Trajectory and correlates of growth of extremely-low-birth-weight adolescents

Association of Growth During Infancy with Neurodevelopment and Obesity in Children Born Very Preterm: The Environmental Influences on Child Health Outcomes Cohort

OBJECTIVE

To evaluate associations between change in weight z score after neonatal intensive care unit (NICU) discharge and neurodevelopmental outcomes and obesity at 12-48 months of age among individuals born very preterm.

STUDY DESIGN

This secondary analysis used data from infants born very preterm participating in the Environmental influences on Child Health Outcomes cohort (n = 1400). Growth during infancy was calculated as change in weight z score between NICU discharge and follow-up at a mean of 27 months of age. Very low weight gain was defined as a change in weight z score <-1.67; very high weight gain was a change in weight z score >1.67. Neurodevelopmental outcomes included the Bayley Scales of Infant and Toddler Development, Child Behavior Checklist 1.5-5 years, and Modified Checklist for Autism in Toddlers. Multivariable linear regression was used to estimate associations between increase in weight z score and neurodevelopmental outcomes.

RESULTS

Very low weight gain between NICU discharge and follow-up (experienced by 6.4% of participants) was associated with lower scores on cognitive (adjusted mean difference: -4.26; 95% CI: -8.55, -0.04) and language (adjusted mean difference: -4.80; 95% CI: -9.70, -0.11) assessments. Very high weight gain (experienced by 13.6% of participants) was associated with an increased obesity risk (adjusted relative risk: 6.20; 95% CI: 3.99, 9.66) but not with neurodevelopmental outcomes.

CONCLUSIONS

Very high weight gain in the first 12-48 months after NICU discharge was associated with a higher risk of obesity at follow-up; very low weight gain was associated with lower scores on cognitive and language assessments.

Postnatal growth in small vulnerable newborns: a longitudinal study of 2 million Brazilians using routine register-based linked data

BACKGROUND

Preterm, low-birth weight (LBW) and small-for-gestational age (SGA) newborns have a higher frequency of adverse health outcomes, including linear and ponderal growth impairment.

OBJECTIVE

To describe the growth trajectories and to estimate catch-up growth during the first 5 y of life of small newborns according to 3 vulnerability phenotypes (preterm, LBW, SGA).

METHODS

Longitudinal study using linked data from the 100 Million Brazilian Cohort baseline, the Brazilian National Live Birth System (SINASC), and the Food and Nutrition Surveillance System (SISVAN) from 2011 to 2017. We estimated the length/height-for-age (L/HAZ) and weight-for-age z-score (WAZ) trajectories from children of 6-59 mo using the linear mixed model for each vulnerable newborn phenotype. Growth velocity for both L/HAZ and WAZ was calculated considering the change (Δ) in the mean z-score between 2 time points. Catch-up growth was defined as a change in z-score > 0.67 at any time during follow-up.

RESULTS

We analyzed 2,021,998 live born children and 8,726,599 observations. The prevalence of at least one of the vulnerable phenotypes was 16.7% and 0.6% were simultaneously preterm, LBW, and SGA. For those born at term, all phenotypes had a period of growth recovery from 12 mo. For preterm infants, the onset of L/HAZ growth recovery started later at 24 mo and the growth trajectories appear to be lower than those born at term, a condition aggravated among children with the 3 phenotypes. Preterm and female infants seem to experience slower growth recovery than those born at term and males. The catch-up growth occurs at 24-59 mo for males preterm: preterm + AGA + NBW (Δ = 0.80), preterm + AGA + LBW (Δ = 0.88), and preterm + SGA + LBW (Δ = 1.08); and among females: term + SGA + NBW (Δ = 0.69), term + AGA + LBW (Δ = 0.72), term + SGA + LBW (Δ = 0.77), preterm + AGA + LBW (Δ = 0.68), and preterm + SGA + LBW (Δ = 0.83).

CONCLUSIONS

Children born preterm seem to reach L/HAZ and WAZ growth trajectories lower than those attained by children born at term, a condition aggravated among the most vulnerable.

