Preschool Assessment of Preterm Infants Treated With Darbepoetin and Erythropoietin

Early High-Dose Erythropoietin and Cognitive Functions of School-Aged Children Born Very Preterm

Importance

Children born very preterm are at risk for long-term neurodevelopmental sequelae. Prophylactic high-dose recombinant human erythropoietin (rhEpo) shortly after birth has not been shown to improve cognitive, motor, and behavioral development at 2 and 5 years.

Objective

To investigate whether early high-dose rhEpo is associated with better executive functions and processing speed-late-maturing cognitive functions-in school-aged children born very preterm.

Design, Setting, and Participants

This single-center cohort study was a prospective, observational follow-up study of a multicenter neonatal clinical trial; 365 children born very preterm (mean gestational age, 29.3 weeks [range, 26.0-31.9 weeks]) who had been enrolled in the Swiss EPO Neuroprotection Trial at birth between 2005 and 2012, and who were included in the primary outcome analyses at 2 years, were eligible to be recruited for the EpoKids study between 2017 and 2021 when they were at school age. Term-born children were additionally recruited and included in a control group. Data were analyzed between May and September 2022.

Exposure

Administration of rhEpo (3000 IU/kg) or placebo (saline, 0.9%) intravenously 3 times within the first 2 days of life as part of the Swiss EPO Neuroprotection Trial.

Main Outcome and Measures

A comprehensive neuropsychological test battery assessed executive functions and processing speed, and parents reported on their child's executive functions in everyday life to test the hypothesis that early high-dose rhEpo administration is associated with better cognitive outcomes at school age.

Results

In the EpoKids study, 214 children born very preterm (58.6% of 365 children in eligible cohort) were assessed at a mean age of 10.4 years (range, 6.9-13.4 years); 117 (54.7%) were boys. There was no evidence that the 117 children who had received rhEpo differed from the 97 children who had received placebo in any of the 15 executive function and processing speed tests, nor in parent-rated executive functions (estimates ranged from -0.138 to 0.084, all 95% CIs included 0). Irrespective of rhEpo or placebo allocation, children born very preterm scored lower on 11 of 15 executive function and processing speed tests than term-born peers (estimates ranged from 0.112 to 0.255, 95% CIs did not include 0).

Conclusion and Relevance

This study found no evidence for a positive association between prophylactic early high-dose rhEpo administration and long-term neurodevelopmental outcomes after very preterm birth. These results suggest that a comprehensive approach, including pharmacological and nonpharmacological prevention and intervention strategies, is needed to support these children's neurodevelopmental outcome.

Chorioamnionitis disrupts erythropoietin and melatonin homeostasis through the placental-fetal-brain axis during critical developmental periods

Introduction: Novel therapeutics are emerging to mitigate damage from perinatal brain injury (PBI). Few newborns with PBI suffer from a singular etiology. Most experience cumulative insults from prenatal inflammation, genetic and epigenetic vulnerability, toxins (opioids, other drug exposures, environmental exposure), hypoxia-ischemia, and postnatal stressors such as sepsis and seizures. Accordingly, tailoring of emerging therapeutic regimens with endogenous repair or neuro-immunomodulatory agents for individuals requires a more precise understanding of ligand, receptor-, and non-receptor-mediated regulation of essential developmental hormones. Given the recent clinical focus on neurorepair for PBI, we hypothesized that there would be injury-induced changes in erythropoietin (EPO), erythropoietin receptor (EPOR), melatonin receptor (MLTR), NAD-dependent deacetylase sirtuin-1 (SIRT1) signaling, and hypoxia inducible factors (HIF1α, HIF2α). Specifically, we predicted that EPO, EPOR, MLTR1, SIRT1, HIF1α and HIF2α alterations after chorioamnionitis (CHORIO) would reflect relative changes observed in human preterm infants. Similarly, we expected unique developmental regulation after injury that would reveal potential clues to mechanisms and timing of inflammatory and oxidative injury after CHORIO that could inform future therapeutic development to treat PBI. Methods: To induce CHORIO, a laparotomy was performed on embryonic day 18 (E18) in rats with transient uterine artery occlusion plus intra-amniotic injection of lipopolysaccharide (LPS). Placentae and fetal brains were collected at 24 h. Brains were also collected on postnatal day 2 (P2), P7, and P21. EPO, EPOR, MLTR1, SIRT1, HIF1α and HIF2α levels were quantified using a clinical electrochemiluminescent biomarker platform, qPCR, and/or RNAscope. MLT levels were quantified with liquid chromatography mass spectrometry. Results: Examination of EPO, EPOR, and MLTR1 at 24 h showed that while placental levels of EPO and MLTR1 mRNA were decreased acutely after CHORIO, cerebral levels of EPO, EPOR and MLTR1 mRNA were increased compared to control. Notably, CHORIO brains at P2 were SIRT1 mRNA deficient with increased HIF1α and HIF2α despite normalized levels of EPO, EPOR and MLTR1, and in the presence of elevated serum EPO levels. Uniquely, brain levels of EPO, EPOR and MLTR1 shifted at P7 and P21, with prominent CHORIO-induced changes in mRNA expression. Reductions at P21 were concomitant with increased serum EPO levels in CHORIO rats compared to controls and variable MLT levels. Discussion: These data reveal that commensurate with robust inflammation through the maternal placental-fetal axis, CHORIO impacts EPO, MLT, SIRT1, and HIF signal transduction defined by dynamic changes in EPO, EPOR, MLTR1, SIRT1, HIF1α and HIF2α mRNA, and EPO protein. Notably, ligand-receptor mismatch, tissue compartment differential regulation, and non-receptor-mediated signaling highlight the importance, complexity and nuance of neural and immune cell development and provide essential clues to mechanisms of injury in PBI. As the placenta, immune cells, and neural cells share many common, developmentally regulated signal transduction pathways, further studies are needed to clarify the perinatal dynamics of EPO and MLT signaling and to capitalize on therapies that target endogenous neurorepair mechanisms.

Beyond brain injury biomarkers: chemoattractants and circulating progenitor cells as biomarkers of endogenous rehabilitation effort in preterm neonates with encephalopathy

Introduction

Preclinical work and studies in adults have shown that endogenous regeneration efforts that involve mobilization of progenitor cells take place after brain injury. However, kinetics of endogenous circulating progenitor cells (CPCs) in preterm neonates is not well described, particularly their possible role regarding brain injury and regeneration. We aimed to assess the kinetics of CPCs in neonates with encephalopathy of prematurity in relation to brain injury biomarkers, chemoattractants and relevant antenatal and postanal clinical factors, in an effort to outline the related pathophysiology.

Materials and methods

47 preterm neonates (of 28-33 weeks GA) were enrolled: 31 newborns with no or minimal brain injury (grade I IVH) and 16 prematures with encephalopathy (grade III or IV IVH, PVL or infarct). Peripheral blood samples obtained on days 1, 3, 9, 18 and 45 after birth were analyzed using flow cytometry, focusing on EPCs (early and late Endothelial Progenitor Cells), HSCs (Hematopoietic Stem Cells) and VSELs (Very Small Embryonic-Like Stem Cells). At the same time-points serum levels of S100B, Neuron-specific Enolase (NSE), Erythropoietin (EPO), Insulin-like growth factor-1 (IGF-1) and SDF-1 were also measured. Neonates were assessed postnatally with brain MRI, and with Bayley III developmental test at 2 years of corrected age.

Results

Preterms with brain injury proved to have significant increase of S100B and NSE, followed by increase of EPO and enhanced mobilization mainly of HSCs, eEPCs and lEPCs. IGF-1 was rather decreased in this group of neonates. IGF-1 and most CPCs were intense decreased in cases of antenatal or postnatal inflammation. S100B and NSE correlated with neuroimaging and language scale in Bayley III test, providing good prognostic ability.

Conclusion

The observed pattern of CPCs' mobilization and its association with neurotrophic factors following preterm brain injury indicate the existence of an endogenous brain regeneration process. Kinetics of different biomarkers and associations with clinical factors contribute to the understanding of the related pathophysiology and might help to early discriminate neonates with adverse outcome. Timely appropriate enhancement of the endogenous regeneration effort, when it is suppressed and insufficient, using neurotrophic factors and exogenous progenitor cells might be a powerful therapeutic strategy in the future to restore brain damage and improve the neurodevelopmental outcome in premature infants with brain injury.

Effect of Early High-Dose Recombinant Human Erythropoietin on Behavior and Quality of Life in Children Aged 5 Years Born Very Preterm: Secondary Analysis of a Randomized Clinical Trial

IMPORTANCE

In light of the promising neuroprotective properties of recombinant human erythropoietin (RHEpo), the Swiss EPO Neuroprotection Trial was started to investigate its effect on neurodevelopment in very preterm infants. The results of the primary and secondary outcome analysis did not show any effect of RHEpo on cognitive performance, neuromotor outcomes, or somatic growth of the study participants at ages 2 or 5 years.

