Anaemia management and mortality risk in chronic kidney disease

Functional erythropoietin-hepcidin axis in recombinant human erythropoietin independent haemodialysis patients

AIM

Relatively few haemodialysis (HD) patients remain independent of recombinant human erythropoietin ('rHU-EPO free patients'). We investigated the role of EPO and hepcidin, two key hormones involved in anaemia.

METHODS

We report a monocentric case-control series. Iron status, EPO and hepcidin levels were analysed in 15 Adult HD (Age > 18 years) with a stable haemoglobin (Hb) level that have not received rHU-EPO for at least 6 months (=rHU-EPO free patients); and in 60 controls with a stable rHU-EPO dose and Hb level.

RESULTS

The rHU-EPO free patients had a higher Hb level compared to controls (12.1 ± 0.99 g/dL vs 11.1 ± 0.73, P = 0.0014), and a lower ferritin level (183 ± 102 vs 312 ± 166 ng/mL, P = 0.001). Hepcidin levels were lower in the rHU-EPO free patients (12.53 ± 10.46 ng/mL) compared to the controls (37.95 ± 34.33 ng/mL), P = 0.0033. Hepcidin levels correlated significantly with ferritin levels; but neither with transferrin saturation, C-reactive protein nor EPO levels. Unsupervised analysis revealed that rHU-EPO free patients had a specific clinical/biological profile (presence of renal cyst, longer dialysis vintage, lower ferritin, and EPO and hepcidin levels compared to the control group). Finally, we showed that a lower ferritin level might be a surrogate marker of a lower hepcidin status in this population.

CONCLUSION

Recombinant human erythropoietin free patients seem to restore the EPO-hepcidin axis that is critical for erythropoiesis. A specific combination of clinical and biological parameters may help to detect future rHU-EPO free patients.

Mathematical model to predict B-type natriuretic peptide levels in haemodialysis patients

AIM

Clinical interpretation of B-type natriuretic peptide (BNP) levels in haemodialysis (HD) patients for fluid management remains elusive.

METHODS

We conducted a retrospective observational monocentric study. We built a mathematical model to predict BNP levels, using multiple linear regressions. Fifteen clinical/biological characteristics associated with BNP variation were selected. A first cohort of 150 prevalent HD (from September 2015 to March 2016) was used to build several models. The best model proposed was internally validated in an independent cohort of 75 incidents HD (from March 2016 to December 2017).

RESULTS

In cohort 1, mean BNP level was 630 ± 717 ng/mL. Cardiac disease (CD - stable coronary artery disease and/or atrial fibrillation) was present in 45% of patients. The final model includes age, systolic blood pressure, albumin, CD, normo-hydrated weight (NHW) and the fluid overload (FO) assessed by bio-impedancemetry. The correlation between the measured and the predicted log-BNP was 0.567 and 0.543 in cohorts 1 and 2, respectively. Age (β = 3.175e^-2 , P < 0.001), CD (β = 5.243e^-1 , P < 0.001) and FO (β = 1.227e^-1 , P < 0.001) contribute most significantly to the BNP level, respectively, but within a certain range. We observed a logistic relationship between BNP and age between 30 and 60 years, after which this relationship was lost. BNP level was inversely correlated with NHW independently of CD. Finally, our model allows us to predict the BNP level according to the FO.

CONCLUSION

We developed a mathematical model capable of predicting the BNP level in HD. Our results show the complex contribution of age, CD and FO on BNP level.

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.

Burden of Anemia in Chronic Kidney Disease Patients in Japan: A Literature Review

Anemia is a common complication for patients with chronic kidney disease (CKD) and is associated with cardiovascular comorbidities and reduced quality of life. The incidence of anemia increases as kidney function declines and affects approximately 32% of Japanese patients with stage 3-5 CKD. This review examined the current literature on anemia in CKD patients in Japan to provide an overview of the burden of anemia in CKD. Medline, Embase, and Igaku Chuo Zasshi databases were searched to identify relevant manuscripts and abstracts published from 2004 onward. The population included CKD patients with anemia, and the outcomes of interest were epidemiology, economic, humanistic, and treatment patterns. Observational studies, database analysis, and economic evaluation studies were included in the analysis. A total of 1151 references were identified, and 50 were eligible for final review. Economic burden was reported in most studies (n = 37) followed by treatment patterns (n = 26), and epidemiological (n = 25) and humanistic (n = 1) burdens. Prevalence of anemia varied largely (0-95%) based on the different definitions of anemia, and increased with CKD severity. Higher mortality was associated with erythropoiesis-stimulating agent (ESA) resistance and lower hemoglobin levels among patients treated with ESA. Drug dosage was the most reported economic burden (n = 33), followed by medical, and non-medical outcomes. Costs associated with anemia were considerable and depended on dialysis status and ESA treatment. Only one study reported data on quality of life, suggesting that further investigation on the humanistic burden of anemia in CKD is needed.

The relationship between haemoglobin level and type 1 diabetic nephropathy in Han patients in Anhui, China

BACKGROUND/AIM

Recent studies have shown that low haemoglobin (Hb) levels promote the progression of chronic kidney disease. This study assessed the relationship between Hb level and type 1 diabetic nephropathy (DN) in Han patients in Anhui, China.

METHODS

There was a total of 236 patients diagnosed with type 1 diabetes mellitus (T1DM) seen between January 2014 and December 2016 in our centre. Haemoglobin levels in patients with DN were compared with those without DN. The relationship between Hb level and the urinary albumin-creatinine ratio (ACR) was examined by Spearman's correlational analysis and multiple stepwise regression analysis. The binary logistic multivariate regression analysis was performed to analyse the correlated factors for type 1 DN, calculate the odds ratio (OR) and 95% confidence interval (CI). The predicting value of Hb level for DN was evaluated by area under receiver operation characteristic curve (AUROC) for discrimination and Hosmer-Lemeshow goodness-of-fit test for calibration.