Growth During Infancy After Extremely Preterm Birth: Associations with Later Neurodevelopmental and Health Outcomes

OBJECTIVE

To evaluate associations between changes in weight, length, and weight/length ratio during infancy and outcomes later in life among individuals born extremely preterm.

STUDY DESIGN

Among participants in the Extremely Low Gestational Age Newborn (ELGAN) study, we measured weight and length at discharge from the neonatal intensive care unit (NICU) and at age 2 years and evaluated neurocognitive, psychiatric, and health outcomes at age 10 years and 15 years. Using multivariable logistic regression, we estimated associations between gains in weight, length, and weight/length ratio z-scores between discharge and 2 years and outcomes at 10 and 15 years. High gain was defined as the top quintile of change; low gain, as the bottom quintile of change.

RESULTS

High gains in weight and weight/length were associated with greater odds of obesity at 10 years, but not at 15 years. These associations were found only for females. High gain in length z-score was associated with lower odds of obesity at 15 years. The only association found between high gains in growth measures and more favorable neurocognitive or psychiatric outcomes was between high gain in weight/length and lower odds of cognitive impairment at age 10 years.

CONCLUSIONS

During the 2 years after NICU discharge, females born extremely preterm with high gains in weight/length or weight have greater odds of obesity at 10 years, but not at 15 years. Infants with high growth gains in the 2 years after NICU discharge have neurocognitive and psychiatric outcomes in middle childhood and adolescence similar to those of infants with lower gains in weight and weight/length.

Growth Patterns of Children With Short Stature in Adulthood According to Auxological Status and Maturity at Birth

CONTEXT

Prematurity carries a risk for impaired postnatal growth and long-term growth restriction. Especially children born SGA seem vulnerable for poor growth, as a persistent short stature can be observed in app 10-15% of these children.

OBJECTIVE

In this study we aimed to recognize differences in growth patterns of children according to sex, maturity, and auxological status at birth facilitating earlier identification of small-for-gestational-age (SGA) children with adult short stature.

METHODS

The growth data of 44 791 infants born between January 1, 1980, and December 30, 2012, among 2 pediatric cohorts with follow-up through December 31, 2020, were analyzed. A total of 5698 children with birth data had measurements at near final height (nfh) and at least 2 further points.

RESULTS

Preterm children (gestational age < 37 weeks) had a significantly lower mean nfh SDS than term children (preterm, -0.61; term, -0.18) and a higher likelihood of nfh < third percentile (preterm, 20.5%; term, 12.2%). SGA born children also had a lower mean nfh SD score (SDS) than children born appropriate for gestational age (AGA) (SGA, -1.06; AGA, -0.15) and a higher likelihood of nfh < third percentile (SGA, 28.2%; AGA 10.1%). Of 1204 SGA children, 672 (56%) showed successful catch-up growth (CUG) to nfh greater than or equal to the 10th percentile (SGA-CU), and 532 children (44%) did not (SGA-S). The difference in their mean nfh SDS (SGA-CU, -0.12; SGA-S -2.26) can only partly be explained by the differences in mean mid-parental height SDS (SGA-CU, -0.3; SGA-S, -1.19). During the first year, SGA-CU showed higher CUG (SGA-CU, +1.2 SDS; SGA-S, +0.45 SDS), which helps to discriminate between groups earlier.

CONCLUSION

Final growth outcome was influenced by prematurity and auxological status at birth, but not by sex. Height/length SDS increments during year 1 are instrumental to discern SGA children with later normal or short stature. While observing CUG until year 2 and 3 can add specificity, discrimination thereafter becomes difficult.

Pre-pregnancy body mass index, gestational weight gain and postnatal growth in preterm infants

OBJECTIVE

To evaluate associations between pre-pregnancy body mass index (BMI), gestational weight gain (GWG), and postnatal growth in preterm infants.