OBJECTIVE

To investigate whether early high-dose RHEpo improves behavioral outcomes and health-related quality of life (HRQoL) at age 5 years.

DESIGN, SETTING, AND PARTICIPANTS

This was a prespecified secondary analysis of the double-blind, placebo-controlled, multicenter Swiss EPO Neuroprotection randomized clinical trial, which was conducted at 5 level-III perinatal centers in Switzerland. Infants born between 26 weeks 0 days' and 31 weeks 6 days' gestation were recruited between 2005 and 2012 and followed-up until age 5 years (last follow-up in 2018). Data were analyzed from January 6 to December 31, 2021.

INTERVENTIONS

Infants were assigned to receive either RHEpo (3000 IU/kg) or placebo (saline, 0.9%) intravenously 3 times within the first 42 hours after birth.

MAIN OUTCOMES AND MEASURES

The prespecified parent-reported measures of behavioral outcomes and health-related quality of life (HRQoL) of their children at the age of 5 years were assessed by two standardized questionnaires: the Strengths and Difficulties Questionnaire (behavioral outcomes) and the KIDSCREEN-27 (HRQoL).

RESULTS

Among 448 randomized infants, 228 infants were assigned to the RHEpo group and 220 infants were assigned to the placebo group. Questionnaire data were available for 317 children (71%) at a mean (SD) age of 5.8 (0.4) years (mean [SD] gestational age at birth, 29.3 [1.6] weeks; mean [SD] birth weight 1220 [340] grams; 128 [40%] female infants). At the age 5 years follow-up, the mean (SD) total difficulties score in the RHEpo group (8.41 [5.60] points) was similar to that of the placebo group (7.76 [4.81]) (P = .37). There were no statistically significant differences between the groups in any other outcome measures.

CONCLUSIONS AND RELEVANCE

This secondary analysis of a randomized clinical trial showed no evidence for an effect of early high-dose RHEpo administration on behavioral outcomes or HRQoL in children born very preterm at early school age.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT00413946.

Neonatal administration of erythropoietin attenuates cognitive deficits in adult rats following placental insufficiency

Preterm birth is a principal cause of neurological disability later in life, including cognitive and behavioral deficits. Notably, cognitive impairment has greater impact on quality of life than physical disability. Survivors of preterm birth commonly have deficits of executive function. Difficulties with tasks and planning complexity correlate positively with increasing disability. To overcome these barriers for children born preterm, preclinical and clinical studies have emphasized the importance of neurorestoration. Erythropoietin (EPO) is a endogenous cytokine with multiple beneficial mechanisms of action following perinatal brain injury. While most preclinical investigations have focused on pathology and molecular mechanisms, translational studies of repair using clinically viable biobehavioral biomarkers are still lacking. Here, using an established model of encephalopathy of prematurity secondary to placental insufficiency, we tested the hypothesis that administration of EPO in the neonatal period would attenuate deficits in recognition memory and cognitive flexibility in adult rats of both sexes. We assessed cognition and executive function in two ways. First, using the classic test of novel object recognition and second, using a touchscreen platform. Touchscreen testing allows for rigorous testing of cognition and executive function in preclinical and clinical scenarios. Data show that adult rats exhibit deficits in recognition memory and cognitive flexibility following in utero placental insufficiency. Notably, neonatal treatment of EPO attenuates these deficits in adulthood and facilitates functional repair. Together, these data validate EPO neurorestoration using a clinically relevant outcome measure and support the concept that postnatal treatment following in utero injury can improve cognition and executive function through adulthood.

Erythropoietin Reduces Death and Neurodevelopmental Impairment in Neonatal Hypoxic-Ischemic Encephalopathy

Purpose: Erythropoietin (EPO) is a promising neuroprotective drug. We investigated whether EPO has beneficial effects on neurodevelopmental outcomes in infants with hypoxic-ischemic encephalopathy (HIE).Methods: We retrospectively reviewed the data of 56 infants with HIE born at or after 35 weeks of gestation who were admitted to Inha University Hospital between 2012 and 2021. Patients were divided into two groups based on EPO use and compared. In the EPO group, patients were administered 1,000 U/kg of EPO on days 1, 2, 3, 5, and 7, starting within 24 hours after birth. The primary outcome was death or neurodevelopmental impairment (NDI) at the age of 12 months.Results: EPO was administered to 38 infants, and 18 did not receive EPO. Only 37.5% of patients with HIE (21/56) and 60% of patients with moderate-to-severe HIE (21/35) received therapeutic hypothermia. Among all patients with HIE, death or NDI (21.1 % vs. 50.0%; odds ratio [OR], 0.09; 95% confidence interval [CI], 0.01 to 0.78; P=0.029) and brain injury on imaging (42.1% vs. 83.3%; OR, 0.16; 95% CI, 0.03 to 0.92; P=0.040) were significantly lower in the EPO group than in the control group. Among patients with moderate-to-severe HIE, brain injury on imaging (54.2% vs. 90.9%; OR, 0.04; 95% CI, 0.002 to 0.700; P=0.027) was significantly lower in the EPO group than in the control group.Conclusion: EPO administration significantly reduced mortality and NDI in infants with HIE. EPO can be considered an adjunctive therapeutic agent for neonatal HIE.

Neonatal subgaleal hemorrhage: twenty years of trends in incidence, associations, and outcomes

BACKGROUND

In 2011, we reported 38 neonates with subgaleal hemorrhage (SH), relating an increasing incidence. It is unclear whether the incidence in our hospitals continued to rise and which risk factors and outcomes are associated with this condition.

DESIGN

We retrospectively analyzed every recognized case of SH in our hospitals from the end of our previous report (2010) to the present (2022). We redescribed the incidence, scored severity, tabulated blood products transfused, and recorded outcomes.

RESULTS

Across 141 months, 191 neonates were diagnosed with SH; 30 after vacuum or forceps. The incidence (one/1815 births) was higher than in our 2011 report (one/7124 births). Also, severe SH (requiring transfusion) was more common (one/10,033 births vs. one/20,950 births previously). Four died (all with severe SH) and 12 had neurodevelopmental impairment.

CONCLUSION

Recognized cases of SH are increasing in our system without a clear explanation. Adverse outcomes are rare but continue to occur.

The Effect of Erythropoietin and Its Derivatives on Ischemic Stroke Therapy: A Comprehensive Review

Numerous studies explored the therapeutic effects of erythropoietin (EPO) on neurodegenerative diseases. Few studies provided comprehensive and latest knowledge of EPO treatment for ischemic stroke. In the present review, we introduced the structure, expression, function of EPO, and its receptors in the central nervous system. Furthermore, we comprehensively discussed EPO treatment in pre-clinical studies, clinical trials, and its therapeutic mechanisms including suppressing inflammation. Finally, advanced studies of the therapy of EPO derivatives in ischemic stroke were also discussed. We wish to provide valuable information on EPO and EPO derivatives’ treatment for ischemic stroke for basic researchers and clinicians to accelerate the process of their clinical applications.

Endogenous erythropoietin at birth is associated with neurodevelopmental morbidity in early childhood

BACKGROUND

New biomarkers that predict later neurodevelopmental morbidity are needed. This study evaluated the associations between umbilical cord serum erythropoietin (us-EPO) and neurodevelopmental morbidity by the age of 2-6.5 years in a Finnish cohort.

METHODS

This study included 878 non-anomalous children born alive in 2012 to 2016 in Helsinki University Hospitals and whose us-EPO concentration was determined at birth. Data of these children were linked to data from the Finnish Medical Birth Register and the Finnish Hospital Discharge Register. Neurodevelopmental morbidity included cerebral palsy, epilepsy, intellectual disability, autism spectrum disorder, sensorineural defects, and minor neurodevelopmental disorders.

RESULTS

In the cohort including both term and preterm children, us-EPO levels correlated with gestational age (r = 0.526) and were lower in premature children. High us-EPO levels (>100 IU/l) were associated with an increased risk of severe neurodevelopmental morbidity (OR: 4.87; 95% CI: 1.05-22.58) when adjusted for the gestational age. The distribution of us-EPO levels did not differ in children with or without the later neurodevelopmental diagnosis.

CONCLUSIONS

Although high us-EPO concentration at birth was associated with an increased risk of neurodevelopmental morbidity in early childhood, the role of us-EPO determination in clinical use appears to be minor.

