Body composition changes in preterm infants following hospital discharge: comparison with term infants

High protein intake on later outcomes in preterm children: a systematic review and meta-analysis

BACKGROUND

Appropriate protein intake is crucial for growth and development in children born preterm. We assessed the effects of high (HP) versus low protein (LP) intake on neurodevelopment, growth, and biochemical anomalies in these children.

METHODS

Randomised and quasi-randomised trials providing protein to children born preterm (<37 completed weeks of gestation) were searched following PRISMA guideline in three databases and four registers (PROSPERO registration CRD42022325659). Random-effects model was used for assessing the effects of HP (≥3.5 g/kg/d) vs. LP (<3.5 g/kg/d).

RESULTS

Data from forty-four studies (n = 5338) showed HP might slightly reduce the chance of survival without neurodisability at ≥12 months (four studies, 1109 children, relative risk [RR] 0.95 [95% CI 0.90, 1.01]; P = 0.13; low certainty evidence) and might increase risk of cognitive impairment at toddler age (two studies; 436 children; RR 1.36 [0.89, 2.09]; P = 0.16; low certainty evidence). At discharge or 36 weeks, HP intake might result in higher weight and greater head circumference z-scores. HP intake probably increased the risk of hypophosphatemia, hypercalcemia, refeeding syndrome and high blood urea, but reduced risk of hyperglycaemia.

CONCLUSIONS

HP intake for children born preterm may be harmful for neonatal metabolism and later neurodisability and has few short-term benefits for growth.

IMPACT STATEMENT

Planned high protein intake after birth for infants born preterm might be harmful for survival, neurodisability and metabolism during infancy and did not improve growth after the neonatal period. Protein intake ≥3.5 g/kg/d should not be recommended for children born preterm.

Body composition after implementation of an enhanced parenteral nutrition protocol in the neonatal intensive care unit: a randomised pilot trial

BACKGROUND

Very low birthweight (VLBW) infants are at risk for growth failure and poor neurodevelopment. Optimised parenteral nutrition may help promote optimal growth and development, but concerns that provision of enhanced nutrition may contribute to increased early adiposity and later metabolic disease remain.

AIM

To determine associations between provision of an early enhanced parenteral nutrition protocol or standard parenteral nutrition protocol and growth and body composition for VLBW preterm infants in the neonatal intensive care unit.

SUBJECTS

This is a secondary analysis of data from a clinical trial aimed at assessing the feasibility and safety of randomising VLBW preterm infants to Standard (n = 45) or Intervention (n = 42) parenteral nutrition groups between August 2017 and June 2019.

METHODS

We evaluated associations between weekly infant growth and body composition measurements from n = 55 infants (Standard = 29, Intervention = 26) that were clinically stable enough to have body composition measurements taken before discharge using mixed effects linear regression models.

RESULT

No statistically significant associations between nutrition group and infant growth or body composition measures were observed (p >.05).

CONCLUSION

In this pilot trial, enhanced parenteral nutrition in the first week of life was not associated with significant differences in infant growth or body composition during hospitalisation.

Body composition in healthy singleton term infants using the three-dimensional photonic scanning method: A multicenter cross-sectional study

OBJECTIVES

Body composition is an integral part of the nutritional assessment during infancy as it is closely related to future health. The three-dimensional photonic body surface scanning (3-DPS) method is a promising new technique for measuring body composition in children because of its advantages of easy operation, low cost, and no exposure to radiation. Using 3-DPS, this study aimed to illustrate the growth trajectories of body composition indicators during infancy according to sex and age.

METHODS

This was a multicenter cross-sectional study. The body compositions of 9644 singleton term infants from four centers in Shandong Province, China, were assessed using 3-DPS. The data of 8769 healthy infants (52.0% boys), whose z scores of weight-for-length, length-for-age, and weight-for-age, according to World Health Organization standards, were in the range of -2 to 2, -3 to 3, and -3 to 3, respectively, were sampled to construct percentile curves of fat mass (FM), fat-free mass (FFM), FM percentage (FM%), FM index (FMI), and FFM index (FFMI) with the generalized additive model for location, scale, and shape method.

RESULTS

Percentile charts for FM, FFM, FM%, FMI, and FFMI were developed based on age and sex. FM and FFM presented consistent trajectories with that of weight, with the fastest growth occurring at 1 to 3 mo of age. FM%, FMI, and FFMI increased with age, peaked at 6 mo, and gradually declined, which was consistent with the body mass index trend. All indicators, except for FFMI, were always significantly higher in boys than in girls ages 1 to 12 mo, indicating that sex differences in body composition existed mainly in FM rather than in lean body mass.

CONCLUSIONS

The body composition of healthy singleton term infants during infancy varies with age; boys may have more FM accumulation than girls.

Inflammation induces stunting by lowering bone mass via GH/IGF-1 inhibition in very preterm infants

BACKGROUND

Sustained systemic inflammatory response (SIR) was associated with poor postnatal growth in very preterm infants (VPI). We hypothesize that VPI with sustained SIR will exhibit linear growth retardation related to lower bone mass accrual mediated by GH/IGF-1 axis inhibition at term corrected age (CA).

METHODS

C-reactive protein (CRP), procalcitonin (PCT), growth hormone (GH), insulin-like growth factor 1 (IGF-1), calcium, phosphorus, alkaline phosphatase, anthropometric, nutritional, neonatal and maternal data were collected prospectively in 23 infants <32 weeks gestational age. Body composition using dual-energy X-ray absorptiometry was performed at term CA. Analysis was undertaken with multiple linear regression models.

RESULTS

At term CA 11 infants with sustained SIR compared with 12 infants without sustained SIR present significantly lower IGF-1, length z-score (LZS), bone mineral content (BMC) and lean mass (LM), and higher GH and fat mass (FM). LZS was associated significantly with PCT, BMC with IGF-1, FM and LM with CRP, GH with bronchopulmonary dysplasia and CRP, and IGF-1 with invasive mechanical ventilation, CRP and PCT.

CONCLUSIONS

In addition to the known effect on linear growth failure, sustained SIR induces lower bone mass accrual related to higher GH and lower IGF-1 levels in VPI.

IMPACT

Very preterm infants (VPI) with sustained systemic inflammatory response (SIR) compared with VPI without SIR present stunting, lower bone mass, higher GH and lower IGF-1 levels at term corrected age. SIR may help to explain the influence of non-nutritional factors on growth and body composition in VPI. SIR induces postnatal stunting related to lower bone mass accrual via GH/IGF-1 axis inhibition in VPI. VPI with SIR need special attention to minimize inflammatory stress, which could result in improved postnatal growth. Research on inflammatory-endocrine interactions involved in the pathophysiology of postnatal stunting is needed as a basis for new interventional approaches.

Maternal pregnancy-related anxiety and children's physical growth: the Ma'anshan birth cohort study

BACKGROUND

Epidemiological studies have identified maternal antenatal anxiety and several adverse birth outcomes, but limited studies have focused on the relationship with the long-term physical growth of children. The study aimed to assess the influence of maternal pregnancy-related anxiety on physical growth in children at different exposure periods during pregnancy.

METHODS

3,154 mother-child pairs were included based on the Ma'anshan birth cohort study. Maternal prenatal anxiety was obtained by administering a questionnaire using the pregnancy-related anxiety questionnaire (PRAQ) scale during the 1st, 2nd and 3rd trimesters of pregnancy. Body fat (BF) (48 to 72 months) and Body Mass Index (BMI) (birth to 72 months) were collected repeatedly for children. Group-based trajectory models were applied to fit the different trajectories of BMI and BF.

RESULTS

Maternal anxiety in the 2nd (OR = 0.81; 95% CI: 0.68 to 0.98; P < 0.025) and 3rd (OR = 0.80; 95% CI: 0.67 to 0.97; P = 0.020) trimesters was associated with a decreased risk of rapid weight gain (RWG) in the first year of life. Children aged 48 to 72 months of mothers with anxiety in the 3rd trimester had lower BMI (β = -0.161; 95% CI, -0.293 to -0.029; P = 0.017) and BF (β = -0.190; 95% CI, -0.334 to -0.046; P = 0.010), and these children were less likely to develop a very high BMI trajectory (OR = 0.54; 95% CI: 0.34 to 0.84; P = 0.006), and a high BF trajectory (OR = 0.72; 95% CI: 0.53 to 0.99; P = 0.043). Similar associations were found between maternal anxiety in both 2nd and 3rd trimesters and children's physical growth.

CONCLUSIONS

Offspring of mothers with prenatal anxiety in the 2nd and 3rd trimesters predicts poorer growth in infancy and preschool age. Early improvement and treatment of prenatal anxiety could benefit physical health and development in early childhood.

