Iron Deficiency Anemia in Chronic Kidney Disease

Physician and Patient Preferences for Treatment of Anemia Associated with Chronic Kidney Disease in Japan: A Survey Including Best-Worst Scaling

Background

Several treatment options are available for anemia associated with chronic kidney disease (CKD); however, there remains a lack of awareness of physician and patient preferences regarding these treatments. We aimed to explore physicians' and patients' perceptions and preferences regarding the management of anemia of CKD in Japan.

Methods

A web-based survey, including best-worst scaling (BWS), was conducted with physicians who had treated ≥1 patient with anemia of CKD in the preceding year, and with patients with CKD who self-reported a clinical diagnosis of anemia of CKD or low hemoglobin levels. A three-step approach was used comprising cognitive interviews, a pilot survey, and a main survey. The BWS survey results were analyzed using multinomial logit and hierarchical Bayesian models.

Results

The survey was completed by 906 participants: 103 patients (average age 60.6 years; 77.7% male) and 803 physicians (166 nephrologists, 214 cardiologists, 137 diabetologists, and 286 general internists). Almost all (96.0%) physicians surveyed considered anemia of CKD to be an important condition to treat. Hypoxia-inducible factor prolyl hydroxylase (HIF-PH) inhibitors had the highest treatment satisfaction among physicians, whereas patients had the highest satisfaction with both erythropoietin-stimulating agent therapy and HIF-PH inhibitors. Approximately one-third (35.9%) of patients surveyed indicated that they were receiving treatment. When comparing the relative importance of attributes and levels, physicians favored efficacy (particularly improvement in hemoglobin levels), whereas patients favored safety (particularly a lower rate of severe adverse events).

Conclusion

Although a majority of physicians consider treatment of CKD-related anemia important, differences in the perceptions and usage of medications exist between medical specialties. Preferences for the management of anemia of CKD vary between physicians and patients; therefore, patient involvement in treatment decisions may help optimize outcomes.

Habitual Iron Supplementation Associated with Elevated Risk of Chronic Kidney Disease in Individuals with Antihypertensive Medication

The aim of this study was to examine the effects of habitual iron supplementation on the risk of CKD in individuals with different hypertensive statuses and antihypertension treatment statuses. We included a total of 427,939 participants in the UK Biobank study, who were free of CKD and with complete data on blood pressure at baseline. Cox proportional hazards regression models were used to examine the adjusted hazard ratios of habitual iron supplementation for CKD risk. After multivariable adjustment, habitual iron supplementation was found to be associated with a significantly higher risk of incident CKD in hypertensive participants (HR 1.12, 95% CI 1.02 to 1.22), particularly in those using antihypertensive medication (HR 1.21, 95% CI 1.08 to 1.35). In contrast, there was no significant association either in normotensive participants (HR 1.06, 95% CI 0.94 to 1.20) or in hypertensive participants without antihypertensive medication (HR 1.02, 95% CI 0.90 to 1.17). Consistently, significant multiplicative and additive interactions were observed between habitual iron supplementation and antihypertensive medication on the risk of incident CKD (p all interaction < 0.05). In conclusion, habitual iron supplementation was related to a higher risk of incident CKD among hypertensive patients, the association might be driven by the use of antihypertensive medication.

Key performance indicators for monitoring of anemia management and iron status in children attending a pediatric dialysis unit: the experience of Ain Shams University

BACKGROUND

Anemia in children on maintenance hemodialysis (HD) leads to poor quality of life. Our study aimed to assess and monitor anemia and iron status management in children on maintenance HD over 18 months using key performance indicators.

METHODS

Key performance indicators, formulated as the percentage of patients achieving the KDIGO (2012) guideline-recommended targets for hemoglobin (Hb) (11-12 g/dl), transferrin saturation (TSAT) (20-40%) and serum ferritin (200-500 ng/ml), were reported quarterly over the 18-month-period of this study.

RESULTS

This study was carried out over an 18 month-period, from April 1st, 2020, till October 31st, 2021. A total of 78 patients (45 males and 33 females) were included; mean age 12.16 ± 3.3 years and HD duration range 3.0-140.88 months, median 16.51 months. The three most common primary causes of CKD were Congenital Anomalies of the Kidney and Urinary Tract (CAKUT) (29.5%), unknown cause (24.4%), and chronic glomerular diseases (20.5%). The quarterly reported percentages of patients achieving the recommended targets for Hb, TSAT, and serum ferritin ranges were 18.2-35.7%, 38.8-57.1%, and 11.9-26.6%, respectively.

CONCLUSION

Although the mean Hb trend was nearing the KDIGO (2012) target, the key performance indicators showed that only a small percentage of our HD patients were achieving the targets for Hb, TSAT, & serum ferritin, thus alerting us to the need to revise our protocol for the management of anemia and iron status.

Renal anemia: from relative insufficiency of EPO to imbalance of erythropoiesis and eryptosis

Chronic kidney disease has emerged as a major health issue both in China and worldwide. Renal anemia frequently occurs in patients with chronic kidney disease, and its severity and incidence rate increase as the disease progresses. Over the last 30 years, the administration of exogenous EPO and EPO stimulants has been employed to alleviate renal anemia, suggesting that a relative deficiency in EPO may be a primary cause. However, this approach has overshadowed other contributing factors, particularly eryptosis, which results from the reduced lifespan of red blood cells. Numerous studies reveal that there are nephrogenic and extrarenal EPO secretion indicating that an absolute deficiency of EPO is not always present in patients. Therefore, this paper speculates that renal anemia may arise when EPO-driven erythropoiesis fails to adequately compensate for aggravating eryptosis. Other factors including iron metabolism disorder, uremic toxin accumulation, inflammatory state, oxidative stress, and secondary hyperparathyroidism affect EPO reactivity bone marrow hematopoiesis and eryptosis, leading to an imbalance between red blood cell production and destruction, and cause anemia ultimately. More further studies on the pathogenesis and treatment of renal anemia would be expected to provide evidence to support our opinion.

Preventing potential pitfalls of a liberalized potassium diet in the hemodialysis population

Emerging research suggests that a more liberalized diet, specifically a more plant-based diet resulting in liberalization of potassium intake, for people receiving hemodialysis is necessary and the benefits outweigh previously thought risks. If the prescribed hemodialysis diet is to be liberalized, the need to illuminate and prevent potential pitfalls of a liberalized potassium diet is warranted. This paper explores such topics as partial to full adherence to a liberalized diet and its consequences if any, the advantages of a high-fiber intake, the theoretical risk of anemia when consuming a more plant-dominant diet, the potential benefits against renal acid load and effect on metabolic acidosis with increased fruit and vegetable intake, the putative change in serum potassium levels, carbohydrate quality, and the healthfulness of meat substitutes. The benefits of a more plant-based diet for the hemodialysis population are multifold; however, the possible pitfalls of this type of diet must be reviewed and addressed upon meal planning in order to be avoided.

Regulated vascular smooth muscle cell death in vascular diseases

Regulated cell death (RCD) is a complex process that involves several cell types and plays a crucial role in vascular diseases. Vascular smooth muscle cells (VSMCs) are the predominant elements of the medial layer of blood vessels, and their regulated death contributes to the pathogenesis of vascular diseases. The types of regulated VSMC death include apoptosis, necroptosis, pyroptosis, ferroptosis, parthanatos, and autophagy-dependent cell death (ADCD). In this review, we summarize the current evidence of regulated VSMC death pathways in major vascular diseases, such as atherosclerosis, vascular calcification, aortic aneurysm and dissection, hypertension, pulmonary arterial hypertension, neointimal hyperplasia, and inherited vascular diseases. All forms of RCD constitute a single, coordinated cell death system in which one pathway can compensate for another during disease progression. Pharmacologically targeting RCD pathways has potential for slowing and reversing disease progression, but challenges remain. A better understanding of the role of regulated VSMC death in vascular diseases and the underlying mechanisms may lead to novel pharmacological developments and help clinicians address the residual cardiovascular risk in patients with cardiovascular diseases.