IMPACT

We determined whether endogenous umbilical cord serum erythropoietin would be a new useful biomarker to predict the risk of neurodevelopmental morbidity. This study evaluated the role of endogenous erythropoietin at birth in neurodevelopmental morbidity with a study population of good size and specific diagnoses based on data from high-quality registers. Although high umbilical cord serum erythropoietin concentration at birth was associated with an increased risk of neurodevelopmental morbidity in early childhood, the clinical value of erythropoietin determination appears to be minor.

Erythropoietin and derivatives: Potential beneficial effects on the brain

Erythropoietin (Epo), the main erythropoiesis-stimulating factor widely prescribed to overcome anemia, is also known nowadays for its cytoprotective action on non-hematopoietic tissues. In this context, Epo showed not only its ability to cross the blood-brain barrier, but also its expression in the brain of mammals. In clinical trials, recombinant Epo treatment has been shown to stimulate neurogenesis; improve cognition; and activate antiapoptotic, antioxidant, and anti-inflammatory signaling pathways. These mechanisms, proposed to characterize a neuroprotective property, opened new perspectives on the Epo pharmacological potencies. However, many questions arise about a possible physiological role of Epo in the central nervous system (CNS) and the factors or environmental conditions that induce its expression. Although Epo may be considered a strong candidate to be used against neuronal damage, long-term treatments, particularly when high Epo doses are needed, may induce thromboembolic complications associated with increases in hematocrit and blood viscosity. To avoid these adverse effects, different Epo analogs without erythropoietic activity but maintaining neuroprotection ability are currently being investigated. Carbamylated erythropoietin, as well as alternative molecules like Epo fusion proteins and partial peptides of Epo, seems to match this profile. This review will focus on the discussion of experimental evidence reported in recent years linking erythropoietin and CNS function through investigations aimed at finding benefits in the treatment of neurodegenerative diseases. In addition, it will review the proposed mechanisms for novel derivatives which may clarify and, eventually, improve the neuroprotective action of Epo.

Utilization of Erythropoietin within the United States Neonatal Intensive Care Units from 2008 to 2017

OBJECTIVE

Little data are available regarding erythropoietin (Epo) utilization patterns within neonatal intensive care units (NICUs). We sought to describe the trends in Epo utilization across a large cohort of U.S. NICUs.

STUDY DESIGN

This is a retrospective cohort study of infants discharged from 2008 to 2017 using the Pediatrix Clinical Data Warehouse.

RESULTS

We identified 704,159 eligible infants from 358 sites, of whom 9,749 (1.4%) had Epo exposure. For extremely low gestational age newborns (ELGANs), Epo exposure ranged from 7.6 to 13.5%. We found significant site variability in Epo utilization in ELGANs. Among the 299 NICUs caring for ELGANs during the study period, 184 (61.5%) never used Epo for this population, whereas 21 (7%) utilized Epo in 50% or more of eligible infants. Epo was initiated at a median of 25 days in ELGANs. For infants with hypoxic-ischemic encephalopathy (HIE), Epo exposure remained ≤1% through 2014 then increased fourfold to 3.4% by 2017. The median day of Epo initiation was the day of birth for infants diagnosed with HIE.

CONCLUSION

Epo is utilized in ELGANs more commonly than for other NICU populations. Utilization patterns appear to indicate the treatment of established anemia for ELGANs and more recently for neuroprotection in patients diagnosed with HIE.

Effect of blood transfusions on cognitive development in very low birth weight infants

OBJECTIVE

Preterm infants frequently receive red cell transfusions; however, the effect of transfusions on cognition is unclear. We evaluated the relationship between transfusions and cognitive outcomes in preterm infants enrolled in a randomized trial of erythropoiesis stimulating agents (ESAs).

STUDY DESIGN

Preterm infants were randomized to ESAs or placebo during initial hospitalization, and transfusions recorded. Children were evaluated using standard developmental tests of cognition at 18-22 months (56 ESA, 24 placebo) and 3.5-4 years (39 ESA, 14 placebo).

RESULTS

Cognitive scores at 18-22 months were inversely correlated with transfusion volume (p = 0.02). Among those receiving ≥1 transfusion, cognitive scores were significantly higher in the ESA-treated group (p = 0.003). At 3.5-4 years, transfusions were not correlated with cognitive scores.

CONCLUSIONS

In the placebo group, transfused children had lower cognitive scores than did non-transfused children at 18-22 months. In the ESA group, cognitive scores did not differ by transfusion status, suggesting ESAs might provide neuroprotection.

Whether erythropoietin can be a neuroprotective agent against premature brain injury: cellular mechanisms and clinical efficacy

Preterm infants are at high risk of brain injury. With more understanding of the preterm brain injury's pathogenesis, neuroscientists are looking for more effective methods to prevent and treat it, among which erythropoietin (Epo) is considered as a prime candidate. This review tries to clarify the possible mechanisms of Epo in preterm neuroprotection and summarize updated evidence considering Epo as a pharmacological neuroprotective strategy in animal models and clinical trials. To date, various animal models have validated that Epo is an anti-apoptotic, anti-inflammatory, anti-oxidant, anti-excitotoxic, neurogenetic, erythropoietic, angiogenetic, and neurotrophic agent, thus preventing preterm brain injury. However, although the scientific rationale and preclinical data for Epo's neuroprotective effect are promising, when translated to bedside, the results vary in different studies, especially in its long-term efficacy. Based on existing evidence, it is still too early to recommend Epo as the standard treatment for preterm brain injury.

Iron stores at birth in a full-term normal birth weight birth cohort with a low level of inflammation

Iron stores at birth are essential to meet iron needs during the first 4-6 months of life. The present study aimed to investigate iron stores in normal birth weight, healthy, term neonates. Umbilical cord blood samples were collected from apparently normal singleton vaginal deliveries (n=854). Subjects were screened and excluded if C-reactive protein (CRP) > 5 mg/l or α1-acid glycoprotein (AGP) > 1 g/l, preterm (<37 complete weeks), term < 2500g or term > 4000g. In total, 762 samples were included in the study. Serum ferritin, soluble transferrin receptor (sTfR), hepcidin, and erythropoietin (EPO) were measured in umbilical cord blood samples; total body iron (TBI) (mg/kg) was calculated using sTfR and ferritin concentrations. A total of 19.8% newborns were iron deficient (ferritin 35 μg/l) and an additional 46.6% had insufficient iron stores (ferritin < 76 μg/l). There was a positive association between serum ferritin and sTfR, hepcidin, and EPO. Gestational age was positively associated with ferritin, sTfR, EPO, and hepcidin. In conclusion, we demonstrate a high prevalence of insufficient iron stores in a Chinese birth cohort. The value of cord sTfR and TBI in the assessment of iron status in the newborn is questionable, and reference ranges need to be established.

Iron Nutrition, Erythrocytes, and Erythropoietin in the NICU: Erythropoietic and Neuroprotective Effects

Prematurity, maternal diabetes, maternal smoking, being medically underserved, and small size for gestational age are common characteristics of neonates in the NICU and can predispose them to develop congenital iron deficiency. Iron is critical for organ development. In the fetus and newborn, iron is prioritized for red blood cell production, sometimes at the expense of other tissues, including the brain. It is critical to optimize iron levels in newborns to support erythropoiesis, growth, and brain development. Available studies support improved neurodevelopmental outcomes with either iron supplementation or delayed umbilical cord clamping at birth. Erythropoietic doses of erythropoietin/erythrocyte-stimulating agents may also improve neurocognitive outcomes. However, the literature on the effect of liberal red blood cell transfusions on long-term neurodevelopment is mixed. Understanding age-specific normal values and monitoring of iron indices can help individualize and optimize the iron status of patients in the NICU.

Erythropoietin Improves Poor Outcomes in Preterm Infants with Intraventricular Hemorrhage

BACKGROUND

Intraventricular hemorrhage (IVH) is a common complication in preterm infants that has poor outcomes, especially in severe cases, and there are currently no widely accepted effective treatments. Erythropoietin has been shown to be neuroprotective in neonatal brain injury.

OBJECTIVE

The objective of this study was to evaluate the protective effect of repeated low-dose recombinant human erythropoietin (rhEPO) in preterm infants with IVH.

METHODS

This was a single-blinded prospective randomized controlled trial. Preterm infants ≤ 32 weeks gestational age who were diagnosed with IVH within 72 h after birth were randomized to receive rhEPO 500 IU/kg or placebo (equivalent volume of saline) every other day for 2 weeks. The primary outcome was death or neurological disability assessed at 18 months of corrected age.

RESULTS

A total of 316 eligible infants were included in the study, with 157 in the rhEPO group and 159 in the placebo group. Although no significant differences in mortality (p = 0.176) or incidence of neurological disability (p = 0.055) separately at 18 months of corrected age were seen between the rhEPO and placebo groups, significantly fewer infants had poor outcomes (death and neurological disability) in the rhEPO group: 14.9 vs. 26.4%; odds ratio (OR) 0.398; 95% confidence interval (CI) 0.199-0.796; p = 0.009. In addition, the incidence of Mental Development Index scores of < 70 was lower in the rhEPO group than in the placebo group: 7.2 vs. 15.3%; OR 0.326; 95% CI 0.122-0.875; p = 0.026.

