Effect of erythropoiesis-stimulating agents in acute ST-segment elevation myocardial infarction: a systematic review

The role of anemia on admission in acute coronary syndrome - An umbrella review of systematic reviews and meta-analyses

INTRODUCTION

The role of erythrocytes in the acute coronary syndrome (ACS) is complex. The aim of this review in terms of PICO (P: patients; I: intervention; C: comparison; O: outcome) was to summarize systematic reviews in patients (P) with acute coronary syndrome, evaluating the effects of (I) 1) iron deficiency, 2) administration of an erythropoiesis-stimulating agent (ESA), 3) anemia on admission, 4) red blood cell transfusion, 5) a restrictive transfusion strategy in comparison (C) to 1) no iron deficiency, 2) no ESA 3) no anemia on admission, 4) no red blood cell transfusion, 5) a liberal transfusion strategy on mortality (O).

METHODS

We used AMSTAR2 to assess the methodological quality of systematic reviews and grade the available research. The primary endpoint was all-cause mortality.

RESULTS

Using the data from 2,787,005 patients, the following conditions were associated with worse outcome in patients with ACS: anemia on admission (RR 2.08 95%CI 1.70-2.55) and transfusion (1.93 95%CI 1.12-3.34) of red blood cells. A liberal transfusion (RR 0.86 95%CI 0.70-1-05), administration of ESA (RR 0.55 95%CI 0.22-1.33) and iron deficiency (OR 1.24 95%CI 0.12-13.13) were not associated with altered all-cause mortality.

CONCLUSION

Patients suffering from ACS and anemia on admission are at particular risk for adverse outcome. There is evidence of associations between adverse outcomes and receiving red blood cell transfusions.

Are There Any Cardioprotective Effects or Safety Concerns of Erythropoietin in Patients With Myocardial Infarction? A Systematic Review

Myocardial infarction (MI) is a global cause of morbidity and mortality. MI is the outcome of a chronic process termed atherosclerosis, a buildup of fatty and other substances called plaques inside the coronary vessels, causing hardening and thickening of the arterial wall. Erythropoietin (EPO) is a pleiotropic cytokine released mainly by the kidneys in adults. Besides its well-known erythropoietic functions, EPO possesses anti-apoptotic, mitogenic, and angiogenic effects. This review aims to analyze the strength of any therapeutic or protective value of EPO on the heart and safety concerns regarding its administration in MI individuals.

This systematic review was performed based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. Four databases (PubMed, PubMed Central, Google Scholar, and Sciences Direct) were employed to search for articles published in the last 10 years. Focused studies were relevant articles in the English language, trials, reviews, meta-analyses, and studies with a control group. Following the quality assessment process, nine studies were eligible and hence were included in the review consisting of six randomized controlled trials and three systematic reviews and meta-analyses. Contrary to preclinical studies, EPO administration did not significantly have notable effects on mortality, major adverse cardiovascular events, or infarction size reduction. Significant left ventricle ejection fraction amelioration was not appreciated either. However, EPO seems to reduce the incidence of post-MI arrhythmias.

Challenging patient phenotypes in the management of anaemia of chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is often complicated by anaemia, which is associated with disease progression and increased hospital visits, decreased quality of life, and increased mortality.

METHODS

A comprehensive literature search of English language peer-reviewed articles in PubMed/MedLine published between 1998 and 2020 related to the treatment of anaemia of CKD was conducted. The United States Renal Database System and Dialysis Outcomes and Practice Patterns Study (DOPPS) data reports, the Centers for Disease Control and Prevention and the US Food and Drug Administration websites, and published congress abstracts in 2020 were surveyed for relevant information.

RESULTS

Subgroups of patients with anaemia of CKD present a clinical challenge throughout the disease spectrum, including those with end-stage kidney disease, advanced age or resistance to or ineligibility for current standards of care (ie, oral or intravenous iron supplementation, erythropoietin-stimulating agents and red blood cell transfusions). In addition, those with an increased risk of adverse events because of comorbid conditions, such as cardiovascular diseases or diabetes, comprise special populations of patients with an unmet need for interventions to improve clinical outcomes. These comorbidities must be managed in parallel and may have a synergistic effect on overall disease severity.

CONCLUSIONS

Several therapies provide promising opportunities to address gaps with a standard of care, including hypoxia-inducible factor prolyl hydroxylase inhibitors, which stimulate haematopoiesis through promoting modest increases in serum erythropoietin and improved iron homeostasis. The critical issues in the management of anaemia of CKD in these challenging phenotypes and the clinical utility of new therapeutic agents in development for the treatment of anaemia of CKD should be assessed and the information should be made available to healthcare providers.