RESULTS

The average Hb levels in the DN group (116.1 ± 20.8 g/L) were significantly lower than the non-DN group (131.9 ± 14.4 g/L), P < 0.001. Hb levels were independently correlated with the urinary ACR in multiple stepwise regression analysis. The logistic multivariate regression analysis showed that the Hb level (OR: 0.936, 95% CI: 0.910-0.963, P < 0.001) was inversely correlated with DN in patients with T1DM. In sub-analysis, low Hb level (Hb < 120 g/L in female, Hb < 130 g/L in male) was still negatively associated with DN in patients with T1DM. The AUROC was 0.721 (95% CI: 0.655-0.787) in assessing the discrimination of the Hb level for DN. The value of P was 0.593 in Hosmer-Lemeshow goodness-of-fit test.

CONCLUSIONS

In patients with T1DM, the Hb level is inversely correlated with urinary ACR and DN.

Epoetin alfa resistance in hemodialysis patients with chronic kidney disease: a longitudinal study

Anemia is an inevitable complication of hemodialysis, and the primary cause is erythropoietin deficiency. After diagnosis, treatment begins with an erythropoiesis-stimulating agent (ESA). However, some patients remain anemic even after receiving this medication. This study aimed to investigate the factors associated with resistance to recombinant human erythropoietin therapy with epoetin alfa (αEPO). We performed a prospective, longitudinal study of hemodialysis patients receiving treatment with αEPO at our reference hospital from July 2015 to June 2016. Clinical data was collected, and the response to αEPO treatment was evaluated using the erythropoietin resistance index (ERI). The ERI was defined as the weekly weight-adjusted αEPO dose (U/kg per week)/hemoglobin level (g/dL). A longitudinal linear regression model was fitted with random effects to verify the relationships between clinical and laboratory data and ERI. We enrolled 99 patients (average age, 45.7 (±17.6) years; male, 51.5%; 86.8% with hypertension). The ERI showed a significant positive association with serum ferritin and C-reactive protein, percentage interdialytic weight gain, and continuous usage of angiotensin receptor blocker (ARB) hypertension medication. The ERI was negatively associated with serum iron and albumin, age, urea reduction ratio, and body mass index. Our findings indicate that resistance to αEPO was related to a low serum iron reserve, an inflammatory state, poor nutritional status, and continuous usage of ARBs.

Hemoglobin target in children with chronic kidney disease: valuable new information

The international guideline from Kidney Disease: Improving Global Outcomes suggests a hemoglobin target of 11 to 12 g/dl for children with chronic kidney disease. However, information to support this proposal is very limited in the pediatric population. Because of controversy, the unmet need is the establishment of an appropriate target hemoglobin level in children with chronic kidney disease. Here, Rheault and colleagues provide valuable new information, reporting the association of hemoglobin levels with cardiovascular morbidity in pediatric hemodialysis patients.

Disease or adaptation: another look at the practice of medicine

The practice of medicine has changed considerably over the past few decades and is now focusing more and more on early intervention strategies. As a result, we tend to consider pre-symptomatic abnormalities, however small, already as a potential target for treatment. In this viewpoint, we argue that we should put more emphasis on pathophysiological thinking as many of the so-called early abnormalities may, in fact, reflect adaptive mechanisms rather than disease. This view should influence medical care and education, emphasizing the importance of knowledge of pathophysiology.

Fibroblast Growth Factor 23 and Anemia in the Chronic Renal Insufficiency Cohort Study

BACKGROUND AND OBJECTIVES

Anemia is an early complication of CKD that is associated with increased morbidity and mortality. Prior data show associations between abnormal mineral metabolism markers and decreased erythropoiesis. However, few studies have investigated elevated fibroblast growth factor 23 as a risk factor for the development of anemia in patients with CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We conducted a prospective cohort study of 3869 individuals with mild to severe CKD enrolled in the Chronic Renal Insufficiency Cohort Study between 2003 and 2008 and followed through 2013. We hypothesized that elevated baseline fibroblast growth factor 23 levels are associated with prevalent anemia, decline in hemoglobin over time, and development of incident anemia, defined as serum hemoglobin level <13 g/dl in men, serum hemoglobin level <12 g/dl in women, or use of erythropoietin stimulating agents.

RESULTS

In the 1872 of 3869 individuals who had prevalent anemia at baseline, mean age was 58 (11) years old, and mean eGFR was 39 (13) ml/min per 1.73 m2. Higher levels of fibroblast growth factor 23 were significantly associated with prevalent anemia (odds ratio per 1-SD increase in natural log-transformed fibroblast growth factor 23, 1.39; 95% confidence interval, 1.26 to 1.52), decline in hemoglobin over 4 years, and risk of incident anemia (hazard ratio per 1-SD increase in natural log-transformed fibroblast growth factor 23, 1.13; 95% confidence interval, 1.04 to 1.24; quartile 4 versus quartile 1: hazard ratio, 1.59; 95% confidence interval, 1.19 to 2.11) independent of demographic characteristics, cardiovascular disease risk factors, CKD-specific factors, and other mineral metabolism markers. The results of our prospective analyses remained unchanged after additional adjustment for time-varying eGFR.

CONCLUSIONS

Elevated fibroblast growth factor 23 is associated with prevalent anemia, change in hemoglobin over time, and development of anemia. Future studies are needed to elucidate the mechanisms for these associations.

Cyanate improves insulin sensitivity and hepatic steatosis in normal and high fat-fed mice: Anorexic and antioxidative effects

Obesity is an important contributing factor to progression of chronic kidney disease. Cyanate, known as uremic toxin, is an electrophile produced spontaneously from urea or by myeloperoxidase-catalyzed oxidation of thiocyanate. Herein, we explored metabolic effects of cyanate in normal chow diet (NCD)- and high fat diet (HFD)-fed mice. Mice were treated with cyanate (1 mg/mL in drinking water) and fed NCD or HFD. Peritoneal glucose tolerance test (PGTT) and insulin tolerance test (ITT) were performed. Blood urea nitrogen (BUN) and creatinine concentrations were determined. Kidney and liver tissues were analyzed for reactive oxygen species (ROS) and lipid accumulations. Human albumin was carbamylated and evaluated for ROS scavenging activities. Contrary to our expectations, we found that cyanate treatment improved increased insulin sensitivity and alleviated hepatic steatosis in NCD- and HFD-fed mice. PGTT and ITT revealed faster and immediate glucose clearance in cyanate-treated NCD- and HFD-fed mice. Histological analysis of kidney and serum levels of BUN and creatinine showed no significant differences between cyanate-treated and control mice groups. Cyanate treatment reduced appetite and body weight in both NCD- and HFD-fed mice groups. Cyanate also decreased lipid peroxidation levels in the sera and the kidney, attenuated ROS levels in the kidney, which lead us to the findings that cAlb significantly reduced ROS levels compared to Alb in Caki-1 kidney and human umbilical vein endothelial cells. The results in this study may indicate that cyanate improves insulin sensitivity and hepatic steatosis possibly via exerting anorexic and antioxidative effects.