Early growth and body composition assessed by air displacement plethysmography in infants born with simple gastroschisis

BACKGROUND

Gastroschisis is an abdominal wall malformation usually associated with impaired growth.

OBJECTIVE

To evaluate the growth and body composition of infants born with simple gastroschisis in a referral center.

METHODS

This was a single-center, prospective case series of infants with simple gastroschisis who were measured at birth, at discharge, and at 3 months. Body composition was assessed via air-displacement plethysmography at discharge and at 3 months. The results were compared with those reported for healthy infants at an equivalent gestational age.

RESULTS

Simple gastroschisis infants were lighter and smaller at birth and remained similar at 3 months. All anthropometric z scores decreased from birth to discharge, followed by an increase but not a full recovery toward 3 months. Overall, gastroschisis infants had a similar FM percentage, FM% (11.1 ± 4.7), but a lower FFM, FFM (2481 ± 478 g), at discharge. FM% (18.5 ± 5.3) decreased at 3 months, and FFM remained lower (3788 ± 722 g) but improved between the two exams. Boys had significantly more FFM than girls at both evaluations. The multiple regression analysis showed that male sex, prematurity, total parenteral nutrition duration, and exclusive breast milk diets were associated with differences in body composition.

CONCLUSIONS

Infants with simple gastroschisis cared for in a referral center experienced growth failure at discharge and showed a similar FM% but lower FFM than healthy infants. At 3 months, they exhibited smaller FM% and FFM, but FFM improved after the first exam, representing a better protein accretion.

TYPE OF STUDY

Prognostic.

LEVEL OF EVIDENCE

IV.

Preterm birth and metabolic implications on later life: A narrative review focused on body composition

Preterm newborn infants are characterized by low body weight and lower fat mass at birth compared with full-term newborn neonates. Conversely, at term corrected age, body fat mass is more represented in preterm newborn infants, causing a predisposition to developing metabolic syndrome and cardiovascular diseases in later life with a different risk profile in men as compared with women. Postnatal growth is a complex change in anthropometric parameters and body composition. Both quantity and quality of growth are regulated by several factors such as fetal programming, early nutrition, and gut microbiota. Weight gain alone is not an optimal indicator of nutritional status as it does not accurately describe weight quality. The analysis of body composition represents a potentially useful tool to predict later metabolic and cardiovascular risk as it detects the quality of growth by differentiating between fat and lean mass. Longitudinal follow-up of preterm newborn infants could take advantage of body composition analysis in order to identify high-risk patients who apply early preventive strategies. This narrative review aimed to examine the state-of-the-art body composition among born preterm children, with a focus on those in the pre-school age group.

Intranasal Insulin Attenuates the Long-Term Adverse Effects of Neonatal Hyperglycemia on the Hippocampus in Rats

Hyperglycemia due to relative hypoinsulinism is common in extremely preterm infants and is associated with hippocampus-mediated long-term cognitive impairment. In neonatal rats, hypoinsulinemic hyperglycemia leads to oxidative stress, altered neurochemistry, microgliosis, and abnormal synaptogenesis in the hippocampus. Intranasal insulin (INS) bypasses the blood-brain barrier, targets the brain, and improves synaptogenesis in rodent models, and memory in adult humans with Alzheimer's disease or type 2 diabetes, without altering the blood levels of insulin or glucose. To test whether INS improves hippocampal development in neonatal hyperglycemia, rat pups were subjected to hypoinsulinemic hyperglycemia by injecting streptozotocin (STZ) at a dose of 80 mg/kg i.p. on postnatal day (P) 2 and randomized to INS, 0.3U twice daily from P3-P6 (STZ + INS group), or no treatment (STZ group). The acute effects on hippocampal neurochemical profile and transcript mRNA expression of insulin receptor (Insr), glucose transporters (Glut1, Glut4, and Glut8), and poly(ADP-ribose) polymerase-1 (Parp1, a marker of oxidative stress) were determined on P7 using in vivo 1H MR spectroscopy (MRS) and qPCR. The long-term effects on the neurochemical profile, microgliosis, and synaptogenesis were determined at adulthood using 1H MRS and histochemical analysis. Relative to the control (CONT) group, mean blood glucose concentration was higher from P3 to P6 in the STZ and STZ + INS groups. On P7, MRS showed 10% higher taurine concentration in both STZ groups. qPCR showed 3-folds higher Insr and 5-folds higher Glut8 expression in the two STZ groups. Parp1 expression was 18% higher in the STZ group and normal in the STZ + INS group. At adulthood, blood glucose concentration in the fed state was higher in the STZ and STZ + INS groups. MRS showed 59% higher brain glucose concentration and histochemistry showed microgliosis in the hippocampal subareas in the STZ group. Brain glucose was normal in the STZ + INS group. Compared with the STZ group, phosphocreatine and phosphocreatine/creatine ratio were higher, and microglia in the hippocampal subareas fewer in the STZ + INS group (p < 0.05 for all). Neonatal hyperglycemia was associated with abnormal glucose metabolism and microgliosis in the adult hippocampus. INS administration during hyperglycemia attenuated these adverse effects and improved energy metabolism in the hippocampus.

Differences in growth patterns and catch up growth of small for gestational age preterm infants fed on fortified mother's own milk versus preterm formula

Small for gestational age (SGA) is typically defined as birthweight < 10th percentile for age. Limited data are available regarding the growth of SGA preterm infants in relation to feeding type. We aimed to study SGA preterm infants fed fortified mother's own milk (MOM) or preterm formula (PF) on growth patterns and catch-up growth at discharge and two-years corrected age (CA). Our retrospective cohort study included data from medical records and follow-up questionnaires about SGA preterm infants born at <37 weeks fed on MOM (n=40) and PF (n=40). Weight, length/height and head circumference (HC) were collected at birth, discharge and at two years CA, and Δ z-scores were calculated.The MOM group had significantly larger negative change in weight and length z-scores between birth and discharge, and smaller positive change in HC z-score (-0.47 (±0.41) v. -0.25 (±0.36), P= 0.01; -0.63 (±0.75) v. -0.27 (±0.75), P= 0.03; 0.13 (±0.67) v. 0.41 (±0.55), P= 0.04, respectively). Almost half the MOM fed infants experienced poor length growth by discharge compared to 22% of PF fed infants (P=0.03). By two years CA, both groups had similar positive change in weight and HC z-scores, but MOM fed infants had a slower increase in height z-score (0.64 (±1.30) v. 1.33 (±1.33), P=0.02), and only 40% had achieved catch-up height compared with 68% of the PF group (P=0.02).Our study indicates that fortified MOM fed SGA preterm infants may need extra nutritional support in the first two years of life to achieve height growth potential.

Systemic Inflammation in the First 2 Weeks after Birth as a Determinant of Physical Growth Outcomes in Hospitalized Infants with Extremely Low Gestational Age

OBJECTIVE

To examine associations of systemic inflammation with growth outcomes at neonatal intensive care unit discharge or transfer among infants with extremely low gestational ages.

STUDY DESIGN

We studied 850 infants at born at 23-27 weeks of gestation. We defined inflammatory protein elevation as the highest quartile of C-reactive protein (CRP), Interleukin (IL)-6, tumor necrosis factor-∝, or IL-8 on postnatal days 1, 7, and 14. We compared z-scores of weight, length, and head circumference at neonatal intensive care unit discharge or transfer between infants with vs without inflammatory protein elevation, adjusting in linear regression for birth size z-score, sex, gestational age, diet, comorbidities, medications, and length of hospitalization.

RESULTS

The mean gestational age was 25 weeks (range, 23-27 weeks) and birth weight z-score 0.14 (range, -2.73 to 3.28). Infants with a high CRP on day 7 had lower weights at discharge or transfer (-0.17 z-score; 95% CI, -0.27 to -0.06) than infants without CRP elevation, with similar results on day 14. Infants with CRP elevation on day 14 were also shorter (-0.21 length z-scores; 95% CI, -0.38 to -0.04), and had smaller head circumferences (-0.18 z-scores; 95% CI, -0.33 to -0.04) at discharge or transfer. IL-6 elevation on day 14 was associated with lower weight (-0.12; 95% CI, -0.22 to -0.02); IL-6 elevation on day 7 was associated with shorter length (-0.27; 95% CI, -0.43 to -0.12). Tumor necrosis factor-∝ and IL-8 elevation on day 14 were associated with a lower weight at discharge or transfer.

CONCLUSIONS

Postnatal systemic inflammation may contribute to impaired nutrient accretion during a critical period in development in infants with extremely low gestational ages.

