Fecal microbiome and metabolome of infants fed bovine MFGM supplemented formula or standard formula with breast-fed infants as reference: a randomized controlled trial

Human milk delivers an array of bioactive components that safeguard infant growth and development and maintain healthy gut microbiota. Milk fat globule membrane (MFGM) is a biologically functional fraction of milk increasingly linked to beneficial outcomes in infants through protection from pathogens, modulation of the immune system and improved neurodevelopment. In the present study, we characterized the fecal microbiome and metabolome of infants fed a bovine MFGM supplemented experimental formula (EF) and compared to infants fed standard formula (SF) and a breast-fed reference group. The impact of MFGM on the fecal microbiome was moderate; however, the fecal metabolome of EF-fed infants showed a significant reduction of several metabolites including lactate, succinate, amino acids and their derivatives from that of infants fed SF. Introduction of weaning food with either human milk or infant formula reduces the distinct characteristics of breast-fed- or formula-fed- like infant fecal microbiome and metabolome profiles. Our findings support the hypothesis that higher levels of protein in infant formula and the lack of human milk oligosaccharides promote a shift toward amino acid fermentation in the gut. MFGM may play a role in shaping gut microbial activity and function.

The Swedish Neonatal Quality Register - contents, completeness and validity

AIM

To describe the Swedish Neonatal Quality Register (SNQ) and to determine its completeness and agreement with other registers.

METHODS

SNQ collects data for infants admitted to neonatal units during the first four postnatal weeks. Completeness and registers' agreement were determined cross-linking SNQ data with Swedish population registers (the Inpatient, Medical Birth and Cause of Death Registers) for a study period of five years.

RESULTS

In total, 84 712 infants were hospitalised. A total of 52 806 infants occurred in both SNQ and the population registers; 28 692 were only found in the population registers, and 3214 infants were only found in SNQ. Between gestational weeks 24-34, completeness of SNQ was 98-99%. Below and above these gestational ages, completeness was lower. Infants missing in SNQ were term or near-term in 99% of the cases, and their diagnoses indicated conditions managed in maternity units, or re-admissions for acute infections, managed in paediatric units. For most diagnoses, the agreement between SNQ and population registers was high, but some (bronchopulmonary dysplasia and grade of hypoxic-ischaemic encephalopathy) were often missing in the population registers.

CONCLUSION

SNQ completeness and agreement against other registers, especially for preterm infants, is excellent. SNQ is a valid tool for benchmarking, quality improvement and research.

Validation of the diagnosis of necrotising enterocolitis in a Swedish population-based observational study

Aim

The definition of necrotising enterocolitis (NEC) is based on clinical and radiological signs that can be difficult to interpret. The aim of the present study was to validate the incidence of NEC in the Extremely Preterm Infants in Sweden Study (EXPRESS)

Methods

The EXPRESS study consisted of all 707 infants born before 27 + 0 gestational weeks during the years 2004–2007 in Sweden. Of these infants, 38 were recorded as having NEC of Bell stage II or higher. Hospital records were obtained for these infants. Furthermore, to identify missed cases, all infants with a sudden reduction of enteral nutrition, in the EXPRESS study were identified (n = 71). Hospital records for these infants were obtained. Thus, 108 hospital records were obtained and scored independently by two neonatologists for NEC.

Results

Of 38 NEC cases in the EXPRESS study, 26 were classified as NEC after validation. Four cases not recorded in the EXPRESS study were found. The incidence of NEC decreased from 6.3% to 4.3%.

Conclusion

Validation of the incidence of NEC revealed over‐ and underestimation of NEC in the EXPRESS study despite carefully collected data. Similar problems may occur in other national data sets or quality registers.

Palm Oil and Beta-palmitate in Infant Formula: A Position Paper by the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) Committee on Nutrition

BACKGROUND

Palm oil (PO) is used in infant formulas in order to achieve palmitic acid (PA) levels similar to those in human milk. PA in PO is esterified predominantly at the SN-1,3 position of triacylglycerol (TAG), and infant formulas are now available in which a greater proportion of PA is in the SN-2 position (typical configuration in human milk). As there are some concerns about the use of PO, we aimed to review literature on health effects of PO and SN-2-palmitate in infant formulas.