DESIGN

A cohort study of 14,962 births < 32 weeks' gestation. We used multivariable linear regression to assess associations between maternal BMI or GWG (models stratified by BMI) and infant postnatal growth, defined as the difference between discharge and birth weight Z-scores based on Fenton or INTERGROWTH-21st growth charts.

RESULT

For BMI, obesity class 2 was positively associated with postnatal growth using the Fenton chart. Using INTERGROWTH-21st, inadequate or excessive GWG in women with underweight or obesity class 3 were associated with postnatal growth in different directions. Excessive GWG in women with normal weight was negatively associated with postnatal growth defined by Fenton.

CONCLUSION

Some categories of BMI and GWG were modestly associated with postnatal growth in preterm infants. Results were inconsistent within and between the INTERGROWTH-21st standard and Fenton growth reference.

Temperament, socioeconomic adversity, and perinatal risk as related to preschoolers' BMI

OBJECTIVE

Disparities in childhood obesity necessitate identification of risk-protective and risk- augmenting factors for young children experiencing socioeconomic adversity born with perinatal risk. Temperamental reactivity is a biological marker of susceptibility to environmental characteristics. This study tested whether temperamental reactivity moderated the relation between socioeconomic risk and children's body mass index (BMI).

METHOD

This study examined 100 Head Start preschoolers (Mage = 4.07 years, SD = 0.56) with perinatal risk, defined as preterm birth (PT, <37 weeks gestation) or low birth weight (LBW, <2500g). Anthropometric measurements were collected from children and parents. Parents completed questionnaires on family level demographics and household food insecurity to create a cumulative socioeconomic risk variable. Parents also completed the Children's Behavior Questionnaire to assess preschoolers' temperamental reactivity.

RESULTS

Results supported a differential susceptibility hypothesis such that preschoolers' temperamental reactivity significantly moderated the relation between socioeconomic risk and child BMI z-score (BMIz). Higher BMIz was observed in highly reactive children exposed to higher socioeconomic risk. Alternatively, lower exposure to socioeconomic risk was related to lower BMIz for highly reactive children.

CONCLUSIONS

Findings suggest that highly reactive PT/LBW preschoolers are differentially susceptible to early socioeconomic adversity in a for better or for worse manner regarding BMIz. Thus, consideration of temperament as a marker of biological sensitivity to context may be necessary to inform obesity prevention for PT/LBW preschoolers from low-income families. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Impact of introducing a standardized nutrition protocol on very premature infants' growth and morbidity

Background

Inappropriate nutritional intake in premature infants may be responsible for postnatal growth restriction (PGR) and adverse long-term outcomes.

Objective

We evaluated the impact of an updated nutrition protocol on very premature infants’ longitudinal growth and morbidity, and secondly the compliance to this new protocol.

Design

All infants born between 26–32 weeks gestation (GA) were studied retrospectively during two 6-month periods before (group 1) and after (group 2) the introduction of an optimized nutrition protocol, in a longitudinal comparative analysis.

Results

158 infants were included; 72 before and 86 after the introduction of the protocol (Group 1: (mean±SD) birthweight (BW) 1154±276 g, GA 29.0±1.4 weeks; Group 2: BW 1215±332 g, GA 28.9±1.7 weeks). We observed growth improvement in Group 2 more pronounced in males (weight z-score) at D42 (−1.688±0.758 vs. −1.370±0.762, p = 0.045), D49 (−1.696±0.776 vs. −1.370±0.718, p = 0.051), D56 (−1.748±0.855 vs. −1.392±0.737, p = 0.072), D63 (−1.885±0.832 vs. −1.336±0.779 p = 0.016), and D70 (−2.001±0.747 vs. −1.228±0.765 p = 0.004). There was no difference in females or in morbidities between the groups. We observed low compliance to the protocol in both groups: similar energy intake but higher lipid intake in Group 1 and higher protein intake in Group 2.

Conclusion

The quality of nutritional care with a strictly-defined protocol may significantly improve weight gain for very preterm infants. As compliance remained low, an educational reinforcement is needed to prevent PGR.