The effects of probiotic supplement on hemoglobin in chronic renal failure patients under hemodialysis: A randomized clinical trial

Background:

Chronic inflammation is one of the causes of anemia in chronic renal failure patients under hemodialysis. Probiotics probably establish a balance between pro- and anti-inflammatory cytokines. The study was conducted to determine the effects of probiotic supplementation on hemoglobin (Hb) in hemodialysis patients.

Materials and Methods:

A parallel clinical trial was conducted in which patients were randomly allocated into two groups. The intervention group (n = 18) was given a 500 mg probiotic supplement (a capsule) every day whereas the control group (n = 18) received placebo (a capsule), both for 3 months. Hb levels and C-reactive protein (CRP) levels were measured for three periods. The data were analyzed in SPSS-16 using statistical tests including the t-test and repeated-measures ANOVA.

Results:

In the probiotic supplementation group, the mean Hb was 9.22 ± 1.04 mg/dl before the intervention and reached 10.85 ± 1.177 mg/dl afterward, while in the placebo group, the mean Hb level was 9.38 ± 0.97 mg/dl before the intervention and reached 10.03 ± 1.97 mg/dl afterward (P > 0.05). During the study, the placebo caused to increase of Hb temporary, but in longer term, the effect of probiotic was more manifested. Hb levels increased in both groups although the change was not statistically significant (P > 0.05). The findings showed no significant differences between the two groups in either the pre- or post-intervention CRP levels (P = 0.239).

Conclusion:

Probiotic supplementation decreased Hb fluctuations in hemodialysis patients but did not result in a significant increase in Hb levels. Similar studies are therefore recommended to be conducted with a prolonged duration of the study or an increased probiotic dose with larger sample size to complete the results of the present study.

Applying data mining techniques to determine important parameters in chronic kidney disease and the relations of these parameters to each other

Introduction: Chronic kidney disease (CKD) includes a wide range of pathophysiological processes which will be observed along with abnormal function of kidneys and progressive decrease in glomerular filtration rate (GFR). According to the definition decreasing GFR must have been present for at least three months. CKD will eventually result in end-stage kidney disease. In this process different factors play role and finding the relations between effective parameters in this regard can help to prevent or slow progression of this disease. There are always a lot of data being collected from the patients’ medical records. This huge array of data can be considered a valuable source for analyzing, exploring and discovering information.

Objectives: Using the data mining techniques, the present study tries to specify the effective parameters and also aims to determine their relations with each other in Iranian patients with CKD.

Material and Methods: The study population includes 31996 patients with CKD. First, all of the data is registered in the database. Then data mining tools were used to find the hidden rules and relationships between parameters in collected data.

Results: After data cleaning based on CRISP-DM (Cross Industry Standard Process for Data Mining) methodology and running mining algorithms on the data in the database the relationships between the effective parameters was specified.

Conclusion: This study was done using the data mining method pertaining to the effective factors on patients with CKD.

Study of association between interleukin-17 and interferon-gamma and recombinant human erythropoietin dose in patients undergoing peritoneal dialysis

BACKGROUND

A common complication in patients undergoing peritoneal dialysis (PD) is a chronic inflammatory state and anemia that can be treating by recombinant human erythropoietin (rHuEPO). Higher required dose of rHuEPO could be expected in patients with higher cytokine levels. Additionally, it is known that peritoneal inflammation can be correlated with systemic inflammation and this could contribute to the compromised rHuEPO required dose in anemic patients with end stage renal disease (ESRD). Thus, the current study aimed to evaluate the association between levels of systemic and local interferon (IFN)-γ, interleukin (IL)-17 and other cytokines and the dose of rHuEPO used by patients undergoing PD for the correction of anemia.

METHODS

Thirty-one patients under PD using rHuEPO were evaluated in this cross-sectional study. Plasma and dialysate levels of IL-2, IL-4, IL-6, IL-10, IL-17, tumour necrosis factor (TNF)-α and IFN-γ were determined using the Cytometric Bead Array TM kit (CBA; BD Bioscences, San Jose, CA). The relation between the levels of each cytokine levels and the tertiles of rHuEPO were plotted on box-plot graphics and then the medians of interleukins levels were compared by median comparison test. The significance level adopted was 5% and the analysis was performed by the softwares STATA (version 12.0) and GraphPad Prism 3.0.

RESULTS

The median of IL-17 and IFN-γ plasma levels were significant higher in the group with higher rHuEPO dosage. However, this association was not observed in the dialysate levels, as well as was not observed a relationship between the other plasma and dialysate cytokines evaluated in this study and the dose of rHuEPO.

CONCLUSIONS

Our study found increased IL-17 and IFN-γ plasma, but no dialysate levels, in patients receiving higher doses of rHuEPO, suggesting may exist a relationship between systemic inflammation of ESRD, and the necessary levels of rHuEPO for the correction of anemia in these patients.

Mortality after Renal Allograft Failure and Return to Dialysis

INTRODUCTION

The outcomes of patients who fail their kidney transplant and return to dialysis (RTD) has not been investigated in a nationally representative sample. We hypothesized that variations in management of transplant chronic kidney disease stage 5 leading to kidney allograft failure (KAF) and RTD, such as access, nutrition, timing of dialysis, and anemia management predict long-term survival.

METHODS

We used an incident cohort of patients from the United States Renal Data System who initiated hemodialysis between January 1, 2003 and December 31, 2008, after KAF. We used Cox regression analysis for statistical associations, with mortality as the primary outcome.

