Low transferrin saturation (TSAT) and high ferritin levels are significant predictors for cerebrovascular and cardiovascular disease and death in maintenance hemodialysis patients

Transferrin levels are associated with malnutrition markers in hemodialysis patients in KwaZulu-Natal, South Africa

INTRODUCTION

Malnutrition is a global phenomenon and may be contributing to the increasing size of the hemodialysis (HD) population in South Africa and is affecting morbidity and clinical outcomes. Our study assessed whether transferrin could be a possible marker for malnutrition in the HD population.

METHODS

Clinical parameters (including skinfold thickness and mid-upper arm circumference [MUAC]) and laboratory markers (including transferrin and hemoglobin) were measured during a six-month period in a sample of 59 HD patients.

RESULTS

Linear regression analysis showed that MUAC (p = 0.027) as well as skinfold thickness (p = 0.021) had a significant association with transferrin levels within the HD participants. There was no significant association between transferrin levels or MUAC with hemoglobin levels (p = 0.075). Furthermore, the study found that decreased transferrin levels (< 2.15 g/dL to 3.80 g/dL) were closely related to malnutrition in the malnutrition distribution groups within the study, with 97.7% of HD participants being classified in one of the malnutrition groups.

CONCLUSION

Thus, transferrin levels are a valuable marker for malnutrition within the HD patient population and can be included along with clinical assessment parameters such as MUAC and skinfold thickness as primary indicators for malnutrition.

Endothelial dysfunction and cardiovascular risk in post-COVID-19 patients after 6- and 12-months SARS-CoV-2 infection

INTRODUCTION

SARS-CoV-2 infection causes severe endothelial damage, an essential step for cardiovascular complications. Endothelial-colony forming cells (ECFCs) act as a biomarker of vascular damage but their role in SARS-CoV-2 remain unclear. The aim of this study was to assess whether the number of ECFCs and angiogenic biomarkers remained altered after 6 and 12-months post-infection and whether this imbalance correlated with the presence of long-COVID syndrome and other biological parameters measured.

METHODS

Seventy-two patients were recruited at different time-points after overcoming COVID-19 and thirty-one healthy controls. All subjects were matched for age, gender, BMI, and comorbidities. ECFCs were obtained from peripheral blood and cultured with specific conditions.

RESULTS

The results confirm the presence of a long-term sequela in post-COVID-19 patients, with an abnormal increase in ECFC production compared to controls (82.8% vs. 48.4%, P < 0.01) that is maintained up to 6-months (87.0% vs. 48.4%, P < 0.01) and 12-months post-infection (85.0% vs. 48.4%, P < 0.01). Interestingly, post-COVID-19 patients showed a significant downregulation of angiogenesis-related proteins compared to controls indicating a clear endothelial injury. Troponin, NT-proBNP and ferritin levels, markers of cardiovascular risk and inflammation, remained elevated up to 12-months post-infection. Patients with lower numbers of ECFC exhibited higher levels of inflammatory markers, such as ferritin, suggesting that ECFCs may play a protective role. Additionally, long-COVID syndrome was associated with higher ferritin levels and with female gender.

CONCLUSIONS

These findings highlight the presence of vascular sequela that last up to 6- and 12-months post-infection and point out the need for preventive measures and patient follow-up.

Absolute iron deficiency, coronary artery calcification and cardiovascular mortality in maintenance haemodialysis patients

AIM

The effects of iron on vascular calcification in rats and vascular smooth muscle cells were recently reported, but clinical studies on iron and vascular calcification are scant. We studied the associations of absolute iron deficiency, coronary artery calcification and mortality in patients with maintenance haemodialysis (MHD).

METHODS

Transferrin saturation (TSAT), ferritin, mean corpuscular haemoglobin (MCH) and Agatston coronary artery calcium score (CACS) were studied at baseline in MHD patients and followed up for 3 years. Cox proportional hazard analyses for mortality and linear regression analyses for CACS were performed.

RESULTS

In 306 patients, the median age was 67 (56-81) years, dialysis duration was 76 (38-142) months, and diabetes prevalence was 42.5%. Fifty-two patients had died by 3 years. Patients with absolute iron deficiency (TSAT <20% and ferritin <100 ng/mL) (n = 102) showed significantly higher CACS (p = .0266) and C-reactive protein (p = .0011), but a lower frequency of iron formulation administration compared with patients without absolute iron deficiency at baseline (n = 204). Absolute iron deficiency was a significant predictor for 3-year cardiovascular (CV) mortality (hazard ratio: 2.08; p = .0466), but not for 3-year all-cause mortality. CACS was significant predictor for both 3-year CV and all-cause mortality (p <.05). Absolute iron deficiency and MCH were significant determinants of CACS (p < .05).