Efficacy of IntraCoronary Erythropoietin Delivery BEfore Reperfusion-Gauging Infarct Size in Patients with Acute ST-segment Elevation Myocardial Infarction (ICEBERG)

Previous clinical studies have shown inconsistent results regarding the effect of erythropoietin in ST-segment elevation myocardial infarction (STEMI). This study investigated whether directed intracoronary infusion of darbepoetin-α into ischemic myocardium before reperfusion would reduce infarct size or post-infarct remodeling in STEMI patients.Eighty STEMI patients received one of the following treatments simultaneously with the first balloon inflation: intracoronary darbepoetin-α 300 μg (n = 40) or saline (n = 40), administered via the over-the-wire balloon system. The primary endpoint was infarct size estimated by serial cardiac enzyme levels after procedure. The secondary endpoints were (1) infarct size and proportion of salvaged myocardium measured with cardiac magnetic resonance (CMR) at baseline; (2) post-infarct remodeling (PIR), defined as an increase in left ventricular end-diastolic volume more than 20% at 4 months compared to the baseline on CMR; and (3) composite cardiovascular endpoints assessed at 4 months.The peak CK-MB [median 270.0 (interquartile range 139.8-356.3) versus 231.5 (131.0-408.5) ng/mL, P = 0.55] and troponin-I [128.5 (63.5-227.8) versus 109.0 (43.8-220.0) ng/mL, P = 0.52) ] did not differ between the darbepoetin-α and control group. Fifty-seven patients completed the baseline and 4-month follow-up CMR. There were no differences in infarct size [30.6 (18.1-49.8) versus 31.5 (22.5-47.3) cm³, P = 0.91), proportion of salvaged myocardium [26.7% (15.9-42.6%) versus 35.8% (22.4-48.8%), P = 0.12) or PIR (8.0% versus 6.7%, P = 0.62) between the two groups. Composite cardiovascular outcomes did not differ between the two groups.In conclusion, administration of intracoronary darbepoetin-α before reperfusion did not reduce infarct size or post-infarct remodeling in STEMI patients.

Erythropoiesis stimulating agents and reno-protection: a meta-analysis

Background

Erythropoiesis stimulating agents (ESAs) were proposed to enhance survival of renal tissues through direct effects via activation of EPO receptors on renal cells resulting in reduced cell apoptosis, or indirect effects via increased oxygen delivery due to increased numbers of Hb containing red blood cells. Thus through several mechanisms there may be benefit of ESA administration on kidney disease progression and kidney function in renal patients. However conflicting ESA reno-protection outcomes have been reported in both pre-clinical animal studies and human clinical trials. To better understand the potential beneficial effects of ESAs on renal-patients, meta-analyses of clinical trials is needed.

Methods

Literature searches and manual searches of references lists from published studies were performed. Controlled trials that included ESA treatment on renal patients with relevant renal endpoints were selected.

Results

Thirty two ESA controlled trials in 3 categories of intervention were identified. These included 7 trials with patients who had a high likelihood of AKI, 7 trials with kidney transplant patients and 18 anemia correction trials with chronic kidney disease (predialysis) patients. There was a trend toward improvement in renal outcomes in the ESA treated arm of AKI and transplant trials, but none reached statistical significance. In 12 of the anemia correction trials, meta-analyses showed no difference in renal outcomes with the anemia correction but both arms received some ESA treatment making it difficult to assess effects of ESA treatment alone. However, in 6 trials the low Hb arm received no ESAs and meta-analysis also showed no difference in renal outcomes, consistent with no benefit of ESA/ Hb increase.

Conclusions

Most ESA trials were small with modest event rates. While trends tended to favor the ESA treatment arm, these meta-analyses showed no reduction of incidence of AKI, no reduction in DGF or improvement in 1-year graft survival after renal transplantation and no significant delay in progression of CKD. These results do not support significant clinical reno-protection by ESAs.

Erythropoietin Reduces Post-PCI Arrhythmias in Patients With ST-elevation Myocardial Infarction

BACKGROUND

Arrhythmia is the foremost cause of sudden death after myocardial infarction (MI). Animal models have recently shown that erythropoietin (EPO) can reduce the incidence of arrhythmia after MI.

METHODS

We investigated the effects of administrating 33,000 IU EPO on the occurrence of post-MI arrhythmia in 40 patients with ST-elevation MI who were randomly assigned in either EPO or placebo groups. Arrhythmias were blindly documented using full 12-lead configuration during 24 hours after percutaneous coronary intervention (PCI) by a cardiologist. Afterward, CK-MB, hematologic, and hemodynamic data were examined within 2 weeks after MI.

RESULTS

A comparison made between the 2 groups showed significant differences in the incidence of arrhythmias (20% in EPO group and 35% in placebo group, P = 0.043). However, no significant differences in type of arrhythmias were observed between the groups. There was no significant difference between levels of CK-MB in the 2 groups during 24 hours (P = 0.186). Hematologic and hemodynamic data showed no significant changes 2 weeks after PCI.

CONCLUSION

High-dose administration of EPO in patients with ST-elevation MI who have been treated by primary PCI and standard antiplatelet therapy reduces the occurrence of arrhythmias. For clinical interpretation of the results, further well-designed trials are required.