RESULTS

We identified 5,077 RTD patients and followed them for a mean of 30.9 ± 22.6 months. Adjusting for all possible confounders at the time of RTD, the adjusted hazards ratio (AHR) for death was increased with lack of arteriovenous fistula at initiation of dialysis (AHR 1.22, 95% CI 1.02-1.46, p = 0.03), albumin <3.5 g/dL (AHR 1.33, 95% CI 1.18-1.49, p = 0.0001), and being underweight (AHR 1.30, 95% CI 1.07-1.58, p = 0.006). Hemoglobin <10 g/dL (AHR 0.96, 95% CI 0.86-1.06, p = 0.46), type of insurance, and zip code-based median household income were not associated with higher mortality. Glomerular filtration rate <10 mL/min/1.73 m2 at time of dialysis initiation (AHR 0.83, 95% CI 0.75-0.93, p = 0.001) was associated with reduction in mortality.

CONCLUSIONS

Excess mortality risk observed in patients starting dialysis after KAF is multifactorial, including nutritional issues and vascular access. Adequate preparation of patients with failing kidney transplants prior to resuming dialysis may improve outcomes.

Lack of hepcidin ameliorates anemia and improves growth in an adenine-induced mouse model of chronic kidney disease

Growth delay is common in children with chronic kidney disease (CKD), often associated with poor quality of life. The role of anemia in uremic growth delay is poorly understood. Here we describe an induction of uremic growth retardation by a 0.2% adenine diet in wild-type (WT) and hepcidin gene (Hamp) knockout (KO) mice, compared with their respective littermates fed a regular diet. Experiments were started at weaning (3 wk). After 8 wk, blood was collected and mice were euthanized. Adenine-fed WT mice developed CKD (blood urea nitrogen 82.8 ± 11.6 mg/dl and creatinine 0.57 ± 0.07 mg/dl) and were 2.1 cm shorter compared with WT controls. WT adenine-fed mice were anemic and had low serum iron, elevated Hamp, and elevated IL6 and TNF-α. WT adenine-fed mice had advanced mineral bone disease (serum phosphorus 16.9 ± 3.1 mg/dl and FGF23 204.0 ± 115.0 ng/ml) with loss of cortical and trabecular bone volume seen on microcomputed tomography. Hamp disruption rescued the anemia phenotype resulting in improved growth rate in mice with CKD, thus providing direct experimental evidence of the relationship between Hamp pathway and growth impairment in CKD. Hamp disruption ameliorated CKD-induced growth hormone-insulin-like growth factor 1 axis derangements and growth plate alterations. Disruption of Hamp did not mitigate the development of uremia, inflammation, and mineral and bone disease in this model. Taken together, these results indicate that an adenine diet can be successfully used to study growth in mice with CKD. Hepcidin appears to be related to pathways of growth retardation in CKD suggesting that investigation of hepcidin-lowering therapies in juvenile CKD is warranted.

Association between Vitamin D Deficiency and Anemia in Patients with End-Stage Renal Disease: A Cross-Sectional Study

PURPOSE

Despite new treatment strategies, anemia remains the most prevalent complication in patients with end-stage renal disease (ESRD). We investigated whether 25-hydroxyvitamin D [25(OH)D3] deficiency was associated with anemia in ESRD patients.

MATERIALS AND METHODS

We reviewed the medical records of 410 ESRD patients who had undergone renal transplantation (RTx) at Yonsei University Health System and who had 25(OH)D3 levels measured at the time of RTx. Patients were divided into two groups based on baseline 25(OH)D3 concentrations: group 1, 25(OH)D3 levels <10 ng/mL; and group 2, 25(OH)D3 levels ≥10 ng/mL.

RESULTS

Using multivariate regression models, 25(OH)D3, age, and erythrocyte-stimulating agent (ESA) dose were found to be significantly associated with hemoglobin (Hb) levels [25(OH)D3: β=0.263, p<0.001; age: β=0.122, p=0.010; ESA dose: β=-0.069, p=0.005]. In addition, logistic regression analysis revealed that patients in group 1 had a significantly higher risk for developing anemia (Hb level <10 g/dL) compared to group 2 patients, even after adjusting for potential risk factors for anemia (odds ratio=3.857; confidence interval=1.091-13.632; p=0.036).

CONCLUSION

25(OH)D3 deficiency was significantly associated with anemia in patients with ESRD. Randomized controlled trials are needed to determine whether vitamin D supplementation can improve anemia in these patients.

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.

Carbamylated Erythropoietin Outperforms Erythropoietin in the Treatment of AKI-on-CKD and Other AKI Models

Erythropoietin (EPO) may be a beneficial tissue-protective cytokine. However, high doses of EPO are associate with adverse effects, including thrombosis, tumor growth, and hypertension. Carbamylated erythropoietin (CEPO) lacks both erythropoietic and vasoconstrictive actions. In this study, we compared the renoprotective, hemodynamic, and hematologic activities and survival effects of identical EPO and CEPO doses in rat models of clinically relevant AKI presentations, including ischemia-reperfusion-induced AKI superimposed on CKD (5000 U/kg EPO or CEPO; three subcutaneous injections) and ischemia-reperfusion-induced AKI in old versus young animals and male versus female animals (1000 U/kg EPO or CEPO; three subcutaneous injections). Compared with EPO therapy, CEPO therapy induced greater improvements in renal function and body weight in AKI on CKD animals, with smaller increases in hematocrit levels and similarly improved survival. Compared with EPO therapy in the other AKI groups, CEPO therapy induced greater improvements in protection and recovery of renal function and survival, with smaller increases in systolic BP and hematocrit levels. Overall, old or male animals had more severe loss in kidney function and higher mortality rates than young or female animals, respectively. Notably, mRNA and protein expression analyses confirmed the renal expression of the heterodimeric EPO receptor/CD131 complex, which is required for the tissue-protective effects of CEPO signaling. In conclusion, CEPO improves renal function, body and kidney weight, and survival in AKI models without raising hematocrit levels and BP as substantially as EPO. Thus, CEPO therapy may be superior to EPO in improving outcomes in common forms of clinical AKI.