Metabolic-endocrine disruption due to preterm birth impacts growth, body composition, and neonatal outcome

Despite optimized nutrition, preterm-born infants grow slowly and tend to over-accrete body fat. We hypothesize that the premature dissociation of the maternal-placental-fetal unit disrupts the maintenance of physiological endocrine function in the fetus, which has severe consequences for postnatal development. This review highlights the endocrine interactions of the maternal-placental-fetal unit and the early perinatal period in both preterm and term infants. We report on hormonal levels (including tissue, thyroid, adrenal, pancreatic, pituitary, and placental hormones) and nutritional supply and their impact on infant body composition. The data suggest that the premature dissociation of the maternal-placental-fetal unit leads to a clinical picture similar to panhypopituitarism. Further, we describe how the premature withdrawal of the maternal-placental unit, neonatal morbidities, and perinatal stress can cause differences in the levels of growth-promoting hormones, particularly insulin-like growth factors (IGF). In combination with the endocrine disruption that occurs following dissociation of the maternal-placental-fetal unit, the premature adaptation to the extrauterine environment leads to early and fast accretion of fat mass in an immature body. In addition, we report on interventional studies that have aimed to compensate for hormonal deficiencies in infants born preterm through IGF therapy, resulting in improved neonatal morbidity and growth. IMPACT: Preterm birth prematurely dissociates the maternal-placental-fetal unit and disrupts the metabolic-endocrine maintenance of the immature fetus with serious consequences for growth, body composition, and neonatal outcomes. The preterm metabolic-endocrine disruption induces symptoms resembling anterior pituitary failure (panhypopituitarism) with low levels of IGF-1, excessive postnatal fat mass accretion, poor longitudinal growth, and failure to thrive. Appropriate gestational age-adapted nutrition alone seems insufficient for the achievement of optimal growth of preterm infants. Preliminary results from interventional studies show promising effects of early IGF-1 supplementation on postnatal development and neonatal outcomes.

Body composition of children with different gestation time

OBJECTIVES

To examine the differences in body composition between prepubescent children, depending on the time of gestation.

METHODS

The study was conducted among children aged 3-10 years. The thickness of 5 (triceps, subscapular, suprailiac, abdominal, calf) skinfolds, mid-upper arm circumference, body height, weight and femur breadth was measured. Sum of 3 skinfolds, Body Mass Index (BMI) and muscle mass were calculated. Gestation time was obtained using a questionnaire.

RESULTS

Children in the short gestation time category were generally characterized by the greatest values of the analyzed characteristics, particularly above the ages of 6-8 years. Femur breadth and muscle mass were similar up to the mentioned age in all of the gestation time categories. BMI and all of the adiposity characteristics, below the age of 6 years, were the greatest in the long gestation time category.

CONCLUSIONS

Results of the present study are important, as excess body mass and adiposity are associated with increased risk of cardiovascular and metabolic abnormalities later in life. Special emphasis should be placed on the prevention of overweight and obesity among premature babies and the education of their parents.

Analysis of Factors Associated With Body Mass Index at Ages 18 and 36 Months Among Infants Born Extremely Preterm

IMPORTANCE

The development of neonatology has been associated with improved survival among infants born extremely preterm, and understanding their long-term outcomes is becoming increasingly important. However, there is little information on body mass index (BMI) among these children.

OBJECTIVE

To determine factors associated with BMI at ages 18 months and 36 months among infants born extremely preterm.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective, multicenter cohort study was conducted using data from the Neonatal Research Network Japan database for 8838 infants born at gestational ages 23 to 28 weeks with data on BMI at 18 months and 36 months. Data were analyzed from April 2018 through June 2021.

EXPOSURES

BMI and BMI z score at ages 18 months and 36 months were regressed with gestational age, intrauterine growth restriction (IUGR) status, and complications during pregnancy and the neonatal period separately by presence of multiple pregnancy and sex.

MAIN OUTCOMES AND MEASURES

BMI and BMI z score at ages 18 months and 36 months.

RESULTS

Among 16 791 eligible infants born extremely preterm, 8838 infants were included in the analysis. There were 7089 infants born from single pregnancies (mean [SD] gestational age, 26.0 [1.6] weeks; 3769 [53.2%] boys; mean [SD] birth weight, 847 [228] g) and 1749 infants born from multiple pregnancies (mean [SD] gestational age, 26.3 [1.5] weeks; 903 [51.6%] boys; mean [SD] birth weight, 860 [217] g). In single pregnancies, every week of increased gestational age was associated with an increase in BMI of 0.21 (95% CI, 0.17-0.25) among boys and 0.20 (95% CI, 0.15-0.25) among girls at age 18 months and 0.21 (95% CI, 0.18-0.24) among boys and 0.21 (95% CI, 0.18-0.24) among girls at age 36 months. There was an interaction association between gestational age and IUGR among boys at age 36 months, with a decrease in the change associated with gestational age of 0.12 (95% CI, 0.05-0.19). Every week of increased gestational age in single pregnancies was associated with an increase in BMI z score of 0.14 (95% CI, 0.17-0.21) among boys and 0.17 (95% CI, 0.13-0.21) among girls at age 18 months and 0.19 (95% CI, 0.16-0.22) among boys and 0.17 (95% CI, 0.15-0.20) among girls at age 36 months. Among single pregnancies, IUGR was associated with a decrease in BMI among boys (0.59 [95% CI, 0.23-0.95]) and girls (0.75 [95% CI, 0.39-1.11]) and BMI z score among boys 0.85 [95% CI, 0.25-0.95)] and girls (0.67 [95% CI, 0.36-0.97] at age 18 months and BMI among boys (0.44 [95% CI, 0.17-0.18]) and girls (0.84 [95% CI, 0.55-1.12]) and BMI z score among boys (0.46 [95% CI, 0.21-0.71]) and girls (0.77 [95% CI, 0.53-1.01]) at age 36 months. In multiple pregnancies, IUGR was associated with a decrease in BMI z score at age 36 months among boys (0.26 [95% CI, 0.42-0.89]) and girls (0.29 [95% CI, 0.22-0.79]). In single pregnancies intraventricular hemorrhage (IVH) was associated with a decrease in BMI of 0.47 (95% CI, 0.21-0.73) among boys and 0.42 (95% CI, 0.13-0.71) among girls at age 18 months and 0.53 (95% CI, 0.32-0.74) among boys and 0.31 (95% CI, 0.07-0.54) among girls at age 36 months. IVH was associated with a decrease in BMI z score in single pregnancies of 0.63 (95% CI, 0.20-0.41) among boys and 0.35 (95% CI, 0.12-0.60) among girls at age 18 months and 0.53 (95% CI, 0.34-0.71) among boys and 0.30 (95% CI, 0.11-0.50) among girls at age 36 months. Similar associations were seen in multiple pregnancies.

CONCLUSIONS AND RELEVANCE

This study found that gestational age, the presence of IUGR and multiple pregnancy, and IVH complications were associated with infant BMI at ages 18 months and 36 months. These findings suggest that these complicating factors should be considered when setting growth targets and nutrition strategies for infants born extremely preterm.

25 Years of Research in Human Lactation: From Discovery to Translation

Researchers have recently called for human lactation research to be conceptualized as a biological framework where maternal and infant factors impacting human milk, in terms of composition, volume and energy content are studied along with relationships to infant growth, development and health. This approach allows for the development of evidence-based interventions that are more likely to support breastfeeding and lactation in pursuit of global breastfeeding goals. Here we summarize the seminal findings of our research programme using a biological systems approach traversing breast anatomy, milk secretion, physiology of milk removal with respect to breastfeeding and expression, milk composition and infant intake, and infant gastric emptying, culminating in the exploration of relationships with infant growth, development of body composition, and health. This approach has allowed the translation of the findings with respect to education, and clinical practice. It also sets a foundation for improved study design for future investigations in human lactation.

Early weight gain trajectories and body composition in infancy in infants born very preterm

BACKGROUND

Concerns are raised about the influence of rapid growth on excessive fat mass (FM) gain in early life and later cardiometabolic health of infants born preterm.

OBJECTIVES

To study the association between postnatal weight gain trajectories and body composition in infancy in infants born very preterm.

METHODS

In infants born <30 weeks gestation, we evaluated associations between weight Z-score trajectories for three consecutive timeframes (NICU stay, level-II hospital stay and at home) and body composition, measured at 2 and 6 months corrected age by air-displacement plethysmography.

