Nutritional Support for Moderate-to-Late-Preterm Infants - A Randomized Trial.

BACKGROUND: Most moderate-to-late-preterm infants need nutritional support until they are feeding exclusively on their mother's breast milk. Evidence to guide nutrition strategies for these infants is lacking. METHODS: We conducted a multicenter, factorial, randomized trial involving infants born at 32 weeks 0 days' to 35 weeks 6 days' gestation who had intravenous access and whose mothers intended to breast-feed. Each infant was assigned to three interventions or their comparators: intravenous amino acid solution (parenteral nutrition) or dextrose solution until full feeding with milk was established; milk supplement given when maternal milk was insufficient or mother's breast milk exclusively with no supplementation; and taste and smell exposure before gastric-tube feeding or no taste and smell exposure. The primary outcome for the parenteral nutrition and the milk supplement interventions was the body-fat percentage at 4 months of corrected gestational age, and the primary outcome for the taste and smell intervention was the time to full enteral feeding (150 ml per kilogram of body weight per day or exclusive breast-feeding). RESULTS: A total of 532 infants (291 boys [55%]) were included in the trial. The mean (±SD) body-fat percentage at 4 months was similar among the infants who received parenteral nutrition and those who received dextrose solution (26.0±5.4% vs. 26.2±5.2%; adjusted mean difference, -0.20; 95% confidence interval [CI], -1.32 to 0.92; P = 0.72) and among the infants who received milk supplement and those who received mother's breast milk exclusively (26.3±5.3% vs. 25.8±5.4%; adjusted mean difference, 0.65; 95% CI, -0.45 to 1.74; P = 0.25). The time to full enteral feeding was similar among the infants who were exposed to taste and smell and those who were not (5.8±1.5 vs. 5.7±1.9 days; P = 0.59). Secondary outcomes were similar across interventions. Serious adverse events occurred in one infant. CONCLUSIONS: This trial of routine nutrition interventions to support moderate-to-late-preterm infants until full nutrition with mother's breast milk was possible did not show any effects on the time to full enteral feeding or on body composition at 4 months of corrected gestational age. (Funded by the Health Research Council of New Zealand and others; DIAMOND Australian New Zealand Clinical Trials Registry number, ACTRN12616001199404.).

Sex-Specific Effects of Nutritional Supplements for Infants Born Early or Small: An Individual Participant Data Meta-Analysis (ESSENCE IPD-MA) I-Cognitive Function and Metabolic Risk.

Neonatal nutritional supplements are widely used to improve growth and development but may increase risk of later metabolic disease, and effects may differ by sex. We assessed effects of supplements on later development and metabolism. We searched databases and clinical trials registers up to April 2019. Participant-level data from randomised trials were included if the intention was to increase macronutrient intake to improve growth or development of infants born preterm or small-for-gestational-age. Co-primary outcomes were cognitive impairment and metabolic risk. Supplementation did not alter cognitive impairment in toddlers (13 trials, n = 1410; adjusted relative risk (aRR) 0.88 [95% CI 0.68, 1.13]; p = 0.31) or older ages, nor alter metabolic risk beyond 3 years (5 trials, n = 438; aRR 0.94 [0.76, 1.17]; p = 0.59). However, supplementation reduced motor impairment in toddlers (13 trials, n = 1406; aRR 0.76 [0.60, 0.97]; p = 0.03), and improved motor scores overall (13 trials, n = 1406; adjusted mean difference 1.57 [0.14, 2.99]; p = 0.03) and in girls not boys (p = 0.03 for interaction). Supplementation lowered triglyceride concentrations but did not affect other metabolic outcomes (high-density and low-density lipoproteins, cholesterol, fasting glucose, blood pressure, body mass index). Macronutrient supplementation for infants born small may not alter later cognitive function or metabolic risk, but may improve early motor function, especially for girls.

Sex-Specific Effects of Nutritional Supplements for Infants Born Early or Small: An Individual Participant Data Meta-Analysis (ESSENCE IPD-MA) II: Growth.