CONCLUSIONS

Treatment with repeated low-dose rhEPO improved outcomes in preterm infants with IVH.

TRIAL REGISTRATION

The study was retrospectively registered on ClinicalTrials.gov on 16 April 2019 (NCT03914690).

Prophylactic Erythropoietin for Neuroprotection in Very Preterm Infants: A Meta-Analysis Update

A meta-analysis update of randomized controlled trials investigating recombinant human erythropoietin suggests improved neurodevelopmental outcome in preterm infants. There was substantial heterogeneity, which could be ascribed to a single trial. Exclusion of this trial featuring a high risk of bias abolished heterogeneity and any effects of recombinant human erythropoietin treatment.

Neurodevelopmental Outcomes at Age 5 Years After Prophylactic Early High-Dose Recombinant Human Erythropoietin for Neuroprotection in Very Preterm Infants

This study reports 5-year neurodevelopmental outcomes for Swiss children born before 32 weeks’ gestation and randomized at birth to receive early high-dose recombinant human erythropoietin (rhEpo) vs placebo.

High-Dose Erythropoietin in Extremely Low Gestational Age Neonates Does Not Alter Risk of Retinopathy of Prematurity

INTRODUCTION

The Preterm Erythropoietin (Epo) Neuroprotection (PENUT) Trial sought to determine the safety and efficacy of early high-dose Epo as a potential neuroprotective treatment. We hypothesized that Epo would not increase the incidence or severity of retinopathy of prematurity (ROP).

METHODS

A total of 941 infants born between 24-0/7 and 27-6/7 weeks' gestation were randomized to 1,000 U/kg Epo or placebo intravenously for 6 doses, followed by subcutaneous or sham injections of 400 U/kg Epo 3 times a week through 32 weeks post-menstrual age. In this secondary analysis of PENUT trial data, survivors were evaluated for ROP. A modified intention-to-treat approach was used to compare treatment groups. In addition, risk factors for ROP were evaluated using regression methods that account for multiples and allow for adjustment for treatment and gestational age at birth.

RESULTS

Of 845 subjects who underwent ROP examination, 503 were diagnosed with ROP with similar incidence and severity between treatment groups. Gestational age at birth, birth weight, prenatal magnesium sulfate, maternal antibiotic exposure, and presence of heart murmur at 2 weeks predicted the development of any ROP, while being on high-frequency oscillator or high-frequency jet ventilation (HFOV/HFJV) at 2 weeks predicted severe ROP.

CONCLUSION

Early high-dose Epo followed by maintenance dosing through 32 weeks does not increase the risk of any or severe ROP in extremely low gestational age neonates. Gestational age, birth weight, maternal treatment with magnesium sulfate, antibiotic use during pregnancy, and presence of a heart murmur at 2 weeks were associated with increased risk of any ROP. Treatment with HFOV/HFJV was associated with an increased risk of severe ROP.

Erythropoietin Improves Atrophy, Bleeding and Cognition in the Newborn Intraventricular Hemorrhage

The germinal matrix-intraventricular hemorrhage (GM-IVH) is one of the most devastating complications of prematurity. The short- and long-term neurodevelopmental consequences after severe GM-IVH are a major concern for neonatologists. These kids are at high risk of psychomotor alterations and cerebral palsy; however, therapeutic approaches are limited. Erythropoietin (EPO) has been previously used to treat several central nervous system complications due to its role in angiogenesis, neurogenesis and as growth factor. In addition, EPO is regularly used to reduce the number of transfusions in the preterm infant. Moreover, EPO crosses the blood-brain barrier and EPO receptors are expressed in the human brain throughout development. To analyze the role of EPO in the GM-IVH, we have administered intraventricular collagenase (Col) to P7 mice, as a model of GM-IVH of the preterm infant. After EPO treatment, we have characterized our animals in the short (14 days) and the long (70 days) term. In our hands, EPO treatment significantly limited brain atrophy and ventricle enlargement. EPO also restored neuronal density and ameliorated dendritic spine loss. Likewise, inflammation and small vessel bleeding were also reduced, resulting in the preservation of learning and memory abilities. Moreover, plasma gelsolin levels, as a feasible peripheral marker of GM-IVH-induced damage, recovered after EPO treatment. Altogether, our data support the positive effect of EPO treatment in our preclinical model of GM-IVH, both in the short and the long term.

Update on Erythropoiesis-Stimulating Agents Administered to Neonates for Neuroprotection

Erythropoiesis-stimulating agents (ESAs) such as erythropoietin and darbepoetin have been studied as red blood cell growth factors in preterm and term infants for more than 30 years. Recently, studies have focused on the potential neuroprotective effects of ESAs. In this review, we summarize preclinical animal models and recent clinical trials that provide evidence for ESAs as potential treatments to improve neurodevelopmental outcomes in preterm and term infants.

Repetitive Erythropoietin Treatment Improves Long-Term Neurocognitive Outcome by Attenuating Hyperoxia-Induced Hypomyelination in the Developing Brain

Introduction: Preterm infants born before 28 weeks of gestation are at high risk of neurodevelopmental impairment in later life. Cerebral white and gray matter injury is associated with adverse outcomes. High oxygen levels, often unavoidable in neonatal intensive care, have been identified as one of the main contributing factors to preterm brain injury. Thus, preventive and therapeutic strategies against hyperoxia-induced brain injury are needed. Erythropoietin (Epo) is a promising and also neuroprotective candidate due to its clinical use in infants as erythropoiesis-stimulating agent. Objective: The objective of this study was to investigate the effects of repetitive Epo treatment on the cerebral white matter and long-term motor-cognitive outcome in a neonatal rodent model of hyperoxia-induced brain injury. Methods: Three-day old Wistar rats were exposed to hyperoxia (48 h, 80% oxygen). Four doses of Epo (5,000 IU/kg body weight per day) were applied intraperitoneally from P3-P6 with the first dose at the onset of hyperoxia. Oligodendrocyte maturation and myelination were evaluated via immunohistochemistry and Western blot on P11. Motor-cognitive deficits were assessed in a battery of complex behavior tests (Open Field, Novel Object Recognition, Barnes maze) in adolescent and fully adult animals. Following behavior tests animals underwent post-mortem diffusion tensor imaging to investigate long-lasting microstructural alterations of the white matter. Results: Repetitive treatment with Epo significantly improved myelination deficits following neonatal hyperoxia at P11. Behavioral testing revealed attenuated hyperoxia-induced cognitive deficits in Epo-treated adolescent and adult rats. Conclusion: A multiple Epo dosage regimen protects the developing brain against hyperoxia-induced brain injury by improving myelination and long-term cognitive outcome. Though current clinical studies on short-term outcome of Epo-treated prematurely born children contradict our findings, long-term effects up to adulthood are still lacking. Our data support the essential need for long-term follow-up of preterm infants in current clinical trials.

Early erythropoiesis-stimulating agents in preterm or low birth weight infants

BACKGROUND

Preterm infants have low plasma levels of erythropoietin (EPO), providing a rationale for the use of erythropoiesis-stimulating agents (ESAs) to prevent or treat anaemia and to provide neuro protection and protection against necrotising enterocolitis (NEC). Darbepoetin (Darbe) and EPO are currently available ESAs.

OBJECTIVES

To assess the effectiveness and safety of ESAs (erythropoietin (EPO) and/or Darbe) initiated early (before eight days after birth) compared with placebo or no intervention in reducing red blood cell (RBC) transfusions, adverse neurological outcomes, and feeding intolerance including necrotising enterocolitis (NEC) in preterm and/or low birth weight infants. Primary objective for studies that primarily investigate the effectiveness and safety of ESAs administered early in reducing red blood cell transfusions: To assess the effectiveness and safety of ESAs initiated early in reducing red blood cell transfusions in preterm infants. Secondary objectives: Review authors performed subgroup analyses of low (≤ 500 IU/kg/week) and high (> 500 IU/kg/week) doses of EPO and the amount of iron supplementation provided: none, low (≤ 5 mg/kg/d), and high (> 5 mg/kg/d). Primary objective for studies that primarily investigate the neuro protective effectiveness of ESAs: To assess the effectiveness and safety of ESAs initiated early in reducing adverse neurological outcomes in preterm infants. Primary objective for studies that primarily investigate the effectiveness of EPO or Darbe administered early in reducing feeding intolerance: To assess the effectiveness and safety of ESAs administered early in reducing feeding intolerance (and NEC) in preterm infants. Other secondary objectives: To compare the effectiveness of ESAs in reducing the incidence of adverse events and improving long-term neurodevelopmental outcomes.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 2), MEDLINE via PubMed (1966 to 10 March 2017), Embase (1980 to 10 March 2017), and the Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982 to 10 March 2017). We searched clinical trials databases, conference proceedings, and reference lists of retrieved articles for randomised and quasi-randomised controlled trials.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials of early initiation of EAS treatment versus placebo or no intervention in preterm or low birth weight infants.