Clinical trial registration

This retrospective study was registered by ClinicalTrials.gov under number NCT03217045, and by the CNIL (Commission Nationale de l’Informatique et des Libertés) under study number R2015-1 for the Maternity of the CHRU of Nancy.

Accelerated weight gain, prematurity, and the risk of childhood obesity: A meta-analysis and systematic review

The purpose of this systematic review and meta-analysis of the literature was to analyze and evaluate the impact of prematurity and accelerated weight gain on the risk of childhood and adolescent obesity. CINAHL, Embase, PubMed, and Web of Science databases were searched until December 2019 which yielded 19 studies with a total of 169,439 children enrolled were systematically reviewed. The results revealed that preterm infants had a greater likelihood of childhood obesity (defined as BMI ≥95th percentile for age-sex), than term infants (OR = 1.19, 95% CI [1.13, 1.26]). However, no difference of childhood obesity was found between "small for gestational age"(SGA) and "appropriate for gestational age"(AGA) among preterms. Accelerated weight gain (defined as weight gain velocity during first two years after birth) significantly increased the likelihood of subsequent childhood obesity among preterms (aOR = 1.87, 95% CI [1.57, 2.231]). In conclusion, accelerated weight gain at infancy among preterm children may be a critical contributor to obesity in later life. Establishing optimal growth trajectories and timely referral to health care providers may be of clinical importance.

Growth patterns and body composition in former extremely low birth weight (ELBW) neonates until adulthood: a systematic review

Preterm infants are obviously born lighter and shorter, with smaller head circumferences than normal birth weight term born neonates. They also have a different body composition. Compromised growth is associated with adverse health outcomes. Both growth retardation and accelerated growth are suggested to cause metabolic, cardiovascular, and renal complications. Reviews regarding growth and body composition in preterm infants often do not differentiate between birth weight and gestational age. The purpose of this systematic review is to assemble growth data, specific in extremely low birth weight children. Different databases were searched for studies regarding growth and body composition in former extremely low birth weight infants until adulthood. We compared height, weight, head circumference, body mass index, fat mass, lean mass, fat distribution, and body water to matched normal birth weight controls and the World Health Organization growth charts. Studies consistently reported that former extremely low birth weight neonates experience a period of accelerated postnatal growth, but they achieve lower anthropometric parameters than normal birth weight children. There is no consensus about differences in body composition and how to measure this.Conclusion: Although extremely low birth weight infants exhibit a period of catch-up growth, their growth remains retarded later in life. Further research is needed to investigate body composition and the associated risk of cardiovascular diseases or metabolic syndrome.What is Known:• Extremely low birth weight infants have lower anthropometric parameters and a different body composition at birth and term-corrected age than normal birth weight infants.• Former extremely low birth weight infants also have a higher risk on adverse cardiovascular health outcomes in later life.What is New:• After hospital discharge, extremely low birth weight neonates remain smaller and probably also lighter, with smaller head circumferences at each corrected age throughout childhood and adolescence when compared to normal birth weight infants or the World Health Organization growth charts. It is not clear whether extremely low birth weight infants reach a lower or similar body mass index score as normal birth weight infants.• There is a lack of (long-term) information on body composition in extremely low birth weight infants.

Risk of hypertension following perinatal adversity: IUGR and prematurity

Consistent with the paradigm shifting observations of David Barker and colleagues that revealed a powerful relationship between decreased weight through 2 years of age and adult disease, intrauterine growth restriction (IUGR) and preterm birth are independent risk factors for the development of subsequent hypertension. Animal models have been indispensable in defining the mechanisms responsible for these associations and the potential targets for therapeutic intervention. Among the modifiable risk factors, micronutrient deficiency, physical immobility, exaggerated stress hormone exposure and deficient trophic hormone production are leading candidates for targeted therapies. With the strong inverse relationship seen between gestational age at delivery and the risk of hypertension in adulthood trumping all other major cardiovascular risk factors, improvements in neonatal care are required. Unfortunately, therapeutic breakthroughs have not kept pace with rapidly improving perinatal survival, and groundbreaking bench-to-bedside studies are urgently needed to mitigate and ultimately prevent the tsunami of prematurity-related adult cardiovascular disease that may be on the horizon. This review highlights our current understanding of the developmental origins of hypertension and draws attention to the importance of increasing the availability of lactation consultants, nutritionists, pharmacists and physical therapists as critical allies in the battle that IUGR or premature infants are waging not just for survival but also for their future cardiometabolic health.