Neonatal nutritional supplements may improve early growth for infants born small, but effects on long-term growth are unclear and may differ by sex. We assessed the effects of early macronutrient supplements on later growth. We searched databases and clinical trials registers from inception to April 2019. Participant-level data from randomised trials were included if the intention was to increase macronutrient intake to improve growth or development of infants born preterm or small-for-gestational-age. Co-primary outcomes were cognitive impairment and metabolic risk. Supplementation did not alter BMI in childhood (kg/m2: adjusted mean difference (aMD) -0.11[95% CI -0.47, 0.25], p = 0.54; 3 trials, n = 333). Supplementation increased length (cm: aMD 0.37[0.01, 0.72], p = 0.04; 18 trials, n = 2008) and bone mineral content (g: aMD 10.22[0.52, 19.92], p = 0.04; 6 trials, n = 313) in infancy, but not at older ages. There were no differences between supplemented and unsupplemented groups for other outcomes. In subgroup analysis, supplementation increased the height z-score in male toddlers (aMD 0.20[0.02, 0.37], p = 0.03; 10 trials, n = 595) but not in females, and no significant sex interaction was observed (p = 0.21). Macronutrient supplementation for infants born small may not alter BMI in childhood. Supplementation increased growth in infancy, but these effects did not persist in later life. The effects did not differ between boys and girls.

Strategies in Neonatal Care to Promote Growth and Neurodevelopment of the Preterm Infant.

Recommendations for nutrition of very preterm and very low birth weight infants have developed over time with our understanding of the requirements of preterm babies and the awareness of widespread poor postnatal growth. In general, the trend has been towards enhancing nutrition, but more recent recommendations have begun to raise questions with respect to the potential for high and early nutritional intakes, particularly of protein, to carry risks such as refeeding syndrome. However, large gaps in our knowledge remain for both macro- and micronutrient requirements to support optimal growth and how nutrition and growth relate to important long-term outcomes. Closing these knowledge gaps has been hampered by inconsistent reporting of nutrition intakes and growth parameters, small trials with short-term outcomes and the use of a variety of different methods of monitoring growth. The challenge now is for future research to address these issues through consensus building around the important questions that need to be answered, how to report data from neonatal nutritional trials and whether large trials answering important questions can take place through development of consortia that undertake similar trials in multiple jurisdictions with agreements to share data.

Relationships between Neonatal Nutrition and Growth to 36 Weeks' Corrected Age in ELBW Babies-Secondary Cohort Analysis from the Provide Trial.

A key modifiable factor for improving neurodevelopment in extremely low birthweight (ELBW) babies may be improving growth, especially head growth, by optimising nutrition in the early neonatal period. We aimed to investigate relationships between nutrient intakes in the 4 weeks after birth, and growth from birth to 36 weeks' corrected age (CA) in ELBW babies. We undertook a prospective cohort study of 434 participants enrolled in a randomised controlled trial (ProVIDe) in eight New Zealand and Australian neonatal intensive care units. Macronutrient intakes from birth to 4 weeks and weight, length and head circumference measurements from birth to 36 weeks' CA were collected. From birth to 36 weeks' CA, the median (IQR) z-score changes were: weight -0.48 (-1.09, 0.05); length -1.16 (-1.86, -0.43), and head circumference -0.82 (-1.51, -0.19). Changes in z-score to 4 weeks and 36 weeks' CA were correlated with protein intake. Each 1 g·Kg-1·d-1 total protein intake in week 2 was associated with 0.26 z-score increase in head circumference at 36 weeks' CA. Both nutritional intake and change in z-scores to 36 weeks' CA differed widely amongst sites. Correlations between nutrition and growth, and differences in these amongst sites, indicate there may be potential to improve growth with enhanced nutrition practices.

Growth and Clinical Outcome in Very Low-Birth-Weight Infants After the Introduction of a Multicomponent Intravenous Lipid Emulsion.