DATA COLLECTION AND ANALYSIS

We used the methods described in the Cochrane Handbook for Systematic Reviews of Interventions and the GRADE approach to assess the quality of evidence.

MAIN RESULTS

This updated review includes 34 studies enrolling 3643 infants. All analyses compared ESAs versus a control consisting of placebo or no treatment. Early ESAs reduced the risk of 'use of one or more [red blood cell] RBC transfusions' (typical risk ratio (RR) 0.79, 95% confidence interval (CI) 0.74 to 0.85; typical risk difference (RD) -0.14, 95% CI -0.18 to -0.10; I2 = 69% for RR and 62% for RD (moderate heterogeneity); number needed to treat for an additional beneficial outcome (NNTB) 7, 95% CI 6 to 10; 19 studies, 1750 infants). The quality of the evidence was low. Necrotising enterocolitis was significantly reduced in the ESA group compared with the placebo group (typical RR 0.69, 95% CI 0.52 to 0.91; typical RD -0.03, 95% CI -0.05 to -0.01; I2 = 0% for RR and 22% for RD (low heterogeneity); NNTB 33, 95% CI 20 to 100; 15 studies, 2639 infants). The quality of the evidence was moderate. Data show a reduction in 'Any neurodevelopmental impairment at 18 to 22 months' corrected age in the ESA group (typical RR 0.62, 95% CI 0.48 to 0.80; typical RD -0.08, 95% CI -0.12 to -0.04; NNTB 13, 95% CI 8 to 25. I2 = 76% for RR (high heterogeneity) and 66% for RD (moderate); 4 studies, 1130 infants). The quality of the evidence was low. Results reveal increased scores on the Bayley-II Mental Development Index (MDI) at 18 to 24 months in the ESA group (weighted mean difference (WMD) 8.22, 95% CI 6.52 to 9.92; I2 = 97% (high heterogeneity); 3 studies, 981 children). The quality of the evidence was low. The total volume of RBCs transfused per infant was reduced by 7 mL/kg. The number of RBC transfusions per infant was minimally reduced, but the number of donors to whom infants who were transfused were exposed was not significantly reduced. Data show no significant difference in risk of stage ≥ 3 retinopathy of prematurity (ROP) with early EPO (typical RR 1.24, 95% CI 0.81 to 1.90; typical RD 0.01, 95% CI -0.02 to 0.04; I2 = 0% (no heterogeneity) for RR; I2 = 34% (low heterogeneity) for RD; 8 studies, 1283 infants). Mortality was not affected, but results show significant reductions in the incidence of intraventricular haemorrhage (IVH) and periventricular leukomalacia (PVL).

AUTHORS' CONCLUSIONS

Early administration of ESAs reduces the use of red blood cell (RBC) transfusions, the volume of RBCs transfused, and donor exposure after study entry. Small reductions are likely to be of limited clinical importance. Donor exposure probably is not avoided, given that all but one study included infants who had received RBC transfusions before trial entry. This update found no significant difference in the rate of ROP (stage ≥ 3) for studies that initiated EPO treatment at less than eight days of age, which has been a topic of concern in earlier versions of this review. Early EPO treatment significantly decreased rates of IVH, PVL, and NEC. Neurodevelopmental outcomes at 18 to 22 months and later varied in published studies. Ongoing research should evaluate current clinical practices that will limit donor exposure. Promising but conflicting results related to the neuro protective effect of early EPO require further study. Very different results from the two largest published trials and high heterogeneity in the analyses indicate that we should wait for the results of two ongoing large trials before drawing firm conclusions. Administration of EPO is not currently recommended because limited benefits have been identified to date. Use of darbepoetin requires further study.

Unisensory and Multisensory Responses in Fetal Alcohol Spectrum Disorders (FASD): Effects of Spatial Congruence

While it is generally accepted that structural and functional brain deficits underlie the behavioral deficits associated with Fetal Alcohol Spectrum Disorders (FASD), the degree to which these problems are expressed in sensory pathology is unknown. Electrophysiological measures indicate that neural processing is delayed in visual and auditory domains. Furthermore, multiple reports of white matter deficits due to prenatal alcohol exposure indicate altered cortical connectivity in individuals with FASD. Multisensory integration requires close coordination between disparate cortical areas leading us to hypothesize that individuals with FASD will have impaired multisensory integration relative to healthy control (HC) participants. Participants' neurophysiological responses were recorded using magnetoencephalography (MEG) during passive unisensory or simultaneous, spatially congruent or incongruent multisensory auditory and somatosensory stimuli. Source timecourses from evoked responses were estimated using multi-dipole spatiotemporal modeling. Auditory M100 response latency was faster for the multisensory relative to the unisensory condition but no group differences were observed. M200 auditory latency to congruent stimuli was earlier and congruent amplitude was larger in participants with FASD relative to controls. Somatosensory M100 response latency was faster in right hemisphere for multisensory relative to unisensory stimulation in both groups. FASD participants' somatosensory M200 responses were delayed by 13 ms, but only for the unisensory presentation of the somatosensory stimulus. M200 results indicate that unisensory and multisensory processing is altered in FASD; it remains to be seen if the multisensory response represents a normalization of the unisensory deficits.

Dysmaturation of Premature Brain: Importance, Cellular Mechanisms, and Potential Interventions

Prematurity, especially preterm birth (less than 32 weeks' gestation), is common and associated with high rates of both survival and neurodevelopmental disability, especially apparent in cognitive spheres. The neuropathological substrate of this disability is now recognized to be related to a variety of dysmaturational disturbances of the brain. These disturbances follow initial brain injury, particularly cerebral white matter injury, and involve many of the extraordinary array of developmental events active in cerebral white and gray matter structures during the premature period. This review delineates these developmental events and the dysmaturational disturbances that occur in premature infants. The cellular mechanisms involved in the genesis of the dysmaturation are emphasized, with particular focus on the preoligodendrocyte. A central role for the diffusely distributed activated microglia and reactive astrocytes in the dysmaturation is now apparent. As these dysmaturational cellular mechanisms appear to occur over a relatively long time window, interventions to prevent or ameliorate the dysmaturation, that is, neurorestorative interventions, seem possible. Such interventions include pharmacologic agents, especially erythropoietin, and particular attention has also been paid to such nutritional factors as quality and source of milk, breastfeeding, polyunsaturated fatty acids, iron, and zinc. Recent studies also suggest a potent role for interventions directed at various experiential factors in the neonatal period and infancy, i.e., provision of optimal auditory and visual exposures, minimization of pain and stress, and a variety of other means of environmental behavioral enrichment, in enhancing brain development.

Time to reconsider extended erythropoietin treatment for infantile traumatic brain injury?

Pediatric traumatic brain injury (TBI) remains a leading cause of childhood morbidity and mortality worldwide. Most efforts to reduce the chronic impact of pediatric TBI involve prevention and minimization of secondary injury. Currently, no treatments are used in routine clinical care during the acute and subacute phases to actively repair injury to the developing brain. The endogenous pluripotent cytokine erythropoietin (EPO) holds promise as an emerging neuroreparative agent in perinatal brain injury (PBI). EPO signaling in the central nervous system (CNS) is essential for multiple stages of neurodevelopment, including the genesis, survival and differentiation of multiple lineages of neural cells. Postnatally, EPO signaling decreases markedly as the CNS matures. Importantly, high-dose, extended EPO regimens have shown efficacy in preclinical controlled cortical impact (CCI) models of infant TBI at two different, early ages by independent research groups. Specifically, extended high-dose EPO treatment after infantile CCI prevents long-term cognitive deficits in adult rats. Because of the striking differences in the molecular and cellular responses to both injury and recovery in the developing and mature CNS, and the excellent safety profile of EPO in infants and children, extended courses of EPO are currently in Phase III trials for neonates with PBI. Extended, high-dose EPO may also warrant testing for infants and young children with TBI.