Infant Feeding Practices and Weight Gain in Toddlers Born Very Preterm: A Pilot Study

PURPOSE

Long-term consequences of prematurity are a public health concern. A pattern of slow initial weight gain followed by a period of rapid weight gain has been associated with poor cardiometabolic health outcomes. The purpose of this study was to examine the relationships between infant feeding practices and weight gain in a sample of 18-to-24-month olds corrected age born very preterm.

DESIGN AND METHODS

A cross-sectional design was used to examine the relationships between infant feeding practices and weight gain. Estimates of effect sizes and model fit estimates were the primary parameters of interest.

RESULTS

Most of the participants received human milk after birth, but most had transitioned to formula before three months. Slightly less than half received complementary foods prior to four months corrected age. Gains in weight and head circumference were rapid after discharge from the neonatal intensive care unit, while gains in length lagged behind. Infant feeding practices did not have a clinically meaningful effect on weight gain.

CONCLUSIONS

While the initiation of human milk feedings was encouraging, the duration fell short of recommendations. Practices such as the early introduction of complementary feedings and the addition of rice cereal to the bottle are troubling. Additionally, the rapid increase in weight gain may have a negative impact on future cardiometabolic health.

PRACTICE IMPLICATIONS

Clinical recommendations include ensuring support for the use of human milk before and after hospital discharge, close monitoring of physical growth, and ensuring adherence to the guidelines for the introduction of complementary foods.

Antecedents of Obesity Among Children Born Extremely Preterm

BACKGROUND

Childhood obesity is a pervasive public health problem with risk factors such as maternal prepregnancy BMI and rapid infant weight gain. Although catch-up weight gain promotes more favorable neurodevelopment among infants born preterm, it is not clear whether faster weight gain early in life, or other correlates of preterm birth, are associated with later obesity in this population.

METHODS

We used prospective data from the multicenter, observational Extremely Low Gestational Age Newborn Study. Among 1506 eligible individuals in the initial cohort, 1198 were eligible for follow-up at 10 years of age. We examined BMI in 871 children (58% of the cohort; 74% of survivors) and analyzed relationships between antecedents and overweight or obesity at 10 years of age. A time-oriented approach to multinomial multivariable regression enabled us to calculate odds of overweight and obesity associated with pre- and postnatal antecedents.

RESULTS

Prepregnancy maternal BMI ≥25 and top quartile infant weight gain in the first year were associated with increased risk of both overweight and obesity at 10 years of age. Single marital status was a risk factor for later child obesity and exposure to tobacco smoke was a risk factor for later child overweight.

CONCLUSIONS

The risk profiles for overweight and obesity at 10 years of age among children born extremely preterm appear to be similar to the risk profiles of overweight and obesity among children born at term.

Neurocognitive and Health Correlates of Overweight and Obesity among Ten-Year-Old Children Born Extremely Preterm

OBJECTIVE

To assess the relationship between overweight (body mass index [BMI] percentile ≥85 and <95) and obesity (BMI ≥95 percentile) and developmental and health outcomes at 10 years of age in a cohort of individuals born extremely preterm.

STUDY DESIGN

This was an observational cohort study of children born extremely preterm and then assessed at age 10 years for neurocognitive function and parent-reported behavior and health outcomes. Participants included 871 children aged 10 years. To describe the strength of association between overweight or obesity and outcomes, we used logistic regression models adjusting for confounders. Neurocognitive function, academic achievement, parent-reported health outcome surveys, and height and weight were measured.