Performance of a Predictive Model for Long-Term Hemoglobin Response to Darbepoetin and Iron Administration in a Large Cohort of Hemodialysis Patients

Anemia management, based on erythropoiesis stimulating agents (ESA) and iron supplementation, has become an increasingly challenging problem in hemodialysis patients. Maintaining hemodialysis patients within narrow hemoglobin targets, preventing cycling outside target, and reducing ESA dosing to prevent adverse outcomes requires considerable attention from caregivers. Anticipation of the long-term response (i.e. at 3 months) to the ESA/iron therapy would be of fundamental importance for planning a successful treatment strategy. To this end, we developed a predictive model designed to support decision-making regarding anemia management in hemodialysis (HD) patients treated in center. An Artificial Neural Network (ANN) algorithm for predicting hemoglobin concentrations three months into the future was developed and evaluated in a retrospective study on a sample population of 1558 HD patients treated with intravenous (IV) darbepoetin alfa, and IV iron (sucrose or gluconate). Model inputs were the last 90 days of patients’ medical history and the subsequent 90 days of darbepoetin/iron prescription. Our model was able to predict individual variation of hemoglobin concentration 3 months in the future with a Mean Absolute Error (MAE) of 0.75 g/dL. Error analysis showed a narrow Gaussian distribution centered in 0 g/dL; a root cause analysis identified intercurrent and/or unpredictable events associated with hospitalization, blood transfusion, and laboratory error or misreported hemoglobin values as the main reasons for large discrepancy between predicted versus observed hemoglobin values. Our ANN predictive model offers a simple and reliable tool applicable in daily clinical practice for predicting the long-term response to ESA/iron therapy of HD patients.

Targeting EPO and EPO receptor pathways in anemia and dysregulated erythropoiesis

INTRODUCTION

Recombinant human erythropoietin (rhEPO) is a first-line therapeutic for the anemia of chronic kidney disease, cancer chemotherapy, AIDS (Zidovudine therapy), and lower-risk myelodysplastic syndrome. However, rhEPO frequently elevates hypertension, is costly, and may affect cancer progression. Potentially high merit therefore exists for defining new targets for anti-anemia agents within erythropoietin (EPO) and EPO receptor (EPOR) regulatory circuits.

AREAS COVERED

EPO production by renal interstitial fibroblasts is subject to modulation by several regulators of hypoxia-inducible factor 2a (HIF2a) including Iron Response Protein-1, prolyl hydroxylases, and HIF2a acetylases, each of which holds potential as anti-anemia drug targets. The cell surface receptor for EPO (EPOR) preassembles as a homodimer, together with Janus Kinase 2 (JAK2), and therefore it remains attractive to develop novel agents that trigger EPOR complex activation (activating antibodies, mimetics, small-molecule agonists). Additionally, certain downstream transducers of EPOR/JAK2 signaling may be druggable, including Erythroferrone (a hepcidin regulator), a cytoprotective Spi2a serpin, and select EPOR-associated protein tyrosine phosphatases.

EXPERT OPINION

While rhEPO (and biosimilars) are presently important mainstay erythropoiesis-stimulating agents (ESAs), impetus exists for studies of novel ESAs that fortify HIF2a's effects, act as EPOR agonists, and/or bolster select downstream EPOR pathways to erythroid cell formation. Such agents could lessen rhEPO dosing, side effects, and/or costs.

Time Savings with Once-Monthly C.E.R.A.: A Time and Motion Study Conducted in 13 Haemodialysis Centres in Italy

BACKGROUND

We sought to document the time required by health care professionals to administer erythropoiesis-stimulating agents (ESAs) and continuous erythropoiesis receptor activator (C.E.R.A.) in the management of renal anaemia.

METHODS

A Time and Motion study was conducted in 13 centres in Italy. The time spent on preparation, distribution, and injection for both ESA and C.E.R.A. groups was measured. A multilevel model was run to account for the centre-clustering effect.

RESULTS

The average number of ESA injections/patient/year was 89. The average uptake of C.E.R.A. was 26%. The average time per session was 1.54 min for ESA (95% CI 1.21-1.86) vs. 1.64 min for C.E.R.A. (95% CI 1.31-1.97). Estimated time/patient/year was 137 min for ESA and 20 min for C.E.R.A. Assuming a 100% uptake of C.E.R.A., annual time savings/centre would be 84% (194 h).

CONCLUSIONS

Substantial annual time savings on frequent anaemia management-related tasks were found when a switchover was made from ESAs to C.E.R.A.

Pentoxifylline for Anemia in Chronic Kidney Disease: A Systematic Review and Meta-Analysis

BACKGROUND

Pentoxifylline (PTX) is a promising therapeutic approach for reducing inflammation and improving anemia associated to various systemic disorders. However, whether this agent may be helpful for anemia management also in CKD patients is still object of debate.

STUDY DESIGN

Systematic review and meta-analysis.

POPULATION

Adults with CKD (any KDOQI stage, including ESKD patients on regular dialysis) and anemia (Hb<13 g/dL in men or < 12 g/dL in women).

SEARCH STRATEGY AND SOURCES

Cochrane CENTRAL, EMBASE, Ovid-MEDLINE and PubMed were searched for studies providing data on the effects of PTX on anemia parameters in CKD patients without design or follow-up restriction.

INTERVENTION

PTX derivatives at any dose regimen.

OUTCOMES

Hemoglobin, hematocrit, ESAs dosage and resistance (ERI), iron indexes (ferritin, serum iron, TIBC, transferrin and serum hepcidin) and adverse events.

RESULTS

We retrieved 11 studies (377 patients) including seven randomized controlled trials (all comparing PTX to placebo or standard therapy) one retrospective case-control study and three prospective uncontrolled studies. Overall, PTX increased hemoglobin in three uncontrolled studies but such improvement was not confirmed in a meta-analysis of seven studies (299 patients) (MD 0.12 g/dL, 95% CI -0.22 to 0.47). Similarly, there were no conclusive effects of PTX on hematocrit, ESAs dose, ferritin and TSAT in pooled analyses. Data on serum iron, ERI, TIBC and hepcidin were based on single studies. No evidence of increased rate of adverse events was also noticed.

