Comparative Growth Outcomes in Very Low Birth Weight Infants: Evaluating Different Feeding Strategies

OBJECTIVES

To assess the growth pattern of preterm, very low birth weight (VLBW) appropriate for gestational age (AGA) infants on three different feeding regimens.

METHODS

This prospective open label three-arm parallel randomized controlled trial was conducted at neonatal intensive care unit, Kasturba Hospital, Manipal. One hundred twenty VLBW (weight between 1000-1500 g and gestational age 28-32 wk) preterm AGA infants admitted from April 2021 through September 2022 were included. Three feeding regimens were compared: Expressed breast milk (EBM); EBM supplemented with Human milk fortifier (HMF); EBM supplemented with Preterm formula feed (PTF). Primary outcome measure was assessing the growth parameters such as weight, length, head circumference on three different feeding regimens at birth 2, 3, 4, 5 and 6 wk/discharge. Secondary outcomes included incidence of co-morbidities and cost-effectiveness.

RESULTS

Of 112 infants analyzed, Group 2 supplemented with HMF showed superior growth outcomes by 6th wk/discharge of intervention, with mean weight of 2053±251 g, mean length of 44.6±1.9 cm, and mean head circumference of 32.9±1.4 cm. However, infants in Group 3, supplemented with PTF, registered mean weight of 1968±203 g, mean length of 43.6±2.0 cm, and mean head circumference of 32.0±1.6 cm. Infants exclusively on EBM presented with mean weight of 1873±256 g, mean length of 43.0±2.0 cm and mean head circumference of 31.4±1.6 cm.

CONCLUSIONS

Addition of 1 g of HMF to 25 ml of EBM in neonates weighing 1000-1500 g showed better weight gain and head circumference at 6 wk/discharge, which was statistically significant. However, no significant differences in these parameters were observed at postnatal or 2, 3, 4, and 5 wk.

Early versus late fortification of breast milk in preterm infants: a systematic review and meta-analysis

This systematic review and meta-analysis assessed the effects of early fortification (EF) versus late fortification (LF) of breast milk (BM) on growth of preterm infants. Randomized and quasi-randomized controlled trials (RCTs) dealing with the effects of EF versus LF on growth parameters, incidence of adverse events, and duration of hospital stay in preterm infants were included. Data were pooled using the RevMan 5.3 software. Quality of evidence for predefined outcomes was analyzed by GRADE. Available evidence (3 RCTs, 309 preterm infants) showed no statistically significant difference between EF and LF of BM for any of the growth parameters-weight (standardized mean difference (SMD) 0.13; 95% confidence interval (CI) - 0.09, 0.36); length (SMD 0.02; 95% CI - 0.20, 0.25); and head circumference (SMD - 0.10; 95% CI - 0.33, 0.12). Total parenteral nutrition days were similar. Duration of hospital stay was significantly higher with EF (MD 4.29; 95% CI 0.84, 7.75) with a trend of non-significant increase in feed intolerance and necrotizing enterocolitis (NEC).Conclusion: Very low quality evidence did not find any significant difference in growth parameters of preterm infants in association with EF or LF of BM. A significant increase in hospital stay and non-significant increase in feed intolerance and NEC were associated with EF.PROSPERO registration number: CRD42019139235What is Known:• Fortification of breast milk with essential macro- and micronutrients is necessary for optimization of nutrition in preterm infants.• There is no consensus regarding the breast milk feeding volume at which fortification should be initiated.What is New:• Very low quality evidence showed no significant difference between early and late fortification of breast milk on growth parameters of preterm infants.• Early fortification was associated with non-significant increase in feed intolerance and necrotizing enterocolitis and a significant increase in hospital stay.

Human Milk Supplements: Principles, Practices, and Current Controversies

Human milk is the most optimal source of nutrition for preterm and term infants. However, in most preterm infants, breast milk fails to meet the energy needs of the newborn infant. Overwhelming evidence supports the fortification of breast milk in preterm infants to facilitate better short-term outcomes. Several single-nutrient and multinutrient breast milk supplements and fortifiers are used to improve the macronutrient and micronutrient content of breast milk. An individualized fortification strategy has the potential to offer better results compared with standard fortification strategies. Human milk-derived fortification is promising, but the benefits in exclusively human milk-fed preterm infants are unclear.

Letter to the editor: clarifying some aspects and the terminology of individualized human milk fortification

This letter has been written by the components of the European Milk Bank Association (EMBA) Working Group on Human Milk Fortification in response to a recent paper published by Mathes et al. (BMC Pediatr. 2018 May 8;18(1):154) with the aim of drawing attention to the importance of the use of a metabolic marker to adapt protein intake in preterm infants. EMBA Working Group on Human Milk Fortification clarifies further the terminology and some specific aspects regarding individualized human milk fortification. There are two types of individualized human milk fortification: Adjustable human milk fortification and Targeted human milk fortification. Advantages and disadvantages of these methods are summarized.

