Physical health-related quality of life at higher achieved hemoglobin levels among chronic kidney disease patients: a systematic review and meta-analysis

UK kidney association clinical practice guideline: update of anaemia of chronic kidney disease

Anaemia is common in chronic kidney disease (CKD) encompassing non-dialysis dependent CKD (NDD-CKD) and dialysis dependent CKD (DD-CKD); people on peritoneal dialysis (PD) and haemodialysis (HD); and kidney transplant recipients (KTR). Iron deficiency and erythropoietin deficiency are the most common causes of anaemia in people with CKD, especially those requiring kidney replacement therapy (KRT). The Renal National Service Framework and National Institute for Health and Clinical Excellence in the UK, and Kidney Disease Improving Global Outcomes (KDIGO), all advocate treatment of anaemia in people with CKD. Blood transfusions are infrequently required, and newer therapies such as Hypoxia-Inducible Factor (HIF-PHI) stabilisers are now in current use. This guideline provides evidence based graded practice guidance on the use of iron; comments on iron deficiency without anaemia in people with CKD; provide further information on anaemia management in people with a transplant and provide guidance in the use of the new HIF-PHI drugs. It also provides audit and research recommendations.

Erythrocyte indices and response to hypoxia-inducible factor prolyl hydroxylase inhibitors in chronic kidney disease patients with renal anemia: a retrospective study

BACKGROUND

Although erythropoiesis-stimulating agents (ESAs) have been the standard treatment for renal anemia, ESA hyporesponsiveness remains a concern. Hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) are a new class of agents indicated for renal anemia. Several lines of evidence indicate that HIF-PHIs affect erythrocyte indices; nonetheless, their clinical significance remains unclear.

METHODS

We retrospectively analyzed data from 233 non-dialysis-dependent chronic kidney disease patients who initiated either ESA (darbepoetin) or HIF-PHI for the treatment of anemia. We analyzed the changes in hemoglobin levels three months after the initiation of anti-anemic treatments, examining their association with changes in erythrocyte indices.

RESULTS

Both ESA and HIF-PHIs significantly increased hemoglobin levels after three months of treatment. In the HIF-PHI group, the increase in hemoglobin levels was positively correlated with the increase in mean corpuscular volume (MCV) levels, a finding that was not observed in the ESA group. In a subgroup analysis based on the mean reference range value for MCV (90.9 fL), a significant difference in the proportion of patients with improved anemia was observed between ESA and HIF-PHIs in patients with lower MCV values. Logistic regression and interaction analyses confirmed that there was a significant interaction between baseline MCV values and the effectiveness of anti-anemic drugs, independently of other covariates.

CONCLUSIONS

An increase in hemoglobin levels is associated with an increase in MCV in patients treated with HIF-PHIs. The anti-anemic effects of ESA and HIF-PHIs may be influenced by baseline MCV values. However, long-term consequences need further evaluation.

Hemoincompatibility in Hemodialysis-Related Therapies and Their Health Economic Perspectives

Hemobiologic reactions associated with the hemoincompatibility of extracorporeal circuit material are an undesirable and inevitable consequence of all blood-contacting medical devices, typically considered only from a clinical perspective. In hemodialysis (HD), the blood of patients undergoes repetitive (at least thrice weekly for 4 h and lifelong) exposure to different polymeric materials that activate plasmatic pathways and blood cells. There is a general agreement that hemoincompatibility reactions, although unavoidable during extracorporeal therapies, are unphysiological contributors to non-hemodynamic dialysis-induced systemic stress and need to be curtailed. Strategies to lessen the periodic and direct effects of blood interacting with artificial surfaces to stimulate numerous biological pathways have focused mainly on the development of 'more passive' materials to decrease intradialytic morbidity. The indirect implications of this phenomenon, such as its impact on the overall delivery of care, have not been considered in detail. In this article, we explore, for the first time, the potential clinical and economic consequences of hemoincompatibility from a value-based healthcare (VBHC) perspective. As the fundamental tenet of VBHC is achieving the best clinical outcomes at the lowest cost, we examine the equation from the individual perspectives of the three key stakeholders of the dialysis care delivery processes: the patient, the provider, and the payer. For the patient, sub-optimal therapy caused by hemoincompatibility results in poor quality of life and various dialysis-associated conditions involving cost-impacting adjustments to lifestyles. For the provider, the decrease in income is attributed to factors such as an increase in workload and use of resources, dissatisfaction of the patient from the services provided, loss of reimbursement and direct revenue, or an increase in doctor-nurse turnover due to the complexity of managing care (nephrology encounters a chronic workforce shortage). The payer and healthcare system incur additional costs, e.g., increased hospitalization rates, including intensive care unit admissions, and increased medications and diagnostics to counteract adverse events and complications. Thus, hemoincompatibility reactions may be relevant from a socioeconomic perspective and may need to be addressed beyond just its clinical relevance to streamline the delivery of HD in terms of payability, future sustainability, and societal repercussions. Strategies to mitigate the economic impact and address the cost-effectiveness of the hemoincompatibility of extracorporeal kidney replacement therapy are proposed to conclude this comprehensive approach.