CONCLUSION

MHD patients with absolute iron deficiency showed significantly higher CACS than others, and absolute iron deficiency was a significant risk factor for coronary artery calcification and 3-year CV mortality in MHD patients, but was not a significant predictor for 3-year all-cause mortality.

Impact of transferrin saturation on cardiovascular events in non-dialysis-dependent chronic kidney disease patients treated with darbepoetin alfa

BACKGROUND

Although the widespread use of long-acting erythropoiesis-stimulating agents (ESAs) has facilitated the improvement of anemia in patients with chronic kidney disease (CKD), the improvement in prognosis has not been fully demonstrated. Iron deficiency is associated with the development of cardiovascular diseases (CVDs), and the relative iron deficiency induced by erythropoiesis-stimulating agents may prevent the improvement of prognosis. Therefore, we investigated the association between iron deficiency and cardiovascular events during long-acting erythropoiesis-stimulating agent therapy using transferrin saturation (TSAT), which is less susceptible to inflammation than ferritin.

METHODS

This study included 1040 patients with non-dialysis-dependent CKD, aged ≥ 20 years, with a glomerular filtration rate < 60 mL/min/1.73 m2 and hemoglobin < 11 g/dL, who were treated with darbepoetin alfa for 96 weeks. The patients were recruited in the BRIGHTEN Trial, a multicenter, prospective, observational study conducted to evaluate erythropoiesis-stimulating agent resistance to darbepoetin alfa in treating anemia in non-dialysis-dependent CKD in a clinical setting. The association between transferrin saturation and the cumulative incidence of cardiovascular events was evaluated using the Kaplan-Meier method. To calculate the hazard ratio (HR), 95% confidence intervals (CI) and the Cox proportional hazards model were used.

RESULTS

Survival curve analysis for cardiovascular events indicated that patients with transferrin saturation ≥ 30% had a significantly better prognosis, with an adjusted hazard ratio of 0.34 (95% confidence interval 0.22-0.52). Stratified analysis revealed that patients with transferrin saturation of 30-40% had a significantly lower risk of cardiovascular events than those with transferrin saturation of 20-30%, even after a multivariate-adjusted hazard ratio of 0.33 (95% confidence interval 0.21-0.54).

CONCLUSION

Patients with CKD and transferrin saturation of 30-40% had significantly fewer cardiovascular events than those with transferrin saturation of 20-30% among patients treated with long-acting erythropoiesis-stimulating agents. Therefore, it may be useful to maintain higher transferrin saturation from the viewpoint of erythropoiesis-stimulating agent responsiveness and the reduction of cardiovascular events.

The treatment effects and cardiovascular events of high-dose intravenous iron for hemodialysis patients with renal anemia: A systematic review and meta-analysis

BACKGROUND

Hemodialysis patients are common to have renal anemia in the nephrology practice. For the renal anemia, the high-dose iron from the intravenous route is an important treatment option. We can understand the treatment effects and cardiovascular events of high-dose intravenous iron reviewing the randomized clinical trials.

METHODS

We compared the high-dose and low-dose iron treatments to find if the high-dose intravenous iron can influence the hematological parameters more significantly than the low-dose iron. The cardiovascular events were also analyzed for the high-dose iron treatment. Six studies with a total of 2422 renal anemia patients under hemodialysis were enrolled. We focused the outcomes of hemoglobin, transferrin saturation percentage, ferritin, erythropoietin dose, and cardiovascular events.

RESULTS

The high-dose intravenous iron might be associated with a greater number of ferritin, transferrin saturation percentage, and hemoglobin. In addition, the erythropoietin dose was less needed to maintain the ideal hemoglobin range in the high-dose intravenous iron group.

CONCLUSIONS

In current meta-analysis, the high-dose intravenous iron might show the superior effects on the ferritin, transferrin saturation percentage, and hemoglobin levels and needed dose of erythropoietin when compared to low-dose iron treatment.

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.

Risk Factors for Thromboembolic Events in Patients With Dialysis-Dependent CKD: Pooled Analysis of Phase 3 Roxadustat Trials in Japan

INTRODUCTION

Thromboembolic events have occurred in clinical trials of roxadustat. This post hoc analysis explored potential factors related to thromboembolic events in dialysis-dependent patients treated with roxadustat in four phase 3 clinical trials in Japan.

METHODS

Thromboembolic events with onset before and after week 12 were evaluated. Baseline risk factors for thromboembolic events were investigated by Cox regression analyses. Nested case-control analyses using conditional logistic models with matched pairs of case-control data explored relationships between thromboembolic events and laboratory parameters.

