Generally, similar trends were observed in secondary analyses of subgroups of patients not receiving iron supplementation.

CONCLUSIONS

Molidustat is a potential alternative to standard treatment of anemia associated with CKD, with a different mechanism of action. In patients not receiving dialysis, molidustat increases iron availability. In patients receiving hemodialysis, further investigation is required to understand fully the mechanisms underlying iron mobilization associated with molidustat.

Urinary uromodulin independently predicts end-stage renal disease and rapid kidney function decline in a cohort of chronic kidney disease patients

Data on risk factors predicting rapid progression to end-stage renal disease (ESRD) or short-term kidney function decline (i.e., within 1 year) in chronic kidney disease (CKD) are rare but urgently needed to plan treatment. This study describes the association and predictive value of urinary uromodulin (uUMOD) for rapid progression of CKD.We assessed uUMOD, demographic/treatment parameters, estimated glomerular filtration rate (eGFR), and proteinuria in 230 CKD patients stage I-V. ESRD and 25% decline of eGFR was documented at the end of follow-up period and used as a composite endpoint. Association between logarithmic uUMOD and eGFR/proteinuria was calculated using linear regression analysis, adjusting for age, gender, and body mass index. We performed multivariable Cox proportional hazard regression analysis to evaluate the association of uUMOD with the composite endpoint. Therefore, patients were categorized into quartiles. The predictive value of uUMOD for the above outcomes was assessed using receiver-operating characteristic (ROC) curve analysis.Follow-up was 57.3 ± 18.7 weeks, baseline age was 60 (18;92) years, and eGFR was 38 (6;156) mL/min/1.73 m. Forty-seven (20.4%) patients reached the composite endpoint. uUMOD concentrations were directly associated with eGFR and inversely associated with proteinuria (β = 0.554 and β = -0.429, P < .001). In multivariable Cox regression analysis, the first 2 quartiles of uUMOD concentrations had a hazard ratio (HR) of 3.589 [95% confidence interval (95% CI) 1.002-12.992] and 5.409 (95% CI 1.444-20.269), respectively, in comparison to patients of the highest quartile (≥11.45 μg/mL) for the composite endpoint. In ROC-analysis, uUMOD predicted the composite endpoint with good sensitivity (74.6%) and specificity (76.6%) at an optimal cut-off at 3.5 μg/mL and area under the curve of 0.786 (95% CI 0.712-0.860, P < .001).uUMOD was independently associated with ESRD/rapid loss of eGFR. It might serve as a robust predictor of rapid kidney function decline and help to better schedule arrangements for future treatment.

Long-Term Efficacy and Safety of Molidustat for Anemia in Chronic Kidney Disease: DIALOGUE Extension Studies

BACKGROUND

Molidustat, a novel hypoxia-inducible factor-prolyl hydroxylase inhibitor, is being investigated for the treatment of anemia associated with chronic kidney disease (CKD). The efficacy and safety of molidustat were recently evaluated in three 16-week phase 2b studies. Here, we report the results of two long-term extension studies of molidustat.

METHODS

Both studies were parallel-group, open-label, multicenter studies of ≤36 months' duration, in patients with anemia due to CKD, and included an erythropoiesis-stimulating agent as active control. One study enrolled patients not receiving dialysis (n = 164), and the other enrolled patients receiving hemodialysis (n = 88). The primary efficacy variable for both studies was change in blood hemoglobin (Hb) level from baseline to each post-baseline visit, and safety outcomes included adverse events (AEs).

RESULTS

In patients not on dialysis, the mean ± SD Hb concentrations at baseline were 11.28 ± 0.55 g/dL for molidustat and 11.08 ± 0.51 g/dL for darbepoetin. The mean ± SD blood Hb concentrations throughout the study (defined as mean of each patient's overall study Hb levels) were 11.10 ± 0.508 and 10.98 ± 0.571 g/dL in patients treated with molidustat and darbepoetin, respectively. Similar proportions of patients reported at least one AE in the molidustat (85.6%) and darbepoetin (85.7%) groups. In patients on dialysis, mean ± SD Hb levels at baseline were 10.40 ± 0.70 and 10.52 ± 0.53 g/dL in the molidustat and epoetin groups, respectively. The mean ± SD blood Hb concentrations during the study were 10.37 ± 0.56 g/dL in the molidustat group and 10.52 ± 0.47 g/dL in the epoetin group. Proportions of patients who reported at least one AE were 91.2% in the molidustat group and 93.3% in the epoetin group.

CONCLUSIONS

Molidustat was well tolerated for up to 36 months and appears to be an effective alternative to darbepoetin and epoetin in the long-term management of anemia associated with CKD.