RESULTS

BMI category at 10 years of age was not associated with differences in intelligence, language, or academic achievement. Parents of children with obesity were more likely to report their child had asthma (OR 2.2; 95% CI 1.4-3.5), fair/poor general health (OR 3.2; 95% CI 1.4-7.5), and decreased physical function (OR 1.7; 95% CI 1.1-2.9) but less likely to have physician diagnosed attention-deficit/hyperactivity disorder (OR 0.5; 95% CI 0.3-0.97) or an individualized education plan (OR 0.6; 95% CI 0.4-0.99).

CONCLUSION

Among children born extremely preterm, an elevated BMI, compared with normal or low BMI, is not associated with a difference in neurocognitive function. However, asthma, fair/poor general health, and decreased physical function were more prevalent among study participants with obesity, and attention-deficit/hyperactivity disorder and individualized education plan were less prevalent.

Extreme Preterm Infant Rates of Overweight and Obesity at School Age in the SUPPORT Neuroimaging and Neurodevelopmental Outcomes Cohort

OBJECTIVE

To identify rates of overweight (body mass index [BMI] ≥85th percentile) and obesity (BMI ≥95th percentile) at 6-7 years of age and associated risk factors among extremely preterm infants born at <28 weeks of gestation.

STUDY DESIGN

Anthropometrics, blood pressure, and active and sedentary activity levels were prospectively assessed. Three groups were compared, those with a BMI ≥85th percentile (overweight or obese for age, height, and sex) and ≥95th percentile (obese) vs <85th percentile. Multiple regression analyses estimated the relative risks of BMI ≥85th percentile and ≥95th percentile associated with perinatal and early childhood factors.

RESULTS

Of 388 children, 22% had a BMI of ≥85th percentile and 10% were obese. Children with obesity and overweight compared with normal weight children had higher body fat (subscapular skinfold and triceps skinfold >85th percentile), central fat (waist circumference >90th percentile), spent more time in sedentary activity (20.5 vs 18.2 vs 16.7 hours/week), and had either systolic and/or diastolic hypertension (24% vs 26% vs 14%), respectively. Postdischarge weight gain velocities from 36 weeks postmenstrual age to 18 months, and 18 months to 6-7 years were independently associated with a BMI of ≥85th percentile, whereas weight gain velocity from 18 months to 6-7 years was associated with obesity.

CONCLUSIONS

One in 5 former extremely preterm infants is overweight or obese and has central obesity at early school age. Postdischarge weight gain velocities were associated with overweight and obesity. These findings suggest the obesity epidemic is spreading to the most extremely preterm infants.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00063063 and NCT0000.

Neonatal Growth Restriction Slows Cardiomyocyte Development and Reduces Adult Heart Size

Prematurity is associated with reduced cardiac dimensions and an increased risk of cardiovascular disease. While prematurity is typically associated with ex utero neonatal growth restriction (GR), the independent effect of neonatal GR on cardiac development has not been established. We tested the hypothesis that isolated neonatal GR decreases cardiomyocyte growth and proliferation, leading to long-term alterations in cardiac morphology. C57BL/6 mice were fostered in litters ranging in size from 6 to 12 pups to accentuate normal variation in neonatal growth. Regardless of litter size, GR was defined by a weight below the 10th percentile. On postnatal day 8, Ki67 immunoreactivity, cardiomyocyte nucleation status and cardiomyocyte profile area were assessed. For adult mice, cardiomyocyte area was determined, along with cardiac dimensions by echocardiography and cardiac fibrosis by Masson's trichrome stain. On day 8, cardiomyocytes from GR versus control mice were significantly smaller and less likely to be binucleated with evidence of persistent cell cycle activity. As adults, GR mice continued to have smaller cardiomyocytes, as well as decreased left ventricular volumes without signs of fibrosis. Neonatal GR reduces cardiomyocyte size, delays the completion of binucleation, and leads to long-term alterations in cardiac morphology. Clinical studies are needed to ascertain whether these results translate to preterm infants that must continue to grow and mature in the midst of the increased circulatory demands that accompany their premature transition to an ex utero existence. Anat Rec, 2018. © 2018 Wiley Periodicals, Inc.

