Effects of vitamin E supplementation during erythropoietin treatment of the anaemia of prematurity

Enteral Bioactive Factor Supplementation in Preterm Infants: A Systematic Review

Feeding preterm infants with mother’s own milk is associated with a reduction in postnatal complications and an improved neurocognitive outcome. Therefore, the bioactive factor composition of human milk has been used as a tool for the development of nutritional supplements with a potential prophylactic or therapeutic effect. The aim of this systematic review was to provide an overview on bioactive factors which have been studied as supplement to enteral nutrition in randomized controlled trials, and to provide an overview of ongoing trials. MEDLINE, EMBASE, CENTRAL, and clinical trial registers were searched. Studies on the antimicrobial protein lactoferrin were excluded as these were summarized very recently in three separate systematic reviews. Studies on vitamins D, K and iron were also excluded as they are already incorporated in most international guidelines. We identified 17 different bioactive factors, which were investigated in 26 studies. Despite the encouraging potential effects of several bioactive factors, more high-quality studies with a sufficient number of preterm infants are required before a certain factor may be implemented into clinical practice. Three large trials (n > 500) that investigate the effects of either enteral insulin or vitamin A are currently ongoing and could provide more definite answers on these specific supplements.

Late erythropoiesis-stimulating agents to prevent red blood cell transfusion 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. Darbepoetin (Darbe) and EPO are currently available ESAs.

OBJECTIVES

To assess the effectiveness and safety of late initiation of ESAs, between eight and 28 days after birth, in reducing the use of red blood cell (RBC) transfusions in preterm or low birth weight infants.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL 2018, Issue 5), MEDLINE via PubMed (1966 to 5 June 2018), Embase (1980 to 5 June 2018), and CINAHL (1982 to 5 June 2018). We searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials of late initiation of EPO treatment (started at ≥ eight days of age) versus placebo or no intervention in preterm (< 37 weeks) or low birth weight (< 2500 grams) neonates.

DATA COLLECTION AND ANALYSIS

We performed data collection and analyses in accordance with the methods of the Cochrane Neonatal Review Group. We used the GRADE approach to assess the quality of the evidence.

MAIN RESULTS

We include 31 studies (32 comparisons) randomising 1651 preterm infants. Literature searches in 2018 identified one new study for inclusion. No new on-going trials were identified and no studies used darbepoetin. Most included trials were of small sample size. The meta-analysis showed a significant effect on the use of one or more RBC transfusions (21 studies (n = 1202); typical risk ratio (RR) 0.72, 95% confidence interval (CI) 0.65 to 0.79; typical risk difference (RD) -0.17, 95% CI -0.22 to -0.12; typical number needed to treat for an additional beneficial outcome (NNTB) 6, 95% CI 5 to 8). There was moderate heterogeneity for this outcome (RR I² = 66%; RD I² = 58%). The quality of the evidence was very low. We obtained similar results in secondary analyses based on different combinations of high/low doses of EPO and iron supplementation. There was no significant reduction in the total volume (mL/kg) of blood transfused per infant (typical mean difference (MD) -1.6 mL/kg, 95% CI -5.8 to 2.6); 5 studies, 197 infants). There was high heterogeneity for this outcome (I² = 92%). There was a significant reduction in the number of transfusions per infant (11 studies enrolling 817 infants; typical MD -0.22, 95% CI -0.38 to -0.06). There was high heterogeneity for this outcome (I² = 94%). Three studies including 404 infants reported on retinopathy of prematurity (ROP) (all stages or stage not reported), with a typical RR 1.27 (95% CI 0.99 to 1.64) and a typical RD of 0.09 (95% CI -0.00 to 0.18). There was high heterogeneity for this outcome for both RR (I² = 83%) and RD (I² = 82%). The quality of the evidence was very low.Three trials enrolling 442 infants reported on ROP (stage ≥ 3). The typical RR was 1.73 (95% CI 0.92 to 3.24) and the typical RD was 0.05 (95% CI -0.01 to 0.10). There was no heterogeneity for this outcome for RR (I² = 18%) but high heterogeneity for RD (I² = 79%). The quality of the evidence was very low.There were no significant differences in other clinical outcomes including mortality and necrotising enterocolitis. For the outcomes of mortality and necrotising enterocolitis, the quality of the evidence was moderate. Long-term neurodevelopmental outcomes were not reported.