METHODS

PubMed and Cochrane Database of Systematic Reviews were systematically searched for relevant studies on possible beneficial effects or harms of either PO or SN-2-palmitate in infant formula on various health outcomes.

RESULTS

We identified 12 relevant studies using PO and 21 studies using SN-2-palmitate. Published studies have variable methodology, subject characteristics, and some are underpowered for the key outcomes. PO is associated with harder stools and SN-2-palmitate use may lead to softer stool consistency. Bone effects seem to be short-lasting. For some outcomes (infant colic, faecal microbiota, lipid metabolism), the number of studies is very limited and summary evidence inconclusive. Growth of infants is not influenced. There are no studies published on the effect on markers of later diseases.

CONCLUSIONS

There is insufficient evidence to suggest that PO should be avoided as a source of fat in infant formulas for health reasons. Inclusion of high SN-2-palmitate fat blend in infant formulas may have short-term effects on stool consistency but cannot be considered essential.

Cardiometabolic risk factors in children born with marginally low birth weight: A longitudinal cohort study up to 7 years-of-age

Introduction

Low birth weight (LBW, <2500 g) may predict an increased risk of an adverse cardiometabolic profile later in life, but long-term effects in different populations and birth weight strata are still unclear. We explored laboratory markers of cardiometabolic risk in children born with marginally LBW (2000–2500 g).

Methods

This was a prospective longitudinal cohort study including 285 Swedish marginally LBW children and 95 normal birth weight (NBW, 2501–4500 g) controls. At 3.5 and 7 years of age, blood samples for glucose, insulin, homeostatic model assessment for insulin resistance (HOMA-IR), cholesterol, triglycerides, high- and low density lipoprotein (HDL and LDL), apolipoprotein B (ApoB) and apolipoprotein A1 (ApoA1) were assessed and compared between the groups.

Results

No significant differences in levels of insulin, HOMA-IR, hs-CRP or blood lipids were observed between marginally LBW and NBW children. At 7 years there was a higher proportion of marginally LBW children with elevated levels of insulin, defined as above the 90^th percentile of the control group (21% vs 8.6%, p = 0.038). This association was, however, confounded by maternal ethnicity. In marginally LBW children born small for gestational age (SGA), mean fasting glucose was significantly higher compared to controls (4.7 vs 4.5 mmol/L, p = 0.020).

Conclusions

There were no significant differences in insulin, insulin resistance, hs-CRP or blood lipids between the marginally LBW children and controls. The subgroup of marginally LBW children born SGA may present early signs of glucose imbalance already at school age.

Association Between Year of Birth and 1-Year Survival Among Extremely Preterm Infants in Sweden During 2004-2007 and 2014-2016

Importance

Since 2004-2007, national guidelines and recommendations have been developed for the management of extremely preterm births in Sweden. If and how more uniform management has affected infant survival is unknown.

Objective

To compare survival of extremely preterm infants born during 2004-2007 with survival of infants born during 2014-2016.

Design, Setting and Participants

All births at 22-26 weeks' gestational age (n = 2205) between April 1, 2004, and March 31, 2007, and between January 1, 2014, and December 31, 2016, in Sweden were studied. Prospective data collection was used during 2004-2007. Data were obtained from the Swedish pregnancy, medical birth, and neonatal quality registries during 2014-2016.

Exposures

Delivery at 22-26 weeks' gestational age.

Main Outcomes and Measures

The primary outcome was infant survival to the age of 1 year. The secondary outcome was 1-year survival among live-born infants who did not have any major neonatal morbidity (specifically, without intraventricular hemorrhage grade 3-4, cystic periventricular leukomalacia, necrotizing enterocolitis, retinopathy of prematurity stage 3-5, or severe bronchopulmonary dysplasia).