Management of chronic kidney disease: The current novel and forgotten therapies

Chronic kidney disease (CKD) is a progressive and incurable condition that imposes a significant burden on an aging society. Although the exact prevalence of this disease is unknown, it is estimated to affect at least 800 million people worldwide. Patients with diabetes or hypertension are at a higher risk of developing chronic kidney damage. As the kidneys play a crucial role in vital physiological processes, damage to these organs can disrupt the balance of water and electrolytes, regulation of blood pressure, elimination of toxins, and metabolism of vitamin D. Early diagnosis is paramount to prevent potential complications. Treatment options such as dietary modifications and medications can help slow disease progression. In our narrative review, we have summarized the available therapeutic options to slow the progression of chronic kidney disease. Many new drug treatments have recently become available, offering a beacon of hope and optimism in CKD management. Nonetheless, disease prevention remains the most critical step in disease management. Given the significant impact of CKD on public health, there is a pressing need for further research. With the development of new technologies and advancements in medical knowledge, we hope to find more effective diagnostic tools and treatments for CKD patients.

Cardiovascular outcomes and molecular targets for the cardiac effects of Sodium-Glucose Cotransporter 2 Inhibitors: A systematic review

Sodium-glucose cotransporter 2 inhibitors (SGLT2i), a new class of glucose-lowering drugs traditionally used to control blood glucose levels in patients with type 2 diabetes mellitus, have been proven to reduce major adverse cardiovascular events, including cardiovascular death, in patients with heart failure irrespective of ejection fraction and independently of the hypoglycemic effect. Because of their favorable effects on the kidney and cardiovascular outcomes, their use has been expanded in all patients with any combination of diabetes mellitus type 2, chronic kidney disease and heart failure. Although mechanisms explaining the effects of these drugs on the cardiovascular system are not well understood, their effectiveness in all these conditions suggests that they act at the intersection of the metabolic, renal and cardiac axes, thus disrupting maladaptive vicious cycles while contrasting direct organ damage. In this systematic review we provide a state of the art of the randomized controlled trials investigating the effect of SGLT2i on cardiovascular outcomes in patients with chronic kidney disease and/or heart failure irrespective of ejection fraction and diabetes. We also discuss the molecular targets and signaling pathways potentially explaining the cardiac effects of these pharmacological agents, from a clinical and experimental perspective.

Anemia of Chronic Kidney Disease-A Narrative Review of Its Pathophysiology, Diagnosis, and Management

Anemia is one of the most common chronic kidney disease (CKD) complications. It negatively affects patients' quality of life and clinical outcomes. The pathophysiology of anemia in CKD involves the interplay of various factors such as erythropoietin (EPO) deficiency, iron dysregulation, chronic inflammation, bone marrow dysfunction, and nutritional deficiencies. Despite recent advances in understanding this condition, anemia still remains a serious clinical challenge in population of patients with CKD. Several guidelines have been published with the aim to systematize the diagnostic approach and treatment of anemia; however, due to emerging data, many recommendations vary between publications. Recent studies indicate a potential of novel biomarkers to evaluate anemia and related conditions such as iron deficiency, which is often present in CKD patients. Our article aims to summarize the pathophysiology of anemia in CKD, as well as the diagnosis and management of this condition, including novel therapeutic approaches such as hypoxia-inducible factor-prolyl hydroxylase inhibitors (HIF-PHI). Understanding these complex subjects is crucial for a targeted approach to diagnose and treat patients with anemia in CKD effectively.

Alterations in regulators of the renal-bone axis, inflammation and iron status in older people with early renal impairment and the effect of vitamin D supplementation

CONTEXT

Chronic kidney disease (CKD) leads to alterations in fibroblast growth factor 23 (FGF23) and the renal-bone axis. This may be partly driven by altered inflammation and iron status. Vitamin D supplementation may reduce inflammation.

OBJECTIVE AND METHODS

Older adults with early CKD (estimated glomerular filtration rate (eGFR) 30-60 ml/min/1.73 m2; CKDG3a/b; n = 35) or normal renal function (eGFR >90 ml/min/1.73 m2; CKDG1; n = 35) received 12,000, 24,000 or 48,000 IU D3/month for 1 year. Markers of the renal-bone axis, inflammation and iron status were investigated pre- and post-supplementation. Predictors of c-terminal and intact FGF23 (cFGF23; iFGF23) were identified by univariate and multivariate regression.

RESULTS

Pre-supplementation, comparing CKDG3a/b to CKDG1, plasma cFGF23, iFGF23, PTH, sclerostin and TNFα were significantly higher and Klotho, 1,25-dihydroxyvitamin D and iron were lower. Post-supplementation, only cFGF23, 25(OH)D and IL6 differed between groups. The response to supplementation differed between eGFR groups. Only in the CKDG1 group, phosphate decreased, cFGF23, iFGF23 and procollagen type I N-propeptide increased. In the CKDG3a/b group, TNFα significantly decreased, and iron increased. Plasma 25(OH)D and IL10 increased, and carboxy-terminal collagen crosslinks decreased in both groups. In univariate models cFGF23 and iFGF23 were predicted by eGFR and regulators of calcium and phosphate metabolism at both time points; IL6 predicted cFGF23 (post-supplementation) and iFGF23 (pre-supplementation) in univariate models. Hepcidin predicted post-supplementation cFGF23 in multivariate models with eGFR.

CONCLUSION

Alterations in regulators of the renal-bone axis, inflammation and iron status were found in early CKD. The response to vitamin D3 supplementation differed between eGFR groups. Plasma IL6 predicted both cFGF23 and iFGF23 and hepcidin predicted cFGF23.

Iron Deficiency in Newly Referred Patients With Chronic Renal Failure

Addressing iron deficiency is the key to managing anemia in patients with chronic kidney disease (CKD). Erythropoiesis-stimulating agents (ESAs) and hypoxia-inducible factor prolyl-hydroxylase inhibitors (HIF-PHIs) are being prescribed to an increasing number of patients with CKD by primary physicians following the emergence of newer agents for the management of renal anemia. Among the 361 (average age: 76.8±12.1 years; 54.0% males) patients with stages 4 and 5 CKD newly referred to the nephrology department of our hospital between 2018 and 2023 who had evaluable transferrin saturation (TSAT) and ferritin levels, 169 patients (47%) had iron deficiency (ferritin <100 ng/mL or ferritin 100-300 ng/mL with TSAT <20%). The estimated glomerular filtration rate (eGFR), hemoglobin level, TSAT, and median ferritin level were 17.0±7.0 mL/min/1.73 m², 10.8±2.1 g/dL, 27.5±13.1%, and 130 ng/mL, respectively. ESAs, HIF-PHIs, and iron supplements were prescribed to 35 (9.7%), 17 (4.7%), and 35 (9.4%) patients, respectively. No significant differences were observed between the iron indices of the ESA group; however, the serum ferritin levels in the HIF-PHIs group were significantly lower than in those in the no-medication group (P=0.02). Multivariable logistic regression analysis revealed that age, female sex, eGFR, medications for renal anemia, and a history of ischemic heart disease were associated with iron deficiency (P<0.05). Although patients with renal failure tend to exhibit anemia, attention should be paid to iron deficiency anemia in addition to renal anemia, especially in patients with renal failure and a history of ischemic heart disease.

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.

Interaction between anemia and hyperuricemia in the risk of all-cause mortality in patients with chronic kidney disease

Aim

Both hyperuricemia and anemia are not only the manifestation of chronic kidney disease (CKD) but also related to its occurrence and development. A recent study has found that there was a synergetic effect between hyperuricemia and anemia on new-onset CKD. Herein we aimed to explore the roles of hyperuricemia and anemia in the all-cause mortality in patients with CKD.

Methods

Data of adult patients with CKD were extracted from the National Health and Nutrition Examination Surveys (NHANES) database in 2009-2018 in this retrospective cohort study. Weighted univariate and multivariate COX regression analyses were used to investigate the associations of hyperuricemia and anemia with all-cause mortality, and the evaluation indexes were hazard ratios (HRs) and 95% confidence intervals (CIs). The interaction effect between hyperuricemia and anemia on the risk of all-cause mortality was assessed via relative excess risk due to interaction (RERI) and attributable proportion of interaction (AP). Subgroup analyses of age, gender, CVD, hypertension, DM, and cancer were also performed to assess this interaction effect.

Results

Among 3,678 eligible patients, 819 died from all causes. After adjusting for covariables, we found that CKD patients with anemia (HR = 1.72, 95%CI: 1.42-2.09) or hyperuricemia (HR = 1.21, 95%CI: 1.01-11.45) had a higher risk of all-cause mortality. There was a potential synergetic effect between anemia and hyperuricemia on all-cause mortality, with RERI of 0.630 and AP of 0.291. Moreover, this synergetic effect was also observed in ≥65 years old (AP = 0.330), male (AP = 0.355), hypertension (AP = 0.736), non-hypertension (AP = 0.281), DM (AP = 0.371), and cancer (AP = 0.391) subgroups.