RESULTS

Of 120 infants included, median gestational age at birth was 27⁺⁵ (interquartile range 26⁺¹ ;28⁺⁵ ) and birth weight 1015 g (801;1250). The majority of infants did not make up for their initial loss of weight Z-score, but growth and later body composition were within term reference values. Weight gain during NICU stay was not associated with fat mass (absolute, %FM or FM index) in infancy. Weight gain during NICU and level II hospital stay was weakly associated with higher absolute lean mass (LM), but not after adjustment for length (LM index). Weight gain in the level-II hospital was positively associated with fat mass parameters at 2 months but not at 6 months. Strongest associations were found between weight gain at home and body composition (at both time points), especially fat mass.

CONCLUSIONS

Weight gain in different timeframes after preterm birth is associated with distinct parameters of body composition in infancy, with weight gain at home being most strongly related to fat mass.

Weight for length measures may not accurately reflect adiposity in preterm infants born appropriate for gestational age during hospitalisation or after discharge from the neonatal intensive care unit

BACKGROUND

Weight/length (W/L) indices are poor surrogates for adiposity in preterm infants born appropriate for gestational age (AGA) at birth, but whether the association subsequently improves is unknown.

OBJECTIVE

To determine if W/L indices accurately reflect adiposity in premature infants born AGA in later infancy.

METHODS

Associations between W/L indices and fat mass, fat mass index and percent body fat (%BF) obtained via air displacement plethysmography (ADP) were examined in 260 preterm infants (majority born AGA) at 28 to 63 weeks' postmenstrual age (PMA). Accuracy of W/L indices as indicators of adiposity was assessed by proportion of variance explained (R² ) and root mean square error from linear regression of adiposity on W/L indices and proportion of infants misclassified by W/L indices. Accuracy was further compared in term vs preterm infants at term-equivalent age. The impact of early vs late preterm status on associations between W/L indices and %BF was also examined.

RESULTS

BMI and W/L were most strongly associated with %BF but yielded poorly fitting models (maximum R² = 0.35; 53% misclassification). A significant interaction of W/L indices and early vs late preterm status on %BF revealed that estimation of %BF differs by status. Accuracy of W/L indices was worse in preterm infants at term-equivalent age.

CONCLUSIONS

W/L indices were not good indicators of adiposity in preterm infants from 28 to 63 weeks' PMA (born AGA) with all categories of W/L indices combined. Future research should examine whether results are similar in preterm infants born with disproportionate W/L or who experience disproportionate growth postnatally.

Body adiposity and oral feeding outcomes in infants: a pilot study

BACKGROUND

Prevalence of oral feeding difficulties in high-risk infants is increasing. Desire to take orally can be influenced by hunger and satiety, which may influence growth and body fat.

OBJECTIVE

To determine the association between body adiposity and infant oral feeding.

METHODS

Retrospective case-control study of infants ≥37-week postmenstrual age (PMA). Infants on tube feeding (cases) compared to birth gestation-matched infants on full oral feeding (controls). Body composition was determined by air displacement plethysmography.

RESULTS

Overall, 16 cases vs. 16 controls. At study, cases vs. controls had similar PMA, weight and length z-scores, and calorie intake. The mean oral intake was significantly less in cases vs. controls (66 vs. 168 ml/kg/day, p < 0.001). Cases had significantly higher percentage of fat mass (18.7 vs. 10.9) and fat-mass z-score (1.62 vs. 0.08) (p < 0.05), but similar fat-free mass vs. controls. Five case infants required gastrostomy.

CONCLUSIONS

Higher body adiposity may worsen the infant oral feeding outcomes.

Infant body composition assessment in the neonatal intensive care unit (NICU) using air displacement plethysmography: Strategies for implementation into clinical workflow

Nutritional management is integral to infant care in the neonatal intensive care unit (NICU). Recent research on body composition that specifically evaluated fat and fat-free mass has improved our understanding of infant growth and nutritional requirements. The need for body composition monitoring in infants is increasingly recognized as changes in fat mass and fat-free mass associated with early growth can impact clinical outcomes. With the availability of air displacement plethysmography (ADP) as a noninvasive method for assessing infant body composition and published normative gestational age- and sex-specific body composition curves, it is justifiable to integrate this innovation into routine clinical care. Here we describe our experiences in implementing body composition measurement using ADP in routine clinical care in different NICU settings.

Associations of early nutrition with growth and body composition in very preterm infants: a prospective cohort study

BACKGROUND/OBJECTIVE

To investigate impacts of early postnatal macronutrient intakes on growth and body composition of preterm infants within the first 6 months.

SUBJECTS/METHODS

One hundred and thirty-three very preterm (VPT) and/or very low birth weight (VLBW) infants were consecutively included. Enteral and parenteral macronutrient intakes during the first 28 days were recorded and average daily intakes were calculated. Growth was measured at birth, term age, and 6 months of corrected age (CA). Body composition was examined by air displacement plethysmograph at term age and 6 months of CA. Associations of nutrient intakes with growth and body composition over time were analyzed using generalized estimating equation.

RESULTS

After adjusting for covariates, higher daily protein, lipid, and energy intake during the first 28 days was associated with higher weight at term age for every 1 g/kg/day increment of protein and lipid intake, and every 10 kcal/kg/day increment of energy intake was associated with 0.50 (95% CI 0.04, 0.96), 0.29 (95% CI 0.07, 0.51), and 0.27 (95% CI 0.10, 0.44) higher weight z-score, respectively. Higher protein intake was associated with lower z-score of fat mass (FM, β = -1.88, 95% CI -3.53, -0.23) and percentage of body fat (PBF, β = -2.18, 95% CI -3.98, -0.39) at 6 months of CA, but higher lipid and carbohydrate intake was associated with higher FM and PBF z-scores at 6 months of CA.

CONCLUSIONS

Macronutrient intakes during the first month of life have impacts on growth and body composition before 6 months of age. Higher daily protein intake is associated with a better growth and healthier body composition for VPT/VLBW infants.

Body composition during the first 4 months in infants affected by neonatal abstinence syndrome: a pilot study

Newborns with neonatal abstinence syndrome (NAS) display symptoms related to neurologic excitability and autonomic dysfunction that result in increased metabolic demands. These infants also exhibit feeding difficulties and/or hyperphagia. Because the effects of these symptoms and behaviors on growth are unknown, we sought to measure serial body composition measurements over the first 4 months in infants with NAS requiring pharmacologic treatment using air displacement plethysmography. Fourteen infants of singleton birth with appropriate-for-gestational-age (AGA) weight and a gestational age of ≥35 weeks and <42 weeks were evaluated. In mixed-effects models, per week, infants increased in mean fat percent by 1.1% (95% confidence interval [CI]: 0.85-1.43), fat mass by 90 g (CI: 70-100), and fat-free mass by 140 g (CI: 130-150). The subgroup of infants (N = 5) requiring multidrug therapy for symptom control had lower mean fat percent (-1.2%, CI: -5.2-2.1), fat mass (-60 g, CI: -25-13), and fat-free mass (-270 g, CI: -610-80) across time compared to infants requiring monotherapy. We are the first to report how body composition measures change over time in a small group of patients with NAS. Infants with NAS were smaller and leaner in the first several weeks compared to previously reported body composition measurements in term infants, but grew similarly to their healthy counterparts by 16 weeks. Infants with more severe NAS may be at risk for abnormalities in longer term growth.

Effect of Preterm Birth on the Risk of Adverse Perinatal and Neonatal Outcomes in Ethiopia: A Systematic Review and Meta-Analysis

Despite remarkable progress in the reduction of under-five mortality, the rate of perinatal and neonatal mortality is still high especially in developing countries. The adverse outcome associated with preterm birth is one of the major public health challenges in Africa. However, there are limited and inconsistent studies conducted on the effect of preterm birth on adverse perinatal and neonatal outcomes in Ethiopia. Therefore, this systematic review and meta-analysis aimed to investigate the association between preterm birth and its adverse perinatal and neonatal outcomes in Ethiopia. We systematically searched several electronic databases like PubMed, Web of Science, SCOPUS, CINAHL, Google Scholar, African Journals Online databases and Science Direct. All identified observational studies were included. The I1 statistics were used to assess the heterogeneity among the studies. A random-effects model was computed to estimate the pooled effect of preterm birth on adverse perinatal and neonatal outcomes. Thirty-three studies with a total of 20 109 live births were included in the final meta-analysis. Our meta-analysis showed that preterm birth increased the odds of perinatal mortality by 10-folds [POR = 9.56 (95% CI: 5.47, 19.69)] and there was a 5.44-folds risk of stillbirth [Odds Ratio = 5.44 (95% CI: 3.57, 8.28)] among women who gave birth before 37 weeks of gestation. In addition, preterm birth was significantly associated with neonatal hypothermia [OR=3.54 (95% CI: 2.41, 5.21)], neonatal mortality [OR= 3.16 (95% CI: 1.57, 6.34). The sub-group analysis of this meta-analysis showed that there was an increased risk of neonatal sepsis [OR=2.33 (95% CI: 1.15, 4.71)] among preterm babies. Preterm births significantly increased the risk of adverse perinatal and neonatal outcomes in Ethiopia. Therefore, scale-up strategies and improving the quality of maternal and child health care providers should be an area of intervention to reduce adverse outcomes associated with preterm birth. The Federal Ministry of Health and concerned bodies should work towards the prevention of preterm birth and its adverse outcomes.