What should be the protein target for adjustable Human Milk fortification in premature infants?

Objective:

To assess the short- and long-term effects of the adjustable fortification (ADJ) regimen on growth parameters in premature infants and to evaluate the amount of protein supplements given to reach the targeted blood urea nitrogen (BUN) levels.

Methods:

In this retrospective study, preterm babies who were born at ≤32 weeks gestational age and fed with human milk, were evaluated in two groups. Infants in Group-I were fed only standard fortification (STD). Infants in Group-II were fed the ADJ regimen. The study was conducted between 2011 and 2016.

Results:

There were 123 infants in the STD group and 119 in the ADJ group. The mean gestational age of the patients in Group-I was 29.7±1.8 weeks, and mean birth weight was 1266.1±347.1 g. The mean gestational age of the patients in Group-II was 29.5±1.9 weeks, and the mean birth weight was 1217.5±345.5 g. The daily increase in weight and weekly increase in HC were significantly higher in the ADJ group infants. Weight and HC of infants in the ADJ group were significantly higher at 40 weeks. At one year corrected age, weight, length, and HC measurements of both groups were similar. In Group-II, 63% of patients required additional protein supplementation up to 1.6 g/day to achieve the target BUN levels.

Conclusion:

A higher protein intake through the ADJ regimen improves the physical growth rate of premature infants in the NICU and after discharge. However, sometimes, the targeted growth and BUN values cannot be achieved despite the administration of protein at the recommended increased doses. Increasing protein supplementation up to 1.6 g/day is safe, feasible, and beneficial for these infants.

A randomized controlled trial comparing the effect of fortification of human milk with an infant formula powder versus unfortified human milk on the growth of preterm very low birth weight infants

Objective: To optimize growth in very low birth weight (VLBW) infants, human milk fortification is standard of care in neonatal units of high-income countries. However, commercial fortifiers may not be available or it may be too expensive in resource-limited settings. As an alternative to using human milk fortifiers, we studied the effects of milk fortification with an infant formula on growth and biochemical parameters of very low birth weight (VLBW) infantsMethods: We undertook a prospective, randomized controlled trial in the neonatal unit of a tertiary care hospital in South India. Preterm infants weighing <1500 grams and <34 weeks of gestation were randomized after stratification according to birth weight into two groups (<1250 g and 1250 to <1500 g). One group received fortified human milk while the other received exclusive human milk. The fortification was done with a commercially available infant milk powder added to expressed breast milk (when the infant reached 150 ml/kg/day of feeds) and continued till the infant reached 1800 g. The primary outcome was the rate of weight gain/kg/day. Secondary outcome measures were linear growth, head circumference increase, biochemical parameters to assess the adequacy or excess of protein supplementation and comorbidities like feed intolerance, sepsis, and necrotizing enterocolitis (NEC).Results: Total of 163 babies were randomized during the study period, of whom 148 babies (73 in the standard arm and 75 in the fortification arm) completed the trial. Baseline demographic data among the two groups were comparable. Weight gain/kg/day (mean difference (MD) 1.98 g/kg/day; 95% CI: 1.03-2.92; p<.001) and linear growth (MD 0.09 cm/week; 95% CI: 0.02-0.2; p=.02) was significantly higher in the fortification arm as compared to the control arm. The head growth (head circumference gain in cm/week) was higher and length of hospital stay lesser in the fortification arm, though not statistically significant. Biochemical parameters, rates of sepsis, feed intolerance, and necrotizing enterocolitis (NEC) were not different between the two groups.Conclusion: Fortification with Infant milk powder achieves better growth parameters than unfortified human milk and can be a useful alternative for feeding preterm VLBW infants in low resource settings.

The fortification method relying on assumed human milk composition overestimates the actual energy and macronutrient intakes in very preterm infants

Background

To achieve recommended nutrient intakes in preterm infants, the target fortification method of human milk (HM) was proposed as an alternative to standard fortification method. We aimed to compare assumed energy and macronutrient intakes based on standard fortified HM with actual intakes relying on measured composition of human milk (HM), in a cohort of HM-fed very preterm infants.

Methods

This study is a secondary retrospective analysis, in which assumed energy and macronutrient contents of daily pools of own mother’s milk (OMM) from 33 mothers and donated HM (DHM) delivered to infants were compared with the measured values using a mid-infrared HM analyzer. A fortification method consisting of modular protein and/or fat supplements added to standard fortified HM was used to provide the minimum recommended daily intakes of energy 110 Kcal/kg and protein up to 4.0 g/kg. Assumed nutrient intakes were compared with actual nutrient intakes from full enteral feeding to 35 weeks plus 6 days postmenstrual age, using the Wilcoxon matched-pairs signed ranks test.