Clinical and pathological factors of renal anaemia in patients with IgA nephropathy in Chinese adults: a cross-sectional study

OBJECTIVE

Few studies with large sample populations concerning renal anaemia and IgA nephropathy have been reported worldwide. The purpose of this cross-sectional study was to examine the clinical and pathological characteristics and influencing factors associated with renal anaemia in patients with IgA nephropathy, which is the most common aetiology of chronic kidney disease.

METHODS

A total of 462 hospitalised patients with IgA nephropathy confirmed by renal biopsy who met the inclusion criteria were consecutively recruited from January 2014 to January 2016. Their general information, routine blood test results, blood chemistries, estimated glomerular filtration rates (eGFRs) and renal pathologies were collected. The Oxford classification was used to characterise the renal pathologies. Univariable and multivariate logistic regression models were used to analyse the influencing factors of anaemia associated with IgA nephropathy.

RESULTS

The incidence of renal anaemia was 28.5% (132/462 patients) in our study (21.3% in males and 38.9% in females). The anaemia type was primarily normocytic and normochromic. The rate of anaemia in patients with eGFR values of 30-59 mL/min/1.73 m² was higher than that in patients with an eGFR >60 mL/min/1.73 m² (42.9% vs 17.8%, p<0.001). Notably, in the group with eGFR values <15 mL/min/1.73 m², the anaemia rate was 100%. Logistic regression analysis showed that factors affecting anaemia in patients with IgA nephropathy included being female (OR 3.02, 95% CI 1.76 to 5.17), low albumin levels (OR 0.87, 95% CI 0.82 to 0.93), reduced eGFR values (OR 0.98, 95% CI 0.97 to 0.99) and renal tubulointerstitial lesions >50% (OR 2.57, 95% CI 1.22 to 5.40).

CONCLUSIONS

The female sex, hypoalbuminaemia, reduced eGFR levels and severe renal tubulointerstitial lesions were correlated with renal anaemia in patients with IgA nephropathy. These results provide new insight into our understanding of anaemia in IgA nephropathy and may improve the management and treatment of clinical renal anaemia.

Effect of achieved hemoglobin level on renal outcome in non-dialysis chronic kidney disease (CKD) patients receiving epoetin beta pegol: MIRcerA CLinical Evidence on Renal Survival in CKD patients with renal anemia (MIRACLE-CKD Study)

Background

Previous randomized-controlled trials have shown that targeting higher hemoglobin (Hb) levels using high dose of ESA in non-dialysis chronic kidney disease (NDCKD) patients resulted in poorer cardiovascular outcome; however, it remains unknown how high Hb levels achieved by ESA in clinical practice dose could affect renal outcome.

Methods

In a multicenter prospective observational study, Japanese NDCKD patients with an estimated glomerular filtration rate (eGFR) of ≥ 6 mL/min/1.73 m² and renal anemia (Hb < 11 g/dL) treated with epoetin beta pegol (C.E.R.A.) for the first time were divided into two groups by Hb level (< 11 g/dL or ≥ 11 g/dL) in Week 12 of C.E.R.A. treatment (Week 12 Hb). Renal outcome was defined as time until the first occurrence of one of the following: progression to renal replacement therapy, serum creatinine doubling, or eGFR falling below 6 mL/min/1.73 m². The effect of Week 12 Hb on the onset of renal events was assessed by the Kaplan–Meier and multivariate Cox regression analyses.

Results

In the landmark analysis which included 2851 patients, Kaplan–Meier renal survival rate was 37.57% in the < 11 g/dL group and was significantly higher (51.47%) in the ≥ 11 g/dL group (P < 0.0001). Multivariate Cox regression analysis revealed significantly higher risk of renal events in the < 11 g/dL group than in the ≥ 11 g/dL group (hazard ratio: 1.26; 95% confidence interval: 1.05–1.51; P = 0.0103).

Conclusions

The results suggest that week 12 Hb levels ≥ 11 g/dL achieved with C.E.R.A. treatment were associated with better renal outcomes than Hb levels < 11 g/dL.

Electronic supplementary material

The online version of this article (10.1007/s10157-018-1649-0) contains supplementary material, which is available to authorized users.

Association between responsiveness to methoxy polyethylene glycol-epoetin beta and renal survival in patients with non-dialysis-dependent chronic kidney disease: A pooled analysis of individual patient-level data from clinical trials

AIM

The association between responsiveness to continuous erythropoietin-receptor activator (CERA) and renal survival in patients with non-dialysis-dependent chronic kidney disease (NDD-CKD) is uncertain.