Effect of high-dose erythropoietin on graft function after kidney transplantation: a meta-analysis of randomized controlled trials

PURPOSE

Current evidence suggests that preconditioning with erythropoietin (EPO) can protect against ischemia reperfusion injury in rodents. However, randomized controlled trials (RCTs) assessing the efficacy and safety of high-dose EPO in kidney transplantation have yielded inconclusive results. Herein, we performed a meta-analysis of RCTs to assess whether the administration of high-dose EPO can improve graft function and the potential adverse events.

METHODS

Relevant RCT studies that investigated high-dose EPO on graft function after kidney transplantation were comprehensively searched in Pubmed, Embase, and Cochrane Library until July 10, 2014. All statistical analyses were performed using Review Manager 5.0 and STATA 12.0.

RESULTS

A total of 4 RCTs involving 356 patients were identified. Comprehensively, a trend of reduction in the incidence of delayed graft function could be observed in the EPO group (EPO vs. placebo groups: RR=0.88); however, the result did not reach the significance level (95% CI, 0.72-1.08; P=0.21). Furthermore, no significant difference in the incidences of adverse events was observed between the two groups.

CONCLUSIONS

The current meta-analysis indicates that the administration of high-dose EPO is, to some extent, prone to protect kidney function without increasing the susceptibility to adverse events.

Erythropoietin in cardiac disease: effective or harmful?

Discovered as the primary regulator of erythropoiesis, erythropoietin (EPO) is involved in a broad variety of processes that play a major role in cardiovascular diseases. In particular, the antiapoptotic and pro-angiogenic properties of EPO have prompted a growing interest in the use of EPO for the treatment of myocardial infarction and heart failure. In a variety of myocardial ischemic injury animal models, EPO administration has been shown to acutely reduce infarct size, thereby preserving ventricular function. In addition, cardiac long-term effects of EPO, such as prevention of ventricular remodeling and heart failure, have been described. In recent years, several trials have tested the effects of recombinant human erythropoietin (rhEPO) administration in patients with myocardial infarction and chronic heart failure, in the attempt to translate the cardioprotection found in experimental models to human patients. In view of the generally controversial findings, in this updated review we provide an overview of the results of the most recent trials that investigated the role of erythropoiesis-stimulating agents (ESAs), including rhEPO and its analogue darbepoetin, in the treatment of acute myocardial infarction and heart failure. The problems related to safety and tolerability of ESA therapy are also discussed. Our analysis of the available literature demonstrates that the results of clinical studies in patients with cardiac disease are not uniform and the conclusions are contradictory. Further larger prospective studies are required to test clinical efficacy and safety of EPO.

High-dose erythropoietin in acute ST-segment elevation myocardial infarction: a meta-analysis of randomized controlled trials

OBJECTIVE

We sought to perform a meta-analysis to evaluate the potential influence of high-dose erythropoietin (EPO) on cardiac function parameters in patients with acute ST-segment elevation myocardial infarction (STEMI).

METHODS AND RESULTS

By searching PubMed, EMBASE, and the Cochrane Library (up to December 2012), seven randomized controlled trials (RCTs) reporting cardiac functional parameters with a total of 1,250 acute STEMI patients were identified. When applied to patients with acute STEMI, high-dose EPO was relatively safe and no increase in all-caused death and severe adverse effects were indicated. Estimates were pooled from fixed or random effects models. Compared with controls, high-dose EPO resulted in a slight but significant improvement in left ventricular ejection fraction of 1.02 % [95 % confidence interval (CI) 0.17-1.88, P = 0.019, I (2) = 0 %] and an improvement in left ventricular end-systolic volume of -4.61 ml (95 % CI -7.64 to -1.58, P = 0.003, I (2) = 27.7 %).

CONCLUSIONS

Available evidence suggested that high-dose EPO has limited cardio-protective effects in patients with STEMI. However, considering the relatively short follow-up durations and small patient populations in the current RCTs, the effects of high-dose EPO on clinical outcomes in patients with STEMI need to be evaluated in larger prospective RCTs of longer duration.

Impact of erythropoietin on intensive care unit patients

Anemia is common in intensive care unit (ICU) patients. Red blood cell (RBC) transfusions are mainstays of their treatment and can be life-saving. Allogeneic blood components inherently bear risks of infection and immune reactions. Although these risks are rare in developed countries, recombinant human erythropoietin (rhEpo) and other erythropoiesis-stimulating agents (ESAs) have been considered alternative anti-anemia treatment options. As summarized herein, however, most of the clinical studies suggest that ESAs are not usually advisable in ICU patients unless approved indications exist (e.g., renal disease). First, ESAs act in a delayed way, inducing an increase in reticulocytes only after a lag of 3-4 days. Second, many critically ill patients present with ESA resistance as inflammatory mediators impair erythropoietic cell proliferation and iron availability. Third, the ESA doses used for treatment of ICU patients are very high. Fourth, ESAs are not legally approved for general use in ICU patients. Solely in distinct cases, such as Jehovah's Witnesses who refuse allogeneic blood transfusions due to religious beliefs, ESAs may be considered an exceptional therapy.