AUTHORS' CONCLUSIONS

Late administration of EPO reduces the use of one or more RBC transfusions, the number of RBC transfusions per infant (< 1 transfusion per infant) but not the total volume (mL/kg) of RBCs transfused per infant. Any donor exposure is likely not avoided as most studies included infants who had received RBC transfusions prior to trial entry. Late EPO does not significantly reduce or increase any clinically important adverse outcomes except for a trend in increased risk for ROP. Further research of the use of late EPO treatment, to prevent donor exposure, is not indicated. Research efforts should focus on limiting donor exposure during the first few days of life in sick neonates, when RBC requirements are most likely to be required and cannot be prevented by late EPO treatment. The use of satellite packs (dividing one unit of donor blood into many smaller aliquots) may reduce donor exposure.

Late erythropoiesis-stimulating agents to prevent red blood cell transfusion 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. Darbepoetin (Darbe) and EPO are currently available ESAs.

OBJECTIVES

To assess the effectiveness and safety of late initiation of ESAs, between eight and 28 days after birth, in reducing the use of red blood cell (RBC) transfusions in preterm or low birth weight infants.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL 2018, Issue 5), MEDLINE via PubMed (1966 to 5 June 2018), Embase (1980 to 5 June 2018), and CINAHL (1982 to 5 June 2018). We searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials of late initiation of EPO treatment (started at ≥ eight days of age) versus placebo or no intervention in preterm (< 37 weeks) or low birth weight (< 2500 grams) neonates.

DATA COLLECTION AND ANALYSIS

We performed data collection and analyses in accordance with the methods of the Cochrane Neonatal Review Group. We used the GRADE approach to assess the quality of the evidence.

MAIN RESULTS

We include 31 studies (32 comparisons) randomising 1651 preterm infants. Literature searches in 2018 identified one new study for inclusion. No new on-going trials were identified and no studies used darbepoetin.Most included trials were of small sample size. The meta-analysis showed a significant effect on the use of one or more RBC transfusions (21 studies (n = 1202); typical risk ratio (RR) 0.72, 95% confidence interval (CI) 0.65 to 0.79; typical risk difference (RD) -0.17, 95% CI -0.22 to -0.12; typical number needed to treat for an additional beneficial outcome (NNTB) 6, 95% CI 5 to 8). There was moderate heterogeneity for this outcome (RR I² = 66%; RD I² = 58%). The quality of the evidence was very low. We obtained similar results in secondary analyses based on different combinations of high/low doses of EPO and iron supplementation. There was no significant reduction in the total volume (mL/kg) of blood transfused per infant (typical mean difference (MD) -1.6 mL/kg, 95% CI -5.8 to 2.6); 5 studies, 197 infants). There was high heterogeneity for this outcome (I² = 92%). There was a significant reduction in the number of transfusions per infant (11 studies enrolling 817 infants; typical MD -0.22, 95% CI -0.38 to -0.06). There was high heterogeneity for this outcome (I² = 94%).Three studies including 404 infants reported on retinopathy of prematurity (ROP) (all stages or stage not reported), with a typical RR 1.27 (95% CI 0.99 to 1.64) and a typical RD of 0.09 (95% CI -0.00 to 0.18). There was high heterogeneity for this outcome for both RR (I² = 83%) and RD (I² = 82%). The quality of the evidence was very low.Three trials enrolling 442 infants reported on ROP (stage ≥ 3). The typical RR was 1.73 (95% CI 0.92 to 3.24) and the typical RD was 0.05 (95% CI -0.01 to 0.10). There was no heterogeneity for this outcome for RR (I² = 18%) but high heterogeneity for RD (I² = 79%). The quality of the evidence was very low.There were no significant differences in other clinical outcomes including mortality and necrotising enterocolitis. For the outcomes of mortality and necrotising enterocolitis, the quality of the evidence was moderate. Long-term neurodevelopmental outcomes were not reported.

AUTHORS' CONCLUSIONS

Late administration of EPO reduces the use of one or more RBC transfusions, the number of RBC transfusions per infant (< 1 transfusion per infant) but not the total volume (mL/kg) of RBCs transfused per infant. Any donor exposure is likely not avoided as most studies included infants who had received RBC transfusions prior to trial entry. Late EPO does not significantly reduce or increase any clinically important adverse outcomes except for a trend in increased risk for ROP. Further research of the use of late EPO treatment, to prevent donor exposure, is not indicated. Research efforts should focus on limiting donor exposure during the first few days of life in sick neonates, when RBC requirements are most likely to be required and cannot be prevented by late EPO treatment. The use of satellite packs (dividing one unit of donor blood into many smaller aliquots) may reduce donor exposure.