LIMITATIONS

Small sample size and limited number of studies. High heterogeneity among studies with respect to CKD and anemia severity, duration of intervention and responsiveness/current therapy with iron or ESAs.

CONCLUSIONS

There is currently no conclusive evidence supporting the utility of pentoxifylline for improving anemia control in CKD patients. Future trials designed on hard, patient-centered outcomes with larger sample size and longer follow-up are advocated.

Clinical impact of the ERBP Working Group 2010 Recommendations for the anemia management in chronic kidney disease not on dialysis: ACERCA study

BACKGROUND AND OBJECTIVE

The Anemia Working Group of ERBP in 2010 recommended a target hemoglobin (Hb) level in the range of 11-12 g/dL, without intentionally exceeding 13 g/dL during the treatment with erythropoiesis stimulating agents (ESAs). This study evaluated if there was a clinical impact of this statement in the anemia management of chronic kidney disease (CKD) patients treated with ESAs not on dialysis in routine clinical practice in Spain.

METHODS

This was an observational and cross-sectional study carried out in CKD patients not on dialysis in Spain who initiated ESA treatment (naïve), or were shifted from a previous ESA to another ESAs (converted) since January 2011.

RESULTS

Of 441 patients evaluated, 67.6% were naïve and 32.4% were converted. At the study visit, 42.5% of naïve patients achieved the Hb target of 11-12 g/dL, with a mean Hb of 11.3±1.3 g/dL (vs 10.1±0.9 g/dL at the start of ESA therapy). Only 35.3% of converted patients maintained Hb levels within the recommended target at the study visit. Yet, 8.2% of naïve patients and 7.9% of those converted had Hb levels >13 g/dL. Hb levels were similar across subgroups of patients, regardless of the presence of significant comorbidities.

CONCLUSIONS

Anemia management in CKD patients treated with ESAs by Spanish nephrologists seems to be aimed at preventing Hb levels <11 g/dL, while <50% of patients were within the narrow recommended Hb target range. This, together with the lack of individualization in Hb targets according to patients' comorbidities show that there is still room for improvement in renal anemia management in the clinical setting.

Can Serum Gdf-15 be Associated with Functional Iron Deficiency in Hemodialysis Patients?

Functional iron deficiency (FID) incidence is gradually increasing in hemodialysis (HD) patients. Recently, high levels of GDF-15 supressed the iron regulatory protein hepcidin and GDF-15 expression increased in iron-deficient patients. The relationship between FID, GDF-15, and hepcidin is currently unknown. The present study aimed to evaluate the association between GDF-15, hepcidin, and FID in chronic HD patients. Serum GDF-15 and hepcidin concentrations were measured in 105 HD patients and 40 controls. FID is defined as serum ferritin >800 ng/mL, TSAT <25 %, Hb levels <11 g/dL, and reticulocyte haemoglobin content (CHr) <29 pg. Serum GDF-15 and hepcidin levels were increased significantly in HD patients with FID, compared to HD patients without anemia and controls. GDF-15 correlated with ferritin, hepcidin, and CRP in the entire cohort. GDF-15 was related to ferritin and CRP in HD patients with FID. GDF-15 is better diagnostic marker than hepcidin for detection of FID [AUC = 0.982 (0.013) versus AUC = 0.921 (0.027); P = 0.0324]. GDF-15 appears to be a promising tool for detection of FID. High levels of ferritin and CRP correlated with GDF-15. Our results support GDF-15 as a new mediator of FID via hepcidin, chronic inflammation, or unknown pathways.

Effect on outcomes and exercise performance of anemia in patients with aortic stenosis who underwent transcatheter aortic valve replacement

The objectives of this study were to determine the causes and impact of anemia and hemoglobin level on functional status, physical performance, and quality of life in the preprocedural evaluation and follow-up of transcatheter aortic valve replacement (TAVR) candidates. A total of 438 patients who underwent TAVR were included. Anemia was defined as a hemoglobin level <12 g/dl in women and <13 g/dl in men. Before TAVR, anemia was encountered in 282 patients (64.4%). A potential treatable cause of anemia was detected in 90.4% of patients and was attributed to iron deficiency in 53% of them. The occurrence of anemia was an independent predictor of poorer performance in the 6-minute walk test (6MWT), a lower Duke Activity Status Index score, and Kansas City Cardiomyopathy Questionnaires overall, clinical, and social limitation scores (p <0.05 for all). A lower hemoglobin level was associated with a higher prevalence of New York Heart Association class III to IV (p <0.001) and correlated negatively with the results of all functional tests (p <0.02 for all). At follow-up, anemia was found in 62% of patients and was associated with poorer performance in the 6MWT (p = 0.023). A lower hemoglobin level after TAVR was a predictor of poorer New York Heart Association class (p = 0.020) and correlated negatively with the distance walked in the 6MWT (r = -0.191, p = 0.004) and Duke Activity Status Index score (r = -0.158, p = 0.011) at 6-month follow-up. In conclusion, anemia was very common in TAVR candidates and was attributed to iron deficiency in more than half of them. The presence of anemia and lower hemoglobin levels determined poorer functional status before and after the TAVR procedure. These results highlight the importance of implementing appropriate measures for the diagnosis and treatment of this frequent co-morbidity to improve both the accuracy of preprocedural evaluation and outcomes of TAVR candidates.

Optimal hemoglobin level for anemia treatment in a cohort of hemodialysis patients

BACKGROUND

Anemia is a major risk factor that contributes to mortality in patients with chronic kidney disease. There is controversy over the optimal hemoglobin (Hb) target in these patients. This study investigated the association between Hb level and mortality in a cohort of hemodialysis (HD) patients in Korea.