Serial assessment of fat and fat-free mass accretion in very preterm infants: a randomized trial

BACKGROUND

Clinicians could modify dietary interventions during early infancy by monitoring fat and fat-free mass accretion in very preterm infants.

METHODS

Preterm infants were randomly assigned to either having reports on infant body composition available to the clinicians caring for them (intervention group) or not having reports available (control group). All infants underwent serial assessments of body composition by air-displacement plethysmography before 32 weeks of postmenstrual age (PMA) and at 36 weeks PMA. The primary outcome was percent body fat (%BF) at 3 months of corrected age (CA).

RESULTS

Fifty infants were randomized (median gestational age: 30 weeks; mean ± SD birth weight: 1387 ± 283 g). The mean %BF increased from 7 ± 4 before 32 weeks PMA to 20 ± 5 at 3 months CA. The differences in mean %BF between the intervention group and the control group were not statistically significant at 36 weeks PMA (14.5 vs. 13.6) or 3 months CA (20.8 vs. 19.4). Feeding practices and anthropometric measurements during hospitalization did not differ between groups.

CONCLUSIONS

Serial assessments of body composition in both intervention and control groups showed consistent increments in %BF. However, providing this information to clinicians did not influence nutritional practices or growth.

IMPACT

Serial assessments of body composition in preterm infants at 32 and 36 weeks postmenstrual age show consistent increments in % body fat up to 3 months of corrected age. However, providing this information to the clinician did not influence nutritional practices or growth.

Adipose Tissue Development and Expansion from the Womb to Adolescence: An Overview

Prevalence rates of pediatric obesity continue to rise worldwide. Adipose tissue (AT) development and expansion initiate in the fetus and extend throughout the lifespan. This paper presents an overview of the AT developmental trajectories from the intrauterine period to adolescence; factors determining adiposity expansion are also discussed. The greatest fetal increases in AT were observed in the third pregnancy trimester, with growing evidence suggesting that maternal health and nutrition, toxin exposure, and genetic defects impact AT development. From birth up to six months, healthy term newborns experience steep increases in AT; but a subsequent reduction in AT is observed during infancy. Important determinants of AT in infancy identified in this review included feeding practices and factors shaping the gut microbiome. Low AT accrual rates are maintained up to puberty onset, at which time, the pattern of adiposity expansion becomes sex dependent. As girls experience rapid increases and boys experience decreases in AT, sexual dimorphism in hormone secretion can be considered the main contributor for changes. Eating patterns/behaviors and interactions between dietary components, gut microbiome, and immune cells also influence AT expansion. Despite the plasticity of this tissue, substantial evidence supports that adiposity at birth and infancy highly influences its levels across subsequent life stages. Thus, a unique window of opportunity for the prevention and/or slowing down of the predisposition toward obesity, exists from pregnancy through childhood.

NICU Diet, Physical Growth and Nutrient Accretion, and Preterm Infant Brain Development

Half of very preterm infants experience neurodevelopmental impairments after NICU discharge. These adverse outcomes result in part from abnormal brain development and injury that occur during the NICU hospitalization. Although many factors influence infant brain development, nutritional determinants are of particular interest because they are highly modifiable within clinical care. Physical growth of preterm infants in the NICU continues to lag behind the reference fetus, suggesting reduced nutrient accretion during a critical period for brain development. Nutrient accretion is driven by intake of specific nutrients such as macro- and micronutrients as well as non-nutritional factors such as systemic inflammation. Most often, anthropometric indicators, such as weight, length, and head circumference, are used as proxies for nutrient accretion. A limitation of weight is that it does not differentiate the healthy growth of specific organs and tissues from excess fat accumulation. Body length provides information about skeletal growth, and linear growth stunting predicts neurodevelopmental impairment. Head circumference is only a crude proxy for brain size. More recently, application of new technologies such as air displacement plethysmography and magnetic resonance imaging has allowed the direct estimation of lean tissue accretion and brain growth in the NICU. These newer techniques can facilitate research to improve our understanding of the links among the NICU diet, inflammation, physical growth, and brain development. These new measures may also be relevant within clinical care to identify infants who may benefit from specific interventions to enhance nutrient accretion and brain development.

Differential Effect of Growth on Development between AGA and SGA Preterm Infants

Predicting developmental outcomes with growth measurement would be beneficial for primary healthcare or in developing countries with low medical resources. This study aimed to identify physical growth measures that indicate neurodevelopment in very preterm infants. Preterm infants, born at <32 weeks’ gestation or weighing <1500 g, were included. We calculated the changes in z-score of weight, length, and head circumference (HC) at different time points: birth, postmenstrual age (PMA) 35 weeks, and 4 and 18 months corrected age (CA). We examined the relationship between growth and Bayley-III scores using linear regression. Among 122 infants, HC at 4 months CA and HC growth between PMA 35 weeks and 4 months CA showed a positive correlation with Bayley-III scores in appropriate-for-gestational-age infants (AGAs). Weight and length increases between birth and 18 months CA were also associated with AGAs’ development. In small-for-gestational-age infants (SGAs), only birthweight’s z-score was associated with improved neurodevelopmental outcomes. HC at 4 months CA was an important indicator of favorable neurodevelopmental outcomes, and head growth spurt between PMA 35 weeks and 4 months CA contributed to this benefit in preterm AGAs. The period and indices should be monitored differently for SGAs and AGAs.

Premature birth was not associated with increased body fatness in four-year-old boys and girls

AIM

Premature birth is a worldwide problem and increases the risk of chronic disease later in life. Prematurely born infants may have a high percentage of body fat at term-equivalent age, but it is unclear if this characteristic is maintained in childhood. Therefore, we compared the size and body composition of four-year-old prematurely born children to such values of full-term controls.

METHODS

Between 2013 and 2015, we assessed weight, height, fat mass and fat-free mass, using air displacement plethysmography in 188 reasonably healthy prematurely born four-year-olds (98 boys).

RESULTS

At four years of age, prematurely born children (gestational weeks at birth: 23.3-36.9) tended to be lighter and shorter and to contain less fat mass and fat-free mass than did full-term controls. The gestational age at birth of the prematurely born children correlated positively and significantly (P < .05) with height, weight, body mass index, fat mass (kg, %), fat mass index and fat-free mass (kg) in girls but not in boys.

CONCLUSION

Prematurity was not associated with increased body fatness in our four-year-olds. Our findings are relevant in relation to previously published results showing that premature birth is associated with chronic disease later in life.

Nutrition, Illness and Body Composition in Very Low Birth Weight Preterm Infants: Implications for Nutritional Management and Neurocognitive Outcomes

Preterm infants have altered body composition compared to term infants, which impacts both neurodevelopment and metabolic health, but whether increased dietary intake during hospitalization, independent of illness, may improve body composition is unknown. This prospective, longitudinal study (n = 103) measured fat-free mass (FFM) and percent body fat (%BF) at discharge and four months corrected age for prematurity (CA) in very low birth weight (VLBW) preterm infants. Markers of illness and macronutrient intakes (protein and caloric) were recorded. Bayley Scales of Infant Development-III (BSID) were administered at 12 and 24 months of age in a subset of these infants (n = 66 and n = 50 respectively). Body composition z-scores were calculated using recently developed reference curves. Linear regression was used to test the associations between clinical factors and body composition z-scores, as well as z-scores and BSID scores. Increased calories and protein received in the first week after birth and protein intake throughout hospitalization were associated with increased FFM z-scores at discharge, but not with %BF z-scores. After adjustment for both early acute and chronic illness, associations of nutrient intake with FFM z-score remained unchanged. FFM z-scores at discharge were positively associated with scores on the BSID at 12 and 24 months CA. In conclusion, increased energy and protein intakes both early in hospitalization and across its entire duration are associated with higher FFM at discharge, a key marker for organ growth and neurodevelopment in the VLBW neonate. Optimizing caloric intake, irrespective of illness is critical for enhancing body composition, and by extension, neurodevelopmental outcomes for preterm infants.

