Assessing early growth and adiposity: report from an EarlyNutrition Academy workshop

Association of anthropometric z score with complications and length of hospital stay in children with severe pneumonia aged 3 months to 5 years

BACKGROUND

Severe pneumonia in children accounts for a significant healthcare burden, involving prolonged hospitalization and increased risk of complications. The prognosis is closely related to the child's nutrition status. Anthropometric z scores are preferred to evaluate growth levels in children. This study aimed to investigate the association of anthropometric z scores with complications and length of hospital stay (LOS) in children with severe pneumonia.

METHODS

This study included 361 hospitalized children aged 3 months to 5 years with severe pneumonia in Tianjin, China. Anthropometry was performed, and anthropometric z scores were calculated. Blood laboratory indices were assessed, and complications and LOS were recorded.

RESULTS

The average anthropometric z scores were -0.10 ± 1.15 (body mass index for age z score), 0.00 ± 0.97 (upper arm circumference for age z score [ACAZ]), and -0.14 ± 1.00 (triceps skinfold thickness for age z score [TSAZ]). The prevalence of complications was 73.96% (n = 267), including 82 children with only respiratory complications, 71 with only extrapulmonary complications, and 114 with both. After adjusting for confounding factors, compared with the noncomplication group, only the extrapulmonary complication group had a lower TSAZ (odds ratio [OR] = 0.597; 95% CI = 0.405-0.880; P < 0.05), whereas the respiratory and extrapulmonary complication group had a lower ACAZ (OR = 0.674; 95% CI = 0.469-0.969; P < 0.05) and TSAZ (OR = 0.573; 95% CI = 0.389-0.843; P < 0.05). ACAZ (β = -0.368; 95% CI = -0.720 to 0.016; P < 0.05) and TSAZ (β = -1.123; 95% CI = -1.470 to -0.777; P < 0.05) were negatively correlated with LOS.

CONCLUSION

ACAZ and TSAZ were associated with complications and LOS of severe pneumonia in children aged 3 months to 5 years.

Relationships between the Intakes of Human Milk Components and Body Composition of Breastfed Infants: A Systematic Review

Human milk provides all of the elements necessary for infant growth and development. Previous studies have reported associations between breastfeeding and a reduced risk of developing obesity and late-onset metabolic disorders; however, the underlying mechanisms are poorly understood. Recently, intakes of human milk components have been associated with infant body composition, which is likely partially implicated in the reduced risk of developing childhood obesity among breastfed infants. In this systematic review, we searched electronic bibliographic databases for studies that explored relationships between the 24 h intakes of human milk macronutrients and bioactive components and infant body composition and/or growth parameters. Of 13 eligible studies, 10 assessed relationships of infant body composition and growth outcomes with human milk macronutrients, while 8 studies assessed relationships with human milk bioactive components. Significant time-dependent relationships with infant anthropometrics and body composition were found for intakes and no relationships for concentrations of several human milk components, such as lactose, total protein, and human milk oligosaccharides, suggesting that measuring concentrations of human milk components without quantifying the intake by the infant may provide a limited understanding. Future studies investigating the effect of human milk components on infant growth and body composition outcomes should consider measuring the actual intake of components and employ standardised methods for measuring milk intake.

Body composition in preterm infants: a systematic review on measurement methods

BACKGROUND

There are several methods to measure body composition in preterm infants. Yet, there is no agreement on which method should be preferred.

METHODS

PubMed, Embase.com, Wiley/Cochrane Library, and Google Scholar were searched for studies that reported on the predictive value or validity of body composition measurements in preterms, up to 6 months corrected age.

RESULTS

Nineteen out of 1884 identified studies were included. Predictive equations based on weight and length indices, body area circumferences, skinfold thickness, bioelectrical impedance, and ultrasound did not show agreement with body composition measured with air displacement plethysmography (ADP), dual-energy x-ray absorptiometry (DXA), magnetic resonance imaging (MRI), or isotope dilution. ADP agreed well with fat mass density measured by isotope dilution (bias -0.002 g/ml, limits of agreement ±0.012 g/ml, n = 14). Fat mass percentage measured with ADP did not agree well with fat mass percentage measured by isotope dilution (limits of agreement up to ±5.8%) and the bias between measurements was up to 2.2%. DXA, MRI, and isotope dilution were not compared to another reference method in preterms.

CONCLUSIONS

DXA, ADP, and isotope dilution methods are considered trustworthy validated techniques. Nevertheless, this review showed that these methods may not yield comparable results.

IMPACT

Based on validation studies that were conducted in a limited number of study subjects, weight and length indices, body area circumferences, skinfold thickness, bioelectrical impedance, and ultrasound seem to be a poor representation of body composition in preterm infants. DXA, ADP, and isotope dilution methods are considered trustworthy and validated techniques. Nevertheless, these methods may not yield comparable results.