Conclusion

A potential synergetic effect between anemia and hyperuricemia on all-cause mortality was found in patients with CKD. However, further studies are needed to clarify the causal relationship between them.

Serum ferritin and neutrophil-to-lymphocyte ratio predict all-cause mortality in patients receiving maintenance hemodialysis: a prospective study

Introduction: Maintenance hemodialysis is an effective treatment for end-stage renal disease patients. A critical factor contributing to the deterioration and death of maintenance hemodialysis patients is inflammation. Therefore, we focused on two inflammatory markers, serum ferritin and neutrophil-to-lymphocyte ratio, to speculate whether they could predict the prognosis of maintenance hemodialysis patients. Patients and methods: We followed 168 patients with maintenance hemodialysis from July 2019 to July 2022 with the endpoint of all-cause death or follow-up completion. Receiver operating characteristic curves were plotted to assess the values of serum ferritin, neutrophil-to-lymphocyte ratio and serum ferritin combined with neutrophil-to-lymphocyte ratio to predict the outcomes of maintenance hemodialysis patients. Kaplan-Meier survival curves were constructed to compare survival rates over time. Results: Receiver operating characteristic curves demonstrated that the best cut-off value of serum ferritin for predicting the prognosis of maintenance hemodialysis patients was 346.05 μg/L, and that of neutrophil-to-lymphocyte ratio was 3.225. Furthermore, a combination of both had a more excellent predicting value than either index (p < 0.05). Kaplan-Meier survival curve analyses revealed that low serum ferritin levels and low neutrophil-to-lymphocyte ratio had a higher probability of survival than high ferritin levels and high neutrophil-to-lymphocyte ratio, separately. Conclusion: Elevated serum ferritin and neutrophil-to-lymphocyte ratio are closely related to all-cause mortality among maintenance hemodialysis patients, for which they may be predictors of all-cause mortality. Additionally, the combination of the two has a much higher predictor value for the prognosis of maintenance hemodialysis patients.

Production of iron enriched Saccharomyces boulardii: impact of process variables

About half of the 1.62 billion cases of anemia are because of poor diet and iron deficiency. Currently, the use of iron-enriched yeasts can be used as the most effective and possible way to prevent and treat anemia due to the ability of biotransformation of mineral compounds into the organic form. In this research, for the first time, Saccharomyces (S.) boulardii was used for iron enrichment with the aim that the probiotic properties of yeast provide a potential iron supplement besides improving the bioavailability of iron. Also, due to its higher resistance than other Saccharomyces strains against stresses, it can protect iron against processing temperatures and stomach acidic-enzymatic conditions. So, the effect of three important variables, including concentration of iron, molasses and KH2PO4 on the growth and biotransformation of yeast was investigated by the Box-Behnken design (BBD). The best conditions occurred in 3 g/l KH2PO4, 20 g/l molasses and 12 mg/l FeSO4 with the highest biotransformation 27 mg Fe/g dry cell weight (DCW) and 6 g/l biomass weight. Such yeast can improve fermented products, provide potential supplement, and restore the lost iron of bread, which is a useful iron source, even for vegetarians-vegans and play an important role in manage with anemia. It is recommended that in future researches, attention should be paid to increasing the iron enrichment of yeast through permeabilizing the membrane and overcoming the structural barrier of the cell wall.

High Ferritin and Low Total Iron-Binding Capacity in Plasma Predict All-Cause Mortality During the First 3 Years of Hemodialysis in Patients with End-Stage Chronic Kidney Disease

Aim

To determine all-cause mortality rate and the predictive value of plasma ferritin and total iron-binding capacity (TIBC) concentrations for mortality during the first 3 years of hemodialysis in patients with end-stage chronic renal disease (ESRD).

Methods

We conducted a study on 174 ESRD patients (estimated Glomerular Filtration Rate < 15 mL/min/1.73m2). The plasma TIBC level was quantified by the ELISA method in all patients at the time before hemodialysis. Based on TIBC concentration, patients were divided equally into 2 groups. Each group had 87 patients. Patients were initiated on hemodialysis, and patients who died from any cause during the first 3 years of hemodialysis were recorded.

Results

The all-cause mortality rate of ESRD patients in the first 3 years of maintenance hemodialysis was 22.9%. Plasma high hs-CRP, high ferritin, and low TIBC concentrations were independent factors associated with all-cause mortality in the patients. Plasma ferritin (cut-off value = 454.2 ng/L) and TIBC (cut-off value = 39.84 µmol/L) were predictors of all-cause mortality, AUC is: 0.772; 0.723, p < 0.001.

Conclusion

Plasma ferritin and TIBC were good predictors of all-cause mortality in ESRD patients during the first 3 years of hemodialysis.

Is health-related quality of life trajectory associated with dialysis modality choice in advanced chronic kidney disease?

BACKGROUND

Patients with advanced chronic kidney disease have lower health-related quality of life (HRQOL) than the general population. There is uncertainty regarding patterns of HRQOL changes before dialysis initiation. This study aimed to characterise HRQOL trajectory and assess its potential association with intended dialysis modality.

METHODS

This prospective single-centre cohort study followed adults with an estimated glomerular filtration rate ≤15 mL/min/1.73 m2 for one year. Patients were allocated into one of two groups based on their intended treatment modality, 'home dialysis' (peritoneal dialysis or home haemodialysis (HD)) and 'other' (in-centre HD or conservative care). Follow-up was for up to 1 year or earlier if initiated on kidney replacement therapy or died. Kidney Disease Quality of Life - Short Form (KDQOL-SF) was completed every 6 months. Predictors of changes in KDQOL-SF components were modelled using mixed effect multivariable linear regressions.

RESULTS

One hundred and nine patients were included. At baseline, crude physical composite summary (PCS) (45 ± 10 vs. 39 ± 8) was higher in patients choosing home dialysis (n = 41), while mental composite summary (MCS) was similar in both groups. After adjustment, patients choosing home dialysis had an increase in MCS (B = 8.4 per year, p = 0.007) compared to those selecting in-centre HD/conservative care. This translates into an annual increase in MSC by 3 points for the 'home dialysis' group, compared to an annual decline by 5.4 points in the 'other' group. There was no difference in PCS trajectory through time.

CONCLUSIONS

Patients choosing home dialysis had improved MCS over time compared to those not selecting home dialysis. More work is needed to determine how differences in processes of care and/or unmeasured patient characteristics modulate this association.

The impact of diabetes, anemia, and renal function in the relationship between osteoporosis and fasting blood glucose among Taiwanese women: a cross-sectional study

BACKGROUND

The aim of this study was to investigate the association between fasting blood glucose and osteoporosis in women with diabetes, anemia, and renal function.

METHODS

The medical records of women who underwent a general health examination at a regional hospital in southern Taiwan were retrospectively reviewed. Logistic regression analysis was performed to assess the association between osteoporosis and fasting blood glucose separately for the eight subgroups (diabetes or non-diabetes, anemia or non-anemia, normal or decreased renal function), adjusting for other clinical characteristics and laboratory findings.

RESULTS

A total of 11,872 women were included in the study. Among women with diabetes, anemia, and decreased renal function, an increment of 10 mg/dL in fasting blood glucose was associated with an increased risk of osteoporosis (adjusted odds ratio [aOR] = 1.57, p = 0.004). Among women without diabetes, fasting blood glucose was significantly associated with an increased risk of osteoporosis in those with anemia and normal renal function (OR = 1.14, p = 0.023) and those without anemia and normal renal function (OR = 1.04, p = 0.015), but these associations were not significant after adjusting for other covariates.

CONCLUSIONS

Higher fasting blood glucose levels in women with diabetes, anemia, and decreased renal function were associated with an increased risk of osteoporosis. Clinicians should be vigilant about glucose control in patients with diabetes to reduce the risk of fracture.

Intravenous iron: an update

Iron deficiency is the most common nutritional deficiency worldwide, with significant adverse health consequences in the presence or absence of anaemia. Total dose intravenous iron replacement is recommended for replacement of iron in patients with severe iron deficiency, especially in the presence of anaemia, intolerance or inefficacy following oral iron, or states of inflammation where upregulation of hepcidin may impair gastrointestinal absorption of iron. Currently, available intravenous iron formulations have been demonstrated to have an excellent overall safety profile, but potential adverse effects, including skin staining, infusion-related reactions and hypophosphataemia, have been described. Knowledge of differences in administration and safety profiles of currently available iron formulations will allow appropriate prescription, counselling, as well as recognition and management of adverse events in patients requiring intravenous iron.