Extended Combined Neonatal Treatment With Erythropoietin Plus Melatonin Prevents Posthemorrhagic Hydrocephalus of Prematurity in Rats

Posthemorrhagic hydrocephalus of prematurity (PHHP) remains a global challenge. Early preterm infants (<32 weeks gestation), particularly those exposed to chorioamnionitis (CAM), are prone to intraventricular hemorrhage (IVH) and PHHP. We established an age-appropriate, preclinical model of PHHP with progressive macrocephaly and ventriculomegaly to test whether non-surgical neonatal treatment could modulate PHHP. We combined prenatal CAM and postnatal day 1 (P1, equivalent to 30 weeks human gestation) IVH in rats, and administered systemic erythropoietin (EPO) plus melatonin (MLT), or vehicle, from P2 to P10. CAM-IVH rats developed progressive macrocephaly through P21. Macrocephaly was accompanied by ventriculomegaly at P5 (histology), and P21 (ex vivo MRI). CAM-IVH rats showed impaired performance of cliff aversion, a neonatal neurodevelopmental test. Neonatal EPO+MLT treatment prevented macrocephaly and cliff aversion impairment, and significantly reduced ventriculomegaly. EPO+MLT treatment prevented matted or missing ependymal motile cilia observed in vehicle-treated CAM-IVH rats. EPO+MLT treatment also normalized ependymal yes-associated protein (YAP) mRNA levels, and reduced ependymal GFAP-immunolabeling. Vehicle-treated CAM-IVH rats exhibited loss of microstructural integrity on diffusion tensor imaging, which was normalized in EPO+MLT-treated CAM-IVH rats. In summary, combined prenatal systemic inflammation plus early postnatal IVH caused progressive macrocephaly, ventriculomegaly and delayed development of cliff aversion reminiscent of PHHP. Neonatal systemic EPO+MLT treatment prevented multiple hallmarks of PHHP, consistent with a clinically viable, non-surgical treatment strategy.

Extended Erythropoietin Treatment Prevents Chronic Executive Functional and Microstructural Deficits Following Early Severe Traumatic Brain Injury in Rats

Survivors of infant traumatic brain injury (TBI) are prone to chronic neurological deficits that impose lifelong individual and societal burdens. Translation of novel interventions to clinical trials is hampered in part by the lack of truly representative preclinical tests of cognition and corresponding biomarkers of functional outcomes. To address this gap, the ability of a high-dose, extended, post-injury regimen of erythropoietin (EPO, 3000U/kg/dose × 6d) to prevent chronic cognitive and imaging deficits was tested in a postnatal day 12 (P12) controlled-cortical impact (CCI) model in rats, using touchscreen operant chambers and regional analysis of diffusion tensor imaging (DTI). Results indicate that EPO prevents functional injury and MRI injury after infant TBI. Specifically, subacute DTI at P30 revealed widespread microstructural damage that is prevented by EPO. Assessment of visual discrimination on a touchscreen operant chamber platform demonstrated that all groups can perform visual discrimination. However, CCI rats treated with vehicle failed to pass reversal learning, and perseverated, in contrast to sham and CCI-EPO rats. Chronic DTI at P90 showed EPO treatment prevented contralateral white matter and ipsilateral lateral prefrontal cortex damage. This DTI improvement correlated with cognitive performance. Taken together, extended EPO treatment restores executive function and prevents microstructural brain abnormalities in adult rats with cognitive deficits in a translational preclinical model of infant TBI. Sophisticated testing with touchscreen operant chambers and regional DTI analyses may expedite translation and effective yield of interventions from preclinical studies to clinical trials. Collectively, these data support the use of EPO in clinical trials for human infants with TBI.

Chorioamnionitis, neuroinflammation, and injury: timing is key in the preterm ovine fetus

Background

Antenatal infection (i.e., chorioamnionitis) is an important risk factor for adverse neurodevelopmental outcomes after preterm birth. Destructive and developmental disturbances of the white matter are hallmarks of preterm brain injury. Understanding the temporal effects of antenatal infection in relation to the onset of neurological injury is crucial for the development of neurotherapeutics for preterm infants. However, these dynamics remain unstudied.

Methods

Time-mated ewes were intra-amniotically injected with lipopolysaccharide at 5, 12, or 24 h or 2, 4, 8, or 15 days before preterm delivery at 125 days gestational age (term ~ 150 days). Post mortem analyses for peripheral immune activation, neuroinflammation, and white matter/neuronal injury were performed. Moreover, considering the neuroprotective potential of erythropoietin (EPO) for perinatal brain injury, we evaluated (phosphorylated) EPO receptor (pEPOR) expression in the fetal brain following LPS exposure.

Results

Intra-amniotic exposure to this single bolus of LPS resulted in a biphasic systemic IL-6 and IL-8 response. In the developing brain, intra-amniotic LPS exposure induces a persistent microgliosis (IBA-1 immunoreactivity) but a shorter-lived increase in the pro-inflammatory marker COX-2. Cell death (caspase-3 immunoreactivity) was only observed when LPS exposure was greater than 8 days in the white matter, and there was a reduction in the number of (pre) oligodendrocytes (Olig2- and PDGFRα-positive cells) within the white matter at 15 days post LPS exposure only. pEPOR expression displayed a striking biphasic regulation following LPS exposure which may help explain contradicting results among clinical trials that tested EPO for the prevention of preterm brain injury.

Conclusion

We provide increased understanding of the spatiotemporal pathophysiological changes in the preterm brain following intra-amniotic inflammation which may aid development of new interventions or implement interventions more effectively to prevent perinatal brain damage.

The long-term effect of erythropoiesis stimulating agents given to preterm infants: a proton magnetic resonance spectroscopy study on neurometabolites in early childhood

BACKGROUND

Erythropoiesis stimulating agents (ESAs) are neuroprotective in cell and animal models of preterm birth. Prematurity has been shown to alter neurometabolite levels in children in studies using proton magnetic resonance spectroscopy (1H-MRS).

OBJECTIVE

We hypothesized that ESA treatment in premature infants would tend to normalize neurometabolites by 4-6 years of age.

MATERIALS AND METHODS

Children in a longitudinal study of neurodevelopment underwent MRI and 1H-MRS at approximately 4 years and 6 years of age. Prematurely born children (500-1,250 g birth weight) received ESAs (erythropoietin or darbepoetin) or placebo during their neonatal hospitalization, and these groups were compared to healthy term controls. 1H-MRS spectra were obtained from the anterior cingulate (gray matter) and frontal lobe white matter, assessing combined N-acetylaspartate and N-acetylaspartylglutamate (tNAA), myo-inositol, choline compounds (Cho), combined creatine and phosphocreatine, and combined glutamate and glutamine.

RESULTS

No significant (P≤0.5) group differences were observed for any metabolite level. Significant age-related increases in white-matter tNAA and Cho were observed, as well as a trend for increased gray-matter tNAA.

CONCLUSION

Neither prematurity nor neonatal ESA treatment was associated with differences in brain metabolite levels in the children of this study at a significance level of 0.05. These findings suggest that earlier differences that might have existed had normalized by 4-6 years of age or were too small to be statistically significant in the current sample.

Darbepoetin Alfa in Young Infants With Renal Failure: Single Center Experience, a Case Series and Review of the Literature

Background: Anemia treatment in infants with advanced or chronic kidney disease (CKD) represents an important challenge to nephrologists. The use of darbepoetin alfa, a novel erythropoiesis stimulating agent, has largely replaced recombinant human erythropoietin in older children and in adults with CKD. However, studies reporting the use of darbepoetin alfa in infants below 1 year of age are rare. Case presentation: We report the data of three infants with advanced stage kidney failure, aged 1, 4, and 7 months, who were treated with darbepoetin alfa and followed for 18-41 months. Hemoglobin levels increased in all three patients, reaching the target levels of 10.7-12 g/dl by 11, 19, and 22 weeks respectively, without any documented adverse effects. Patients younger than 1 year of age required a larger darbepoetin alfa dosage (ranged from 1.2 to 2.9 μg/kg per month) as compared to older children. A review of the literature found only three studies using darbepoetin alfa successfully in such young infants, with similar dosage and clinical success. Conclusion: In these three patients with advanced kidney disease, darbepoetin alfa was effective in correcting anemia with no observed side effects. It reinforces its potential use in very young patients with advanced CKD.