RESULTS

Of the 444 patients, 56 thromboembolic events were observed in 44 patients during ≤ 52 weeks of treatment. The proportion of venous and arterial thromboembolic events gradually increased after week 12. Baseline risk factors included hemodialysis (vs peritoneal dialysis), advanced age (≥ 65 years), shorter dialysis vintage (< 4 months), and history of thromboembolism. The absence of concomitant intravenous or oral iron therapy (including ferric citrate) was associated with thromboembolic events before week 12 (hazard ratio 11.25; 95% confidence interval [CI] 3.36-37.71; vs presence). Case-control analysis revealed that low average transferrin saturation (< 10%; unadjusted odds ratio [OR] 6.25; 95% CI 1.52-25.62; vs ≥ 20%), high average transferrin level (≥ 2.5 g/L; unadjusted OR 4.36; 95% CI 1.23-15.39; vs < 2.0 g/L), and high average roxadustat dose (≥ 150 mg; unadjusted OR 5.95; 95% CI 1.07-33.16; vs < 50 mg) over the previous 8 weeks before the event onset were associated with thromboembolic events after week 12. However, adjustment for iron status extinguished the significant relationship between roxadustat dose and events. Multivariate case-control analysis showed that increased transferrin from baseline (≥ 1.0 g/L; adjusted OR 7.85; 95% CI 1.82-33.90; vs < 0.5 g/dL) and decreased mean corpuscular volume (< - 2 fL; adjusted OR 5.55; 95% CI 1.73-17.83; vs ≥ 0 fL) were associated with increased risk of thromboembolic events.

CONCLUSION

In addition to established risk factors, iron deficiency may be related to thromboembolic events. Graphical Abstract available for this article.

TRIAL REGISTRATION

NCT02780726, NCT02952092, NCT02780141, NCT02779764.

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.

Association of Estimated Total Body Iron with All-Cause Mortality in Japanese Hemodialysis Patients: The Miyazaki Dialysis Cohort Study

Iron deficiency/excess may be associated with worse prognosis in patients undergoing hemodialysis. This study ascertained the association of the estimated total body iron (TBI) with mortality in patients receiving hemodialysis. Multicenter clinical data collected in the Miyazaki Dialysis Cohort Study from 943 patients receiving hemodialysis were analyzed after stratification into tertile categories by baseline TBI-estimated as the heme iron plus iron storage from ferritin levels. The primary outcome was a 5-year all-cause mortality; hazard ratios of the TBI-all-cause mortality association were estimated using Cox models adjusted for potential confounders, including clinical characteristics, laboratory, and drug data, wherein patients with high TBI were the reference category. The receiver operating characteristic (ROC) curve analyses of TBI, serum ferritin levels, and transferrin saturation were performed to predict all-cause mortality; a total of 232 patients died during the follow-up. The low TBI group (<1.6 g) had significantly higher hazard ratios of mortality than the high TBI group (≥2.0 g). As ROC curve analyses showed, TBI predicted mortality more accurately than either levels of serum ferritin or transferrin saturation. Lower TBI increases the mortality risk of Japanese hemodialysis patients, and further studies should examine whether iron supplementation therapy that avoids low TBI improves prognosis.

Survival in hemodialysis in Brazil according to the source of payment for the treatment: Public Healthcare System (SUS) versus private insurance

INTRODUCTION

Brazil has the largest public and universal healthcare system in the world, but little is known about the outcomes of patients on hemodialysis (HD) in the country according to the source of funding for the treatment.

OBJECTIVE

To compare the profile and survival of patients under HD treatment funded by the Public Healthcare System (SUS) to those with private insurance.

METHODS

Retrospective analysis of adults undergoing HD between 2012 and 2017 in 21 dialysis centers in Brazil that provided both by the SUS and private health insurance. Participants, regardless of the paying source, received similar dialysis treatment. Data were censored after 60 months of follow-up or at the end of 2019.

RESULTS

4,945 patients were included, 59.7% of which were financed by the SUS. Patients financed by SUS, compared to those with private insurance, were younger (58 vs. 60 years; p < 0.0001) and with a lower prevalence of diabetes (35.8% vs. 40.9%; p < 0.0001). The 60-month survival rates in these groups were 51.1% and 52.1%, respectively (p = 0.85). In the analysis of the subdistribution proportional hazard ratio by the Fine-Gray model, including adjustment for concurrent outcomes, a significant increase in the risk ratio for death was found (1.22 [95% confidence interval 1.04 to 1.43]) in patients with treatment funded by the SUS.

CONCLUSIONS

Patients on HD with treatment funded by the SUS have a higher adjusted risk of death when compared to those with private insurance, despite similar dialysis treatment. Factors not directly related to dialysis therapy could explain this difference.