Biology of Anemia: A Public Health Perspective

Our goal is to present recent progress in understanding the biological mechanisms underlying anemia from a public health perspective. We describe important advances in understanding common causes of anemia and their interactions, including iron deficiency (ID), lack of other micronutrients, infection, inflammation, and genetic conditions. ID develops if the iron circulating in the blood cannot provide the amounts required for red blood cell production and tissue needs. ID anemia develops as iron-limited red blood cell production fails to maintain the hemoglobin concentration above the threshold used to define anemia. Globally, absolute ID (absent or reduced body iron stores that do not meet the need for iron of an individual but may respond to iron supplementation) contributes to only a limited proportion of anemia. Functional ID (adequate or increased iron stores that cannot meet the need for iron because of the effects of infection or inflammation and does not respond to iron supplementation) is frequently responsible for anemia in low- and middle-income countries. Absolute and functional ID may coexist. We highlight continued improvement in understanding the roles of infections and inflammation in causing a large proportion of anemia. Deficiencies of nutrients other than iron are less common but important in some settings. The importance of genetic conditions as causes of anemia depends upon the specific inherited red blood cell abnormalities and their prevalence in the settings examined. From a public health perspective, each setting has a distinctive composition of components underlying the common causes of anemia. We emphasize the coincidence between regions with a high prevalence of anemia attributed to ID (both absolute and functional), those with endemic infections, and those with widespread genetic conditions affecting red blood cells, especially in sub-Saharan Africa and regions in Asia and Oceania.

Association of iron therapy with incidence of chronic kidney disease

OBJECTIVE

We investigated the association of oral iron replacement with the incidence of chronic kidney disease (CKD) in a population with normal kidney function to study the effects of iron replacement on the development of new onset CKD.

METHODS

In a national cohort of US Veterans with no pre-existing CKD, we identified 33 894 incident new users of oral iron replacement and a comparable group of 112 780 patients who did not receive any iron replacement during 2004-2018. We examined the association of oral iron replacement versus no iron replacement with the incidence of eGFR <60 mL/min/1.73 m2 and the incidence of urine albumin creatinine ratio (UACR) ≥30 mg/g in competing risk regressions and in Cox models. We used propensity score weighing to account for differences in key baseline characteristics associated with the use of oral iron replacement.

RESULTS

In the cohort of 146 674 patients, a total of 18 547 (13%) patients experienced incident eGFR <60 mL/min/1.73 m2 , and 16 117 patients (11%) experienced new onset UACR ≥30 mg/g. Oral iron replacement was associated with significantly higher risk of incident eGFR <60 mL/min/1.73 m2 (subhazard ratio, 95% confidence interval [CI]: 1.3 [1.22-1.38], p < .001) and incident albuminuria (subhazard ratio, 95% CI: 1.14 [1.07-1.22], p < .001).

CONCLUSION

Oral iron replacement is associated with higher risk of new onset CKD. The long-term kidney safety of oral iron replacement should be tested in clinical trials.

New Clues to Cardiovascular Disease: Erythrocyte Lifespan

Determination of erythrocyte lifespan is an important part of the diagnosis of hemolytic diseases. Recent studies have revealed alterations in erythrocyte lifespan among patients with various cardiovascular diseases, including atherosclerotic coronary heart disease, hypertension, and heart failure. This review summarizes the progress of research on erythrocyte lifespan in cardiovascular diseases.

Effect of roxadustat on iron metabolism in patients with peritoneal dialysis: a real-world 24-week study

BACKGROUND

Roxadustat is an oral hypoxia inducing factor-prolyl hydroxylase inhibitor (HIF-PHI) that regulates iron metabolism in patients with chronic kidney disease (CKD) primarily by reducing hepcidin levels and mobilizing internal iron stores. More data are needed to demonstrate the efficacy of roxadustat in regulating iron metabolism in patients with peritoneal dialysis (PD) compared with erythropoiesis stimulating agents (ESAs).

METHODS

This prospective cohort study enrolled PD patients with a mean hemoglobin level of 60-100 g/L. All subjects were randomized into two groups at a ratio of 2:1 the roxadustat group (106 cases), and the ESA group (53 cases). The primary endpoint was the change in the iron biomarker levels and the proportion of patients with absolute iron deficiency and functional iron deficiency.

RESULTS

Compared with ESAs, roxadustat significantly decreased hepcidin level (difference, - 20.09 ng/mL; 95% CI, - 30.26 to - 9.92), attenuated the increase in serum soluble transferrin receptor (sTFR) level (difference, - 7.87 nmol/L; 95% CI, - 12.11 to - 3.64), and reduced the proportion of patients with functional iron deficiency (roxadustat, 11.43%; ESA, 33.33%). There was no significant difference in safety of the two groups over the duration of the study.

CONCLUSIONS

Compared with ESA group, roxadustat group showed significant differences in all iron biomarker levels except serum ferritin (sFt) and transferrin saturation (TSAT). These results suggest that roxadustat was superior to ESAs as a therapy for iron metabolism in PD patients.

TRIAL REGISTRATION

This study completed Chinese Clinical Trial Registration on March 4, 2022 (registration number: ChiCTR2200057231).

Association between iron status markers and kidney outcome in patients with chronic kidney disease

Several studies conducted in patients with various stages of chronic kidney disease (CKD) have investigated the association of iron status markers, such as transferrin saturation (TSAT) and serum ferritin, with kidney outcomes. However, the associations were inconsistent and remain strongly debated. Therefore, we aimed to investigate whether TSAT and serum ferritin levels were associated with kidney outcome in such a population. In this study, 890 patients who were admitted for the evaluation of and education for CKD were prospectively followed. Primary kidney outcome was a composite of doubling of serum creatinine, end-stage kidney disease, or death due to kidney failure. Participants were divided into quartiles (Q1-Q4) according to TSAT or serum ferritin levels. During a median follow-up period of 2.8 years, kidney events occurred in 358 patients. In the multivariable Cox analyses, compared with Q3 of TSAT, the hazard ratios (95% confidence intervals) for Q1, Q2, and Q4 were 1.20 (0.87, 1.66), 1.38 (1.01, 1.87), and 1.14 (0.82, 1.59), respectively. Compared with Q2 of serum ferritin, lower and higher quartiles had a significantly increased risk for kidney outcome; hazard ratios (95% confidence intervals) for Q1, Q3, and Q4 were 1.64 (1.18, 2.27), 1.71 (1.24, 2.37), and 1.52 (1.10, 2.10), respectively. A Fine-Gray model with death before kidney events as a competing risk showed results similar to the above. In CKD, lower and higher ferritin levels were independent risk factors for kidney disease progression.

Iron Status and Physical Performance in Athletes

Iron is an important mineral in the body, essential for muscle function and oxygen transport. Adequate levels of iron in the blood are necessary for athletes, as iron-deficiency anemia can reduce physical performance. Several studies have investigated iron status and supplementation in iron-deficient athletes, and determined how physical strain can change iron balance and markers related to iron status. The question of how to influence and optimize iron status, as well as other markers that can affect iron metabolism, has been less thoroughly investigated. Therefore, the aim of this review is to take a closer look at the importance of iron values, iron markers, and factors that can change iron metabolism for physical performance and the extent to which physical performance can be influenced in a positive or negative way. A systematic search of the PubMed database was performed, with the use of « iron» or «iron deficiency» or «hemoglobin» AND «athletes» AND «athletic performance» as a strategy of the search. After the search, 11 articles were included in the review after the application of inclusion and exclusion criteria. Major findings include that iron supplementation had the best effect in athletes with the lowest iron status, and effects on physical performance were mostly achieved in those who were originally in a deficit. Iron supplementation could be beneficial for optimal erythropoietic response during altitude training, even in athletes with normal iron stores at baseline, but should be performed with caution. Alteration of the hepcidin response can affect the use of existing iron stores for erythropoiesis. Energy intake, and the amount of carbohydrates available, may have an impact on the post-exercise hepcidin response. Optimal vitamin D and B12 levels can possibly contribute to improved iron status and, hence, the avoidance of anemia.

Serum and Tissue Lipocalin-2 Expression in Chronic Kidney Disease Pruritic Patients

BACKGROUND

Uremic pruritus is an irritating symptom for patients with end-stage kidney disease. Lipocalin-2 (LCN2) has relevant importance in several biological cellular processes and immunity. It is also a major player in the progression of many disorders, such as renal injury.

AIM

To evaluate LCN2 expression in chronic kidney disease (CKD) pruritic patients in serum together with immunohistochemical expression in skin samples and further correlation of their results with the studied clinicopathologic parameters.