METHODS

We performed a pooled analysis of individual patient-level data drawn from five clinical trials involving CERA administration. Based on the responsiveness to CERA, patients were classified into poor- or good-response groups. Primary endpoints were defined as the initiation of dialysis or a 30% decrease in the estimated glomerular filtration rate (eGFR) from baseline. We set the landmark time point at 12 weeks after the start of CERA, from which we evaluated the time to the first renal event. The cumulative renal survival rates were calculated for each group using the Kaplan-Meier method. The adjusted hazard ratio was calculated using a stratified Cox regression model.

RESULTS

Of 408 patients, 226 were analyzed. Haemoglobin levels and eGFRs were significantly lower in the poor-response group (n = 113) than in the good-response group (n = 113). Renal events occurred in 36.3% of the poor-response group and in 23.0% of the good-response group. The intergroup difference in renal survival rates was significant (log-rank test, P = 0.03) and the adjusted hazard ratio was 1.71 (95% confidence interval, 1.03-2.83), indicating an unfavorable outcome in the poor-response group.

CONCLUSION

Hyporesponsiveness to CERA was associated with poor renal survival, consistent with the results of the conventional erythropoiesis-stimulating agent (ESA). It is recommended that a randomized controlled trial on CERA use be performed in patients with NDD-CKD with ESA-hyporesponsive anaemia.

Decline of kidney function during the pre-dialysis period in chronic kidney disease patients: a systematic review and meta-analysis

Purpose

Substantial heterogeneity exists in reported kidney function decline in pre-dialysis chronic kidney disease (CKD). By design, kidney function decline can be studied in CKD 3–5 cohorts or dialysis-based studies. In the latter, patients are selected based on the fact that they initiated dialysis, possibly leading to an overestimation of the true underlying kidney function decline in the pre-dialysis period. We performed a systematic review and meta-analysis to compare the kidney function decline during pre-dialysis in CKD stage 3–5 patients, in these two different study types.

Patients and methods

We searched PubMed, EMBASE, Web of Science and Cochrane to identify eligible studies reporting an estimated glomerular filtration rate (eGFR) decline (mL/min/1.73 m²) in adult pre-dialysis CKD patients. Random-effects meta-analysis was performed to obtain weighted mean annual eGFR decline.

Results

We included 60 studies (43 CKD 3–5 cohorts and 17 dialysis-based studies). The meta-analysis yielded a weighted annual mean (95% CI) eGFR decline during pre-dialysis of 2.4 (95% CI: 2.2, 2.6) mL/min/1.73 m² in CKD 3–5 cohorts compared to 8.5 (95% CI: 6.8, 10.1) in dialysis-based studies (difference 6.0 [95% CI: 4.8, 7.2]).

Conclusion

To conclude, dialysis-based studies report faster mean annual eGFR decline during pre-dialysis than CKD 3–5 cohorts. Thus, eGFR decline data from CKD 3–5 cohorts should be used to guide clinical decision making in CKD patients and for power calculations in randomized controlled trials with CKD progression during pre-dialysis as the outcome.

Night Sleep Duration and Risk of Incident Anemia in a Chinese Population: A Prospective Cohort Study

The purpose was to study the association between sleep duration and the prevalence of anemia in Chinese people. There were 84,791 participants (men: 79.1%; women: 20.9%) aged 18–98 years in the prospective study. We divided the participants into five categories based on the individual sleep duration: ≤5 h, 6 h, 7 h(reference), 8 h, and ≥9 h. Anemia was defined based on hemoglobin <12 g/dL for men and <11 g/dL for women. The Cox proportional hazards model was used to assess the association between sleep duration and anemia. During median follow-up of 7.9 years, 2698 cases of anemia had occurred. The HRand (95% CI) of anemia (7 h as the reference group) for individuals reporting ≤5 h, 6 h, 8 h, and ≥9 h were 1.23(1.04–1.45), 1.26(1.11–1.44), 1.04(0.92–1.16) and 1.42(1.08–1.86), respectively. It showed that there was a significant interaction on the risk of anemia between sleep duration and sex in the secondary analysis (p < 0.001).The significant association between long sleepduration and anemia was found in women (HR, 2.29; 95% CI, 1.56–3.37), not in men(HR, 0.90; 95% CI, 0.60–1.34). Both short and long night sleep duration were associated with increased risk of anemia.

Serum Hepcidin and Iron Indices Affect Anemia Status Differently According to the Kidney Function of Non-Dialysis Chronic Kidney Disease Patients: Korean Cohort Study For Outcome in Patients with Chronic Kidney Disease (KNOW-CKD)

BACKGROUND/AIMS

No studies have examined the association among serum hepcidin, iron indices, or anemia status based on the kidney function of non-dialysis chronic kidney disease (CKD) patients.