Assessment of the Efficacy of a Low-Dose Iron Supplement in Restoring Iron Levels to Normal Range among Healthy Premenopausal Women with Iron Deficiency without Anemia

(1) Background: Iron deficiency without anemia (IDWA) is a prevalent health concern in premenopausal women. Oral supplementation of iron may be a viable solution to improve blood-iron status in women; however, the effects of a high-dose iron-supplement regimen have been associated with gastrointestinal side effects. Therefore, the purpose of the present study was to evaluate the effectiveness of a low-dose liquid fermented iron-bisglycinate supplement (LIS) on improving blood-iron status in premenopausal women with IDWA without increasing constipation or gastrointestinal distress. (2) Methods: 85 premenopausal women with IDWA (ferritin < 70 ng/dL and hemoglobin > 11.0 g/dL) took a LIS (27 mg) or a placebo (PLA) for 8 weeks. Blood draws were taken at Wk0 and Wk8 of the study to measure serum-iron markers. In addition, surveys of gastrointestinal distress were administered at Wk0, Wk4, and Wk8 while the profile of mood states (POMS) was surveyed at Wk0 and Wk8. (3) Results: Compared to the placebo, the LIS was able to increase serum ferritin (p = 0.03), total serum iron (p = 0.03), and mean corpuscular volume (p = 0.02), while exhibiting no significant interaction in subjective gastrointestinal distress (p > 0.05). No significant effects were detected for POMS (p > 0.05). (4) Conclusions: Supplementing with LIS appears to improve blood-iron status without causing significant gastrointestinal distress in premenopausal women with IDWA.

Sobrevida na hemodiálise no Brasil de acordo com a fonte pagadora do tratamento: Sistema Único de Saúde versus convênio privado

Resumo Introdução: O Brasil possui o maior sistema público e universal de saúde do mundo, mas pouco se sabe sobre os desfechos dos pacientes em hemodiálise (HD) no país de acordo com a fonte de financiamento do tratamento. Objetivo: Comparar o perfil e a sobrevida dos pacientes que têm o tratamento de HD custeado pelo Sistema Único de Saúde (SUS) com aqueles com convênio privado. Métodos: Análise retrospectiva dos adultos incidentes em HD entre 2012 e 2017 em 21 centros de diálise no Brasil que atendiam tanto pelo SUS quanto por convênios privados. Os participantes, independentemente da fonte pagadora, receberam tratamento dialítico semelhante. Os dados foram censurados com 60 meses de acompanhamento ou ao final de 2019. Resultados: Foram incluídos 4945 pacientes, sendo 59,7% financiados pelo SUS. Os pacientes financiados pelo SUS, em comparação aos que tinham convênio privado, eram mais jovens (58 vs 60 anos; p < 0,0001) e com menor prevalência de diabetes (35,8% vs 40,9%; p < 0,0001). As taxas de sobrevida, em 60 meses nesses grupos foram de 51,1% e 52,1%, respectivamente (p = 0,85). Na análise da razão de risco proporcional de subdistribuição pelo modelo de Fine-Gray, incluindo ajuste para desfechos concorrentes, foi encontrado um aumento significativo na razão de risco para morte (1,22 [intervalo de confiança de 95% 1,04 a 1,43]) nos pacientes com tratamento custeado pelo SUS. Conclusões: Pacientes em HD com tratamento custeado pelo SUS têm um risco ajustado de morte mais elevado do que aqueles com convênio privado, apesar do tratamento dialítico semelhante. Fatores não relacionados diretamente à terapia dialítica poderiam justificar esta diferença.

Effects of hypoxia-inducible factor-prolyl hydroxylase inhibitors vs. erythropoiesis-stimulating agents on iron metabolism in non-dialysis-dependent anemic patients with CKD: A network meta-analysis

OBJECTIVE

To compare the effects of five hypoxia-inducible factor-prolyl hydroxylase domain inhibitors (HIF-PHIs), two erythropoiesis-stimulating agents (ESAs), and placebo on iron metabolism in renal anemia patients with non-dialysis-dependent chronic kidney disease (NDD-CKD).

METHOD

Five electronic databases were searched for studies. Randomized controlled clinical trials comparing HIF-PHIs, ESAs, and placebo in NDD-CKD patients were selected. The statistical program used for network meta-analysis was Stata/SE 15.1. The main outcomes were the change in hepcidin and hemoglobin (Hb) levels. The merits of intervention measures were predicted by the surface under the cumulative ranking curve method.