MATERIALS AND METHODS

Serum level of LCN2 (assessed by enzyme-linked immunosorbent assay) and skin immunohistochemical expression were investigated in 25 CKD patients and 25 healthy controls. Ten patients were subjected to narrowband ultraviolet B phototherapy for 12 weeks then re-evaluated for serum and tissue LCN2 after therapy.

RESULTS

LCN2 expression was increased significantly in both the epidermis and dermal adnexa in CKD patients over controls. Also, serum LCN2 level was higher in patients than in healthy subjects and was significantly associated with itching severity, grades of CKD, urea, and creatinine serum level. Tissue and serum levels of LCN2 were significantly diminished in CKD patients following narrowband therapy along with improvement of the severity of pruritus.

CONCLUSIONS

The increased serum and tissue LCN2 expression in CKD pruritic patients and its pronounced decrease, in addition to the improvement of pruritus after treatment, suggest a major pathogenic role of LCN2 in uremic pruritus.

Implementation of a coagulation component into a phosphate kinetics model in haemodialysis therapy: A tool for detection of clotting problems?

A coagulation component should be considered in phosphate kinetics modelling because intradialytic coagulation of the extracorporeal circuit and dialyser might reduce phosphate removal in haemodialysis. Thus, the objective of this study was to add and evaluate coagulation as an individual linear clearance reduction component to a promising three-compartment model assuming progressive intradialytic clotting. The model was modified and validated on intradialytic plasma and dialysate phosphate samples from 12 haemodialysis patients collected during two treatments (HD1 and HD2) at a Danish hospital ward. The most suitable clearance reduction in each treatment was identified by minimizing the root mean square error (RMSE). The model simulations with and without clearance reduction were compared based on RMSE and coefficient of determination (R2 ) values. Improvements were found for 17 of the 24 model simulations when clearance reduction was added to the model. The slopes of the clearance reduction were in the range of 0.011-0.632/h. Three improvements were found to be statistically significant (|observed z value| > 1.96). A very significant correlation (R2  = 0.708) between the slopes for HD1 and HD2 was found. Adding the clearance reduction component to the model seems promising in phosphate kinetics modelling and might be explained, at least in part, by intradialytic coagulation. In future studies, the model might be developed further to serve as a potentially useful tool for the quantitative detection of clotting problems in haemodialysis. NEW FINDINGS: What is the central question of this study? The aim was to add an intradialytic coagulation component to a modified version of a promising three-compartment phosphate kinetics model. The hypothesis was that circuit and dialyser clotting can be modelled by an individual linear phosphate clearance reduction component during haemodialysis treatment. What is the main finding and its importance? Improvements were found for 17 of 24 model simulations when clearance reduction was added to the model. Thus, the kinetics model seems promising and could be a useful tool for the quantitative detection of clotting problems in haemodialysis patients.

Recent advances in iron encapsulation and its application in food fortification

Iron (Fe) is an important element for our body since it takes part in a huge variety of metabolic processes. However, the direct incorporation of Fe into food fortification causes a number of problems along with undesirable organoleptic properties. Thus, encapsulation has been suggested to alleviate this problem. This study first sheds more light on the Fe encapsulation strategies and comprehensively explains the results of Fe encapsulation studies in the last decade. Then, the latest attempts to use Fe (in free or encapsulated forms) to fortify foods such as bakery products, dairy products, rice, lipid-containing foods, salt, fruit/vegetable-based products, and infant formula are presented. Double emulsions are highly effective at keeping their Fe content and display encapsulation efficiency (EE) > 88% although it decreases upon storage. The encapsulation by gel beads possesses several advantages including high EE, as well as reduced and great Fe release in gastric and duodenal conditions, respectively. Cereals, particularly bread and wheat, are common staple foods globally; they are very suitable for food fortification by Fe derivatives. Nevertheless, the majority of Fe in flour is available as salts of phytic acid (IP6) and phytates, reducing Fe bioavailability in the human body. The sourdough process degrades IP6 completely while Chorleywood Bread Making Process and conventional processes decrease it by 75% in comparison with whole meal flour.

Alcohol intake, smoking, self-medication practices and burden of anaemia among traders in Tamale metropolis of Ghana

OBJECTIVE

Lifestyle choices including physical inactivity, smoking, abuse of alcohol and drugs, unhealthy diet are common among traders and market women and these behavioural activities predispose individuals to ill-health conditions including cardiovascular diseases and chronic anaemia. We evaluated lifestyle choices such as alcohol intake, smoking and resorting to self-medication among traders in the Tamale Central market in Ghana. We then associated these lifestyle choices with anaemia.

RESULTS

A total of 400 participants were recruited for this study. Haemoglobin (Hb) levels of participants were measured using Mission® Plus Hb meter and anaemia was diagnosed by Hb < 12 g/dl for non-pregnant females and Hb < 13 g/dl for males. Of the participants, a majority (69.3%) were males, and most of them (56.0%) were within 18-35 years age bracket. While alcohol intake and smoking were uncommon, self-medication was a common practice among the participants. Anaemia was a common condition; diagnosed in 44.5% of participants, but was independent of age, alcohol intake and smoking. However, anaemia was more common in females (χ2 = 15.9, p < 0.001) and was associated with self-medication (χ2 = 5.7, p = 0.017). We recommend that traders in the Tamale metropolis should seek routine health check-ups to help avert adverse health consequences associated with anaemia.

Factors Governing the Erythropoietic Response to Intravenous Iron Infusion in Patients with Chronic Kidney Disease: A Retrospective Cohort Study

BACKGROUND

Limited knowledge exists about factors affecting parenteral iron response. A study was conducted to determine the factors influencing the erythropoietic response to parenteral iron in iron-deficient anaemic patients whose kidney function ranged from normal through all stages of chronic kidney disease (CKD) severity.

METHODS

This retrospective cohort study included parenteral iron recipients who did not receive erythropoiesis-stimulating agents (ESA) between 2017 and 2019. The study cohort was derived from two groups of patients: those managed by the CKD team and patients being optimised for surgery in the pre-operative clinic. Patients were categorized based on their kidney function: Patients with normal kidney function [estimated glomerular filtration rate (eGFR) ≥ 60 mL/min/1.73 m2] were compared to those with CKD stages 3-5 (eGFR < 60 mL/min/1.73 m2). Patients were further stratified by the type of iron deficiency [absolute iron deficiency (AID) versus functional iron deficiency (FID)]. The key outcome was change in hemoglobin (∆Hb) between pre- and post-infusion haemoglobin (Hb) values. Parenteral iron response was assessed using propensity-score matching and multivariate linear regression. The impact of kidney impairment versus the nature of iron deficiency (AID vs. FID) in response was explored.

RESULTS

732 subjects (mean age 66 ± 17 years, 56% females and 87% White) were evaluated. No significant differences were observed in the time to repeat Hb among CKD stages and FID/AID patients. The Hb rise was significantly lower with lower kidney function (non-CKD and CKD1-2; 13 g/L, CKD3-5; 7 g/L; p < 0.001). When groups with different degrees of renal impairment were propensity-score matched according to whether iron deficiency was due to AID or FID, the level of CKD was found not to be relevant to Hb responses [unmatched (∆Hb) 12.1 vs. 8.7 g/L; matched (∆Hb) 12.4 vs. 12.1 g/L in non-CKD and CKD1-2 versus CKD3-5, respectively]. However, a comparison of patients with AID and FID, while controlling for the degree of CKD, indicated that patients with FID exhibited a diminished Hb response regardless of their level of kidney impairment.

CONCLUSION

The nature of iron deficiency rather than the severity of CKD has a stronger impact on Hb response to intravenous iron with an attenuated response seen in functional iron deficiency irrespective of the degree of renal impairment.

Iron-Deficiency Anemia in CKD: A Narrative Review for the Kidney Care Team

Anemia is a common complication of chronic kidney disease (CKD) and is associated with increased mortality and reduced health-related quality of life. Anemia is characterized by a decrease in hemoglobin, the iron-rich protein that the body uses for oxygen transport. Iron is required to produce hemoglobin, and disruptions in the iron homeostasis can lead to iron-deficiency anemia. Management of anemia in individuals with CKD is typically performed by a team of physicians, nurse practitioners, physician assistants, or registered nurses. Throughout the care continuum, the management can be enhanced by multidisciplinary care, and individuals with CKD can benefit from the involvement of other specialties, with dietitians/nutritionists playing an important role. However, a key area of unmet clinical need is how to assess and address iron-deficiency anemia. This review aims to provide an overview of iron-deficiency anemia in CKD and how this may be diagnosed and managed by the entire kidney care team, such as describing the mechanisms underlying iron homeostasis, the complications of iron-deficiency anemia, and the current challenges associated with its diagnosis and treatment in CKD. Opportunities for each multidisciplinary team member to add value to the care of individuals with CKD and iron-deficiency anemia are also described.