Lean Tissue Deficit in Preterm Infants Persists up to 4 Months of Age: Results from a Swedish Longitudinal Study

BACKGROUND

At term-equivalent age, infants born prematurely are shorter, lighter and have more adipose tissue compared to term counterparts. Little is known on whether the differences in body composition persist in later age.

METHODS

We prospectively recruited 33 preterm infants (<32 weeks gestational age, mean gestational age 28.1 weeks) and 69 term controls. Anthropometry and body composition (air displacement plethysmography) were monitored up to 4 months of age. Nutrient intakes from preterm infants were collected from clinical records.

RESULTS

At 4 months of age preterm infants were lighter and shorter than term controls (mean weight-for-age z-score: -0.73 vs. 0.06, p = 0.001; mean length-for-age z-score: -1.31 vs. 0.29, p < 0.0001). The significantly greater percentage of total body fat seen in preterm infants at term-equivalent age (20.2 vs. 11.7%, p < 0.0001) was no longer observed at 4 months. A deficit of fat-free mass persisted until 4 months of age (fat-free mass at term-equivalent age: 2.71 vs. 3.18 kg, p < 0.0001; at 4 months: 4.3 vs. 4.78 kg, p < 0.0001). The fat mass index and fat-free mass index (taking length into account) did not differ between the groups. Nutrition had little effect on body composition. Higher protein intake at week 2 was a negative predictor of fat-free mass at discharge.

CONCLUSIONS

At 4 months corrected age, preterm infants were both lighter and shorter than term controls and the absolute fat-free mass deficit remained until this age. Little effect of nutrition on body composition was observed.

Neonatal body composition by air displacement plethysmography in healthy term singletons: a systematic review

BACKGROUND

There is increasing evidence that intrauterine environment and, consequently, growth in utero have both immediate and far-reaching consequences for health. Neonatal body composition might be a more sensitive marker of intrauterine environment and neonatal adiposity than birth weight and could serve as a predictor for non-communicable diseases later in life.

METHODS

To perform a systematic literature review on neonatal body composition determined by air displacement plethysmography in healthy infants. The systematic review was performed using the search terms "air displacement plethysmography", "infant" and "newborn" in Pubmed. Data are displayed as mean (Standard deviation).

RESULTS

Fourteen studies (including n = 6231 infants) using air displacement plethysmography fulfilled inclusion criteria for meta-analysis. In these, weighted mean body fat percentage was 10.0 (4.1) % and weighted mean fat free mass was 2883 (356) g in healthy term infants. Female infants had a higher body fat percentage (11.1 (4.1) % vs. 9.6 (4.0) %) and lower fat free mass (2827 (316) g vs. 2979 (344) g). In the Caucasian subpopulation (n = 2202 infants) mean body fat percentage was 10.8 (4.1), whereas data for reference values of other ethnic groups are still sparse.

CONCLUSIONS

Body composition varies depending on gender and ethnicity. These aggregated data may serve as reference for body composition in healthy, term, singletons at least for the Caucasian subpopulation.

Exposure to placental insufficiency alters postnatal growth trajectory in extremely low birth weight infants

Growth in the immediate postnatal period for extremely low birth weight (ELBW, birth weight < 1000 g) infants is an important topic in neonatal medicine. The goal is to ensure adequate postnatal growth and to minimize complications resulting from suboptimal growth. Past efforts have focused on postnatal nutrition as well as on minimizing comorbidities. It has not been systematically assessed whether antenatal factors play a role in postnatal growth. In this report, we conducted a retrospective study on 91 maternal-neonatal pairs. We prospectively collected maternal and neonatal demographic data, neonatal nutrition in the first 7 days of life and after enteral nutrition is fully established, comorbidity data, as well as weight data from birth to 50 weeks corrected gestational age. We developed a linear mixed-effects model to examine the role of placental insufficiency, as defined by fetal Doppler studies, in postnatal weight z-score trajectory over time in the ELBW population. We relied on Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC) for model selection. Interestingly, the selected model included a quadratic term of time and a placental insufficiency-by-time interaction term. In a covariate analysis, AIC and BIC both favored a model that included calories intake in the first 7 days of life and the total duration of antibiotics as fixed-effects, but not their interaction terms with time. Overall, we demonstrated for the first time that placental insufficiency, an antenatal factor, is a major determinant of postnatal weight trajectory in the ELBW population. Prospective studies are warranted to confirm our findings.

Relations among maternal physical activity during pregnancy and child body composition

OBJECTIVE

Physical activity (PA) during pregnancy is associated with lower neonatal fat mass, but associations with child body composition are mixed. The purpose of this study was to examine associations between trimester-specific pregnancy PA and child body composition at 4 years.

METHODS

Participants of the Minnesota Infant Nutrition, Neurodevelopment, and Obesity Study were asked to recall participation in any moderate or vigorous PA in the first (T1), second (T2) and third (T3) trimesters at about 5 years postpartum. Child fat mass and fat-free mass were measured via air displacement plethysmography at 2 weeks, 3 months and 4 years of age. Multivariate linear regression was used for analyses.

RESULTS

Of 51 possible participants, 37 recalled pregnancy PA. Any vigorous PA in T3 was associated with lower child fat mass at 4 years (adjβ = -1.077, p < 0.05).

CONCLUSION

Late pregnancy PA may have lasting benefits for child body composition. Replication of these findings is needed in a larger sample with prospective measures.

Factors affecting body composition in preterm infants: Assessment techniques and nutritional interventions

Limited research has been conducted that elucidates the growth and body composition of preterm infants. It is known that these infants do not necessarily achieve extra-utero growth rates and body composition similar to those of their term counterparts. Preterm infants, who have difficulty in achieving these growth rates, could suffer from growth failure. These infants display an increased intra-abdominal adiposity and abnormal body composition when they achieve catch-up growth. These factors affect the quality of weight gain, as these infants are not only shorter and lighter than term infants, they also have more fat mass (FM) and less fat-free mass (FFM), resulting in a higher total fat percentage. This could cause metabolic syndrome and cardiovascular problems to develop later in a preterm infant's life. The methods used to determine body composition in preterm infants should be simple, quick, non-invasive and inexpensive. Available literature was reviewed and the Dauncey anthropometric model, which includes skinfold thickness at two primary sites and nine body dimensions, is considered in this review the best method to accurately determine body composition in preterm infants, especially in resource-poor countries. It is imperative to accurately assess the quality of growth and body composition of this fragile population in order to determine whether currently prescribed nutritional interventions are beneficial to the overall nutritional status and quality of life-in the short- and long-term-of the preterm infant, and to enable timely implementation of appropriate interventions, if required.

Body composition and cognition in preschool-age children with congenital gastrointestinal anomalies

BACKGROUND

Children with congenital gastrointestinal anomalies (CGIAs) experience multiple stressors while hospitalized in neonatal intensive care units during an essential time of growth and development. Early stress and inadequate nutrition are linked to altered growth patterns and later neurodevelopmental delays. In other at-risk populations, improved fat-free mass (FFM) accretion is associated with improved cognitive outcomes.

OBJECTIVE

To determine if body composition is associated with cognitive function in preschool-age children with CGIAs.

STUDY DESIGN

An observational study examined body composition and cognition in 34 preschool-age children with CGIAs. Anthropometric measurements and body composition testing via air displacement plethysmography were obtained. Measurements were compared with a reference group of healthy, term-born children. Cognition was measured with the NIH Toolbox Early Childhood Cognition Battery. Linear regression was used to test the association of body composition with cognitive function.

RESULTS

Compared with the reference group, children with CGIAs had similar anthropometric measurements (weight, height, and body mass index z-scores) and body composition at preschool-age. Processing speed scores were lower than standardized means (p = 0.001). Increased FFM was associated with higher receptive vocabulary scores (p = 0.001), cognitive flexibility scores (p = 0.005), and general cognitive function scores (p = 0.05).

CONCLUSIONS

At preschool-age, children with CGIAs have similar growth and body composition to their peers. In children with CGIAs, higher FFM was associated with higher cognitive scores. Closer tracking of body composition and interventions aimed at increasing FFM may improve long-term outcomes in this population.

Early body composition changes are associated with neurodevelopmental and metabolic outcomes at 4 years of age in very preterm infants

BACKGROUND

Very preterm (VPT) infants are at-risk for altered growth, slower speed of processing (SOP), and hypertension. This study assesses the relationship between postnatal body composition (BC), neurodevelopment (indexed by SOP), and blood pressure (BP) in VPT infants.

METHODS

Thirty-four VPT infants underwent weekly measurements and BC testing until discharge and post-discharge at 4 mos CGA and 4 yrs. At post-discharge visits, SOP was assessed using visual evoked potentials and the NIH Toolbox; BP was also measured.