Late erythropoietin for preventing red blood cell transfusion in preterm and/or low birth weight infants

BACKGROUND

Low plasma levels of erythropoietin (EPO) in preterm infants provide a rationale for the use of EPO to prevent or treat anaemia.

OBJECTIVES

To assess the effectiveness and safety of late initiation of erythropoietin (EPO) between eight and 28 days after birth, in reducing the use of red blood cell (RBC) transfusions in preterm and/or low birth weight infants.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and CINAHL in July 2013. Additional searches included the Pediatric Academic Societies Annual Meetings from 2000 to 2013 (Abstracts2View™) and clinical trials registries (www.clinicaltrials.gov; www.controlled-trials.com; and who.int/ictrp/en). For this update we moved one study from the early EPO review to this late EPO review.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials of late initiation of EPO treatment (started at ≥ eight days of age) versus placebo or no intervention in preterm (< 37 weeks) and/or low birth weight (< 2500 g) neonates.

DATA COLLECTION AND ANALYSIS

We performed data collection and analyses in accordance with the methods of the Cochrane Neonatal Review Group.

MAIN RESULTS

We include 30 studies (31 comparisons) randomising 1591 preterm infants. Literature searches in 2013 did not identify any new study for inclusion. For this update we moved one study enrolling 230 infants from the early EPO review to this late EPO review.Most included trials were of small sample size. The meta-analysis showed a significant effect of the use of one or more RBC transfusions (20 studies (n = 1142); typical risk ratio (RR) 0.71, 95% confidence interval (CI) 0.64 to 0.79; typical risk difference (RD) -0.17, 95% CI -0.22 to -0.12; typical number needed to treat for an additional beneficial outcome (NNTB) 6, 95% CI 5 to 8). There was moderate heterogeneity for this outcome (RR I² = 68%; RD I² = 60%). We obtained similar results in secondary analyses based on different combinations of high/low doses of EPO and iron supplementation. There was no significant reduction in the total volume (mL/kg) of blood transfused per infant [typical mean difference (MD) -1.6 mL/kg, 95% CI -5.8 to 2.6); 5 studies, 197 infants]. There was high heterogeneity for this outcome (I² = 92%). There was a significant reduction in the number of transfusions per infant (11 studies enrolling 817 infants; typical MD -0.22, 95% CI -0.38 to -0.06). There was high heterogeneity for this outcome (I² = 94%).Three studies including 404 infants reported on retinopathy of prematurity (ROP) (all stages or stage not reported), with a typical RR 1.27 (95% CI 0.99 to 1.64) and a typical RD of 0.09 (95% CI -0.00 to 0.18). There was high heterogeneity for this outcome for both RR (I² = 83%) and RD (I² = 82%). Three trials enrolling 442 infants reported on ROP (stage ≥ 3). The typical RR was 1.73 (95% CI 0.92 to 3.24) and the typical RD was 0.05 (95% CI -0.01 to 0.10). There was minimal heterogeneity for this outcome for RR (I² = 18%) but high heterogeneity for RD (I² = 79%). There were no significant differences in other clinical outcomes. There was no reduction in necrotizing enterocolitis in spite of a reduction in the use of RBC transfusions. Long-term neurodevelopmental outcomes were not reported.

AUTHORS' CONCLUSIONS

Late administration of EPO reduces the use of one or more RBC transfusions, the number of RBC transfusions per infant (< 1 transfusion per infant) but not the total volume (ml/kg) of RBCs transfused per infant. Any donor exposure is likely not avoided as most studies included infants who had received RBC transfusions prior to trial entry. Late EPO does not significantly reduce or increase any clinically important adverse outcomes except for a trend in increased risk for ROP. Further research of the use of late EPO treatment to prevent donor exposure is not indicated. Research efforts should focus on limiting donor exposure during the first few days of life in sick neonates, when RBC requirements are most likely to be required and cannot be prevented by late EPO treatment. The use of satellite packs (dividing one unit of donor blood into many smaller aliquots) may reduce donor exposure.

Late erythropoietin for preventing red blood cell transfusion in preterm and/or low birth weight infants

BACKGROUND

Low plasma levels of erythropoietin (EPO) in preterm infants provide a rationale for the use of EPO to prevent or treat anaemia.

OBJECTIVES

To assess the effectiveness and safety of late initiation of EPO (initiated at eight days after birth or later) in reducing the use of red blood cell (RBC) transfusions in preterm and/or low birth weight infants.

SEARCH METHODS

For this update MEDLINE, EMBASE, CINAHL, and The Cochrane Library were searched in March 2012. Additional searches included the Pediatric Academic Societies Annual Meetings from 2000 to 2012 (Abstracts2 View(TM)) and clinical trials registries (clinicaltrials.gov; controlled-trials.com; and who.int/ictrp).