Reading, Mathematics and Fine Motor Skills at 5 Years of Age in US Children who were Extremely Premature at Birth

Objectives The prevalence of extreme prematurity at birth has increased, but little research has examined its impact on developmental outcomes in large representative samples within the United States. This study examined the association of extreme prematurity with kindergarteners' reading skills, mathematics skills and fine motor skills. Methods The early childhood longitudinal study-birth cohort, a representative sample of the US children born in 2001 was analyzed for this study. Early reading and mathematics skills and fine motor skills were compared among 200 extremely premature children (EPC) (gestational age <28 wks or birthweight <1000 g), 500 premature children (PC), and 4300 term children (TC) (≥37wks or ≥2500 g). Generalized linear regression analyses included sampling weights, children's age, race, sex, and general health status, and parental marital status and education among singleton children. Results At age 5 years, EPC were 2.6(95 % CI 1.7-3.8) times more likely to fail build a gate and were 3.1(95 % CI 1.6-5.8) times more likely to fail all four drawing tasks compared to TC (p values <0.001). Fine motor performance of PC (failed to build a gate, 1.3[95 % CI 1.0-1.7]; failed to draw all four shapes, 1.1[95 % CI 0.8-1.6]) was not significantly different from TC. Mean early reading scale score (36.8[SE:1.3]) of EPC was 4.0 points lower than TC (p value < 0.0001) while mean reading score (39.9[SE:1.4]) of PC was not significantly different from TC (40.8[SE:1.1]). Mean mathematics scale score were significantly lower for both EPC (35.5[SE:1.0], p value < 0.001) and PC (39.8[SE:0.8], p value = 0.023) compared to TC (41.0[SE:0.6]). Conclusions for Practice Extreme prematurity at birth was associated with cognitive and fine motor delays at age 5 years. This suggests that based on a nationally representative sample of infants, the biological risk of extreme prematurity persists after adjusting for other factors related to development.

Effect of the Japanese diet during pregnancy and lactation or post-weaning on the risk of metabolic syndrome in offspring

We examined the effects on offspring of ingestion of the 1975 Japanese diet during pregnancy and lactation and after weaning in mice. Pregnant dams were divided into groups that were fed the Japanese diet or a control diet and raised until offspring were weaned. The offspring after weaning were further divided into groups that were raised on the Japanese diet or the control diet. Ingestion of the Japanese diet after weaning suppressed accumulation of visceral fat in offspring, and reduced the amount of lipids in serum and liver. This effect was weakened if the Japanese diet was only ingested during pregnancy and lactation. Therefore, it was suggested that ingestion of the Japanese diet of mothers during pregnancy and lactation weakens the lipid accumulation inhibitory effect of the Japanese diet in children.

Linear growth trajectories in Zimbabwean infants

BACKGROUND

Undernutrition in early life underlies 45% of child deaths globally. Stunting malnutrition (suboptimal linear growth) also has long-term negative effects on childhood development. Linear growth deficits accrue in the first 1000 d of life. Understanding the patterns and timing of linear growth faltering or recovery during this period is critical to inform interventions to improve infant nutritional status.

OBJECTIVE

We aimed to identify the pattern and determinants of linear growth trajectories from birth through 24 mo of age in a cohort of Zimbabwean infants.

DESIGN

We performed a secondary analysis of longitudinal data from a subset of 3338 HIV-unexposed infants in the Zimbabwe Vitamin A for Mothers and Babies trial. We used k-means clustering for longitudinal data to identify linear growth trajectories and multinomial logistic regression to identify covariates that were associated with each trajectory group.

RESULTS

For the entire population, the mean length-for-age z score declined from -0.6 to -1.4 between birth and 24 mo of age. Within the population, 4 growth patterns were identified that were each characterized by worsening linear growth restriction but varied in the timing and severity of growth declines. In our multivariable model, 1-U increments in maternal height and education and infant birth weight and length were associated with greater relative odds of membership in the least-growth restricted groups (A and B) and reduced odds of membership in the more-growth restricted groups (C and D). Male infant sex was associated with reduced odds of membership in groups A and B but with increased odds of membership in groups C and D.