Iron and iron-related proteins in COVID-19

COVID-19 can cause detrimental effects on health. Vaccines have helped in reducing disease severity and transmission but their long-term effects on health and effectiveness against future viral variants remain unknown. COVID-19 pathogenesis involves alteration in iron homeostasis. Thus, a contextual understanding of iron-related parameters would be very valuable for disease prognosis and therapeutics.Accordingly, we reviewed the status of iron and iron-related proteins in COVID-19. Iron-associated alterations in COVID-19 reported hitherto include anemia of inflammation, low levels of serum iron (hypoferremia), transferrin and transferrin saturation, and high levels of serum ferritin (hyperferritinemia), hepcidin, lipocalin-2, catalytic iron, and soluble transferrin receptor (in ICU patients). Hemoglobin levels can be low or normal, and compromised hemoglobin function has been proposed. Membrane-bound transferrin receptor may facilitate viral entry, so it acts as a potential target for antiviral therapy. Lactoferrin can provide natural defense by preventing viral entry and/or inhibiting viral replication. Serum iron and ferritin levels can predict COVID-19-related hospitalization, severity, and mortality. Serum hepcidin and ferritin/transferrin ratio can predict COVID-19 severity. Here, serum levels of these iron-related parameters are provided, caveats of iron chelation for therapy are discussed and the interplay of these iron-related parameters in COVID-19 is explained.This synopsis is crucial as it clearly presents the iron picture of COVID-19. The information may assist in disease prognosis and/or in formulating iron-related adjunctive strategies that can help reduce infection/inflammation and better manage COVID-19 caused by future variants. Indeed, the current picture will augment as more is revealed about these iron-related parameters in COVID-19.

Association between anemia-related biomarkers and the adequacy of peritoneal dialysis in Chinese patients with chronic kidney disease

Objectives: The study aimed to examine the association of three anemia-related biomarkers with the adequacy of peritoneal dialysis (PD) in patients with chronic kidney disease (CKD). Methods: This study included 127 PD patients. The total Kt/V urea (Kt/V) was calculated according to the Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines. All patients were classified into two groups based on Kt/V, viz., adequate (Kt/V ≥1.7) and inadequate (Kt/V <1.7) groups. Effect sizes are expressed as odds ratios (ORs) and 95% confidence interval (CI). Results: After adjusting for age, gender, hypertension, diabetes, and PD duration, 20 g/L increment in hemoglobin (Hgb) was observed to significantly reduce the risk of inadequate PD by 19% (OR; 95% CI; P: 0.81; 0.70 to 0.95; 0.009), 5 g/L increment in the mean corpuscular hemoglobin concentration (MCHC) by 7% (0.93; 0.88 to 0.98; 0.009), and 5% increment in transferrin saturation (TS) by 23% (0.77; 0.64 to 0.94; 0.012). The gender-specific nomogram model was constructed by incorporating three significant anemia-related biomarkers and convenient influencing factors, and the prediction accuracy was good (concordance index (C-index): 0.686 for men and 0.825 for women). Conclusion: Our findings indicate that the deterioration of three anemia-related biomarkers (Hgb, MCHC, and TS) can precipitate the development of inadequate PD in Chinese patients with CKD.

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

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

Iron Parameters in Patients Treated with Roxadustat for Anemia of Chronic Kidney Disease

Roxadustat is a novel agent with a distinct mechanism of action compared to erythropoiesis-stimulating agents (ESAs) and a potentially different combination of effects on iron parameters. This narrative review describes the effects of roxadustat on iron parameters and on hemoglobin levels in the context of iron supplementation in patients with anemia of non-dialysis-dependent (NDD) or dialysis-dependent (DD) chronic kidney disease (CKD). Roxadustat use was associated with a greater reduction in serum ferritin levels than seen with ESAs and an increase in serum iron levels compared to a decrease with ESAs. Decreases in transferrin saturation in patients treated with roxadustat were relatively small and, in the case of patients with NDD CKD, not observed by Week 52. These changes reflect the concomitant increases in both serum iron and total iron-binding capacity. Compared to placebo and an ESA, roxadustat improved iron availability and increased erythropoiesis while requiring less intravenous iron use. Hepcidin levels generally decreased in patients who received roxadustat compared to baseline values in all CKD populations; these decreases appear to be more robust with roxadustat than with an ESA or placebo. The mechanisms behind the effects of roxadustat and ESAs on iron availability and stores and erythropoiesis appear to differ and should be considered holistically when treating anemia of CKD.

Jian-Pi-Yi-Shen formula restores iron metabolism from dysregulation in anemic rats with adenine-induced nephropathy

ETHNOPHARMACOLOGICAL RELEVANCE

Jian-Pi-Yi-Shen (JPYS) is a herbal decoction being used to relieve the symptoms of chronic kidney disease (CKD) and its complications, including anemia, for over twenty years. Nonetheless, it is unclear how JPYS influences renal anemia and iron metabolism.

AIM OF THE STUDY

An analysis of network pharmacology, chemical profiling, and in vivo experiments was conducted to identify the impact of JPYS on JAK2-STAT3 pathway and iron utilization in renal anemia and CKD.

MATERIALS AND METHODS

The chemical properties of JPYS and its exposed ingredients were detected in vivo. And based on the aforesaid chemical compounds, the potential targets and signaling pathways of JPYS for renal anemia treatment were predicted by network pharmacology. Afterward, an adenine-feeding animal model of CKD-related anemia was developed to verify the mechanism by which JPYS modulates iron recycling to treat renal anemia. Renal injury was estimated by serum creatinine (Scr), blood urea nitrogen (BUN), histopathological examinations and fibrosis degree. Western blot, enzyme-linked immunosorbent assay (ELISA), quantitative real-time polymerase chain reaction (qPCR) and immunohistochemistry approaches were utilized to assess the levels of JAK2, STAT3 and iron metabolism-related factors.

RESULTS

There were 164 active ingredients identified in JPYS, including prototypes and metabolites in vivo were identified in JPYS, and 21 core targets were found through network pharmacology based on topological characteristics. Combined with the core targets and pathway enrichment analysis, the majority of the candidate targets were associated with the JAK2-STAT3 signaling pathways. Experimental results indicated that JPYS treatment significantly decreased the expression of BUN and Scr, restored renal pathological damage, down-regulated fibrosis degree, and improved hematological parameters such as red blood cell, hemoglobin and hematocrit in CKD rats. Furthermore, JPYS significantly restored iron metabolism from dysregulation by increasing the levels of iron and ferritin in the serum, inhibiting the production of hepcidin in liver and serum, and regulating transferrin receptor 1 in bone marrow. Meanwhile, the expression of JAK2 and STAT3 was suppressed by JPYS treatment.

CONCLUSIONS

Based on these results, JPYS reduces hepcidin levels by inhibiting the activation of JAK2-STAT3 signaling, thereby protecting against iron deficiency anemia.

Synbiotic supplement for treatment of iron deficiency anaemia in haemodialysis patients: A randomized controlled trial

BACKGROUND

There is evidence that probiotics can increase the availability of iron. The aim of current study was to determine the effects of synbiotic supplementation on the haematological parameters and anaemia in haemodialysis patients.

METHODS

This study was a randomized, double-blind, placebo-controlled trial. Fifty patients were randomly selected from the haemodialysis section of Vaseii Hospital, Sabzevar, Iran. Subjects in the symbiotic and control groups received 2 capsules of synbiotic supplement or placebo, respectively, once a day for 8 weeks. Blood samples were divided into two test tubes in equal volumes. Blood haemoglobin, haematocrit, transferrin saturation, red blood cells (RBCs), and total iron binding capacity (TIBC) were measured with auto-analyser. Ferritin was determined using Sandwich enzyme-linked immunosorbent assay (ELISA).

RESULTS

Twenty tree patients in each group completed the study. Significant results were recorded in synbiotic groups regarding the concentration of blood haemoglobin, haematocrit, transferrin saturation, the number of RBCs, and serum ferritin compare to placebo group (P < .05). At the end of week 8, TIBC significantly decreased in synbiotic than placebo group (P < .05).