RESULTS

Of 1,589 original titles screened, data were extracted from 15 trials (3,228 participants). All HIF-PHIs and ESAs showed greater Hb level-raising ability than placebo. Among them, desidustat demonstrated the highest probability of increasing Hb (95.6%). Hepcidin [mean deviation (MD) = -43.42, 95%CI: -47.08 to -39.76], ferritin (MD= -48.56, 95%CI: -55.21 to -41.96), and transferrin saturation (MD = -4.73, 95%CI: -5.52 to -3.94) were decreased, while transferrin (MD = 0.09, 95%CI: 0.01 to 0.18) and total iron-binding capacity (MD = 6.34, 95%CI: 5.71 to 6.96) was increased in HIF-PHIs versus those in ESAs. In addition, this study observed heterogeneity in the ability of HIF-PHIs to decrease hepcidin. Compared with darbepoetin, only daprodustat (MD = -49.09, 95% CI: -98.13 to -0.05) could significantly reduce hepcidin levels. Meanwhile, daprodustat also showed the highest hepcidin-lowering efficacy (84.0%), while placebo was the lowest (8.2%).

CONCLUSION

For NDD-CKD patients, HIF-PHIs could ameliorate functional iron deficiency by promoting iron transport and utilization, which may be achieved by decreasing hepcidin levels. Interestingly, HIF-PHIs had heterogeneous effects on iron metabolism.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=242777, Identifier CRD42021242777.

Low-Dose Oral Iron Replacement Therapy Is Effective for Many Japanese Hemodialysis Patients: A Retrospective Observational Study

Western guidelines recommend the use of intravenous iron supplementation for hemodialysis patients. However, in Japanese patients with well-controlled inflammation, iron replacement may be achieved with oral iron supplementation. This study involved 108 courses in 77 outpatient hemodialysis patients who received low-dose oral iron replacement therapy. Data from baseline to week 28 of treatment were analyzed to identify factors associated with effectiveness. Changes over time in erythrocyte- and iron-related parameters and erythropoiesis-stimulating agent (ESA) dose were investigated in the effective group. A total of 84 courses (77.8%) satisfied the effectiveness criteria. Compared with the effective and ineffective groups, only C-reactive protein (CRP) was significantly different (p < 0.01). ROC curve analysis with efficacy as the endpoint showed a CRP cut point value of ≤0.1 mg/dL (area under the curve, 0.69; 95% confidence interval, 0.57−0.81). The relationship between serum ferritin and hemoglobin fluctuation by reducing the ESA dose showed a positive correlation (p < 0.001). In the ESA maintenance group, the serum ferritin gradually increased and then remained constant at about 60 ng/mL. Our data suggest that patients with CRP ≤ 0.1 mg/dL may benefit from low doses of oral iron supplementation. Approximately 60 ng/mL serum ferritin may be sufficient during stable hematopoiesis.

Sex and N-terminal pro B-type natriuretic peptide: The potential mediating role of iron biomarkers

BACKGROUND

Levels of N-terminal pro B-type natriuretic peptide (NT-proBNP), a marker of heart failure and cardiovascular risk, are generally higher in women than men. We explored whether iron biomarkers mediate sex differences in NT-proBNP levels.

METHODS

We included 5,343 community-dwelling individuals from the Prevention of Renal and Vascular Endstage Disease study. With linear regression analyses, we investigated the association of sex and iron biomarkers with NT-proBNP levels, independent of adjustment for potential confounders. The assessed iron biomarkers included ferritin, transferrin saturation (TSAT), hepcidin, and soluble transferrin receptor (sTfR). Next, we performed mediation analyses to investigate to which extent iron biomarkers influence the association between sex and NT-proBNP.

RESULTS

Of the included 5,343 participants, the mean standard deviation age was 52.2 ± 11.6 years and 52% were females. After adjustment for potential confounders, women compared to men, had higher NT-proBNP (β = 0.31; 95%CI = 0.29, 0.34), but lower ferritin (β = -0.37; 95%CI = -0.39, -0.35), hepcidin (β = -0.22, 95%CI = -0.24, -0.20), and TSAT (β = -0.07, 95% CI = -0.08, -0.06). Lower ferritin (β = -0.05, 95%CI = -0.08, -0.02), lower hepcidin (β = -0.04, 95%CI = -0.07, -0.006), and higher TSAT (β = 0.07; 95%CI = 0.01, 0.13) were associated with higher NT-proBNP. In mediation analyses, ferritin and hepcidin explained 6.5 and 3.1% of the association between sex and NT-proBNP, respectively, while TSAT minimally suppressed (1.9%) this association.

CONCLUSION

Our findings suggest that iron biomarkers marginally explain sex differences in levels of NT-proBNP. Future studies are needed to explore causality and potential mechanisms underlying these pathways.