RESULTS

In-hospital rate of weight, length and fat-free mass (FFM) gains were associated with faster SOP at 4 yrs. Higher rate of gains in weight and FFM from discharge to 4 mos CGA were associated with faster SOP at 4 mos CGA, while higher fat mass (FM) gains during the same time were positively associated with BP at 4 yrs. BC at 4 yrs nor gains beyond 4 mos CGA were associated with outcomes.

CONCLUSIONS

In VPT infants, early FFM gains are associated with faster SOP, whereas post-discharge FM gains are associated with higher BPs at 4 yrs. This shows birth to 4 mos CGA is a sensitive period for growth and its relation to neurodevelopmental and metabolic outcomes. Close monitoring and early nutritional adjustments to optimize quality of gains may improve outcomes.

Effect of standardized feeding protocol on nutrient supply and postnatal growth of preterm infants: A prospective study

BACKGROUND

Preterm birth is a medical emergency and it is becoming evident that adequate nutrition starting in the first hours of life is of major importance for short and even more so for long-term health outcomes of the premature newborn. The aim was to analyze postnatal nutrient supply and growth patterns of preterm infants in response to a standardized feeding protocol during stay at neonatal intensive care unit (NICU).

METHODS

A prospective cohort study was conducted at NICU, Children Hospital Graz. Infants were divided in two groups:<28 weeks (Extremely preterm infants, EPI); ≥28 weeks (very preterm infants, VPI).

RESULTS

EPI compared to VPI stayed longer on parenteral nutrition and needed more time to reach full enteral nutrition, required more days on ventilation and had a higher corrected age at discharge. Moreover, fortification of enteral feeds was initiated later in EPI group (p < 0.001). As a consequence, cumulative supply of protein, fat and energy was significantly lower in EPI. However, both groups exceeded the European Society of Gastroenterology, Hepatology and Nutrition (ESPGHAN) recommended glucose intake in week 5. At discharge, we found significant differences in all growth parameters (weight Z scores: EPI = - 1.19 vs VPI = - 0.71, length Z scores: EPI = - 1.62 vs VPI = - 0.84; HC Z scores: EPI = - 1.19 vs VPI = - 0.46).

CONCLUSIONS

Provision of aggressive parenteral nutrition during first 3 weeks of life and earlier fortification should be ensured. The use of mother milk fortifier resulted in glucose intake above the ESPGHAN recommendations in later weeks - this needs to be evaluated in future studies.

Leptin and IGF-1 in relation to body composition and bone mineralization of preterm-born children from infancy to 8 years

OBJECTIVE

Preterm birth has been associated with altered body composition, especially increased fat mass (FM) and decreased bone mineralization, and leptin and IGF-1 have been suggested to be involved in the regulation of both. We aimed to study the interplay between leptin, IGF-1, FM and bone mineralization measured in infancy and childhood of children born preterm.

DESIGN

Observational study.

PATIENTS/SUBJECTS

Seventy-nine (40 boys) preterm-born children (gestational age ≤32 weeks and/or birth weight ≤1500 g) aged 8 years.

MEASUREMENTS

Serum leptin and IGF-1 were measured at term age, at 3- and 6-month corrected age (CA), and 8 years. Body composition (fat and lean mass) and bone parameters (bone area, mineral content and density) were measured by Dual-energy X-ray Absorptiometry (DXA) at term age, 6-month CA and 8 years.

RESULTS

Leptin was positively associated with FM at all time points and with bone parameters at term age and 6-month CA. IGF-1 was associated with body composition and bone density at most of the time points. Explained variation in bone mineralization increased significantly by adding bone area (BA) and height to the models.

CONCLUSIONS

During infancy and childhood, leptin and IGF-1 were associated with body composition in preterm-born children. In addition, leptin was associated with bone parameters in early infancy, but not in childhood. It is hypothesized that a complicated interplay between multiple pathways, which most likely changes over time, is involved in regulation of body composition and bone mineralization of preterm-born infants.

Air displacement plethysmography (pea pod) in full-term and pre-term infants: a comprehensive review of accuracy, reproducibility, and practical challenges

Air displacement plethysmography (ADP) has been widely utilised to track body composition because it is considered to be practical, reliable, and valid. Pea Pod is the infant version of ADP that accommodates infants up to the age of 6 months and has been widely utilised to assess the body composition of full-term infants, and more recently pre-term infants. The primary goal of this comprehensive review is to 1) discuss the accuracy/reproducibility of Pea Pod in both full- and pre-term infants, 2) highlight and discuss practical challenges and potential sources of measurement errors in relation to Pea Pod operating principles, and 3) make suggestions for future research direction to overcome the identified limitations.

Statewide Initiative to Reduce Postnatal Growth Restriction among Infants <31 Weeks of Gestation

OBJECTIVE

To decrease the incidence of postnatal growth restriction, defined as discharge weight <10th percentile for postmenstrual age, among preterm infants cared for in New York State Regional Perinatal Centers.

STUDY DESIGN

The quality improvement cohort consisted of infants <31 weeks of gestation admitted to a New York State Regional Perinatal Center within 48 hours of birth who survived to hospital discharge. Using quality improvement principles from the Institute for Healthcare Improvement and experience derived from successfully reducing central line-associated blood stream infections statewide, the New York State Perinatal Quality Collaborative sought to improve neonatal growth by adopting better nutritional practices identified through literature review and collaborative learning. New York State Regional Perinatal Center neonatologists were surveyed to characterize practice changes during the project. The primary outcome-the incidence of postnatal growth restriction-was compared across the study period from baseline (2010) to the final (2013) years of the project. Secondary outcomes included differences in z-score between birth and discharge weights and head circumferences.

RESULTS

We achieved a 19% reduction, from 32.6% to 26.3%, in postnatal growth restriction before hospital discharge. Reductions in the difference in z-score between birth and discharge weights were significant, and differences in z-score between birth and discharge head circumference approached significance. In survey data, regional perinatal center neonatologists targeted change in initiation of feedings, earlier breast milk fortification, and evaluation of feeding tolerance.

CONCLUSIONS

Statewide collaborative quality improvement can achieve significant improvement in neonatal growth outcomes that, in other studies, have been associated with improved neurodevelopment in later infancy.

Parenteral nutrition for preterm infants: Issues and strategy

Due to transient gut immaturity, most very preterm infants receive parenteral nutrition (PN) in the first few weeks of life. Yet providing enough protein and energy to sustain optimal growth in such infants remains a challenge. Extrauterine growth restriction is frequently observed in very preterm infants at the time of discharge from hospital, and has been found to be associated with later impaired neurodevelopment. A few recent randomized trials suggest that intensified PN can improve early growth; whether or not such early PN improves long-term neurological outcome is still unclear. Several other questions regarding what is optimal PN for very preterm infants remain unanswered. Amino acid mixtures designed for infants contain large amounts of branched-chain amino acids and taurine, but there is no consensus on the need for some nonessential amino acids such as glutamine, arginine, and cysteine. Whether excess growth in the first few weeks of life, at a time when very preterm infants receive PN, has an imprinting effect, increasing the risk of metabolic or vascular disease at adulthood continues to be debated. Even though uncertainty remains regarding the long-term effect of early PN, it appears reasonable to propose intensified initial PN. The aim of the current position paper is to review the evidence supporting such a strategy with regards to the early phase of nutrition, which is mainly covered by parenteral nutrition. More randomized trials are, however, needed to further support this type of approach and to demonstrate that this strategy improves short- and long-term outcome.

The Energy Costs of Prematurity and the Neonatal Intensive Care Unit (NICU) Experience

Premature neonates are in an energy deficient state due to (1) oxygen desaturation and hypoxia events, (2) painful and stressful stimuli, (3) illness, and (4) neurodevelopmental energy requirements. Failure to correct energy deficiency in premature infants may lead to adverse effects such as neurodevelopmental delay and negative long-term metabolic and cardiovascular outcomes. The effects of energy dysregulation and the challenges that clinicians in the Neonatal Intensive Care Unit (NICU) face in meeting the premature infant's metabolic demands are discussed. Specifically, the focus is on the effects of pain and stress on energy homeostasis. Energy deficiency is a complex problem and requires a multi-faceted solution to promote optimum development of premature infants.

Is the body composition development in premature infants associated with a distinctive nuclear magnetic resonance metabolomic profiling of urine?

OBJECTIVE

Preterm infants' body composition at term-corrected age differs from that of term infants but appears to be similar at the age of 3 months. The aim of this study was to compare the metabolomic pattern of preterm infants at term and at 3 months with that of term infants and to determine its association with body composition development.