Results

During 2004-2007, 1009 births (3.3/1000 of all births) occurred at 22-26 weeks' gestational age compared with 1196 births (3.4/1000 of all births) during 2014-2016 (P = .61). One-year survival among live-born infants at 22-26 weeks' gestational age was significantly lower during 2004-2007 (497 of 705 infants [70%]) than during 2014-2016 (711 of 923 infants [77%]) (difference, -7% [95% CI, -11% to -2.2%], P = .003). One-year survival among live-born infants at 22-26 weeks' gestational age and without any major neonatal morbidity was significantly lower during 2004-2007 (226 of 705 infants [32%]) than during 2014-2016 (355 of 923 infants [38%]) (difference, -6% [95% CI, -11% to -1.7%], P = .008).

Conclusions and Relevance

Among live births at 22-26 weeks' gestational age in Sweden, 1-year survival improved between 2004-2007 and 2014-2016.

Physiological Effects of Feeding Infants and Young Children Formula Supplemented with Milk Fat Globule Membranes

Dietary supplementation with bovine milk fat globule membrane (MFGM) concentrates has recently emerged as a possible means to improve the health of infants and young children. Formula-fed infants are of special interest since infant formulas traditionally have lower concentrations of biologically active MFGM components than human milk. We identified 6 double-blind randomized controlled trials (DBRCT) exploring the effects of supplementing the diet of infants and children with bovine MFGM concentrates. Two studies found a positive effect on cognitive development in formula-fed infants. Three studies found a protective effect against infections at different ages during infancy and early childhood. We conclude that supplementation with MFGM during infancy and childhood appears safe, and the studies indicate positive effects on both neurodevelopment and defense against infections, especially in formula-fed infants. However, due to the small number of studies and the heterogeneity of interventions and outcomes, more high-quality DBRCTs are needed before firm conclusions can be drawn on the likely health benefits of MFGM supplementation to infants and children.

Use of Concentrated Parenteral Nutrition Solutions Is Associated With Improved Nutrient Intakes and Postnatal Growth in Very Low-Birth-Weight Infants

Background

Evidence showing the beneficial effects of enhanced parenteral nutrition (PN) to very low‐birth‐weight (VLBW, <1500 g) infants is accumulating. However, PN composition and its impact on growth outcomes are questioned. This study aimed to investigate the associations between administration of a concentrated PN regime and intakes of energy and macronutrients as well as postnatal growth in VLBW infants.

Methods

We compared 2 cohorts of VLBW infants born before (n = 74) and after (n = 44) a concentrated PN regime was introduced into clinical use. Daily nutrition and fluid intake during the first 28 postnatal days and all available growth measurements during hospitalization were retrospectively collected from clinical charts.

Results

Infants who received concentrated PN compared with original PN had higher parenteral intakes of energy (56 vs 45 kcal/kg/d, P < 0.001), protein (2.6 vs 2.2 g/kg/d, P = 0.008), and fat (1.5 vs 0.7 g/kg/d, P < 0.001) during the first postnatal week. Changes in standard deviation scores for weight and length from birth to postnatal day 28 were more positive in the concentrated PN group (mean [95% CI]; weight change: –0.77 [–1.02 to –0.52] vs –1.29 [–1.33 to –1.05], P = 0.005; length change: –1.01 [–1.36 to –0.65] vs –1.60 [–1.95 to –1.25], P = 0.025). There were no significant differences in fluid intake and infant morbidity between the groups.

Conclusion

Our results suggest that concentrated PN is useful and seems to be safe for improving early nutrition and growth in VLBW infants.

Postnatal nutritional intakes and hyperglycemia as determinants of blood pressure at 6.5 years of age in children born extremely preterm

BACKGROUND

Adverse developmental programming by early-life exposures might account for higher blood pressure (BP) in children born extremely preterm. We assessed associations between nutrition, growth and hyperglycemia early in infancy, and BP at 6.5 years of age in children born extremely preterm.

METHODS

Data regarding perinatal exposures including nutrition, growth and glycemia status were collected from the Extremely Preterm Infants in Sweden Study (EXPRESS), a population-based cohort including infants born <27 gestational weeks during 2004-2007. BP measurements were performed at 6.5 years of age in a sub-cohort of 171 children (35% of the surviving children).