Evaluating the safety and efficacy of daprodustat for anemia of chronic kidney disease: a meta-analysis of randomized clinical trials

PURPOSE

Anemia of chronic kidney disease (CKD) has traditionally been treated with recombinant human erythropoietin (rhEPO). Recently, daprodustat, a hypoxia-inducible factor prolyl-hydroxylase inhibitor, has also been shown to increase hematocrit. It remains unclear whether daprodustat or rhEPO should be the treatment of choice for anemia of CKD. We aimed to assess the efficacy and cardiovascular safety of daprodustat versus rhEPO in CKD patients.

METHODS

Online databases were queried in April 2022 for articles comparing the efficacy and safety of daprodustat in DD-CKD and NDD-CKD subgroups. Results from trials were pooled using a random-effects model.

RESULTS

Data on 8245 CKD patients from eight clinical trials were included. Our results show that in comparison to rhEPO, daprodustat maintained the same efficacy in increasing hemoglobin levels in both the DD-CKD (MD: 0.10; 95% CI [- 0.13,0.34]; p = 0.50) and NDD-CKD (MD: - 0.01; 95% CI [- 0.38,0.35]; p = 0.95) subgroups. Daprodustat significantly lowered hepcidin levels and significantly increased TIBC in both subgroups. Additionally, daprodustat significantly reduced the incidence of major adverse cardiovascular events (MACE) (RR: 0.89; 95% CI: 0.89-0.98; p = 0.02) and its myocardial infarction (MI) component (RR: 0.74; 95% CI: 0.59-0.92; p = 0.006) in the DD-CKD subgroup.

CONCLUSION

Daprodustat has similar efficacy compared to rhEPO for the treatment of anemia of CKD. On treatment, the reduced experience of MACE was reported in DD-CKD patients as compared to rhEPO. Furthermore, effects on iron metabolism varied by parameter, with daprodustat being superior to rhEPO in some cases and inferior in others.

A systematic review and meta-analysis of abnormalities in hematological and biochemical markers among Bangladeshi COVID-19 cases

Background and Aims

Abnormalities in hematological and biochemical markers are assumed to be associated with the progression of COVID-19 disease. This meta-analysis was performed to assess the consequences of abnormalities of biomarkers (D-dimers, C-reactive protein [CRP], serum ferritin, lactate dehydrogenase [LDH], random blood sugar [RBS], absolute neutrophil count [ANC], neutrophil to lymphocyte ratio (NLR), serum creatinine, and hemoglobin) in the Bangladeshi COVID-19 patients.

Methods

The data of biomarker levels in Bangladeshi COVID-19 patients were gathered from five databases: PubMed, ScienceDirect, Web of Science, Google Scholar and Bangladesh Journals Online between January 2020 to March 2022. Review Manager 5.4 was used for the meta-analysis, and Egger's test and Begg-Mazumdar's rank correlation were used to investigate publication bias.

Results

This study included 1542 patients with 567 severe and 975 nonsevere statuses. Based on the accumulated data synthesis, there is a strong correlation between disease severity and different biomarkers, including D-dimer, CRP, ferritin, LDH, RBS, NLR, and serum creatinine (MD = 1.16, p = 0.0004; MD = 22.97, p = 0.003; MD = 419.26, p < 0.00001; MD = 118.37, p = 0.004; MD = 1.96, p = 0.02; MD = 1.26, p = 0.02; and MD = 0.31, p = 0.008, respectively). A significantly decreased correlation was observed for hemoglobin levels in severe COVID-19 patients (MD = -0.73, p = 0.10).

Conclusion

The elevated biomarkers level was noticed in severe cases compared to nonsevere patients, revealing that D-dimer, CRP, ferritin, LDH, RBS, NLR, and serum creatinine are significantly correlated to COVID-19 severity. Only lower hemoglobin level was found to be associated with COVID-19 severity.

The interaction analysis between advanced age and longer dialysis vintage on the survival of patients receiving maintenance hemodialysis

Objective

To compare the all-cause mortality of aged and younger patients undergoing maintenance hemodialysis (MHD) over the long or short term, and to identify independent risk factors.

Methods

We performed a retrospective cohort study using the medical records of 181 patients undergoing MHD. We compared the clinical characteristics and laboratory data of survivors and participants who died, according to their age and the duration of MHD. Binary stepwise logistic regression was used to identify independent risk factors for all-cause mortality.

Results

Cardiovascular and cerebrovascular diseases were the principal causes of mortality. The number of aged participants with hypertensive nephropathy as their primary kidney disease was significantly higher than the number of younger participants. The proportion with chronic glomerulonephritis was significantly higher for participants undergoing long-term MHD. Logistic regression analysis revealed that low body mass index, single-pool Kt/V, serum albumin, platelet count, and total iron-binding capacity; and high intact parathyroid hormone and N terminal pro B type natriuretic peptide were independent risk factors for all-cause mortality.