Post-transplant renal anemia: a call to action from a national study in routine clinical practice

Background

Post-transplant anemia is a prevalent yet often overlooked condition that poses significant risks. Current guidelines consider the same treatment recommendations and goals for these patients as for chronic kidney disease patients not on dialysis. Previous reports demonstrated a lack of awareness and suboptimal management, indicating a pressing need for improvement. We therefore wanted to update the information on post-transplant anemia. We aimed to describe the present state of anemia management, goals and adherence to guidelines within a representative sample of the kidney transplant (KTx) population.

Methods

We designed a retrospective nationwide multicenter study including outpatients from eight KTx hospitals. Nephrologists gathered data from electronic medical records encompassing demographics, comorbidities, KTx characteristics and immunosuppressive therapy, and information pertaining to anemia management (laboratory values, previously prescribed treatments and subsequent adjustments). The European statement on the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines was the reference for definitions, drug prescriptions and targets. Anemia occurring within the initial 6 months post-transplantation was classified as early onset.

Results

We included 297 patients with post-transplant anemia aged 62.8 years (standard deviation 13.6), 60% of whom were male. They had received a graft from cardiac death or brain death donors (61.6% and 31.1%, respectively) a median of 2.5 years (0.5-8.7) before. Among them 77% (n = 228) were classified as having late post-transplant anemia, characterized by a higher prevalence of microcytic and iron deficiency anemia. A total of 158 patients were on erythropoietic-stimulating agents (ESAs) treatment, yet surprisingly 110 of them lacked iron supplementation. Notably, 44 patients had an indication for iron supplementation and among them, 30 exhibited absolute iron deficiency. Out of the 158 patients receiving ESAs, only 39 surpassed the limit for the ESA resistance index, indicating poor response. This resistance was more frequent among patients with early post-transplant anemia (26.1% vs 9.2%). We have identified iron profile, early post-transplant anemia and estimated glomerular filtration rate as factors associated with the highest risk of resistance.

Conclusion

We found that hemoglobin targets are individualized upwards in post-transplant anemia. In this setting, iron therapy continues to be underutilized, especially intravenous, and iron deficiency and prior events (blood transfusion or hospital admission) explain most of the hyporesponsiveness to ESA. This highlights missed opportunities for precise prescription targeting and adherence to established guidelines, suggesting a need for improved management strategies in post-transplant anemia patients.

Iron biology

Iron is a fundamental element for biological life, from bacteria to humans. Iron is essential for cell function and survival, energy production and metabolism, whereas increased levels cause oxidative stress. It is also a constituent of haemoglobin and thus it is necessary for oxygen transportation through the body. Given these multiple functions, the regulation of iron metabolism is complex and tight coupled with oxygen homeostasis at tissue and cellular levels, thanks to the interaction with the hypoxia inducible factor system. In patients with chronic kidney disease (CKD), iron deficiency significantly contributes to anaemia development. This frequently overlaps with chronic inflammation, causing iron- restricted erythropoiesis. To add further complexity, metabolic hyperferritinemia may, on one hand, increase the risk for CKD and, on the other, overlaps with functional iron deficiency. Excessive intracellular iron in certain cell types during CKD can also mediate cellular death (called ferroptosis), and contribute to the pathogenesis of kidney damage, atherosclerosis and vascular calcifications. This review is aimed at broadening the perspective of iron metabolism in the setting of CKD not just as a contributor to anaemia in CKD patients, but also as an important player with an impact on cell metabolism, renal fibrosis and the cardiovascular system.