METHODS

We reviewed data of 2238 patients from a large-scale multicenter prospective Korean study (2011-2016) and excluded 198 patients with missing data regarding serum hepcidin, hemoglobin, transferrin saturation (TSAT), ferritin, and usage of erythropoiesis-stimulating agents (ESA) or supplemental iron and 363 patients using ESA or supplemental iron. Finally, 1677 patients were included.

RESULTS

The mean patient age was 53.5 years, and 65.4% were men. TSAT and serum hepcidin were significantly associated with anemia status, whereas serum ferritin was not, regardless of anemia severity. For patients with an estimated glomerular filtration rate (eGFR) ≥45 mL/min/1.73 m2, a 10% increase of TSAT was associated with hemoglobin <13 g/dL (odds ratio [OR], 0.628; 95% confidence interval [CI], 0.515-0.765; P<0.001) and hemoglobin <11.5 g/dL (OR, 0.672; 95% CI, 0.476-0.950; P=0.024), whereas a 10-ng/mL increase of serum hepcidin was associated with hemoglobin <11.5 g/dL (OR, 1.379; 95% CI, 1.173-1.620; P<0.001) and hemoglobin <10.0 g/dL (OR, 1.360; 95% CI, 1.115-1.659; P=0.002) for patients with eGFR <45 mL/min/1.73 m2 according to multivariate logistic analysis.

CONCLUSIONS

TSAT was associated with less severe anemia in early CKD patients. Serum hepcidin was associated with more severe anemia in advanced CKD patients.

Uric acid metabolism of kidney and intestine in a rat model of chronic kidney disease

Uric acid (UA) is a potential risk factor of the progression of chronic kidney disease (CKD). Recently, we reported that intestinal UA excretion might be enhanced via upregulation of the ATP-binding cassette transporter G2 (Abcg2) in a 5/6 nephrectomy (Nx) rat model. In the present study, we examined the mRNA and protein expressions of UA transporters, URAT1, GLUT9/URATv1, ABCG2 and NPT4 in the kidney and ileum in the same rat model. Additionally, we investigated the Abcg2 mRNA expression of ileum in hyperuricemic rat model by orally administering oxonic acid. Male Wistar rats were randomly assigned to three groups consisting of Nx group, oxonic acid-treated (Ox) group and sham-operated control group, and sacrificed at 8 weeks. Creatinine and UA were measured and the mRNA expressions of UA transporters in the kidney and intestine were evaluated by a real time PCR. UA transporters in the kidney sections were also examined by immunohistochemistry. Serum creatinine elevated in the Nx group whereas serum UA increased in the Ox group. Both the mRNA expression and the immunohistochemistry of the UA transporters were decreased in the Nx group, suggesting a marginal role in UA elevation in decreased kidney function. In contrast, the mRNA expression of Abcg2 in the ileum significantly increased in the Ox group. These results suggest that the upregulation of Abcg2 mRNA in the ileum triggered by an elevation of serum UA may play a compensatory role in increasing intestinal UA excretion.

Prevalence, awareness, and treatment of anemia in Chinese patients with nondialysis chronic kidney disease: First multicenter, cross-sectional study

This was the first multicenter, cross-sectional survey to assess the prevalence of anemia, patient awareness, and treatment status in China. Data of patients with chronic kidney disease (CKD; age, 18-75 years; both out- and inpatients) from 25 hospitals in Shanghai, seeking medical treatment at the nephrology department, were collected between July 1, 2012 and August 31, 2012. The prevalence, awareness, and treatment of anemia in patients with nondialysis CKD (ND-CKD) were assessed. Anemia was defined as serum hemoglobin (Hb) levels ≤12 g/dL in women and ≤13 g/dL in men. A total of 2420 patients with ND-CKD were included. Anemia was established in 1246 (51.5%) patients: 639 (51.3%) men and 607 (48.7%) women. The prevalence of anemia increased with advancing CKD stage (χtrend = 675.14, P < 0.001). Anemia was more prevalent in patients with diabetic nephropathy (68.0%) than in patients with hypertensive renal damage (56.6%) or chronic glomerulonephritis (46.1%, both P < 0.001). Only 39.8% of the anemic patients received treatment with erythropoietin and 27.1% patients received iron products; furthermore, 22.7% of the patients started receiving treatment when their Hb level reached 7 g/dL. The target-achieving rate (Hb at 11-12 g/dL) was only 8.2%. Of the 1246 anemia patients, only 7.5% received more effective and recommended intravenous supplementation. Anemia is highly prevalent in patients with ND-CKD in China, with a low target-achieving rate and poor treatment patterns. The study highlights the need to improve multiple aspects of CKD management to delay the progression of renal failure.