METHODS

This study was a multicenter prospective observational study of maintenance HD patients that was performed for 5 years in western Seoul, Korea. Three hundred and sixty-two participants were enrolled. Laboratory values and mortality were accessed every 6 months. Repeated measures of laboratory values in each interval were averaged to obtain one semiannual mean value. The Hb values were divided into six groups: (1) Hb<9 g/dL; (2) 9 g/dL≤Hb<10 g/dL; (3) 10 g/dL≤Hb<11 g/dL; (4) 11 g/dL≤Hb<12 g/dL; (5) 12 g/dL≤Hb<13 g/dL; and (6) Hb≥13 g/dL. We analyzed the odds ratio for all-cause mortality, based on the Hb group, and adjusted for demographics and various laboratory values. Statistics were performed with SAS, version 9.1 software (SAS Institute Inc., Cary, NC, USA).

RESULTS

Mortality odds ratios relative to the reference group (10-11 g/dL) in the fully adjusted model were 3.61 for<9 g/dL; 3.17 for 9-10 g/dL(⁎); 4.65 for 11-12 g/dL(⁎); 5.50 for 12-13 g/dL(⁎); and 2.05 for≥13 g/dL ((⁎) indicates P<0.05).

CONCLUSION

In this study, a Hb level of 10-11 g/dL was associated with the lowest mortality among the groups with Hb level<13 g/dL. Larger interventional trials are warranted to determine the optimal Hb target for Korean HD patients.

Iron supplementation and mortality in incident dialysis patients: an observational study

BACKGROUND

Studies on the association between iron supplementation and mortality in dialysis patients are rare and conflicting.

METHODS

In our observational single-center cohort study (INVOR study) we prospectively studied 235 incident dialysis patients. Time-dependent Cox proportional hazards models using all measured laboratory values for up to 7.6 years were applied to study the association between iron supplementation and all-cause mortality, cardiovascular and sepsis-related mortality. Furthermore, the time-dependent association of ferritin levels with mortality in patients with normal C-reactive protein (CRP) levels (<0.5 mg/dL) and elevated CRP levels (≧0.5 mg/dL) was evaluated by using non-linear P-splines to allow flexible modeling of the association.

RESULTS

One hundred and ninety-one (81.3%) patients received intravenous iron, 13 (5.5%) patients oral iron, whereas 31 (13.2%) patients were never supplemented with iron throughout the observation period. Eighty-two (35%) patients died during a median follow-up of 34 months, 38 patients due to cardiovascular events and 21 patients from sepsis. Baseline CRP levels were not different between patients with and without iron supplementation. However, baseline serum ferritin levels were lower in patients receiving iron during follow up (median 93 vs 251 ng/mL, p<0.001). Iron supplementation was associated with a significantly reduced all-cause mortality [HR (95%CI): 0.22 (0.08-0.58); p = 0.002] and a reduced cardiovascular and sepsis-related mortality [HR (95%CI): 0.31 (0.09-1.04); p = 0.06]. Increasing ferritin concentrations in patients with normal CRP were associated with a decreasing mortality, whereas in patients with elevated CRP values ferritin levels>800 ng/mL were linked with increased mortality.

CONCLUSIONS

Iron supplementation is associated with reduced all-cause mortality in incident dialysis patients. While serum ferritin levels up to 800 ng/mL appear to be safe, higher ferritin levels are associated with increased mortality in the setting of concomitant inflammation.

Plasma ascorbic acid concentrations in prevalent patients with end-stage renal disease on hemodialysis

OBJECTIVE

To determine the prevalence of vitamin C (ascorbic acid [AA]) deficiency in patients with end-stage renal disease, the effect of supplemental AA on plasma AA concentrations, and the extrinsic and intrinsic factors that affect plasma AA concentrations in this patient population.

DESIGN

In study 1, we compared the effect of hemodialysis (HD) on plasma AA concentrations between patients with low and high pre-HD AA concentrations. In study 2, we analyzed kinetic and nonkinetic factors for their association with increased plasma AA concentrations in patients on maintenance HD. Study 1 was performed in a single outpatient HD clinic in Cherry Hill, New Jersey. Study 2 was performed in 4 outpatient HD clinics in Southern New Jersey.

SUBJECTS AND INTERVENTION

In study 1, we collected plasma samples from 8 adult patients on maintenance HD at various time points around their HD treatment and assayed them for AA concentration. In study 2, we enrolled 203 adult patients and measured pre-HD plasma AA concentrations. We ascertained supplemental AA use and assessed dietary AA intake.

MAIN OUTCOME MEASURE

In study 1, plasma AA concentrations were compared during the intradialytic and interdialytic period. In study 2, pre-HD plasma AA concentrations were correlated with supplement use and demographic factors.

RESULTS

Study 1 showed that over the course of a single HD treatment, the plasma AA concentration decreased by a mean (±standard deviation) of 60% (±6.6). In study 2, the median pre-HD plasma AA concentration was 15.7 μM (interquartile range, 8.7-66.8) in patients who did not take a supplement and 50.6 μM (interquartile range, 25.1-88.8) in patients who did take a supplement (P < .001). Supplement use, increasing age, and diabetes mellitus were associated with a pre-HD plasma AA concentration ≥30 μM.

CONCLUSION

HD depletes plasma AA concentrations, and AA supplementation allows patients to achieve higher plasma AA concentrations.

Preservation of anemia control and weekly ESA dosage after conversion from PEG-Epoetin beta to darbepoetin alfa in adult hemodialysis patients: the TRANSFORM study

Introduction

There is scant real-world information on switching treatment for anemia associated with chronic kidney disease (CKD) from methoxy polyethylene glycol-epoetin beta (PEG-Epo) to darbepoetin alfa (DA). TRANSFORM was a multi-center, observational study designed to describe the time course of hemoglobin (Hb) concentration (primary outcome measure) and other parameters of clinical management of anemia in European hemodialysis patients in clinical practice before and after a switch from PEG-Epo to DA.

Methods

Eligible subjects were adult patients with CKD dialyzed at European dialysis centers for ≥26 weeks and treated with PEG-Epo for ≥14 weeks immediately prior to being switched to DA and no earlier than January 2011. Erythropoiesis-stimulating agent doses and Hb values were recorded for the 14-week pre-switch and 26-week post-switch periods.