BACKGROUND: Very low-birth-weight (VLBW; birth weight < 1500 g) infants are often dependent on intravenous nutrition after birth. Conventional soy-based intravenous lipid emulsions (Soy LE) are associated with inflammatory and metabolic complications that may be harmful to preterm infants. Evidence to support any clinical benefit associated with newer multicomponent emulsions (Mixed LE), remains inconsistent and unsubstantiated in appropriate studies. This retrospective study aimed to determine whether growth and clinical outcomes differed between VLBW infants given Mixed LE vs Soy LE at Auckland City Hospital. METHODS: Data were collected on nutrition, growth, and neonatal morbidities for the first 4 weeks after birth. Outcomes were compared between 2 lipid cohorts, Soy LE (February 2013 - August 2014) and Mixed LE (August 2014 - December 2015), using univariate and multivariate analysis. RESULTS: 207 infants (Soy LE, 105 vs Mixed LE, 102) were included in the study. Significantly fewer infants in the Mixed LE cohort developed any stage retinopathy of prematurity (Soy LE 59% vs Mixed LE 39%, P = .005) or intraventricular hemorrhage (Soy LE 27% vs Mixed LE 15%, P = .03) during their admission. Mixed LE was also associated with significantly lower mean (P = .01), minimum (P = .03), and maximum (P = .04) total bilirubin concentrations across the first 4 weeks after birth. There was no difference in growth velocity or weight, length, and head circumference z-score change. CONCLUSION: SMOFlipid may represent a favorable alternative to conventional lipid emulsions in neonatal parenteral nutrition regimens; however, long-term effects should be further evaluated.

Sex-specific effects of nutritional supplements in infants born early or small: protocol for an individual participant data meta-analysis (ESSENCE IPD-MA).

INTRODUCTION: Preterm and small for gestational age (SGA) infants are at increased risk of poor growth, disability and delayed development. While growing up they are also at increased risk of obesity, diabetes and later heart disease. The risk of such adverse outcomes may be altered by how preterm and SGA infants are fed after birth. Faltering postnatal growth is common due to failure to achieve recommended high energy and protein intakes, and thus preterm and SGA infants are often provided with supplemental nutrition soon after birth. Enhanced nutrition has been associated with improved early growth and better cognitive development. However, limited evidence suggests that faster growth may increase the risk for later adiposity, metabolic and cardiovascular disease, and that such risks may differ between girls and boys. METHODS AND ANALYSIS: We will search Ovid MEDLINE, Embase, Cochrane CENTRAL, Cochrane Database of Systematic Reviews, controlled-trials.com, ClinicalTrials.gov and anzctr.org.au for randomised trials that studied the effects of macronutrient supplements for preterm and SGA infants on (i) developmental and metabolic and (ii) growth outcomes after hospital discharge. The outcomes will be (i) cognitive impairment and metabolic risk (co-primary) and (ii) body mass index. Individual participant data (IPD) from all available trials will be included using an intention-to-treat approach. A one-stage procedure for IPD meta-analysis (MA) will be used, accounting for clustering of participants within studies. Exploratory subgroup analyses will further investigate sources of heterogeneity, including sex and size of infants, different timing, duration and type of supplements. ETHICS AND DISSEMINATION: This IPD-MA is approved by the University of Auckland Human Participants Ethics Committee (reference number: 019874). Individual studies have approval from relevant local ethics committees. Results will be disseminated in a peer-reviewed journal and presented at international conferences. PROSPERO REGISTRATION NUMBER: CRD42017072683.

Pulse oximetry screening in a midwifery-led maternity setting with high antenatal detection of congenital heart disease.

AIM: To assess local and individual factors that should be considered in the design of a pulse oximetry screening strategy in New Zealand's midwifery-led maternity setting. METHODS: An intervention study was conducted over 2 years. Three hospitals and four primary maternity units participated in the study. Post-ductal saturation levels were measured on well infants with a gestation of ≥35 weeks. Infant activity and age (hours) at the time of the test were recorded. RESULTS: Screening was performed on 16 644 of 27 172 (61%) eligible infants. The age at which the screening algorithm was initiated varied significantly among centres. The probability of achieving a pass result (saturations ≥95%) in the context of no underlying pathology ranged from .94 for an unsettled infant screened <4 hours of age to .99 (P < .001) when the test was performed after 24 hours on a settled infant. Forty-eight (0.3%) infants failed to reach saturation targets: 37 had significant pathology of which three had cardiac disease. CONCLUSION: Screening practices were influenced by the setting in which it was undertaken. Infant activity and age at the time of testing can influence saturation levels. Screening is associated with the identification of significant non-cardiac pathology.

Health professionals' views of newborn pulse oximetry screening in a midwifery-led maternity setting. "It's a good thing to do, but fund it!"