CONCLUSION

Synbiotic supplementation could be a safe and promising candidate in improving anaemia in CKD patients.

Iron Deficiency and Nephrotoxic Heavy Metals: A Dangerous Interplay?

Heavy metals are common in our environment, and all individuals are exposed to them to some extent. These toxic metals have several harmful effects on the body, including the kidney, which is a very sensitive organ. Indeed, heavy metal exposure has been linked to an increased risk of chronic kidney disease (CKD) and its progression, which may be explained by the well-established nephrotoxic effects of these metals. In this hypothesis and narrative literature review, we will shed light on the potential role that another highly common problem in patients with CKD, iron deficiency, may play in the damaging effects of heavy metal exposure in this patient group. Iron deficiency has previously been linked with an increased uptake of heavy metals in the intestine due to the upregulation of iron receptors that also take up other metals. Furthermore, recent research suggests a role of iron deficiency in the retention of heavy metals in the kidney. Therefore, we hypothesize that iron deficiency plays a crucial role in the damaging effects of heavy metal exposure in patients with CKD and that iron supplementation might be a strategy to combat these detrimental processes.

Ferric derisomaltose for the treatment of iron deficiency anemia with postpartum hemorrhage: Results of a single-arm, open-label, phase 3 study in Japan

AIM

Single-arm, open-label, phase 3 study to evaluate the efficacy and safety of ferric derisomaltose (FDI) for iron deficiency anemia (IDA) in Japanese women with postpartum hemorrhage (PPH).

METHODS

Postpartum women aged 20-39 years with serum ferritin <25.0 ng/ml, hemoglobin (Hb) <10.0 g/dl, and blood loss ≥500 ml within 24 h post-delivery were eligible to receive high-dose intravenous FDI. The primary endpoint was the maximum change in Hb concentration by Week 8. Key secondary endpoints included change in iron parameters and percentage of patients with a total Edinburgh Postnatal Depression Score (EPDS) ≥9. Safety assessments included treatment-emergent adverse events (TEAEs) and iron concentrations in maternal milk.

RESULTS

All (n = 21 [100.0%]) patients received the predetermined total iron dose by Day 8. Hb concentrations increased rapidly and significantly (p < 0.001) following FDI. Serum ferritin levels also increased rapidly and were maintained near or above the upper limit of normal reference value (250 ng/ml). Following FDI, two (9.5%) patients had a total EPDS score of ≥9. TEAEs occurred in 23 of 42 (54.8%) patients and neonates overall, including 18 of 21 (85.7%) patients and 5 of 21 (23.8%) neonates. TEAEs were mild in all adult patients and four neonates, and moderate in one neonate. Iron concentrations in maternal milk remained within normal reference values. Appropriate patient selection and patient-adjusted dosage selection facilitated safe and effective administration of high-dose (≥1000 mg) FDI.

CONCLUSIONS

Rapid and sustained improvements in Hb and iron stores occurred following FDI for IDA with PPH, with no new safety signals identified.

CLINICAL TRIAL IDENTIFIER

JapicCTI-194888.

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

Background

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

Aim

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

Methods

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

Results

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

Conclusion

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

Hypoxia-Inducible Factor Prolyl Hydroxylase Inhibitors and Iron Metabolism

The production of erythropoietin (EPO), the main regulator of erythroid differentiation, is regulated by hypoxia-inducible factor (HIF). HIF2α seems to be the principal regulator of EPO transcription, but HIF1α and 3α also may have additional influences on erythroid maturation. HIF is also involved in the regulation of iron, an essential component in erythropoiesis. Iron is essential for the organism but is also highly toxic, so its absorption and retention are strictly controlled. HIF also induces the synthesis of proteins involved in iron regulation, thereby ensuring the availability of iron necessary for hematopoiesis. Iron is a major component of hemoglobin and is also involved in erythrocyte differentiation and proliferation and in the regulation of HIF. Renal anemia is a condition in which there is a lack of stimulation of EPO synthesis due to decreased HIF expression. HIF prolyl hydroxylase inhibitors (HIF-PHIs) stabilize HIF and thereby allow it to be potent under normoxic conditions. Therefore, unlike erythropoiesis-stimulating agents, HIF-PHI may enhance iron absorption from the intestinal tract and iron supply from reticuloendothelial macrophages and hepatocytes into the plasma, thus facilitating the availability of iron for hematopoiesis. The only HIF-PHI currently on the market worldwide is roxadustat, but in Japan, five products are available. Clinical studies to date in Japan have also shown that HIF-PHIs not only promote hematopoiesis, but also decrease hepcidin, the main regulator of iron metabolism, and increase the total iron-binding capacity (TIBC), which indicates the iron transport capacity. However, concerns about the systemic effects of HIF-PHIs have not been completely dispelled, warranting further careful monitoring.

Promising novel therapeutic targets for kidney disease: Emphasis on kidney-specific proteins

Worldwide, around 850 million people are diagnosed with kidney disease but the available treatment options are still limited. Preclinical studies propose a plethora of druggable targets that can attenuate kidney disease and could qualify as novel therapeutic strategies, although most of these targets still await clinical testing. Here, we review some promising candidate targets for chronic kidney disease: intermedin, periostin, sirtuin, the cannabinoid receptor, Klotho, and uromodulin. For acute kidney injury, we discuss Apelin, Elabela, growth differentiation factor-15, Fyn kinase, and Klotho. Target selection for further clinical development should consider redundancies with the standard of care, potential synergistic effects with existing treatments, as well as the potential of additional effects on the cardiovascular system as a common comorbidity in patients with kidney disease.

Vascular calcification: Molecular mechanisms and therapeutic interventions

Vascular calcification (VC) is recognized as a pathological vascular disorder associated with various diseases, such as atherosclerosis, hypertension, aortic valve stenosis, coronary artery disease, diabetes mellitus, as well as chronic kidney disease. Therefore, it is a life-threatening state for human health. There were several studies targeting mechanisms of VC that revealed the importance of vascular smooth muscle cells transdifferentiating, phosphorous and calcium milieu, as well as matrix vesicles on the progress of VC. However, the underlying molecular mechanisms of VC need to be elucidated. Though there is no acknowledged effective therapeutic strategy to reverse or cure VC clinically, recent evidence has proved that VC is not a passive irreversible comorbidity but an active process regulated by many factors. Some available approaches targeting the underlying molecular mechanism provide promising prospects for the therapy of VC. This review aims to summarize the novel findings on molecular mechanisms and therapeutic interventions of VC, including the role of inflammatory responses, endoplasmic reticulum stress, mitochondrial dysfunction, iron homeostasis, metabolic imbalance, and some related signaling pathways on VC progression. We also conclude some recent studies on controversial interventions in the clinical practice of VC, such as calcium channel blockers, renin-angiotensin system inhibitions, statins, bisphosphonates, denosumab, vitamins, and ion conditioning agents.

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.

[Management of iron deficiency in chronic kidney disease: Review and proposed algorithm]

Iron deficiency is very common in chronic kidney disease, even before the dialysis stage. It is an independent factor of morbidity and mortality in patients with non-dialysis chronic kidney disease. During chronic kidney disease, iron deficiency is defined by a transferrin saturation <20% and/or a serum ferritin <100 μg/L. In France, about half of non-dialysis chronic kidney disease patients have absolute iron deficiency (transferrin saturation <20% and serum ferritin <100 μg/L) and/or functional iron deficiency (transferrin saturation <20% and serum ferritin >100 μg/L). Despite this, iron deficiency is usually not investigated. In fact, more than 60% of nephrologists do not assess iron status at least once a year. In addition, iron deficiency is rarely treated: only 12% of patients are prescribed oral or intravenous iron. Early detection and treatment are fundamental and should be systematic. In order to help improve the management of iron deficiency among non-dialysis chronic kidney disease patients, we propose an algorithm that takes into account current recommendations and the most recent data from the literature. Initial blood test requires the measurement of hemoglobin concentration, transferrin saturation and serum ferritin. A transferrin saturation <20% establishes the diagnosis of iron deficiency and the serum ferritin level points towards an absolute or functional deficiency. The combination of both values makes it possible to adapt the treatment, particularly in an inflammatory context where oral iron is not effective.