Hemoglobin level is negatively associated with sarcopenia and its components in Chinese aged 60 and above

Introduction

Sarcopenia and low hemoglobin level are common in older adults. Few studies have evaluated the association between hemoglobin level and sarcopenia and with inconsistent findings. The multifaceted effects of sarcopenia on the human body and the high prevalence of anemia in the Chinese population make it necessary to explore the association between the two.

Methods

Using the China Health and Retirement Longitudinal Study (CHARLS), we explored the association between hemoglobin with sarcopenia and its components in the Chinese population aged 60 and above. Multivariate logistic and Cox proportional hazards models were constructed to examine the association of hemoglobin level with sarcopenia and sarcopenia components in individuals aged 60 years or above. The subgroup analysis covered residence, body mass index level, drinking status, and smoking status were conducted. The possible difference of associations between sexes was also explored.

Results

With a total of 3,055 people, the hemoglobin concentration in people without sarcopenia, possible sarcopenia, and sarcopenia are 14.34 ± 2.22, 14.64 ± 2.27, and 13.58 ± 2.02 g/dl, respectively. Cross-sectional analysis showed strong evidence that hemoglobin was negatively associated with sarcopenia [Odds Ratio (OR) = 0.95, 95% Confidence Interval (CI): 0.90-0.99] and low height-adjusted appendicular skeletal muscle mass (OR = 0.91, 95% CI: 0.86-0.97). On average, a per 1 g/dl higher hemoglobin level was associated with 5% lower odds of sarcopenia (OR = 0.95, 95% CI: 0.90-0.98). The cohort study of 1,022 people demonstrated a statistically significant negative association of hemoglobin level with low physical performance [Hazard Ratio (HR) = 0.92, 95% CI: 0.85-0.99], merely with sarcopenia (HR = 0.92, 95% CI: 0.84-1.00) and skeletal muscle mass (HR = 0.95, 95% CI: 0.80-1.00). Sex-specific analysis suggested hemoglobin's association with sarcopenia, muscle mass, and physical performance in all sexes, with weaker magnitudes in females. Hemoglobin in urban residents and people with high body mass index (BMI) has a larger magnitude of the negative association with sarcopenia.

Discussion

Hemoglobin level associates with sarcopenia, muscle mass, and physical performance in the Chinese population aged 60 and above, with sex-specific, residence-specific, and BMI-specific effects.

[Anemia and quality of life of chronic kidney disease patients on renal replacement therapy by programmed hemodialysis]

AIM

To study relationship between anemia and health-related quality of life (HRQOL) of chronic kidney disease stage 5 patients (CKD) undergoing renal replacement therapy by programmed hemodialysis.

MATERIALS AND METHODS

The study was conducted on the basis of dialysis centers/departments in Moscow. The Russian-language version of the KDQOL-SF^TM questionnaire, validated in Russia, was used to assess the HRQOL of patients on hemodialysis. A total of 723 patients were interviewed. Hemoglobin (Hb) levels were assessed in 442 patients based on outpatient records. To identify the relationship between Hb level and HRQOL scales, a correlation analysis was performed, as well as a HRQOL analysis in the three groups differing in hemoglobin levels (<100; 100-120 and >120 g/l). Statistical data processing was carried by SPSS.22 and using parametric and nonparametric statistical methods.

RESULTS

Correlation relationship was revealed between Hb and HRQOL of patients on hemodialysis on the scales "symptoms/problems", "pain", "vital activity, energy" and "total physical component of health". According to the scales "symptoms/problems" and "vital activity, energy", higher rates were noted among patients with Hb higher than the target level, which confirms the recommendations concerning the possibility of achieving higher Hb among individual patients who have not serious concomitant diseases and cardiovascular complications in order to improve their quality of life.