RESULTS

Higher mean daily protein intake (+1 g/kg/day) during postnatal weeks 1-8 was associated with 0.40 (±0.18) SD higher diastolic BP. Higher mean daily carbohydrate intake (+1 g/kg/day) during the same period was associated with 0.18 (±0.05) and 0.14 (±0.04) SD higher systolic and diastolic BP, respectively. No associations were found between infant growth (weight, length) and later BP. Hyperglycemia and its duration during postnatal weeks 1-4 were associated primarily with higher diastolic BP z-scores.

CONCLUSIONS

These findings emphasize the importance of modifiable early-life exposures, such as nutrition and hyperglycemia, in determining long-term outcomes in children born extremely preterm.

Reference intervals for reticulocyte hemoglobin content in healthy infants

OBJECTIVES

Iron deficiency anemia in childhood is a serious public health problem worldwide. Reticulocyte hemoglobin content (Ret-He) is a novel biomarker of iron deficiency adopted for adults but there is a lack of reference intervals for Ret-He in infants. The aim of this study was to provide data from healthy infants.

METHODS

Swedish infants (n = 456), born at term after normal pregnancies were included. Ret-He was measured at birth (umbilical cord sample), 48-72 h, 4 months, and 12 months. Reference intervals were calculated as ±2 standard deviations from the mean of Ret-He.

RESULTS

Reference intervals for newborn Ret-He were 27.4 to 36.0 pg/L (N = 376) in the cord sample, 28.1-37.7 pg/L (N = 253) at 48-72 h, 25.6-33.4 pg/L (N = 341) at four months and 24.9-34.1 pg/L (N = 288) at 12 months. Ret-He was significantly lower among iron-deficient infants, at 4 months mean difference (95% CI) -4.2 pg/L (-6.1 to -2.4) and at 12 months mean difference (95% CI) -3.4 pg/L (-5.0 to -1.8).

CONCLUSIONS

This longitudinal study presents Ret-He reference intervals based on non-anemic and non-iron-deficient infants and constitutes a step towards standardizing Ret-He as a pre-anemia biomarker of iron deficiency in children.

Serum, plasma and erythrocyte membrane lipidomes in infants fed formula supplemented with bovine milk fat globule membranes

BACKGROUND

Supplementation of formula with bovine milk fat globule membranes has been shown to narrow the gap in immunological and cognitive development between breast-fed and formula-fed infants.

METHOD

In a double-blinded randomized controlled trial 160 formula-fed infants received an experimental formula (EF), supplemented with bovine milk fat globule membranes, or standard formula until 6 months of age. A breast-fed reference group was recruited. Lipidomic analyses were performed on plasma and erythrocyte membranes at 6 months and on serum at 4 and 12 months of age.

RESULTS

At 6 months of age, we observed a significant separation in the plasma lipidome between the two formula groups, mostly due to differences in concentrations of sphingomyelins (SM), phosphatidylcholines (PC), and ceramides, and in the erythrocyte membrane lipidome, mostly due to SMs, PEs and PCs. Already at 4 months, a separation in the serum lipidome was evident where SMs and PCs contributed. The separation was not detected at 12 months.

CONCLUSIONS

The effect of MFGM supplementation on the lipidome is likely part of the mechanisms behind the positive cognitive and immunological effects of feeding the EF previously reported in the same study population.

Hyperglycemia in Extremely Preterm Infants-Insulin Treatment, Mortality and Nutrient Intakes

OBJECTIVE

To explore the prevalence of hyperglycemia and the associations between nutritional intakes, hyperglycemia, insulin treatment, and mortality in extremely preterm infants.

STUDY DESIGN

Prospectively collected data from the Extremely Preterm Infants in Sweden Study (EXPRESS) was used in this study and included 580 infants born <27 gestational weeks during 2004-2007. Available glucose measurements (n = 9850) as well as insulin treatment and nutritional data were obtained retrospectively from hospital records for the first 28 postnatal days as well as 28- and 70-day mortality data.