Biosimilar erythropoietin in anemia treatment (BEAT)-Efficacy and safety of a 1:1 dose conversion from EPREX® to EPIAO® in patients with end-stage renal disease on hemodialysis: A prospective, randomized, double blind, parallel group study

BACKGROUND

EPREX®/ERYPO®/PROCRIT® (epoetin alfa, Janssen-Cilag GmbH) was the first available recombinant human erythropoietin (rHuEPO) and was universally reference product as per the recommendation provided by European Medicines Agency. EPIAO® is a biosimilar formulation of EPREX®, and making it a 1:1 dose conversion from EPREX® according to recommendation of European Medicines Agency. This study evaluated the clinical efficacy and safety of EPIAO® in subjects with end-stage renal disease receiving hemodialysis after intravenous administration.

METHODS

This study was a multicenter, prospective, randomized, double-blind, parallel-group, 2-cohort, maintenance phase, therapeutic equivalence study to evaluate a 1:1 dose conversion from EPREX® to EPIAO® in terms of clinical efficacy and safety that was conducted at 20 sites in 2 countries in patients with end-stage renal disease on hemodialysis. Eligible subjects were treated with EPREX® (reference product of epoetin) for a period of at least 3 months before the treatment period, and then were randomly assigned to the group of EPREX® or EPIAO®. Primary endpoints were mean absolute change in hemoglobin level and mean absolute change in weekly epoetin dosage from baseline to 6 months after treatment with EPIAO®/EPREX® in parallel groups.

RESULTS

A total of 200 people received the random intervention and were included in the safety set. After 6, 9, and 12 months of treatment with EPIAO® or EPREX®, there were no significant differences in the hemoglobin levels of the 2 groups compared with baseline. The 95% confidence interval for the treatment difference was within the predetermined acceptable range: ±0.5 g/dL. There were no significant differences in the epoetin dosage of the 2 groups compared with the baseline. The 95% confidence interval for the treatment difference was within the predetermined acceptable range: ± 45 IU/kg. There were no significant differences in the incidence of adverse events between the EPIAO® and EPREX® groups. Most adverse events were mild to moderate and were reverted/resolved.

CONCLUSION

EPIAO® demonstrated promising effectiveness and manageable safety in patients with end-stage renal disease on hemodialysis.

Prevalence of anaemia in adults with chronic kidney disease in a representative sample of the United States population: analysis of the 1999-2018 National Health and Nutrition Examination Survey

Background

Population-based estimates of anaemia prevalence in patients with chronic kidney disease (CKD) vary, and data on the prevalence of severe anaemia of CKD are limited. This study examined the prevalence of anaemia and anaemia eligible for erythropoiesis-stimulating agent (ESA) treatment in patients with CKD in the USA.

Methods

National Health and Nutrition Examination Survey (NHANES) data from 1999-2000 to 2017-18 were used to determine the prevalence of diagnosed anaemia (haemoglobin <12 g/dL in women; <13 g/dL in men) and anaemia eligible for ESA treatment (haemoglobin <10 g/dL) in survey participants aged ≥18 years with stage 3-5 non-dialysis-dependent CKD (estimated glomerular filtration rate <60 mL/min/1.73 m²). The study objectives were to (i) obtain a more recent estimate of anaemia prevalence in patients with non-dialysis-dependent CKD and (ii) examine the characteristics of individuals with CKD and haemoglobin <10 g/dL.

Results

Of 51 163 eligible NHANES participants, 2926 (5.7%) with stage 3-5 CKD were included. In all participants, the weighted prevalences of anaemia and haemoglobin <10 g/dL were 25.3% and 1.9%, respectively. Mean haemoglobin levels decreased numerically between 1999 and 2012 and remained stable thereafter. The prevalence of anaemia and haemoglobin <10 g/dL increased with advancing CKD stage. The odds of haemoglobin <10 g/dL were significantly higher in stage ≥3B versus 3A and in non-Hispanic Blacks versus other races.

Conclusions

In our analysis, approximately 25% of individuals with stage 3-5 CKD in the USA had anaemia and approximately 2% had anaemia eligible for ESA treatment.

Iron Deficiency in Patients with Advanced Heart Failure

Background and Objectives: Iron deficiency (ID) is a common comorbidity in patients with heart failure. It is associated with reduced physical performance, frequent hospitalisations for heart failure decompensation, and high cardiovascular and overall mortality. The aim was to determine the prevalence of ID in patients with advanced heart failure on the waiting list for heart transplantation. Methods and Materials: We included 52 patients placed on the waiting list for heart transplantation in 2021 at our centre. The cohort included seven patients with LVAD (left ventricle assist device) as a bridge to transplantation implanted before the time of results collection. In addition to standard tests, the parameters of iron metabolism were monitored. ID was defined as a ferritin value <100 µg/L, or 100−299 µg/L if transferrin saturation (T-sat) is <20%. Results: ID was present in 79% of all subjects, but only in 35% of these patients anaemia was expressed. In the group without LVAD, ID was present in 82%, a median (lower−upper quartile) of ferritin level was 95.4 (62.2−152.1) µg/mL and mean T-sat was 0.18 ± 0.09. In LVAD group, ID was present in 57%, ferritin level was 268 (106−368) µg/mL and mean T-sat was 0.14 ± 0.04. Haemoglobin concentration was the same in patients with or without ID (133 ± 16) vs. (133 ± 23). ID was not associated with anaemia defined with regard to patient’s gender. In 40.5% of cases, iron deficiency was accompanied by chronic renal insufficiency, compared to 12.5% of the patients without ID. In the patients with LVAD, ID was present in four out of seven patients, but the group was too small for reliable statistical testing due to low statistical power. Conclusions: ID was present in the majority of patients with advanced heart failure and was not always accompanied by anaemia and renal insufficiency. Research on optimal markers for the diagnosis of iron deficiency, especially for specific groups of patients with heart failure, is still ongoing.

Unmet needs about iron deficiency in peritoneal dialysis: a Delphi consensus panel

Background

Anaemia and iron deficiency (ID) are common in chronic kidney disease (CKD) patients and related to outcomes. There is growing interest about the role of iron supplementation in CKD, particularly ferric carboxymaltose (FCM), also in relation to the use of erythropoiesis stimulating agents (ESAs). Despite a greater knowledge on ID management in patients receiving haemodialysis, a paucity of data exists about peritoneal dialysis (PD). Furthermore, the aim of this paper is to provide the results of a nationwide Italian survey about ID in PD using the Delphi method.

Methods

A list of 16 statements (48 items) was developed about four main topics: (1) approach to iron therapy in PD; (2) management experience about iron therapy in PD; (3) ESA and iron in PD; (4) pharmacoeconomic impact. Using the Delphi methodology, the survey was distributed online to 36 Italian nephrologists with expertise in PD, who rated their level of agreement with each item on a 5-point Likert scale. Consensus was predefined as more than 66% of the panel agreeing/disagreeing with any given statement.

Results

Twenty-five experts (70%) answered the survey. 35 items (73%) achieved a consensus (8 negative and 27 positive). In particular, the diagnosis of ID is widely known, but some doubts exist about how frequently test it. The use of I.V. iron seems to be routinary and can save money reducing the administration of ESAs. However, internal protocols are welcome.

Conclusions

Expert PD nephrologists know well the problem of ID and feel the necessity of shared protocols to optimize the iron therapy and consequently the use of ESAs.

Tetramethylpyrazine nitrone activates hypoxia-inducible factor and regulates iron homeostasis to improve renal anemia

Renal anemia is one of the most common complications of chronic kidney disease and diabetic kidney disease. Despite the progress made in recent years, there is still an urgent unmet clinical need for renal anemia treatment. In this research, we investigated the efficacy and mechanism of action of the novel tetramethylpyrazine nitrone (TBN). Animal models of anemia including the streptozotocin (STZ)-induced spontaneously hypertensive rats (SHR) and the cisplatin (CDDP)-induced C57BL/6J mice are established to study the TBN's effects on expression of hypoxia-inducible factor and erythropoietin. To explore the mechanism of TBN's therapeutic effect on renal anemia, cobalt chloride (CoCl2) is used in Hep3B/HepG2 cells to simulate a hypoxic environment. TBN is found to increase the expression of hypoxia-inducible factor HIF-1α and HIF-2α under hypoxic conditions and reverse the reduction of HIFs expression caused by saccharate ferric oxide (SFO). TBN also positively regulates the AMPK pathway. TBN stimulates nuclear transcription and translation of erythropoietin by enhancing the stability of HIF-1α expression. TBN has a significant regulatory effect on several major biomarkers of iron homeostasis, including ferritin, ferroportin (FPN), and divalent metal transporter-1 (DMT1). In conclusion, TBN regulates the AMPK/mTOR/4E-BP1/HIFs pathway, and activates the hypoxia-inducible factor and regulates iron homeostasis to improve renal anemia.