Neonatal erythropoietin mitigates impaired gait, social interaction and diffusion tensor imaging abnormalities in a rat model of prenatal brain injury

Children who are born preterm are at risk for encephalopathy of prematurity, a leading cause of cerebral palsy, cognitive delay and behavioral disorders. Current interventions are limited and none have been shown to reverse cognitive and behavioral impairments, a primary determinant of poor quality of life for these children. Moreover, the mechanisms of perinatal brain injury that result in functional deficits and imaging abnormalities in the mature brain are poorly defined, limiting the potential to target interventions to those who may benefit most. To determine whether impairments are reversible after a prenatal insult, we investigated a spectrum of functional deficits and diffusion tensor imaging (DTI) abnormalities in young adult animals. We hypothesized that prenatal transient systemic hypoxia-ischemia (TSHI) would induce multiple functional deficits concomitant with reduced microstructural white and gray matter integrity, and tested whether these abnormalities could be ameliorated using postnatal erythropoietin (EPO), an emerging neurorestorative intervention. On embryonic day 18 uterine arteries were transiently occluded for 60min via laparotomy. Shams underwent anesthesia and laparotomy for 60min. Pups were born and TSHI pups were randomized to receive EPO or vehicle via intraperitoneal injection on postnatal days 1 to 5. Gait, social interaction, olfaction and open field testing was performed from postnatal day 25-35 before brains underwent ex vivo DTI to measure fractional anisotropy, axial diffusivity and radial diffusivity. Prenatal TSHI injury causes hyperactivity, impaired gait and poor social interaction in young adult rats that mimic the spectrum of deficits observed in children born preterm. Collectively, these data show for the first time in a model of encephalopathy of prematurity that postnatal EPO treatment mitigates impairments in social interaction, in addition to gait deficits. EPO also normalizes TSHI-induced microstructural abnormalities in fractional anisotropy and radial diffusivity in multiple regions, consistent with improved structural integrity and recovery of myelination. Taken together, these results show behavioral and memory deficits from perinatal brain injury are reversible. Furthermore, resolution of DTI abnormalities may predict responsiveness to emerging interventions, and serve as a biomarker of CNS injury and recovery.

Early erythropoiesis-stimulating agents in preterm or low birth weight infants

BACKGROUND

Preterm infants have low plasma levels of erythropoietin (EPO), providing a rationale for the use of erythropoiesis-stimulating agents (ESAs) to prevent or treat anaemia and to provide neuro protection and protection against necrotising enterocolitis (NEC). Darbepoetin (Darbe) and EPO are currently available ESAs.

OBJECTIVES

To assess the effectiveness and safety of ESAs (erythropoietin (EPO) and/or Darbe) initiated early (before eight days after birth) compared with placebo or no intervention in reducing red blood cell (RBC) transfusions, adverse neurological outcomes, and feeding intolerance including necrotising enterocolitis (NEC) in preterm and/or low birth weight infants. Primary objective for studies that primarily investigate the effectiveness and safety of ESAs administered early in reducing red blood cell transfusions:To assess the effectiveness and safety of ESAs initiated early in reducing red blood cell transfusions in preterm infants. Secondary objectives:Review authors performed subgroup analyses of low (≤ 500 IU/kg/week) and high (> 500 IU/kg/week) doses of EPO and the amount of iron supplementation provided: none, low (≤ 5 mg/kg/d), and high (> 5 mg/kg/d). Primary objective for studies that primarily investigate the neuro protective effectiveness of ESAs:To assess the effectiveness and safety of ESAs initiated early in reducing adverse neurological outcomes in preterm infants. Primary objective for studies that primarily investigate the effectiveness of EPO or Darbe administered early in reducing feeding intolerance:To assess the effectiveness and safety of ESAs administered early in reducing feeding intolerance (and NEC) in preterm infants. Other secondary objectives:To compare the effectiveness of ESAs in reducing the incidence of adverse events and improving long-term neurodevelopmental outcomes.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 2), MEDLINE via PubMed (1966 to 10 March 2017), Embase (1980 to 10 March 2017), and the Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982 to 10 March 2017). We searched clinical trials databases, conference proceedings, and reference lists of retrieved articles for randomised and quasi-randomised controlled trials.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials of early initiation of EAS treatment versus placebo or no intervention in preterm or low birth weight infants.

DATA COLLECTION AND ANALYSIS

We used the methods described in the Cochrane Handbook for Systematic Reviews of Interventions and the GRADE approach to assess the quality of evidence.

MAIN RESULTS

This updated review includes 34 studies enrolling 3643 infants. All analyses compared ESAs versus a control consisting of placebo or no treatment.Early ESAs reduced the risk of 'use of one or more [red blood cell] RBC transfusions' (typical risk ratio (RR) 0.79, 95% confidence interval (CI) 0.74 to 0.85; typical risk difference (RD) -0.14, 95% CI -0.18 to -0.10; I2 = 69% for RR and 62% for RD (moderate heterogeneity); number needed to treat for an additional beneficial outcome (NNTB) 7, 95% CI 6 to 10; 19 studies, 1750 infants). The quality of the evidence was low.Necrotising enterocolitis was significantly reduced in the ESA group compared with the placebo group (typical RR 0.69, 95% CI 0.52 to 0.91; typical RD -0.03, 95% CI -0.05 to -0.01; I2 = 0% for RR and 22% for RD (low heterogeneity); NNTB 33, 95% CI 20 to 100; 15 studies, 2639 infants). The quality of the evidence was moderate.Data show a reduction in 'Any neurodevelopmental impairment at 18 to 22 months' corrected age in the ESA group (typical RR 0.62, 95% CI 0.48 to 0.80; typical RD -0.08, 95% CI -0.12 to -0.04; NNTB 13, 95% CI 8 to 25. I2 = 76% for RR (high heterogeneity) and 66% for RD (moderate); 4 studies, 1130 infants). The quality of the evidence was low.Results reveal increased scores on the Bayley-II Mental Development Index (MDI) at 18 to 24 months in the ESA group (weighted mean difference (WMD) 8.22, 95% CI 6.52 to 9.92; I2 = 97% (high heterogeneity); 3 studies, 981 children). The quality of the evidence was low.The total volume of RBCs transfused per infant was reduced by 7 mL/kg. The number of RBC transfusions per infant was minimally reduced, but the number of donors to whom infants who were transfused were exposed was not significantly reduced. Data show no significant difference in risk of stage ≥ 3 retinopathy of prematurity (ROP) with early EPO (typical RR 1.24, 95% CI 0.81 to 1.90; typical RD 0.01, 95% CI -0.02 to 0.04; I2 = 0% (no heterogeneity) for RR; I2 = 34% (low heterogeneity) for RD; 8 studies, 1283 infants). Mortality was not affected, but results show significant reductions in the incidence of intraventricular haemorrhage (IVH) and periventricular leukomalacia (PVL).

AUTHORS' CONCLUSIONS

Early administration of ESAs reduces the use of red blood cell (RBC) transfusions, the volume of RBCs transfused, and donor exposure after study entry. Small reductions are likely to be of limited clinical importance. Donor exposure probably is not avoided, given that all but one study included infants who had received RBC transfusions before trial entry. This update found no significant difference in the rate of ROP (stage ≥ 3) for studies that initiated EPO treatment at less than eight days of age, which has been a topic of concern in earlier versions of this review. Early EPO treatment significantly decreased rates of IVH, PVL, and NEC. Neurodevelopmental outcomes at 18 to 22 months and later varied in published studies. Ongoing research should evaluate current clinical practices that will limit donor exposure. Promising but conflicting results related to the neuro protective effect of early EPO require further study. Very different results from the two largest published trials and high heterogeneity in the analyses indicate that we should wait for the results of two ongoing large trials before drawing firm conclusions. Administration of EPO is not currently recommended because limited benefits have been identified to date. Use of darepoetin requires further study.

Neuroimaging in former preterm children who received erythropoiesis stimulating agents

BackgroundIn premature children, erythropoiesis-stimulating agents (ESAs) may improve developmental outcome. It is not clear which of the several potential mechanisms are responsible for this improvement. High-resolution MRI and diffusion tensor imaging characterize brain structure and white matter organization, offering possible insight into the long-term effect of ESAs on brain development.MethodsMRI scans were performed at 3.5-4 years of age on former preterm infants treated with ESAs or placebo, and on healthy term controls. Mean cortical thickness, surface area, and fractional anisotropy (FA) were compared across study groups, and were correlated with general IQ measures.ResultsUnivariate analysis found no significant effect of ESAs on cortical thickness (P=0.366), surface area (P=0.940), or FA (P=0.150); however, there was a greater increase in FA among ESA-treated girls. Group analysis found significant correlations between FA and Full-Scale IQ (P=0.044) and Verbal IQ (P=0.036), although there was no significant relationship between Full-Scale IQ and FA among just the preterm children.ConclusionESA treatment may have a preferential effect on white matter development in girls, although factors other than just whole-brain FA are involved in mediating cognitive outcome.