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials of late initiation of EPO treatment (started at ≥ eight days of age) versus placebo or no intervention in preterm (< 37 weeks) and/or low birth weight (< 2500 g) neonates.

DATA COLLECTION AND ANALYSIS

Data collection and analyses were performed in accordance with the methods of the Cochrane Neonatal Review Group.

MAIN RESULTS

In this 2012 update one new study for inclusion was identified. Twenty-eight studies enrolling 1361 preterm infants in 21 countries were included. Most trials were of small sample size. The meta-analysis showed a significant effect on the use of one or more RBC transfusions [typical risk ratio (RR); 0.66 (95% confidence interval (CI); 0.59 to 0.74); typical risk difference (RD) -0.21 (95% CI; -0.26 to -0.16); typical number needed to benefit (NNTB) of 5 (95% CI 4 to 6) 19 studies, 912 infants]. There was moderate heterogeneity for this outcome [for RR (P < 0.00001; I(2) = 74.0%); for RD (P = 0.0006; I(2) = 58.9%)]. Similar results were obtained in secondary analyses based on different combinations of high/low doses of EPO and iron supplementation. In this update there was no significant reduction in the total volume (mL/kg) of blood transfused per infant [typical MD -1.61mL/kg (95% CI -5.78 to 2.57); 5 studies, 197 infants] There was high heterogeneity for this outcome (P = 0.00001, I(2) = 92%). There was a significant reduction in the number of transfusions per infant (nine studies enrolling 567 infants); [typical MD -0.78 (-0.97 to -0.59)]. Three studies including 331 patients reported on retinopathy of prematurity (ROP) (all stages), with a typical RR 0.79 (95% CI 0.57 to 1.10) and a typical RD of -0.05 (95% CI -0.13 to 0.02). This outcome was not statistically significantly different between the groups. There was no heterogeneity for this outcome for either RR (P = 0.41; I(2) = 0%) or RD (P = 0.43; I(2) = 0%). Two trials enrolling 212 patients reported on severe ROP (stage 3 or greater). The typical RR was 0.83 (95% CI 0.23 to 2.98) and the typical RD was -0.01 (95% CI -0.06 to 0.05); neither were statistically significant. There was no heterogeneity for this outcome for either RR (P = 0.29; I(2) = 9.3%) or RD (P = 0.36; I(2) = 0%).There were no significant differences in other clinical outcomes. Long-term neurodevelopmental outcomes were not reported.

AUTHORS' CONCLUSIONS

Late administration of EPO reduces the use of one or more RBC transfusions, the number of RBC transfusions per infant but not the total volume of RBCs transfused per infant. Any donor exposure is likely not avoided as most studies included infants who had received RBC transfusions prior to trial entry. Late EPO does not significantly reduce or increase any clinically important adverse outcomes. Further research of the use of late EPO treatment to prevent donor exposure is not indicated. Research efforts should focus on limiting donor exposure during the first few days of life in sick neonates, when RBC requirements are most likely to be required and cannot be prevented by late EPO treatment.

Dosage and formulation issues: oral vitamin E therapy in children

PURPOSE

Oral vitamin E is used in several childhood diseases, but dosage recommendations differ. Few oral products have a marketing authorization for therapeutic use in children. Preliminary data indicate differences in bioavailability among the various vitamin E compounds. Our objective was to review published data on oral vitamin E therapy in neonates and children in order to establish dosage recommendations at a local level.

METHODS

A literature search was conducted, including Medline Ovid, EMBASE (1980-Feb 2008), Cochrane databases, product monographs, handbooks, and textbooks.

RESULTS

The main vitamin E compounds being used in children are alpha-tocopherol, alpha-tocopheryl acetate, and tocofersolan. The most data are available on tocopheryl acetate, both in neonates and older children. In children with malabsorption disorders, tocofersolan appears to have an increased bioavailability compared to tocopherol or tocopheryl acetate. Published data on pharmacokinetics and dosages for clinical use are few and heterogeneous. No pharmacokinetic studies were found for tocofersolan in neonates and infants. There are few comparative studies on pharmacokinetics, therapeutic use, and adverse drug reactions (ADRs) in children. Dosages used in clinical studies and dosage recommendations in handbooks differ considerably.

CONCLUSIONS

The differences in dosing recommendations in children may be due to lack of systematic studies. Existing published data on oral vitamin E do not provide a basis for evaluation of dosage recommendations in children. Comparative clinical studies are required for scientific evaluation of pharmacokinetics, dosage regimens, and efficacy/ADR assessments in children.

