Longitudinal assessments of erythropoietin-stimulating agent responsiveness and the association with specific clinical outcomes in dialysis patients

Erythropoiesis-stimulating agents and cardiovascular mortality: A systematic review and meta-analysis of 17 studies and 372,156 hemodialysis patients

Introduction

Prior studies on the association between erythropoiesis-stimulating agents (ESAs) and cardiovascular mortality in hemodialysis patients have yielded conflicting findings. We aimed to clarify this relationship through a systematic review and meta-analysis of current evidence.

Methods

We comprehensively searched major databases for observational and interventional studies on ESA use and cardiovascular mortality in hemodialysis patients published from 1980 to September 2023. Pooled risk ratios (RR) with 95 % confidence intervals (CI) were calculated using random-effects models. Sources of heterogeneity were explored through subgroup analyses and meta-regression. The study data were analyzed using Stata 15 software.

Findings

Upon conducting the initial search, we extracted 792 articles and, after screening and considering the research criteria, 17 studies with 372,156 participants were included in the meta-analysis. Overall, ESA use was associated with a 27 % increased risk of cardiovascular mortality (RR 1.27, 95 % CI: 1.15-1.40, p < 0.001). This risk varied by geographical location, with RRs of 1.27 (95 % CI: 1.14-1.41; p-value≤0.001) for America, 1.33 (95 % CI: 1.12-1.58; p-value = 0.001) for Asia, and 1.23 (95 % CI: 1.02-1.49; p-value = 0.028) for Europe. Importantly, a gender disparity was revealed, with studies involving a higher proportion of males showing greater risks (RR 1.51, 95 % CI: 1.25-1.83, p < 0.001) than female-predominant studies (RR 1.08, 95 % CI: 0.86-1.36, p < 0.001).

Conclusion

Our meta-analysis indicates ESA use is associated with heightened cardiovascular mortality in hemodialysis patients, especially in males. These findings have implications for optimizing dosing strategies while balancing efficacy and safety. Further research is warranted, particularly randomized controlled trials, to establish definitive ESA dosing guidelines.

Investigating the relationship between erythropoiesis-stimulating agents and mortality in hemodialysis patients: A systematic review and meta-analysis

BACKGROUND

In recent years, various studies have been conducted to investigate the relationship between erythropoiesis-stimulating agents (ESAs) and mortality in hemodialysis patients, who showed contradictory results. Therefore, this study aimed to investigate the relationship between ESAs and mortality in hemodialysis patients.

METHODS

The current study is a systematic review and meta-analysis based on observational and interventional studies published in the Web of Science, Cochrane Library, Science Direct, PubMed, Scopus, and Google Scholar databases between 1980 and the end of 2022. Jadad scale checklist and Newcastle Ottawa scale were used to evaluate the quality of articles. The study data were analyzed using Stata 15 software.

RESULTS

In the initial search, 3933 articles were extracted, and by screening and considering the research criteria, 68 studies were finally included in the meta-analysis. According to the meta-analysis results, the risk ratio (RR) of overall mortality in hemodialysis patients receiving ESAs was equal to 1.19 (95% CI: 1.16-1.23, P ≤ 0.001). The RR of mortality in patients aged 60 years and under was equal to 1.33 (1.15-1.55, P ≤ 0.001), in the age group over 60 years was equal to 1.13 (1.10-1.16, P ≤ 0.001), in randomized clinical trial studies was equal to 1.06 (0.80-1.40, P = 0.701), in cohort studies was equal to 1.20 (1.16-1.25, P ≤ 0.001), in American countries was equal to 1.19 (1.10-1.29, P ≤ 0.001), in Asian countries was equal to 1.15 (1.10-1.19, P ≤ 0.001), and in European countries was equal to 1.18 (1.05-1.34, P = 0.007).

CONCLUSION

The results of the study show that receiving ESAs is associated with a 19% increase in the risk of overall mortality in hemodialysis patients.

Clinical significance of a novel reticulocyte-based erythropoietin resistance index in HD patients: A retrospective study

INTRODUCTION

The erythropoietin resistance index (ERI) is an indicator of erythropoiesis-stimulating agent (ESA) responsiveness and is typically calculated using Hb. However, Hb does not directly reflect ESA-induced erythropoiesis because of its long-term nature. We thus designed a novel ERI calculated with reticulocyte Hb (RetHb), a real-time index, and investigated its association with mortality in HD patients.

METHODS

We calculated the ERI using the change in RetHb before and after ESA administration (ERI_ΔRetHb ) and retrospectively analyzed its association with 3-year all-cause mortality using Kaplan-Meier survival curves and Cox regression analyses.

RESULTS

A total of 102 patients were included. Patients with the highest ERI_ΔRetHb had the worst prognosis according to the Kaplan-Meier survival curves (Log-rank p = 0.02). Multivariate Cox regression analysis showed that the ERI_ΔRetHb was significantly and independently associated with all-cause mortality (hazard ratio: 9.82, 95% CI [1.50, 64.41], p = 0.02).

CONCLUSION

The ERI_ΔRetHb was significantly and independently associated with all-cause mortality in HD patients.

High Erythropoiesis Resistance Index Is a Significant Predictor of Cardiovascular and All-Cause Mortality in Chinese Maintenance Hemodialysis Patients

Background

Renal anemia is a common complication of hemodialysis patients. Erythropoietin (EPO) hyporesponsiveness has been recognized as an important factor to poor efficacy of recombinant human erythropoietin in the treatment of renal anemia. More importantly, increased erythropoiesis resistance index (ERI) may be associated with inflammation and increased mortality.