RESULTS

Daily prevalence of hyperglycemia >180 mg/dL (10 mmol/L) of up to 30% was observed during the first 2 postnatal weeks, followed by a slow decrease in its occurrence thereafter. Generalized additive model analysis showed that increasing parenteral carbohydrate supply with 1 g/kg/day was associated with a 1.6% increase in glucose concentration (P < .001). Hyperglycemia was associated with more than double the 28-day mortality risk (P < .01). In a logistic regression model, insulin treatment was associated with lower 28- and 70-day mortality when given to infants with hyperglycemia irrespective of the duration of the hyperglycemic episode (P < .05).

CONCLUSIONS

Hyperglycemia is common in extremely preterm infants throughout the first postnatal month. Glucose infusions seem to have only a minimal impact on glucose concentrations. In the EXPRESS cohort, insulin treatment was associated with lower mortality in infants with hyperglycemia. Current practices of hyperglycemia treatment in extremely preterm infants should be reevaluated and assessed in randomized controlled clinical trials.

The Swedish Approach to Management of Extreme Prematurity at the Borderline of Viability: A Historical and Ethical Perspective

Sweden has a long tradition of being at the forefront of the management of extremely preterm infants. In this article, we explore the historical background, ethical discussions, and evidence from national surveys combined with data from quality registers that form the background of the current Swedish guidelines for the care of extremely preterm infants. The current Swedish national guidelines suggest providing active care for preterm infants from 23 weeks' gestation and considering active care from 22 weeks' gestation. The survival of infants in gestational weeks 22 and 23 has increased and now exceed 50% and 60%, respectively; importantly, the Swedish proactive approach to care at the border of viability has not resulted in an increased proportion of functional impairment among survivors.

Lower cognitive test scores at age 7 in children born with marginally low birth weight

BackgroundBeing born with very low birth weight (<1500 g) is associated with poorer neurocognition later in life. The aim of this study was to explore neurodevelopmental functions in those born with marginally LBW (2000-2500 g).MethodsThis was originally a randomized controlled trial investigating the effects of early iron supplementation in 285 marginally LBW children. Herein, we explored the combined marginally LBW group and compared their results to 95 normal birth weight (NBW; 2501-4500 g) controls in an observational design. At 7 years, a pediatric psychologist tested the children using Wechsler Intelligence Scale for Children (WISC IV), Beery-Buktenica developmental test of Visual-Motor Integration (Beery VMI), and Test of Everyday Attention for Children (TEA-Ch).ResultsThe marginally LBW children had lower verbal comprehension intelligence quotient (IQ) (104 vs. 107, P=0.004), lower VMI scores (96.5 vs. 100, P=0.028), and lower total mean TEA-Ch scores (8.5 vs. 9.7, P=0.006), compared to controls. Also, the marginally LBW children group had a higher proportion of children below -1 SD for VMI and TEA-Ch.ConclusionsMarginally LBW children had lower verbal comprehension IQ, lower visual-motor integration, and lower attention performance than NBW children, suggesting an increased risk of cognitive difficulties in early school age.

Early energy and protein intakes and associations with growth, BPD, and ROP in extremely preterm infants

BACKGROUND & AIM

Extremely preterm infants face substantial neonatal morbidity. Nutrition is important to promote optimal growth and organ development in order to reduce late neonatal complications. The aim of this study was to examine the associations of early nutritional intakes on growth and risks of bronchopulmonary dysplasia (BPD) and retinopathy of prematurity (ROP) in a high-risk population.

METHODS

This population-based cohort study includes infants born before 27 0/7 weeks of gestational age without severe malformations and surviving ≥10 days. Intake of energy and protein on postnatal days 4-6 and association with weight standard deviation score (WSDS) from birth to day 7, as well as intakes of energy and protein on postnatal days 4-6 and 7 to 27, respectively, and association with composite outcome of death and BPD and separate outcomes of BPD and ROP were examined, and adjusted for potential confounders.