OBJECTIVE: To understand from health professionals who care for newborns their views on the introduction of pulse oximetry screening for the detection of hypoxaemia in a midwifery-led maternity setting. Although oximetry screening for newborns is internationally accepted, national screening is not yet introduced in New Zealand. In this context, we drew on maternity carers' reflections during a feasibility study of oximetry screening to provide perspectives on barriers and enablers to universal screening. METHODS: Data were generated from nine focus groups during five months of 2018 in two north island regions of New Zealand. Participants' (n = 45) opinions about the use of oximetry screening in newborns were analysed thematically using an inductive approach. FINDINGS: Overall, participants stated pulse oximetry screening was easy to do, non-invasive, and worthwhile. Midwives were reassured by screening that provided evidence of either a healthy baby or a need for urgent review. From participants' reports, we identified three themes: (1) oximetry screening for newborns is reassuring, practical and worthwhile; (2) midwifery services workload expectations and under-resourcing will hinder universal screening, and (3) location of the baby at the time of screening could impede universal access. CONCLUSION AND IMPLICATIONS FOR PRACTICE: Midwives viewed implementing a national pulse oximetry screening programme as sensible but problematic unless resourced and funded appropriately. Policymakers should view the concerns of midwives about human and physical resources as significant and account for the need to resource this screening programme appropriately as a priority before implementation.

Macronutrient Supplements in Preterm and Small-for-Gestational-Age Animals: A Systematic Review and Meta-analysis.

Early macronutrient supplementation in preterm and/or small-for-gestational-age (SGA) infants may improve growth but have detrimental effects on later cardio-metabolic health which may be sex-specific. We systematically reviewed the long-term effects of early macronutrient supplementation in preterm and SGA animals and whether these differ by sex. Using Cochrane Neonatal and SYRCLE methodologies we included random or quasi-random studies that allocated non-human mammals to macronutrient supplements or no supplements between birth and weaning and assessed post-weaning outcomes. We used random-effects models to calculate standardized mean differences (SMD) with 95% confidence intervals (CIs). Six studies provided low to very-low-quality evidence that macronutrient supplementation increased weight in juvenile rats (SMD; 95% CI: 2.13; 1.00, 3.25; 1 study, n = 24), increased leptin concentrations in older adults (1.31; 0.12, 2.51; 1 study, n = 14 male rats), but decreased leptin concentrations in young adults (-1.13; -2.21, -0.05; 1 study, n = 16 female rats) and improved spatial learning and memory (qualitative data; 1 study). There was no evidence of sex-specific effects and no overall effect on length, serum lipids, body composition, HOMA-IR, or blood pressure. Macronutrient supplements may affect later growth, metabolism, and neurodevelopment of preterm and SGA animals, but evidence is limited and low quality.

Feasibility study assessing equitable delivery of newborn pulse oximetry screening in New Zealand's midwifery-led maternity setting.

OBJECTIVES: The aim of this study was to conduct New Zealand-specific research to inform the design of a pulse oximetry screening strategy that ensures equity of access for the New Zealand maternity population. Equity is an important consideration as the test has the potential to benefit some populations and socioeconomic groups more than others. SETTING: New Zealand has an ethnically diverse population and a midwifery-led maternity service. One quaternary hospital and urban primary birthing unit (Region A), two regional hospitals (Region B) and three regional primary birthing units (Region C) from three Health Boards in New Zealand's North Island participated in a feasibility study of pulse oximetry screening. Home births in these regions were also included. PARTICIPANTS: There were 27 172 infants that satisfied the inclusion criteria; 16 644 (61%) were screened. The following data were collected for all well newborn infants with a gestation age ≥35 weeks: date of birth, ethnicity, type of maternity care provider, deprivation index and screening status (yes/no). The study was conducted over a 2-year period from May 2016 to April 2018. RESULTS: Screening rates improved over time. Infants born in Region B (adjusted OR=0.75; 95% CI 0.67 to 0.83) and C (adjusted OR=0.29; 95% CI 0.27 to 0.32) were less likely to receive screening compared with those born in Region A. There were significant associations between screening rates and deprivation, ethnicity and maternity care provider. Lack of human and material resources prohibited universal access to screening. CONCLUSION: A pulse oximetry screening programme that is sector-led is likely to perpetuate inequity. Screening programmes need to be designed so that resources are distributed in the way most likely to optimise health outcomes for infants born with cardiac anomalies. ETHICS APPROVAL: This study was approved by the Health and Disability Ethics Committees of New Zealand (15/NTA/168).