Conclusions

Aged patients are more susceptible to hypertensive nephropathy than younger patients. In addition, the survival of patients with chronic glomerulonephritis undergoing MHD is superior to that of those with hypertensive or diabetic nephropathy.

Efficacy and Safety of Daprodustat Vs rhEPO for Anemia in Patients With Chronic Kidney Disease: A Meta-Analysis and Trial Sequential Analysis

Introduction: Daprodustat, a novel hypoxia-inducible factor prolyl-hydroxylase inhibitor (HIF-PHI), its efficacy and safety remain unclear. Thus, we conducted this meta-analysis aiming at investigating its efficacy and safety on the treatment of patients with chronic kidney disease (CKD)-related anemia.

Methods: We systematically searched for relevant studies in PubMed, Embase, Cochrane Library and Clinical Trial Registries databases from inception until December 2021. We selected randomized controlled trials comparing daprodustat with recombinant human erythropoietin (rhEPO) in anemia patients with CKD with or without dialysis.

Results: Seven studies including 7933 patients met the inclusion criteria. For both nondialysis-dependent (NDD-) CKD and dialysis-dependent (DD-) CKD patients, the pooled results showed that there was no significant difference in the changes in hemoglobin levels between the daprodustat and rhEPO groups (mean difference (MD) = −0.01, 95% confidence interval (CI) = −0.38, 0.35, p = 0.95; MD = 0.15, 95% CI = −0.29, 0.60, p = 0.50; respectively). In addition, a significant increase in transferrin saturation (TSAT), total iron binding capacity (TIBC) and total iron was observed in daprodustat groups compared with rhEPO groups in DD-CKD patients (p < 0.05). As for safety, the overall frequency of adverse events was similar between the daprodustat and rhEPO groups in DD-CKD patients (relative risk (RR) = 0.99, 95%CI = 0.92, 1.06, p = 0.76), and the trial sequential analysis (TSA) confirmed this result. But for NDD-CKD patients, the incidence of adverse events in the daprodustat groups was significantly higher than that of rhEPO groups (RR = 1.04, 95%CI = 1.01,1.07, p = 0.02), while the TSA corrected this result. No trend of increasing incidence of serious adverse events was found in all daprodustat treated patients, but the TSA could not confirm this result.

Conclusion: Although daprodustat was noninferior to rhEPO in correcting anemia in both NDD-CKD and DD-CKD patients, it seemed to have a better effect on optimizing iron metabolism in DD-CKD patients. Daprodustat may be a promising alternative for the treatment of anemia in patients with CKD. However, due to the lack of included studies, future researches are needed to further evaluate the therapeutic effect of daprodustat.

Systematic Review Registration:https://www.crd.york.ac.uk/prospero/, identifier CRD42021229636.

Post-mortem liver and bone marrow iron quantification in haemodialysis patients: A prospective cohort study

Background

Magnetic resonance liver scans indicate that iron overload is common in haemodialysis (HD) patients. However, histological evidence is scarce.

Methods

Liver biopsy and bone marrow aspirate were obtained in the first 24h post mortem from 21 adult HD patients. Biochemical liver iron content (LIC) was quantified by electrothermal atomization atomic absorption spectrophotometry. Tissue iron deposition was graded in the liver and bone marrow using Scheuer and Gale's criteria, respectively.

Findings

Median LIC was 42.5 (22.9-69.7) μmol/g and the majority (n=11; 57%) had mild to moderate liver iron overload (LIC >36 μmol/g). Scheuer grade was 2 (1-3) and 13 (62%) of liver biopsies had increased (> 1) iron deposition. In the bone marrow, median Gale's grade was 3 (3-4) and 9 (45%) patients had increased (>3) iron content.

Contrary to old autopsy studies, done in the pre-erythropoiesis-stimulating agents (ESAs) era, both liver and bone marrow were iron replete and showed a positive correlation (r=0.71, p<0.001).

Ferritin proved to have a good diagnostic accuracy for liver iron overload (0.87 95% CI 0.71-1.00) with an optimal cut-off value of 422 ng/ml. Haemoglobin was negatively associated with both LIC (r= -0.46, p=0.04) and iron content in the bone marrow (p=0.04). Patients with increased LIC had higher resistance to ESAs (p=0.02), yet no association with previous IV iron therapy.

Interpretation

In the majority of HD patients there was iron accumulation in both the liver and bone marrow that associated with anaemia severity and resistance to ESAs, suggesting a blocking mechanism of iron's utilization.

Funding

None.

Characteristics and predictors of mortality on haemodialysis in Brazil: a cohort of 5,081 incident patients

Background

Although Brazil has one of the largest populations on haemodialysis (HD) in the world, data regarding patients’ characteristics and the variables associated with risk of death are scanty.