Neonatal mouse hippocampus: phlebotomy-induced anemia diminishes and treatment with erythropoietin partially rescues mammalian target of rapamycin signaling

BackgroundPhlebotomy-induced anemia (PIA) is common in premature infants and affects neurodevelopment. PIA alters hippocampal metabolism in neonatal mice through tissue hypoxia and iron deficiency. The mammalian target of rapamycin (mTOR) pathway senses the status of critical metabolites (e.g., oxygen, iron), thereby regulating hippocampal growth and function. We determined the effect of PIA and recombinant human erythropoietin (rHuEpo) treatment on mTOR signaling and expression of genes related to mTOR pathway functions.MethodsMice receiving an iron-supplemented diet were phlebotomized from postnatal day (P)3 to a target hematocrit of <25% by P7. Half were maintained at <25% until P14; half received rHuEpo from P7 to increase the hematocrit to 25-28%. Hippocampal phosphorylated to total protein ratios of four key mTOR pathway proteins were measured by western blotting at P14 and compared with non-phlebotomized, non-anemic control mice. mRNA levels of genes regulated by mTOR were measured by quantitative PCR.ResultsPIA suppressed phosphorylation of all mTOR proteins. rHuEpo restored AMP-activated protein kinase (AMPK) and AKT status, and partially rescued the mTOR output protein S6K. PIA and rHuEpo treatment also altered the expression of genes regulated by S6K.ConclusionPIA compromises and rHuEpo treatment partially rescues a pathway regulating neuronal DNA transcription, protein translation, and structural complexity.

Randomized trial of early erythropoietin supplementation after preterm birth: Iron metabolism and outcome

BACKGROUND

Excess of iron and oxidant injury shortly after birth may be associated with neonatal morbidities in preterm infants.

AIMS

The aim was to determine whether administration of erythropoietin without iron supplementation decreases iron load and morbidity.

STUDY DESIGN AND SUBJECTS

In a randomized trial, we administered erythropoietin (EPO 250IU/kg daily during the first 6days of life) or placebo to 39 preterm infants (BW 700-1500g, GA≤30.0weeks).

OUTCOME MEASURES

The iron status, postnatal morbidities and follow-up at the age of two years were investigated.

RESULTS

In all, 21 EPO- and 18 placebo-treated infants were recruited. A requirement of red blood cell transfusions during first 28days was similar between the study groups. EPO treatment decreased total serum iron concentration (p=0.035). EPO supplementation had no significant effect on serum transferrin receptors or reactive non-protein-bound iron. There were no differences in neonatal morbidity or in survival without major neurological abnormality at two years of age.

CONCLUSIONS

A 6-day course of EPO decreased the iron load in preterm infants. There was no change in reactive, non-protein bound iron plasma levels and no influence on the outcomes during early childhood. Whether the neurocognitive effects of early EPO treatment can be detectable later in childhood remained to be verified.

Prophylactic Early Erythropoietin for Neuroprotection in Preterm Infants: A Meta-analysis

CONTEXT

Recombinant human erythropoietin (rhEPO) is a promising pharmacological agent for neuroprotection in neonates.

OBJECTIVE

To investigate whether prophylactic rhEPO administration in very preterm infants improves neurodevelopmental outcomes in a meta-analysis of randomized controlled trials (RCTs).

DATA SOURCES

Medline, Embase, and the Cochrane Central Register of Controlled Trials were searched in December 2016 and complemented by other sources.

STUDY SELECTION

RCTs investigating the use of rhEPO in preterm infants versus a control group were selected if they were published in a peer-reviewed journal and reported neurodevelopmental outcomes at 18 to 24 months' corrected age.

DATA EXTRACTION

Data extraction and analysis followed the standard methods of the Cochrane Neonatal Review Group. The primary outcome was the number of infants with a Mental Developmental Index (MDI) <70 on the Bayley Scales of Infant Development. Secondary outcomes included a Psychomotor Development Index <70, cerebral palsy, visual impairment, and hearing impairment.

RESULTS

Four RCTs, comprising 1133 infants, were included in the meta-analysis. Prophylactic rhEPO administration reduced the incidence of children with an MDI <70, with an odds ratio (95% confidence interval) of 0.51 (0.31-0.81), P < .005. The number needed to treat was 14. There was no statistically significant effect on any secondary outcome.

CONCLUSIONS

Prophylactic rhEPO improved the cognitive development of very preterm infants, as assessed by the MDI at a corrected age of 18 to 24 months, without affecting other neurodevelopmental outcomes. Current and future RCTs should investigate optimal dosing and timing of prophylactic rhEPO and plan for long-term neurodevelopmental follow-up.

Impact of Erythropoiesis-Stimulating Agents on Behavioral Measures in Children Born Preterm

OBJECTIVE

To evaluate the impact of erythropoiesis-stimulating agents (ESAs) administered during initial hospitalization and family demographic factors on behavior at 3.5-4 years of age.

STUDY DESIGN

Children were enrolled who had previously participated in a randomized study of ESAs (n = 35) or placebo (n = 14) in infants born preterm with birth weights of 500-1250 g. A term healthy control group (n = 22) also was recruited. Behavior was evaluated by parent report with the Behavioral Assessment System of Children-2. Principal component analyses identified 2 demographic factors, a Socioeconomic Composite (SEC) and a Family Stress Composite. A multivariate general linear model evaluated the impact of study group and sex on the 4 composite scales of the Behavioral Assessment System of Children-2. Demographic factors were treated as covariates and interactions with study group (ESA, placebo, and term) were examined.

RESULTS

The ESA group had significantly better scores than the placebo group on behavioral symptoms (P = .04) and externalizing scales (P = .04). An interaction was observed between study group and SEC (P = .001). A beneficial effect of ESAs was maximal in the children with lower SEC scores.

CONCLUSIONS

The beneficial effects of ESAs on childhood behavior were maximal in children with lower SEC scores. ESAs seemed to ameliorate the adverse impact of lower SEC on behavioral domains seen in the placebo group. This effect was independent of the beneficial effect of ESAs on global cognition we reported previously.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01207778 and NCT00334737.

Erythropoietin Restores Long-Term Neurocognitive Function Involving Mechanisms of Neuronal Plasticity in a Model of Hyperoxia-Induced Preterm Brain Injury

Cerebral white and grey matter injury is the leading cause of an adverse neurodevelopmental outcome in prematurely born infants. High oxygen concentrations have been shown to contribute to the pathogenesis of neonatal brain damage. Here, we focused on motor-cognitive outcome up to the adolescent and adult age in an experimental model of preterm brain injury. In search of the putative mechanisms of action we evaluated oligodendrocyte degeneration, myelination, and modulation of synaptic plasticity-related molecules. A single dose of erythropoietin (20,000 IU/kg) at the onset of hyperoxia (24 hours, 80% oxygen) in 6-day-old Wistar rats improved long-lasting neurocognitive development up to the adolescent and adult stage. Analysis of white matter structures revealed a reduction of acute oligodendrocyte degeneration. However, erythropoietin did not influence hypomyelination occurring a few days after injury or long-term microstructural white matter abnormalities detected in adult animals. Erythropoietin administration reverted hyperoxia-induced reduction of neuronal plasticity-related mRNA expression up to four months after injury. Thus, our findings highlight the importance of erythropoietin as a neuroregenerative treatment option in neonatal brain injury, leading to improved memory function in adolescent and adult rats which may be linked to increased neuronal network connectivity.

High-Dose Erythropoietin and Hypothermia for Hypoxic-Ischemic Encephalopathy: A Phase II Trial

OBJECTIVE

To determine if multiple doses of erythropoietin (Epo) administered with hypothermia improve neuroradiographic and short-term outcomes of newborns with hypoxic-ischemic encephalopathy.

METHODS

In a phase II double-blinded, placebo-controlled trial, we randomized newborns to receive Epo (1000 U/kg intravenously; n = 24) or placebo (n = 26) at 1, 2, 3, 5, and 7 days of age. All infants had moderate/severe encephalopathy; perinatal depression (10 minute Apgar <5, pH <7.00 or base deficit ≥15, or resuscitation at 10 minutes); and received hypothermia. Primary outcome was neurodevelopment at 12 months assessed by the Alberta Infant Motor Scale and Warner Initial Developmental Evaluation. Two independent observers rated MRI brain injury severity by using an established scoring system.

RESULTS

The mean age at first study drug was 16.5 hours (SD, 5.9). Neonatal deaths did not significantly differ between Epo and placebo groups (8% vs 19%, P = .42). Brain MRI at mean 5.1 days (SD, 2.3) showed a lower global brain injury score in Epo-treated infants (median, 2 vs 11, P = .01). Moderate/severe brain injury (4% vs 44%, P = .002), subcortical (30% vs 68%, P = .02), and cerebellar injury (0% vs 20%, P = .05) were less frequent in the Epo than placebo group. At mean age 12.7 months (SD, 0.9), motor performance in Epo-treated (n = 21) versus placebo-treated (n = 20) infants were as follows: Alberta Infant Motor Scale (53.2 vs 42.8, P = .03); Warner Initial Developmental Evaluation (28.6 vs 23.8, P = .05).

CONCLUSIONS

High doses of Epo given with hypothermia for hypoxic-ischemic encephalopathy may result in less MRI brain injury and improved 1-year motor function.