CONCLUSION

HRQOL assessment is important tool for planning and evaluating the effectiveness of anemia drug therapy among patients with CKD on hemodialysis.

Hemoglobin modulation affects physiology and patient reported outcomes in anemic and non-anemic subjects: An umbrella review

Background: An abnormal hemoglobin concentration has a substantial effect on a person's quality of life and physiology. Lack of tools that effectively evaluate hemoglobin-related outcomes leads to uncertainty regarding optimal hemoglobin levels, transfusion thresholds and treatment targets. We therefore aim to summarize reviews that assess the effects of hemoglobin modulation on the human physiology at various baseline hemoglobin levels, and identify gaps in existing evidence. Methods: We conducted an umbrella review of systematic reviews. PubMed, MEDLINE (OVID), Embase, Web of Science, Cochrane Library and Emcare were searched from inception to the 15th of April 2022 for studies that reported on physiological and patient reported outcomes following a hemoglobin change. Results: Thirty-three reviews were included of which 7 were scored as of high quality and 24 of critically low quality using the AMSTAR-2 tool. The reported data generally show that an increase in hemoglobin leads to improvement of patient reported and physical outcomes in anaemic and non-anaemic subjects. At lower hemoglobin levels, the effect of a hemoglobin modulation on quality of life measures appears more pronounced. Conclusion: This overview has revealed many knowledge gaps due to a lack of high-quality evidence. For chronic kidney disease patients, a clinically relevant benefit of increasing the hemoglobin levels up until 12 g/dL was found. However, a personalized approach remains necessary due to the many patient-specific factors that affect outcomes. We strongly encourage future trials to incorporate physiological outcomes as objective parameters together with subjective, but still very important, patient reported outcome measures.

Predicting mortality risk in dialysis: Assessment of risk factors using traditional and advanced modeling techniques within the Monitoring Dialysis Outcomes initiative

INTRODUCTION

Several factors affect the survival of End Stage Kidney Disease (ESKD) patients on dialysis. Machine learning (ML) models may help tackle multivariable and complex, often non-linear predictors of adverse clinical events in ESKD patients. In this study, we used advanced ML method as well as a traditional statistical method to develop and compare the risk factors for mortality prediction model in hemodialysis (HD) patients.

MATERIALS AND METHODS

We included data HD patients who had data across a baseline period of at least 1 year and 1 day in the internationally representative Monitoring Dialysis Outcomes (MONDO) Initiative dataset. Twenty-three input parameters considered in the model were chosen in an a priori manner. The prediction model used 1 year baseline data to predict death in the following 3 years. The dataset was randomly split into 80% training data and 20% testing data for model development. Two different modeling techniques were used to build the mortality prediction model.

FINDINGS

A total of 95,142 patients were included in the analysis sample. The area under the receiver operating curve (AUROC) of the model on the test data with XGBoost ML model was 0.84 on the training data and 0.80 on the test data. AUROC of the logistic regression model was 0.73 on training data and 0.75 on test data. Four out of the top five predictors were common to both modeling strategies.

DISCUSSION

In the internationally representative MONDO data for HD patients, we describe the development of a ML model and a traditional statistical model that was suitable for classification of a prevalent HD patient's 3-year risk of death. While both models had a reasonably high AUROC, the ML model was able to identify levels of hematocrit (HCT) as an important risk factor in mortality. If implemented in clinical practice, such proof-of-concept models could be used to provide pre-emptive care for HD patients.

The Impact of Anaemia on Outcomes, Admissions, and Costs in Patients with Chronic Kidney Disease in Two Public Nephrology Practices in Queensland: A CKD.QLD Registry Study

Aim

Anaemia among patients with chronic kidney disease (CKD) leads to poor overall outcomes. This study explores anaemia and its impact on nondialysis CKD (NDD-CKD) patients.