METHOD

We designed a pilot study. Growth and body composition were evaluated by an air displacement plethysmography system in 13 preterm infants and seven term newborns at term and at 3 months of corrected age. Urine samples were collected at the same time points and analysed by nuclear magnetic resonance.

RESULTS

At term-corrected age, preterm infants showed a higher fat mass percentage compared with that of term newborns, whereas at 3 months of corrected age, the body composition parameters were similar between the groups. At the first time point, nuclear magnetic resonance analysis showed a urinary increase in choline/phosphocholine, betaine and glucose in preterm infants. At the second time point, the preterm group exhibited a urinary increase in choline/phosphocholine and a decrease in betaine.

CONCLUSIONS

The increased urinary excretion of choline, a betaine precursor, could reflect a potential altered metabolism in preterm infants.

Individualized Postnatal Growth Trajectories for Preterm Infants

BACKGROUND

Growth of preterm infants is monitored using fetal charts despite individual trajectories being downshifted postnatally by adaptational processes. The study aims to compare different approaches to create individualized postnatal trajectories.

METHODS

Three approaches to achieve growth similar to healthy term infants at 42+0/7 weeks postmenstrual age (PMA) on World Health Organization growth standards (WHOGS) (target weight) were tested by comparing trajectories obtained by: 1) following birth percentiles (Birth-Weight-Percentile Approach); 2) following percentiles achieved at day of life 21 (Postnatal-Percentile Approach); 3) using day-specific fetal median growth velocities starting at day of life 21 (Fetal-Median-Growth Approach [FMGA]). The primary outcome was delta weight (ΔW), defined as difference between target weight (WHOGS) at 42+0/7 weeks and weight predicted by trajectories. The secondary outcome was ΔW vs %fat mass in a cohort of 20 disease-free surviving very low-birth-weight infants.

RESULTS

Birth-Weight-Percentile and Postnatal-Percentile Approach showed high ΔW; FMGA alone reduced ΔW. Introducing a factor to FMGA to reflect the transition to extrauterine conditions (Growth-Velocity Approach [GVA]) minimized ΔW. GVA merged with target and best normalized for body composition related to ΔW.

CONCLUSIONS

GVA provides an evidence-based approach for individualized growth trajectories. GVA is based on physiologic data and that healthy preterm infants adjust their postnatal trajectory below their birth percentile. GVA may reflect a biologic principle because it matches consistently with WHOGS at 42+0/7 weeks for all preterm infants from 24 to 34 weeks. This concept could become a bedside tool to aid clinicians in monitoring growth, guiding nutrition, and minimizing chronic adult disease risks as a consequence of unguided, inappropriate growth.

Growth and body composition of preterm infants less than or equal to 32 weeks: Cohort study

BACKGROUND

Extremely preterm infants with weights less than the 10th percentile at discharge have a fat-free mass deficit.

AIM

To analyze the relationship of weight Z-scores less than -2SD at term age with fat-free mass and fat mass at term age and at 1 and 3 months of corrected age in very preterm infants.

STUDY DESIGN

COHORT STUDY: Subjects: Sixty-six preterm infants born before or at 32 weeks gestation with birth weight equal or greater than the 10th percentile for age were included at term age. They were classified according to weight Z-score as either: "term (-)" (n = 18) if weight Z-scores were less -2SD or "term (+)" (n = 48) if the weight Z-scores were equal or greater than -2SD at term age.

OUTCOME MEASURES

Growth and body composition by an air displacement plethysmography system and bioimpedance were assessed at term age and 1 and 3 months of corrected age.

RESULTS

Lower fat-free mass persisted up to 3 months in the "term (-)" group [4137 g (645) vs 4592 g (707), p < .01]. Fat mass was lower in the "term (-)" group at term and at 1 month but was similar at 3 months of corrected age [1295 g (774) vs 1477 g (782), p = .109]. Weight, length and head circumference Z-scores were lower in the "term (-)" group compared to those in the "term (+)" group.

CONCLUSIONS

The lean tissue deficits were maintained in the "term (-)" group while the differences in body fat percentage were not.

Body Composition Changes from Infancy to 4 Years and Associations with Early Childhood Cognition in Preterm and Full-Term Children

BACKGROUND

Infants born prematurely are at risk for neurodevelopmental complications. Early growth is associated with improved later cognition. The relationship of early proportionality and body composition with later cognition is not well established.

OBJECTIVES

To assess differences in fat-free mass and adiposity (fat mass, percent body fat) changes in preterm and full-term infants through preschool age and examine associations with early childhood cognition.

METHODS

This is a prospective, observational study in an appropriate for gestational age cohort of 71 patients (20 preterm and 51 full-term) from infancy through preschool age. Anthropometric and body composition measurements via air displacement plethysmography were obtained during infancy at term and 3-4 months (preterm corrected ages), and at 4 years. Cognitive testing occurred at 4 years. Associations of body composition changes between visits with cognitive function were tested using linear regression.

RESULTS

In the preterm group, higher term to 4-month corrected age percent body fat gains were associated with lower working memory performance (p = 0.01), and higher 4-month corrected age to 4-year fat-free mass gains were associated with higher full-scale IQ (p = 0.03) and speed of processing performance (p ≤ 0.02). In the full-term group, higher 4-month to 4-year fat mass gains were associated with lower full-scale IQ (p = 0.03).

CONCLUSIONS

Body composition gains during different time periods are associated with varying areas of cognitive function. These findings may inform interventions aimed at optimal growth.

The impact of intrauterine and extrauterine weight gain in premature infants on later body composition

BackgroundThe impact of intrauterine and extrauterine growth on later insulin resistance and fat mass (FM) in very low birth weight (VLBW) infants is not well established. The aim of our study was to evaluate the effects of intrauterine and early/late extrauterine growth on later insulin resistance and body composition in VLBW infants from 6 months' corrected age (CA) to 36 months.MethodsProspective measurements of body composition by dual-energy X-ray absorptiometry and insulin resistance by homeostasis model assessment insulin resistance (HOMA-IR) along with other fasting plasma biochemistries were made in 95 VLBW infants at 6, 12, 18, and 24 months' CA and 36 months' postnatal age. Mixed-effect models were used to evaluate the effects of age, sex, maturation status, and Δweight SD score on percentage FM (PFM), FM index (FMI), fat-free mass index (FFMI), and HOMA-IR.ResultsPFM and FMI were negatively associated with a decrease in weight-SD scores from birth to 36 weeks' postmenstrual age (PMA; P=0.001) and from 36 weeks' PMA to 6 months' CA (P=0.003). PFM and FMI were higher in AGA than in small for gestational age (SGA) infants. HOMA-IR was not associated with the Δweight-SD scores in either period.ConclusionsCatch-down growth in terms of weight is associated with persistently lower adiposity but not insulin resistance up to 36 months of age.

An observational cohort study of weight- and length-derived anthropometric indicators with body composition at birth and 5 mo: the Healthy Start study

Background: Despite widespread use of weight- and length-based anthropometric indexes as proxies for adiposity, little is known regarding the extent to which they correspond with fat mass (FM) or fat-free mass (FFM) during infancy.Objective: This study aimed to examine associations of 3 derived indicators-weight-for-age z score (WFAZ), weight-for-length score (WFLZ), and body mass index z score (BMIZ)-with FM, percentage of FM, and FFM measured by air-displacement plethysmography during the first 5 mo of life.Design: Applying prospectively collected data from 1027 infants in a Colorado prebirth cohort, we used multivariate regression to evaluate associations between the derived indicators and body composition at birth and at 5 mo, and with change (Δ) during follow-up.Results: At birth, all 3 derived indicators were more strongly associated with FFM than with FM. Each unit of WFAZ corresponded with 0.342 kg FFM (95% CI: 0.331, 0.351 kg FFM), compared with 0.121 kg FM (95% CI: 0.114, 0.128 kg FM) (P < 0.0001); similar trends were observed for WFLZ and BMIZ. By 5 mo, WFLZ and BMIZ were more strongly associated with FM than with FFM, whereas WFAZ correlated similarly with the 2 components of body composition. ΔWFLZ and ΔBMIZ were both more strongly related to ΔFM than to ΔFFM; however, a direct comparison of the 2 indexes with respect to change in the percentage of FM indicated that ΔBMIZ was the optimal proxy of adiposity gain (P < 0.0001, pairwise difference).Conclusions: Weight- and length-based indexes are poor surrogates for newborn adiposity. However, at 5 mo, WFLZ and BMIZ are suitable proxies of FM. When assessing adiposity gain, ΔBMIZ is the best indicator of fat accrual during the first 5 postnatal months. This trial was registered at clinicaltrials.gov as NCT02273297.