Objective

The objective of this research was to investigate correlated factors of EPO responsiveness and to clarify the relationships between EPO hyporesponsiveness and cardiovascular mortality and all-cause mortality among maintenance hemodialysis patients.

Methods

This prospective cohort study enrolled 276 maintenance hemodialysis patients for a 55-month follow-up to investigate the factors related to ERI and its relationship to all-cause mortality and cardiovascular mortality.

Results

ERI was positively correlated with predialysis serum high-sensitivity C-reactive protein (r = 0.234, p < 0.001), alkaline phosphatase (r = 0.134, p = 0.028), and ferritin (r = 0.155, p = 0.010) and negatively correlated with albumin (r = −0.206, p < 0.001) and creatinine (r = −0.232, p < 0.001). As multiple linear regression showed, predialysis serum albumin, high-sensitivity C-reactive protein, ferritin, and creatinine were independent correlated factors of ERI (p < 0.05). Kaplan–Meier curves showed that the cumulative incidences of both cardiovascular mortality and all-cause mortality were significantly higher in patients with ERI > 11.04 IU/kg/w/g/dL (both p < 0.01). The high ERI group was significantly associated with higher risk for all-cause mortality (OR 1.781, 95% CI 1.091 to 2.910, p = 0.021) and cardiovascular mortality (OR 1.972, 95% CI 1.139 to 3.417, p = 0.015) after adjusting for confounders.

Conclusions

Predialysis serum albumin, high-sensitivity C-reactive protein, ferritin, and creatinine were independent correlated factors of EPO responsiveness among maintenance hemodialysis patients. Patients with higher ERI values had a higher all-cause mortality rate and cardiovascular mortality rate.

Independent associations of vitamin D metabolites with anemia in patients referred to coronary angiography: the LURIC study

PURPOSE

Anemia and vitamin D deficiency are both frequent in adult patients. Whether low vitamin D metabolite levels are an independent risk factor for different subtypes of anemia remains to be studied in detail.

METHODS

In 3299 patients referred for coronary angiography, we investigated the association of 25-hydroxyvitamin D (25OHD) and 1,25-dihydroxyvitamin D [1,25(OH)₂D] with anemia [hemoglobin (Hb) <12.5 g/dl] of specific subtypes.

RESULTS

Compared with patients with 25OHD levels in the adequate range (50-125 nmol/l), patients with deficient 25OHD concentrations (<30 nmol/l; 33.6 % of patients) had 0.6 g/dl lower Hb levels. Hb values were 1.3 g/dl lower in patients with 1,25(OH)₂D levels <40 pmol/l (5.4 % of patients), compared with patients in the highest 1,25(OH)₂D category (>70 pmol/l). Of the participants, 16.7 % met the criteria for anemia. In multivariate-adjusted regression analyses, the odds ratios for anemia in the lowest 25OHD and 1,25(OH)₂D categories were 1.52 (95 % CI 1.15-2.02) and 3.59 (95 % CI 2.33-5.52), compared with patients with 25OHD levels in the adequate range and patients with 1,25(OH)₂D levels >70 pmol/l. The probability of anemia was highest in patients with combined 25OHD and 1,25(OH)₂D deficiency [multivariable-adjusted odds ratio 5.11 (95 % CI 2.66-9.81)]. Patients with anemia of chronic kidney disease had the highest prevalence of 25OHD deficiency and 1,25(OH)₂D concentrations of <40 pmol/l.

CONCLUSIONS

Low 25OHD and 1,25(OH)₂D concentrations are independently associated with anemia. Patients with poor kidney function are most affected. Interventional trials are warranted to prove whether administration of plain or activated vitamin D can prevent anemia.

How the Target Hemoglobin of Renal Anemia Should Be

Renal anemia is caused by the deficiency of endogenous erythropoietin (Epo) due to renal dysfunction. We think that it is possible to slow the progression of chronic kidney disease (CKD) in case we initiate Epo early in pre-dialysis patients, especially in the non-diabetic population. Erythropoiesis stimulating agent (ESA) treatments targeting mild anemia (10-12 g/dl) can decrease the risk of occurrence of cardiovascular disease (CVD) in patients with hypertension, diabetes mellitus and congestive heart failure. As the large randomized controlled trials such as Cardiovascular Risk Reduction by Early Anemia Treatment with Epoetin Beta, Correction of Hemoglobin and Outcomes in Renal Insufficiency and Trial to Reduce Cardiovascular Events with Aranesp Thearpy in the Western countries suggested, we do not recommend high doses of ESA to achieve the target hemoglobin (Hb) level. The target Hb of >13 g/dl might lead to increase in the risk of CVD although maintaining a high Hb of >12 g/dl without ESA is not harmful for CKD patients. It is desirable to determine the target Hb in dialysis patients depending on their ages. Renal anemia should be monitored constantly to start ESA and iron replacement therapy at an appropriate time, while avoiding their excess in order to minimize the occurrence of CVD and other complications. Taken all the international guidelines and our clinical experiences together, we should consider administration of ESA when the Hb level becomes <11 g/dl in pre-dialysis patients and <10 g/dl in dialysis patients.