RESULTS

The cohort comprised 296 infants with a median gestational age of 25 3/7 weeks. Expressed as daily intakes, every additional 10 kcal/kg/d of energy during days 4-6 was associated with 0.08 higher WSDS on day 7 (95% CI 0.06-0.11; p < 0.001). Between days 7 and 27, every 10 kcal/kg/d increase in energy intake was associated with a reduced risk of BPD of 9% (95% CI 1-16; p = 0.029) and any grade of ROP with a reduced risk of 6% (95% CI 2-9; p = 0.005) in multivariable models. This association was statistically significant in infants with ≤10 days of mechanical ventilation. In infants with >10 days of mechanical ventilation, a combined higher intake of energy and protein was associated with a reduced risk of BPD.

CONCLUSION

Early provision of energy and protein may reduce postnatal weight loss and risk of morbidity in extremely preterm infants.

Role of iodine-containing multivitamins during pregnancy for children's brain function: protocol of an ongoing randomised controlled trial: the SWIDDICH study

INTRODUCTION

Iodine is essential for normal brain development. Moderate and severe fetal iodine deficiency results in substantial to serious developmental delay in children. Mild iodine deficiency in pregnancy is associated with neurodevelopmental deficits in the offspring, but evidence from randomised trials is lacking. The aim of the Swedish Iodine in Pregnancy and Development in Children study is to determine the effect of daily supplementation with 150 µg iodine during pregnancy on the offspring's neuropsychological development up to 14 years of age.

METHODS AND ANALYSIS

Thyroid healthy pregnant women (n=1275: age range 18-40 years) at ≤12 weeks gestation will be randomly assigned to receive multivitamin supplements containing 150 µg iodine or non-iodine-containing multivitamin daily throughout pregnancy. As a primary outcome, IQ will be measured in the offspring at 7 years (Wechsler Intelligence Scale for Children-V). As secondary outcomes, IQ will be measured at 3.5 and 14 years, psychomotor development at 18 months and 7 years, and behaviour at 3.5, 7 and 14 years. Iodine status (urinary iodine concentration) will be measured during pregnancy and in the offspring at 3.5, 7 and 14 years. Thyroid function (thyroid hormones, thyroglobulin), and deiodinase type 2 polymorphisms will be measured during pregnancy and in the offspring at 7 and 14 years. Structural MRI or other relevant structural or functional brain imaging procedures will be performed in a subgroup of children at 7 and 14 years. Background and socioeconomic information will be collected at all follow-up times.

ETHICS AND DISSEMINATION

This study is approved by the Ethics Committee in Göteborg, Sweden (Diary numbers: 431-12 approved 18 June 2012 (pregnancy part) and 1089-16 approved 8 February 2017 (children follow-up)). According to Swedish regulations, dietary supplements are governed by the National Food Agency and not by the Medical Product Agency. Therefore, there is no requirement for a monitoring committee and the National Food Agency does not perform any audits of trial conduct. The trial will be conducted in accordance with the Declaration of Helsinki. The participating sites will be contacted regarding important protocol changes, both orally and in writing, and the trial registry database will be updated accordingly. Study results will be presented at relevant conferences, and submitted to peer-reviewed journals with open access in the fields of endocrinology, paediatrics and nutrition. After the appropriate embargo period, the results will be communicated to participants, healthcare professionals at the maternal healthcare centres, the public and other relevant groups, such as the national guideline group for thyroid and pregnancy and the National Food Agency.

TRIAL REGISTRATION NUMBER

NCT02378246; Pre-results.

The Preterm Heart in Childhood: Left Ventricular Structure, Geometry, and Function Assessed by Echocardiography in 6-Year-Old Survivors of Periviable Births

BACKGROUND

Preterm birth has been associated with increased risk of cardiovascular morbidity in adult life. We evaluated whether preterm birth is associated with deviating cardiac structure and function before school start.