Advances in nutrition of the newborn infant.

Nutrition of newborn infants, particularly of those born preterm, has advanced substantially in recent years. Extremely preterm infants have high nutrient demands that are challenging to meet, such that growth faltering is common. Inadequate growth is associated with poor neurodevelopmental outcomes, and although improved early growth is associated with better cognitive outcomes, there might be a trade-off in terms of worse metabolic outcomes, although the contribution of early nutrition to these associations is not established. New developments include recommendations to increase protein supply, improve formulations of parenteral lipids, and provide mineral supplements while encouraging human milk feeding. However, high quality evidence of the risks and benefits of these developments is lacking. Clinical trials are also needed to assess the effect on preterm infants of experiencing the smell and taste of milk, to determine whether boys and girls should be fed differently, and to test effects of insulin and IGF-1 supplements on growth and developmental outcomes. Moderate-to-late preterm infants have neonatal nutritional challenges that are similar to those infants born at earlier gestations, but even less high quality evidence exists upon which to base clinical decisions. The focus of research in nutrition of infants born at term is largely directed at new formula products that will improve cognitive and metabolic outcomes. Providing the most effective nutrition to preterm infants should be prioritised as an important focus of neonatal care research to improve long-term metabolic and developmental outcomes.

Brief neonatal nutritional supplementation has sex-specific effects on glucose tolerance and insulin regulating genes in juvenile lambs.

BACKGROUND: The nutritional plane and composition during fetal life can impact upon growth and epigenetic regulation of genes affecting pancreatic ß-cell development and function. However, it is not clear whether ß-cell development can be altered by nutritional factors or growth rate after birth. We therefore investigated the effect of neonatal nutritional supplements on growth, glucose tolerance, and pancreatic development in lambs. METHODS: Newborn lambs were randomized to daily nutritional supplements, calculated to increase macronutrient intake to a similar degree as human breast milk fortifier, or an equivalent volume of water, for 2 wk while continuing to suckle ewe milk. Intravenous glucose tolerance test (IVGTT) was performed at 4 mo of age, and pancreata collected for molecular analysis. RESULTS: Supplemented lambs had slower weight gain than controls. In supplemented lambs, insulin response to IVGTT was increased in males but decreased in females, compared to same sex controls, and was unrelated to growth rate. mRNA expression of key genes in ß-cell development showed sexually dimorphic effects. Epigenetic change occurred in the promotor region of PDX1 gene with decreased suppression and increased activation marks in supplemented lambs of both sexes. CONCLUSION: Nutritional interventions in early life have long-term, sex-specific effects on pancreatic function.

Maternal undernutrition programs tissue-specific epigenetic changes in the glucocorticoid receptor in adult offspring.

Epidemiological data indicate that an adverse maternal environment during pregnancy predisposes offspring to metabolic syndrome with increased obesity, and type 2 diabetes. The mechanisms are still unclear although epigenetic modifications are implicated and the hypothalamus is a likely target. We hypothesized that maternal undernutrition (UN) around conception in sheep would lead to epigenetic changes in hypothalamic neurons regulating energy balance in the offspring, up to 5 years after the maternal insult. We found striking evidence of decreased glucocorticoid receptor (GR) promoter methylation, decreased histone lysine 27 trimethylation, and increased histone H3 lysine 9 acetylation in hypothalami from male and female adult offspring of UN mothers. These findings are entirely compatible with the increased GR mRNA and protein observed in the hypothalami. The increased GR predicted the decreased hypothalamic proopiomelanocortin expression and increased obesity that we observed in the 5-year-old adult males. The epigenetic and expression changes in GR were specific to the hypothalamus. Hippocampal GR mRNA and protein were decreased in UN offspring, whereas pituitary GR was altered in a sex-specific manner. In peripheral polymorphonuclear leukocytes there were no changes in GR methylation or protein, indicating that this epigenetic analysis did not predict changes in the brain. Overall, these results suggest that moderate changes in maternal nutrition, around the time of conception, signal life-long and tissue-specific epigenetic alterations in a key gene regulating energy balance in the hypothalamus.