Is there a role for erythropoietin in neonatal medicine?

Since it was first cloned in 1985, the therapeutic potential of recombinant human erythropoietin in the neonatal hyporegenerative anaemias has been studied-the anaemia of prematurity and haemolytic disease of the newborn. Between 60% and 100% of preterm infants are transfused before three weeks of age, a large proportion receiving more than one transfusion. Blood transfusions are currently also the mainstay of treatment for the hyporegenerative anaemia encountered in neonates with Rhesus disease. Sometimes the situation is complicated by the religious beliefs of the parents. Blood transfusions are associated with numerous risks, from transmission of infection to local injury, and in an effort to minimize these risks Neonatologists have looked to recombinant erythropoietin. Despite an extensive number of studies, there is as yet no clear consensus as to whether the use of recombinant erythropoietin in Neonatal medicine minimizes the need for blood transfusions without risk to the neonate. In this article we review the evidence for and against the use of recombinant erythropoietin in Neonatal medicine.

Vitamin E in renal therapeutic regiments

Administration of vitamin E in children with immunoglobulin A (IgA) nephropathy, focal segmental glomerulosclerosis (FSGS) and type I diabetes demonstrated potential towards ameliorating progression. Oral vitamin E therapy reduced endothelial dysfunction, lipid peroxidation and oxidative stress in patients with chronic kidney failure (CKF). Moreover, the use of vitamin E-bonded hemodialyzers reduced atherosclerotic changes, erythropoietin dosage and muscular cramps in patients on hemodialysis (HD). However, several controlled clinical trials failed to document beneficial effects on the study subjects' cardiovascular and renal outcomes. A recent report of increased all-cause mortality in adult patients receiving high dose vitamin E therapy has caused considerable concern and debate. These issues regarding the efficacy and safety of vitamin E in renal therapeutic regimens will be reviewed in this article.

Vitamin E supplementation for prevention of morbidity and mortality in preterm infants

BACKGROUND

Treating very low birth weight (VLBW) infants with pharmacologic doses of vitamin E as an antioxidant agent has been proposed for preventing or limiting retinopathy of prematurity, intracranial hemorrhage, hemolytic anemia, and chronic lung disease. However, excessive doses of vitamin E may result in side effects.

OBJECTIVES

The aim of this systematic review was to assess the effects of vitamin E supplementation on morbidity and mortality in preterm infants.

SEARCH STRATEGY

We searched MEDLINE (October 2002), EMBASE (March 2002), the Cochrane Controlled Trials Register (CCTR) from the Cochrane Library, 2003, Issue 1, and personal files for clinical trials assessing vitamin E in preterm infants.

SELECTION CRITERIA

We selected trials analyzing primary outcomes (mortality or combined long-term morbidity) or secondary outcomes (other morbidity) in infants with gestational age less than 37 weeks or birth weight less than 2500 grams. The intervention was allocation to routine supplementation with vitamin E in the treatment group versus placebo, no treatment or another type, dose or route of administration of vitamin E.

DATA COLLECTION AND ANALYSIS

We used standard methods of the Cochrane Collaboration and of the Cochrane Neonatal Review Group.

MAIN RESULTS

Twenty-six randomized clinical trials fulfilled entry criteria. No study assessed combined long-term morbidity. Routine vitamin E supplementation significantly reduced the risk of germinal/intraventricular hemorrhage (typical relative risk [RR] 0.85, 95% confidence interval [CI] 0.73, 0.99), increased the risk of sepsis (typical RR 1.52, CI 1.13, 2.04) and increased hemoglobin concentration by a small amount, but did not significantly affect mortality and other morbidity. In VLBW infants, vitamin E supplementation increased the risk of sepsis, and reduced the risk of severe retinopathy and blindness among those examined. Subgroup analyses in VLBW infants showed (1) an association between serum tocopherol levels greater than 3.5 mg/dl and increased risk of sepsis and reduced risk for severe retinopathy among those examined; and (2) an association between intravenous, high-dose administration of vitamin E and increased risk of sepsis.

REVIEWER'S CONCLUSIONS

Vitamin E supplementation in preterm infants reduced the risk of intracranial hemorrhage but increased the risk of sepsis. In very low birth weight infants it increased the risk of sepsis, and reduced the risk of severe retinopathy and blindness among those examined. Evidence does not support the routine use of vitamin E supplementation by intravenous route at high doses, or aiming at serum tocopherol levels greater than 3.5 mg/dl.