Methods

This is a retrospective analysis of all adult patients who initiated on maintenance HD at 23 dialysis centres in Brazil between 2012 and 2017. Patients were censored after 60 months of follow-up or at the end of 2019.

Results

A total of 5,081 patients were included in the analysis. The median age was 59 years, 59.4% were men, 37.5% had diabetes as the cause of kidney failure. Almost 70% had a central venous catheter (CVC) as the initial vascular access, about 60% started dialysis in the hospital, and fluid overload (FO) by bioimpedance assessment was seen in 45% of patients. The 60-month survival rate was 51.4%. In the Cox regression analysis, being older (P<0.0001), starting dialysis in the hospital (P=0.016), having diabetes as the cause of kidney failure (P=0.001), high alkaline phosphatase (P=0.005), CVC as first vascular access (P=0.023), and FO (P<0.0001) were associated with higher death risk, whereas higher body mass index (P=0.015), haemoglobin (P=0.004), transferrin saturation (P=0.002), and serum albumin (P<0.0001) were associated with better survival. The same variables, except initial CVC use (P=0.14), were associated with death risk in an analysis of subdistribution proportional hazards ratio including the competing outcomes.

Conclusions

The present study gives an overview of a large HD population in a developing country and identifies the main predictors of mortality, including some potentially modifiable ones, such as unplanned initiation of dialysis in the hospital and fluid overload.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-022-02705-x.

Long-acting erythropoiesis-stimulating agent (ESA) induces physiological erythropoiesis via improvement of iron availability

PURPOSE

Previous studies reported that the long-acting erythropoiesis-stimulating agent (ESA) significantly suppresses the expression of hepcidin, which regulates iron availability. In this study, we compared the iron availability for erythropoiesis between short and long-acting ESA over a long period.

METHODS

We enrolled 69 hemodialysis patients in this study. All patients were treated with short-acting ESA (epoetin-α or epoetin-β) for the first 30 months. Then, all patients switched to long-acting ESA (continuous erythropoietin receptor activator-methoxy polyethylene glycol-epoetin beta) for the next 30 months. We measured their blood levels of Hb, ferritin, iron, total iron-binding capacity, intact-parathyroid hormone, calcium, phosphate, albumin, and highly sensitive CRP level.

RESULTS

There was no significant change in the dose of short or long-acting ESA during the study period. Compared with the short-acting ESA period, the mean hemoglobin (Hb) and transferrin saturation levels were significantly increased in the long-acting ESA period (from 10.3 ± 0.2 to 10.6 ± 0.3 g/dL). On the other hand, the mean serum ferritin level (from 72 ± 22.2 to 56.3 ± 14 ng/mL) and the dose of IV iron (from 108 ± 63 to 53 ± 27 mg/month) were significantly decreased in the long-acting ESA period.

CONCLUSION

In this study, we found that anemia treatment with long-acting ESA attenuated the iron utilization for erythropoiesis and maintained target Hb levels without requiring a higher dose of IV iron or ESA.

The Impact of Intravenous Iron Supplementation on Hematinic Parameters and Erythropoietin Requirements in Hemodialysis Patients

INTRODUCTION

Anemia is one of the most common complications of chronic kidney disease (CKD). As a result of the side effects of high doses of recombinant human erythropoietin (rhEPO) and the differences in the standard dose of the injectable iron, this study aimed to evaluate the effect of high and low intravenous iron supplementation on hematinic parameters and EPO requirements in patients under hemodialysis.

METHODS

This multicenter, randomized, double-blind clinical trial was conducted on 60 patients with CKD admitted to Sina and 29 Bahman hospitals in Tabriz, Iran in 2019-2020 to undergo hemodialysis. In the two studied groups, low (100 mg/week) and high (400 mg/week) doses of iron were administered and subjects were followed up for 6 months. The incidence of acute myocardial ischemia, stroke, and mortality during 6 months was recorded.

RESULTS

The required rhEPO dosage (mg/week) to maintain hemoglobin levels between 10 and 12 g/dL in the high-dose iron group was significantly decreased during the follow-up period (52,129.03 ± 23,810 vs. 45,760 ± 20,978.71, P ≤ 0.028). Transferrin saturation (TSAT) index had a significant upward trend after iron injection and significant correlations with the serum levels of Fe (r ≥ 0.353, P ≤ 0.007), ferritin (r ≥ 0.315, P ≤ 0.016), and total iron binding capacity (r ≥ 0.219, P < 0.050) during the follow-up period in the studied groups.

CONCLUSION

High-dose intravenous iron (400 mg/week) can reduce the mean dose of rhEPO requirements and increase the TSAT index over a period of 6 months in hemodialysis patients. High-dose IV iron administration can decrease cardiovascular events in hemodialysis patients with iron deficiency anemia.