Epigenetic changes in fetal hypothalamic energy regulating pathways are associated with maternal undernutrition and twinning.

Undernutrition during pregnancy is implicated in the programming of offspring for the development of obesity and diabetes. We hypothesized that maternal programming causes epigenetic changes in fetal hypothalamic pathways regulating metabolism. This study used sheep to examine the effect of moderate maternal undernutrition (60 d before to 30 d after mating) and twinning to investigate changes in the key metabolic regulators proopiomelanocortin (POMC) and the glucocorticoid receptor (GR) in fetal hypothalami. Methylation of the fetal hypothalamic POMC promoter was reduced in underfed singleton, fed twin, and underfed twin groups (60, 73, and 63% decrease, respectively). This was associated with reduced DNA methyltransferase activity and altered histone methylation and acetylation. Methylation of the hypothalamic GR promoter was decreased in both twin groups and in maternally underfed singleton fetuses (52, 65, and 55% decrease, respectively). This correlated with changes in histone methylation and acetylation and increased GR mRNA expression in the maternally underfed singleton group. Alterations in GR were hypothalamic specific, with no changes in hippocampi. Unaltered levels of OCT4 promoter methylation indicated gene-specific effects. In conclusion, twinning and periconceptional undernutrition are associated with epigenetic changes in fetal hypothalamic POMC and GR genes, potentially resulting in altered energy balance regulation in the offspring.

Epigenetic changes in the hypothalamic proopiomelanocortin and glucocorticoid receptor genes in the ovine fetus after periconceptional undernutrition.

Maternal food restriction is associated with the development of obesity in offspring. This study examined how maternal undernutrition in sheep affects the fetal hypothalamic glucocorticoid receptor (GR) and the appetite-regulating neuropeptides, proopiomelanocortin (POMC) and neuropeptide Y, which it regulates. In fetuses from ewes undernourished from -60 to +30 d around conception, there was increased histone H3K9 acetylation (1.63-fold) and marked hypomethylation (62% decrease) of the POMC gene promoter but no change in POMC expression. In the same group, acetylation of histone H3K9 associated with the hypothalamic GR gene was increased 1.60-fold and the GR promoter region was hypomethylated (53% decrease). In addition, there was a 4.7-fold increase in hypothalamic GR expression but no change in methylation of GR gene expression in the anterior pituitary or hippocampus. Interestingly, hypomethylation of both POMC and GR promoter markers in fetal hypothalami was also identified after maternal undernutrition from -60 to 0 d and -2 to +30 d. In comparison, the Oct4 gene, was hypermethylated in both control and underfed groups. Periconceptional undernutrition is therefore associated with marked epigenetic changes in hypothalamic genes. Increase in GR expression in the undernourished group may contribute to fetal programming of a predisposition to obesity, via altered GR regulation of POMC and neuropeptide Y. These epigenetic changes in GR and POMC in the hypothalamus may also predispose the offspring to altered regulation of food intake, energy expenditure, and glucose homeostasis later in life.

A chronic low dose infusion of insulin-like growth factor I alters placental function but does not affect fetal growth.

Knowledge of the anabolic effects of insulin-like growth factor I (IGF-I) on fetal growth and feto-placental metabolism are derived from studies using large doses of IGF-I. Low doses of enteral IGF-I have trophic effects on the fetal gut, but there are no data on the effects of systemic low doses of IGF-I on fetal growth and feto-placental metabolism. We therefore compared the effects of a chronic infusion of low dose IGF-I (50 microg day(-1), n = 7) with vehicle-infused controls (n = 7) on fetal growth, metabolism and placental transfer capacity in the chronically instrumented late gestation ovine fetus (121-132 days of gestation; term = 145 days). Insulin-like growth factor I infusion did not affect fetal growth or the size of individual organs, including liver, spleen and bone. Placental morphology was altered, and placental clearances of 3-O-[methyl-3H]D-glucose (a non-metabolizable glucose analogue) and [methyl(14C)]aminoisobutyric acid (a non-metabolizable analogue of amino acids utilizing the system A transporter), were reduced in IGF-I-treated fetuses (P < 0.05 v. control). However, fetal and placental metabolite uptake was not significantly different between groups. We conclude that, despite altering placental transfer capacity and morphology, a chronic low dose infusion of IGF-I does not alter fetal growth or metabolism.