CONCLUSION

In this population, all children were experiencing growth restriction but differences in magnitude were influenced by maternal height and education and infant sex, birth weight, and birth length, which suggest that key determinants of linear growth may already be established by the time of birth. This trial was registered at clinicaltrials.gov as NCT00198718.

Modeling the impact of growth and leptin deficits on the neuronal regulation of blood pressure

The risk of hypertension is increased by intrauterine growth restriction (IUGR) and preterm birth. In the search for modifiable etiologies for this life-threatening cardiovascular morbidity, a number of pathways have been investigated, including excessive glucocorticoid exposure, nutritional deficiency and aberration in sex hormone levels. As a neurotrophic hormone that is intimately involved in the cardiovascular regulation and whose levels are influenced by glucocorticoids, nutritional status and sex hormones, leptin has emerged as a putative etiologic and thus a therapeutic agent. As a product of maternal and late fetal adipocytes and the placenta, circulating leptin typically surges late in gestation and declines after delivery until the infant consumes sufficient leptin-containing breast milk or accrues sufficient leptin-secreting adipose tissue to reestablish the circulating levels. The leptin deficiency seen in IUGR infants is a multifactorial manifestation of placental insufficiency, exaggerated glucocorticoid exposure and fetal adipose deficit. The preterm infant suffers from the same cascade of events, including separation from the placenta, antenatal steroid exposure and persistently underdeveloped adipose depots. Preterm infants remain leptin deficient beyond term gestation, rendering them susceptible to neurodevelopmental impairment and subsequent cardiovascular dysregulation. This pathologic pathway is efficiently modeled by placing neonatal mice into atypically large litters, thereby recapitulating the perinatal growth restriction-adult hypertension phenotype. In this model, neonatal leptin supplementation restores the physiologic leptin surge, attenuates the leptin-triggered sympathetic activation in adulthood and prevents leptin- or stress-evoked hypertension. Further pathway interrogation and clinical translation are needed to fully test the therapeutic potential of perinatal leptin supplementation.

Challenges and opportunities in developmental integrative physiology

This review explores challenges and opportunities in developmental physiology outlined by a symposium at the 2014 American Physiological Society Intersociety Meeting: Comparative Approaches to Grand Challenges in Physiology. Across animal taxa, adverse embryonic/fetal environmental conditions can alter morphological and physiological phenotypes in juveniles or adults, and capacities for developmental plasticity are common phenomena. Human neonates with body sizes at the extremes of perinatal growth are at an increased risk of adult disease, particularly hypertension and cardiovascular disease. There are many rewarding areas of current and future research in comparative developmental physiology. We present key mechanisms, models, and experimental designs that can be used across taxa to investigate patterns in, and implications of, the development of animal phenotypes. Intraspecific variation in the timing of developmental events can be increased through developmental plasticity (heterokairy), and could provide the raw material for selection to produce heterochrony--an evolutionary change in the timing of developmental events. Epigenetics and critical windows research recognizes that in ovo or fetal development represent a vulnerable period in the life history of an animal, when the developing organism may be unable to actively mitigate environmental perturbations. 'Critical windows' are periods of susceptibility or vulnerability to environmental or maternal challenges, periods when recovery from challenge is possible, and periods when the phenotype or epigenome has been altered. Developmental plasticity may allow survival in an altered environment, but it also has possible long-term consequences for the animal. "Catch-up growth" in humans after the critical perinatal window has closed elicits adult obesity and exacerbates a programmed hypertensive phenotype (one of many examples of "fetal programing"). Grand challenges for developmental physiology include integrating variation in developmental timing within and across generations, applying multiple stressor dosages and stressor exposure at different developmental timepoints, assessment of epigenetic and parental influences, developing new animal models and techniques, and assessing and implementing these designs and models in human health and development.