METHODS AND RESULTS

In total, 176 children aged 6 years and born extremely preterm (EXPT; gestational age of 22-26 weeks) and 134 children born at term (control [CTRL]) were studied. We used echocardiography to assess left heart dimensions, geometry, and functions. Recording and off-line analyses of echocardiographic images were performed by operators blinded to group belonging. Body size, blood pressure, and heart rate were also measured. Rates of family history of cardiovascular disease and sex distribution were similar in the EXPT and CTRL groups. Heart rate and systolic blood pressure did not differ, whereas diastolic blood pressure was slightly higher in EXPT than CTRL participants. After adjusting for body surface area, left ventricular length, width, and aortic valve annulus diameter were 3% to 5% smaller in EXPT than CTRL participants. Left ventricular longitudinal shortening and systolic tissue velocity were 7% to 11% lower, and transversal shortening fraction was 6% higher in EXPT than CTRL participants. The EXPT group also exhibited lower atrial emptying velocities than the CTRL group. Sex, fetal growth restriction, or a patent ductus arteriosus in the neonatal period did not contribute to cardiac dimensions or performance.

CONCLUSIONS

Six-year-old children born extremely preterm exhibit a unique cardiac phenotype characterized by smaller left ventricles with altered systolic and diastolic functions than same-aged children born at term.

Lung function after extremely preterm birth-A population-based cohort study (EXPRESS)

BACKGROUND AND OBJECTIVES

Follow-up studies of children and young adults born very-to-moderately preterm show persistent and significant lung function deficits. The aim of the study was to determine lung function and airway mechanics in school-aged children born in 2004 to 2007 and extremely preterm (after 22-26 weeks of gestation).

METHODS

In a population-based cohort of children born extremely preterm and controls born at term (n = 350), follow-up at 6½-years-of-age was performed using spirometry and impulse oscillometry. Associations to gestational age, smallness for gestational age (SGA), and bronchopulmonary dysplasia (BPD) were assessed.

RESULTS

Children born extremely preterm had lower forced vital capacity (FVC, z-score: -0.7, 95%CI: -1.0;-0.4), forced expiratory volume (FEV₁ , z-score: -1.1, 95%CI: -1.4; -0.8), higher frequency-dependence of resistance (R_5-20 , 0.09, 95%CI: 0.05; 0.12 kPa · L^-1  · s^-1 ) and larger area under the reactance curve (AX, 0.78, 95%CI: 0.49; 1.07 kPa · L^-1 ) than controls. In children born at 22-24 weeks of gestation, 24% had FVC and 44% had FEV₁ below the lower limit of normal. SGA and severe BPD only marginally contributed to pulmonary outcomes. Asthma-like disease was reported in 40% of extremely preterm children and 15% of controls.

CONCLUSION

Many children born extremely preterm have altered airway mechanics and significant obstructive reduction in lung function. This warrants consideration for treatment and continued follow-up.

Wait a minute? An observational cohort study comparing iron stores in healthy Swedish infants at 4 months of age after 10-, 60- and 180-second umbilical cord clamping

BACKGROUND AND OBJECTIVE

Umbilical cord blood (UCB) is a valuable stem cell source used for transplantation. Immediate umbilical cord (UC) clamping is widely practised, but delayed UC clamping is increasingly advocated to reduce possible infant anaemia. The aim of this study was to investigate an intermediate UC clamping time point and to evaluate iron status at the age of 4 months in infants who had the UC clamped after 60 s and compare the results with immediate and late UC clamping.

DESIGN

Prospective observational study with two historical controls.

SETTING

A university hospital in Stockholm, Sweden, and a county hospital in Halland, Sweden.

METHODS

Iron status was assessed at 4 months in 200 prospectively recruited term infants whose UC was clamped 60 s after birth. The newborn baby was held below the uterine level for the first 30 s before placing the infant on the mother's abdomen for additional 30 s. The results were compared with data from a previously conducted randomised controlled trial including infants subjected to UC clamping at ≤10 s (n=200) or ≥180 s (n=200) after delivery.

RESULTS

After adjustment for age differences at the time of follow-up, serum ferritin concentrations were 77, 103 and 114 µg/L in the 10, 60 and 180 s groups, respectively. The adjusted ferritin concentration was significantly higher in the 60 s group compared with the 10 s group (P=0.002), while the difference between the 60 and 180 s groups was not significant (P=0.29).