Methods

2,303 adults with CKD from two CKD.QLD Registry sites were characterised at consent and followed until start of kidney replacement therapy (KRT), death, or censor date. Mean follow-up was 3.9 (SD 2.1) years. Analysis explored the impact of anaemia on death, KRT start, cardiovascular events (CVE), admissions, and costs in these NDD-CKD patients.

Results

At consent, 45.6% patients were anaemic. Males were more often anaemic (53.6%) than females, and anaemia was significantly more common over the age of 65 years. The prevalence of anaemia was highest among CKD patients with diabetic nephropathy (27.4%) and renovascular disease (29.2%) and lowest in patients with genetic renal disease (3.3%). Patients with admissions for gastrointestinal bleeding had more severe anaemia, but accounted for only the minority of cases overall. Administration of ESAs, iron infusions, and blood transfusions were all correlated with more severe degrees of anaemia. The number of hospital admissions, length of stay, and hospital costs were all strikingly higher with more severe degrees of anaemia. Adjusted hazard ratios (CI 95%) of patients with moderate and severe anaemia vs. no anaemia for subsequent CVE, KRT, and death without KRT were 1.7 (1.4-2.0), 2.0 (1.4-2.9), and 1.8 (1.5-2.3), respectively.

Conclusion

Anaemia is associated with higher rates of CVE, progression to KRT and death in NDD- CKD patients, and with greater hospital utilisation and costs. Preventing and treating anaemia should improve clinical and economic outcomes.

Evolving Strategies in the Treatment of Anaemia in Chronic Kidney Disease: The HIF-Prolyl Hydroxylase Inhibitors

Chronic kidney disease (CKD) affects approximately 10% of the worldwide population; anaemia is a frequent complication. Inadequate erythropoietin production and absolute or functional iron deficiency are the major causes. Accordingly, the current treatment is based on iron and erythropoiesis stimulating agents (ESAs). Available therapy has dramatically improved the management of anaemia and the quality of life. However, safety concerns were raised over ESA use, especially when aiming to reach near-to-normal haemoglobin levels with high doses. Moreover, many patients show hypo-responsiveness to ESA. Hypoxia-inducible factor (HIF) prolyl hydroxylase domain (PHD) inhibitors (HIF-PHIs) were developed for the oral treatment of anaemia in CKD to overcome these concerns. They simulate the body's exposure to moderate hypoxia, stimulating the production of endogenous erythropoietin. Some molecules are already approved for clinical use in some countries. Data from clinical trials showed non-inferiority in anaemia correction compared to ESA or superiority for placebo. Hypoxia-inducible factor-prolyl hydroxylase domain inhibitors may also have additional advantages in inflamed patients, improving iron utilisation and mobilisation and decreasing LDL-cholesterol. Overall, non-inferiority was also shown in major cardiovascular events, except for one molecule in the non-dialysis population. This was an unexpected finding, considering the lower erythropoietin levels reached using these drugs due to their peculiar mechanism of action. More data and longer follow-ups are necessary to better clarifying safety issues and further investigate the variety of pathways activated by HIF, which could have either positive or negative effects and could differentiate HIF-PHIs from ESAs.

Relación entre bienestar psicológico y la percepción de calidad de vida en pacientes en hemodiálisis

Introducción: La hemodiálisis es la alternativa terapéutica más empleada en los pacientes con enfermedad renal crónica; sin embargo, no se han establecido de forma multidimensional las condiciones de bienestar psicológico y la calidad de vida de estos pacientes.Objetivo: Analizar el perfil de bienestar psicológico y percepción de calidad de vida de pacientes en hemodiálisis, así como diferenciar e identificar la relación entre estas variables.Material y método: Estudio observacional descriptivo transversal realizado a 173 pacientes en hemodiálisis. Se emplearon los cuestionarios PGWBI para evaluar el bienestar psicológico y el WHOQOL-BREF para la calidad de vida.Resultados: Pacientes con ERC en tratamiento con HD con un promedio de 57,59±13,31 años, predominantemente de género masculino (n=110; 63,58%). Se encontraron altos índices de bienestar psicológico (78,61%) y percepciones moderadas de calidad de vida (54,91%), acompañadas de sintomatología depresiva (97,11%) y ansiosa (97,11%). La edad, nivel educativo, condición laboral, ingresos económicos, tener Diabetes Mellitus y concentraciones sanguíneas inadecuadas de hemoglobina, potasio y fósforo, mostraron diferencias en los dominios y categorías (p<0,01). El análisis correlacional encontró una estrecha relación lineal entre las dos variables estudiadas (r=0,81; p=0,0001).Conclusiones: Los participantes del estudio mostraron altas percepciones de bienestar psicológico y moderadas apreciaciones de calidad de vida a expensas de elevadas valoraciones de positividad, autocontrol, vitalidad y percepciones de salud física, psicológica y relaciones sociales. El bienestar psicológico desde sus diferentes categorías influencia directamente la percepción de calidad de vida de los pacientes en hemodiálisis.