Results

Of the 1,027 eligible patients enrolled at 42 hemodialysis centers in 7 European countries, 785 were included in analyses. Mean (95% confidence interval [CI]) Hb was generally stable: 11.19 (11.11, 11.26), 11.48 (11.40, 11.57), and 11.29 (11.20, 11.37) g/dL at month −1 pre-switch and months 3 and 6 post-switch, respectively. The geometric mean (95% CI) PEG-Epo dose at month −1 was 27.4 (26.0, 28.8) µg/week; DA dose was 29.4 (27.9, 30.9), 23.3 (21.9, 24.9), and 25.6 (24.1, 27.1) µg/week at months 1, 4, and 6, respectively. The geometric mean (95% CI) dose ratio at switching was 1.06 (1.01, 1.11). When stratifying by dose-ratio categories <0.8, 0.8–1.2, and >1.2 at switching, mean DA dose and Hb converged within narrow ranges by month 6 post-switch: 23.9–27.0 µg/week and 11.1–11.5 g/dL, respectively. Hb excursions <10 g/dL were less frequent post-switch versus pre-switch.

Conclusion

Mean Hb values remained within a narrow range following switching from PEG-Epo to DA in this population of hemodialysis patients. Time trends of mean Hb and DA dose indicate that physicians titrated DA doses post-switch, to attain Hb concentrations comparable to those attained pre-switch with PEG-Epo.

Funding

Amgen (Europe) GmbH, Zug, Switzerland.

Electronic supplementary material

The online version of this article (doi:10.1007/s12325-014-0161-5) contains supplementary material, which is available to authorized users.

Resistance to erythropoiesis-stimulating agents is associated with arterial microcalcification in early hemodialysis patients

The aim of this study was to evaluate the relationship between arterial microcalcification (AMiC) and erythropoiesis-stimulating agents (ESA) hyporesponsiveness in hemodialysis patients. The presence of AMiC was confirmed by pathologic examination of von Kossa-stained arterial specimens acquired during vascular access surgery. We assessed the ESA hyporesponsiveness index (EHRI), defined as the weekly ESA dose per kilogram body weight divided by the hemoglobin level. AMiC was detected in 33 (40.2%) of 82 patients. Patients with diabetes had a higher incidence of AMiC than patients without diabetes. The serum levels of albumin and cholesterol were higher in patients without AMiC than in patients with AMiC. The serum levels of intact parathyroid hormone were lower in patients with AMiC than in patients without AMiC. The serum levels of phosphate and calcium-phosphorus product did not differ between the two groups. The mean EHRI value was higher in patients with AMiC than in patients without AMiC. In multivariate analyses, ESA hyporesponsiveness and diabetes showed a significant association with AMiC. In conclusion, ESA hyporesponsiveness may be a clinical relevant parameters related to AMiC in hemodialysis patients.

Inflammation, high ferritin, and erythropoietin resistance in indigenous maintenance hemodialysis patients from the Top End of Northern Australia

Use of erythropoiesis-stimulating agents (ESAs) has improved the management of anemia in patients on maintenance hemodialysis (MHD). Iron deficiency and inflammation cause ESAs resistance and are both common among indigenous people of Northern Australia. As part of quality assurance in our Renal Anaemia Management program, we observed that there was use of higher doses of ESAs and adjuvant iron therapy in our MHD patients. This study aimed to explore the relationship among iron studies, inflammation, ESA responsiveness, and ESAs and iron requirements in indigenous patients on MHD from the Top End of Northern Australia. We performed a retrospective cohort analysis of anemia management in a cohort of our patients on MHD. We extracted data for 178 indigenous and 19 non-indigenous patients from 1 March 2009 to 28 February 2010 from the Renal Anaemia Management database, which collects data prospectively in MHD patients. Ninety-nine percent of the whole sample had a ferritin level above the international guidelines threshold of >500 µg/L. Indigenous patients had higher ferritin (1534 ± 245.5 µg/L vs. 1013 ± 323.3 µg/L, P = 0.002). C-reactive protein (CRP) was high in 56.9% of the total cohort. One hundred percent of those with normal CRP had high ferritin (>500 µg/L). C-reactive protein was higher in indigenous than in non-indigenous patients. Erythropoiesis-stimulating agents hyporesponsiveness was higher in indigenous patients (P < 0.0001). There was no significant difference in ESAs hyporesponsiveness among different levels of CRP (P = 0.116), ferritin (P = 0.408), and transferrin saturation (P = 0.503). Indigenous patients required higher total iron dose (2820.30 [2000-4350] vs. 2336.12 [1912-2900], P = 0.02). There was no significant relationship between the high ferritin and CRP. In indigenous dialysis patients, iron therapy and ESAs use are higher. The high iron use is due to a lack of published evidence to guide the administration of iron in patients with high ferritin. The high ferritin and ESAs resistance could not be fully explained by inflammation and need further evaluation. Further studies are required to determine the safe use of iron and management of ESAs resistance in our hemodialysis population.

Association between hemoglobin variability, serum ferritin levels, and adverse events/mortality in maintenance hemodialysis patients

In recent times, therapy for renal anemia has changed dramatically in that iron administration has increased and doses of erythropoiesis-stimulating agents (ESAs) have decreased. Here we used a prospective, observational, multicenter design and measured the serum ferritin and hemoglobin levels every 3 months for 2 years in 1086 patients on maintenance hemodialysis therapy. The associations of adverse events with fluctuations in ferritin and hemoglobin levels and ESA and iron doses were measured using a Cox proportional hazards model for time-dependent variables. The risks of cerebrovascular and cardiovascular disease (CCVD), infection, and hospitalization were higher among patients who failed to maintain a target-range hemoglobin level and who exhibited high-amplitude fluctuations in hemoglobin compared with patients who maintained a target-range hemoglobin level. Patients with a higher compared with a lower ferritin level had an elevated risk of CCVD and infectious disease. Moreover, the risk of death was significantly higher among patients with high-amplitude ferritin fluctuations compared with those with a low ferritin level. The risks of CCVD, infection, and hospitalization were significantly higher among patients who were treated with high weekly doses of intravenous iron compared with no intravenous iron. Thus, there is a high risk of death and/or adverse events in patients with hemoglobin levels outside the target range, in those with high-amplitude hemoglobin fluctuations, in those with consistently high serum ferritin levels, and in those with high-amplitude ferritin fluctuations.