CONCLUSION

In this study of healthy term infants, 60 s UC clamping with 30 s lowering of the baby below the uterine level resulted in higher serum ferritin concentrations at 4 months compared with 10 s UC clamping. The results suggest that delaying the UC clamping for 60 s reduces the risk for iron deficiency.

TRIAL REGISTRATION NUMBER

NCT01245296.

Meeting the Iron Needs of Low and Very Low Birth Weight Infants

Low birth weight (LBW), defined as a birth weight of <2,500 g, affects 16% of all newborns and is a risk factor for impaired neurodevelopment as well as adverse cardiovascular and metabolic outcomes, including hypertension. LBW infants include both term, small for gestational age infants and preterm infants. Most LBW infants have only marginally LBW (2,000-2,500 g). Recent advances in neonatal care have significantly improved the survival of very LBW (VLBW) infants (<1,500 g). LBW infants are at high risk of iron deficiency due to low iron stores at birth and higher iron requirements due to rapid growth. Using a factorial approach, iron requirements of LBW infants have been estimated to be 1-2 mg/kg/day, which is much higher than the requirements of term, normal birth weight infants, who need almost no dietary iron during the first 6 months of life. In VLBW infants, blood losses and blood transfusions related to neonatal intensive care, as well as erythropoietin treatment, will greatly influence iron status and iron requirements. The timing of umbilical cord clamping at birth is of great importance for the amount of blood transfused from the placenta to the newborn and thereby total body iron. Delayed cord clamping of LBW infants is associated with less need for blood transfusion, less intraventricular hemorrhage, and less necrotizing enterocolitis. Randomized controlled trials have shown that an iron intake of 1-3 mg/kg/day (1-2 mg for marginally LBW and 2-3 mg for VLBW) is needed to effectively prevent iron deficiency. There is some recent evidence that these levels of iron intake will prevent some of the negative health consequences associated with LBW, especially behavioral problems and other neurodevelopmental outcomes and possibly even hypertension. However, it is also important to avoid excessive iron intakes which have been associated with adverse effects in LBW infants.

Improved nutrition for extremely preterm infants - A population based observational study

BACKGROUND AND AIMS

Extremely preterm (EPT) infants are at high risk for malnutrition due to immaturity and medical complications and they often accumulate nutritional deficits and experience growth faltering during treatment at neonatal intensive care units (NICUs). Enhanced intake of energy and protein during the first weeks of life improves weight gain and head circumference growth. The optimal nutritional strategy for these infants' health and long-term development remains unknown. Nutritional regiments have been identified as a potential area for improvement in Swedish NICUs. The aim of this study was to evaluate changes in nutritional intake over time during the first 56 postnatal days in EPT (<27 gestational weeks; n = 316) infants, who were treated in NICUs during 2004-2011 in Stockholm, using a population-based study approach.

METHODS

Several different nutritional interventions were implemented over the 8-year period. Nutrition and growth data were obtained retrospectively from hospital records. All intakes of enteral and parenteral nutrients were retrieved daily during the first 28 postnatal days and on days 35, 42, 49 and 56.

RESULTS

Energy intake (median) increased from 77 kcal/kg/d during the 2004-2005 period to 98 kcal/kg/d during the 2010-2011 period on days 4-6. Median protein intake increased from 2.4 g/kg/d during 2004-2005 to 3.6 g/kg/d during 2010-2011. Energy and protein intake during postnatal days 0-6 increased continuously over the 8 years and protein intake increased during all 56 postnatal days. Full enteral feeds were reached earlier and the proportion of enteral feeds during the first week was higher during 2008-2009 compared to all other years. A significant improvement in growth was primarily noted by comparing the 2004-2005 period to subsequent years.

CONCLUSIONS

Neonatal nutrition improved significantly in Stockholm from 2004 to 2011. Above all, parenteral nutrition was initiated more promptly during the first week and was provided at higher quantities. However, many of the EPT infants born during the later years still did not reach the recommended macronutrient intake levels. A significant weight gain improvement was observed between 2004-2005 and 2006-2011.