Results

The composition of 1181 samples of daily pools of HM were measured. For 90.2% of study days, infants were exclusively fed OMM and in remaining days fed OMM plus DHM. Comparing with reported preterm OMM composition, measured protein concentration was significantly lower, and energy and other macronutrient concentrations were lower only from the second to third postnatal week. Using fortified HM, the actual median daily intakes of energy, protein, and fat were significantly lower (113.3 vs. 120.7 Kcal/kg, 4.45 vs. 4.73 g/kg, and 4.96 vs. 5.35 g/kg, respectively) and the actual protein-to-energy ratio (PER) significantly higher than what was assumed (4.2 vs. 4.0), without differences in carbohydrate intake.

Conclusions

When fortifying the HM, we used conservative target intakes trying not to exceed the osmolarity recommended for infant feeds. Actual energy, protein and fat intakes in OMM were significantly lower than assumed. This resulted in inadequate intake using our fortification method, that did not compensate the suboptimal measured energy and macronutrient contents of OMM delivered. Further studies comparing assumed with the gold standard target fortification are needed to determine safe upper limits of assumed fortification.

Does fortification of pasteurized donor human milk increase the incidence of necrotizing enterocolitis among preterm neonates? A randomized controlled trial

Objective: To compare the effect of fortified pasteurized donor human milk (PDHM) versus unfortified PDHM on the incidence of necrotizing enterocolitis (NEC) and immediate outcome among preterm neonates. Methods: This randomized controlled trial (RCT) conducted in a tertiary care teaching hospital, south India included 80 healthy preterm neonates randomized to two groups (Group A and B). Neonates in Group A and B were fed with fortified PDHM and unfortified PDHM, respectively. Neonates in both groups were managed uniformly as per standard NICU protocol. The primary outcome was the incidence of NEC and the secondary outcomes included severity of NEC, incidence of sepsis, mortality, duration of hospital stay, number of days to reach full enteral feeds and weight gain. Neonates were followed up for 28 days or discharge whichever was earlier. Results: The baseline maternal and neonatal characteristics in both groups were comparable. There was no increase in incidence of NEC in fortified PDHM group compared to unfortified PDHM group (2.5 versus 7.5%, p = .31). Severity of NEC, incidence of sepsis, mortality, duration of hospital stay, number of days to reach full enteral feeds and weight gain were also similar in both groups. Conclusions: Standard fortification of PDHM does not increase the incidence of NEC among preterm neonates.

Comparing different methods of human breast milk fortification using measured v. assumed macronutrient composition to target reference growth: a randomised controlled trial

The variable content of human breast milk suggests that its routine fortification may result in sub-optimal nutritional intakes and growth. In a pragmatic trial, we randomised infants born below 30 weeks of gestation to either the intervention (Igp) of fortifying milk on measured composition according to birth weight criteria and postmenstrual age (PMA) or our routine practice (RPgp) of fortifying on assumed milk composition to target 3·8-4·4 g protein/kg per d and 545-629 kJ/kg per d. Milk composition was measured using the MIRIS® Human Milk Analyser. Percentage fat mass (%FM) was measured using PEA POD (COSMED). The effects of macronutrient intakes and clinical variables on growth were assessed using mixed model analysis. Mean measured protein content (1·6 g/100 ml) was higher than the assumed value (1·4 g/100 ml), often leading to lower amounts of fortifier added to the milk of intervention infants. At discharge (Igp v. RPgp), total protein (3·2 (SD 0·3) v. 3·4 (SD 0·4) g; P=0·067) and energy (456 (SD 39) v. 481 (SD 48) kJ; P=0·079) intakes from all nutrition sources, weight gain velocity (11·4 (SD 1·4) v. 12·1 (SD 1·6) g/kg per d; P=0·135) and %FM (13·7 (SD 3·6) v.13·6 (SD 3·5) %; P=0·984) did not significantly differ between groups. A protein intake >3·4 g/kg per d reduced %FM by 2%. Nutrition and growth was not improved by targeting milk fortification according to birth weight criteria and PMA using measured milk composition, compared with routine practice. Targeting fortification on measured composition is labour intensive, requiring frequent milk sampling and precision measuring equipment, perhaps reasons for its limited practice. Guidance around safe upper levels of milk fortification is needed.

Fortification of human milk in very low birth weight infants (VLBW <1500 g birth weight)

The American Academy of Pediatrics supports the feeding of human milk for all infants. Very-low-birth-weight and extremely low-birth-weight infants especially can benefit from the immune and neurodevelopmental effects of human milk. However, human milk alone is nutritionally inadequate for the rapid growth of the very-low-birth-weight infant during a critical window for brain development and requires fortification to meet current recommendations. There are a variety of products, devices, and strategies that can be used to fine tune nutritional support of these very vulnerable infants.