Iron Supplementation Improves Skeletal Muscle Contractile Properties in Mice with CKD

Background

Patients with chronic kidney disease (CKD) frequently have compromised physical performance, which increases their mortality; however, their skeletal muscle dysfunction has not been characterized at the single-fiber and molecular levels. Notably, interventions to mitigate CKD myopathy are scarce.

Methods

The effect of CKD in the absence and presence of iron supplementation on the contractile function of individual skeletal muscle fibers from the soleus and extensor digitorum longus muscles was evaluated in 16-week-old mice. CKD was induced by the adenine diet, and iron supplementation was by weekly iron dextran injections.

Results

Maximally activated and fatigued fiber force production was decreased 24%-52% in untreated CKD, independent of size, by reducing strongly bound myosin/actin cross-bridges and/or decreasing myofilament stiffness in myosin heavy chain (MHC) I, IIA, and IIB fibers. Additionally, myosin/actin interactions in untreated CKD were slower for MHC I and IIA fibers and unchanged or faster in MHC IIB fibers. Iron supplementation improved anemia and did not change overall muscle mass in CKD mice. Iron supplementation ameliorated CKD-induced myopathy by increasing strongly bound cross-bridges, leading to improved specific tension, and/or returning the rate of myosin/actin interactions toward or equivalent to control values in MHC IIA and IIB fibers.

Conclusions

Skeletal muscle force production was significantly reduced in untreated CKD, independent of fiber size, indicating that compromised physical function in patients is not solely due to muscle mass loss. Iron supplementation improved multiple aspects of CKD-induced myopathy, suggesting that timely correction of iron imbalance may aid in ameliorating contractile deficits in CKD patients.

Anemia Management in the Cancer Patient With CKD and End-Stage Kidney Disease

Anemia is a common medical problem among patients with cancer and chronic kidney disease (CKD). Although anemia in patients with CKD is often treated with iron and erythropoietin-stimulating agents, there are controversies with regard to the use of erythropoietin-stimulating agents in cancer patients. In this article, we review the treatment of anemia in patients with cancer and CKD, in addition to summarizing the current guidelines in treatment of anemia in these patients.

Health-related quality of life in patients with chronic kidney disease

Introduction: In the last three decades, health systems have continued to pay increasing attention to the quality of life (QOL) due to definitional changes in the concept of health and disease. The health-related quality of life (HRQOL) in patients with chronic kidney disease (CKD) is significantly affected, regardless of the stage of CKD. Areas covered: We attempt to thoroughly explore how CKD affects HRQOL domains with a quick primer on HRQOL assessment instruments in patients with CKD. Also, we pointed out the factors affecting HRQOL in patients with CKD as well as the clinical application of HRQOL in CKD management. Expert opinion: The general population enjoys higher HRQOL than patients with CKD in all domains. Similarly, pre-dialysis and kidney-transplant patients have better HRQOL than dialysis population. There are many factors which negatively impact HRQOL in CKD which include for example depression, anxiety, and cognitive impairment for the social domain, inactivity, and frailty for the physical domain as well as lack of social support and extroversion in the social domain. Additionally, social disparities and CKD-related factors would influence HRQOL. Of note, there is no global standard HRQOL assessment tool. Finally, HRQOL should be included in future CKD management guidelines.