Body Weight at Age Four Years and Readiness to Start School: A Prospective Cohort Study

Background: Adolescents with obesity have lower academic performance, but little is known about the association between body weight in early childhood and school readiness. The objective was to examine the association between age- and sex-standardized body mass index (zBMI) and body weight status and school readiness in young children. Methods: A prospective cohort study in Toronto, Canada, was conducted in young children enrolled in TARGet Kids!. Children's weight and height were measured before the start of kindergarten. Children's school readiness was measured by the Early Development Instrument (EDI), a validated teacher-completed instrument that assesses children's skills and behaviors in five developmental domains in kindergarten. Generalized estimating equations, adjusted for relevant confounders, were used in the analysis. Results: The study included 1015 children (1217 observations): 52% were male and mean age at zBMI was 4.2 years [50 months (SD 12.1)] and school readiness was 5.2 years [62.7 months (SD 6.9)]. There was no evidence found that zBMI was associated with school readiness. However, in a post hoc analysis, being classified as overweight or with obesity in kindergarten was associated with twofold higher odds of vulnerability in school readiness and a lower social competence score compared with their normal weight peers. Conclusions: Being classified as overweight or with obesity was associated with poor school readiness in year 2 of kindergarten. Early interventions to promote healthy growth before school entry may help promote development and school readiness in young children. www.clinicaltrials.gov (NCT01869530).

Human Milk Macronutrients and Bioactive Molecules and Development of Regional Fat Depots in Western Australian Infants during the First 12 Months of Lactation

We investigated associations between intakes of human milk (HM) components (macronutrients and biologically active molecules) and regional fat depots development in healthy term infants (n = 20) across the first year of lactation. Infant limb (mid-arm and mid-thigh) lean and fat areas were assessed by ultrasound imaging at 2, 5, 9 and 12 months of age. Concentrations of HM total protein, whey protein, casein, adiponectin, leptin, lysozyme, lactoferrin, secretory IGA, total carbohydrates, lactose, HM oligosaccharides (total HMO, calculated) and infant 24-h milk intake were measured, and infant calculated daily intakes (CDI) of HM components were determined. This pilot study shows higher 24-h milk intake was associated with a larger mid-arm fat area (p = 0.024), higher breastfeeding frequency was associated with larger mid-arm (p = 0.008) and mid-thigh (p < 0.001) fat areas. Lysozyme (p = 0.001) and HMO CDI (p = 0.004) were time-dependently associated with the mid-arm fat area. Intakes of HM components and breastfeeding parameters may modulate infant limb fat depots development during the first year of age and potentially promote favorable developmental programming of infant body composition; however, further studies are needed to confirm these findings.

Weight-for-Height, Body Fat, and Development in Children in the East Asia and Pacific Region

IMPORTANCE

Weight-for-height z score (WHZ) is a standard indicator of children's nutritional status even though it does not fully reflect body fat.

OBJECTIVE

To examine the combined association of WHZ and body fat with early development in the East Asia and Pacific region.

DESIGN, SETTING, AND PARTICIPANTS

Children from the East Asia-Pacific Early Child Development Scales validation study, with full data available regarding their nutritional status and outcomes, were included in this cross-sectional analysis. In brief, a multilevel stratified random sampling was used to select representative samples from each participating country in the study. WHZ and body fat were independently trichotomized using established references and were combined to form a 9-category exposure variable. Data collection was performed between 2012 and 2014, and the analyses were conducted in June 2021.

MAIN OUTCOMES AND MEASURES

The binary outcome variable of not being developmentally on track (hereafter referred to as poor development) was defined as a score less than the 25th percentile in the following domains: cognitive, language, socioemotional, motor development, and total development score. Poisson regression models were used to analyze the associations between the combined categories and poor development, adjusted for sociodemographic factors.

RESULTS

A total of 6815 children (mean [SD] age, 4.02 [0.8] years; 3434 girls [50.4%]) had full data available and were included in this study. Compared with children with normal weight and normal fat, those with wasting and low body fat had the highest likelihood of total poor development (prevalence ratio, 1.47; 95% CI, 1.28-1.70), followed by those with normal weight but low fat (prevalence ratio, 1.23; 95% CI, 1.11-1.36). Similar associations were found in language, cognitive, and socioemotional development, but not in motor development.

CONCLUSIONS AND RELEVANCE

Poor development was more commonly found in children with low body fat independent of WHZ (wasted or normal weight). Early public health strategies may consider using a combination of WHZ and body fat as an indicator of poor development.

Causative Mechanisms of Childhood and Adolescent Obesity Leading to Adult Cardiometabolic Disease: A Literature Review

The past few decades have shown a worrisome increase in the prevalence of obesity and its related illnesses. This increasing burden has a noteworthy impact on overall worldwide mortality and morbidity, with significant economic implications as well. The same trend is apparent regarding pediatric obesity. This is a particularly concerning aspect when considering the well-established link between cardiovascular disease and obesity, and the fact that childhood obesity frequently leads to adult obesity. Moreover, most obese adults have a history of excess weight starting in childhood. In addition, given the cumulative character of both time and severity of exposure to obesity as a risk factor for associated diseases, the repercussions of obesity prevalence and related morbidity could be exponential in time. The purpose of this review is to outline key aspects regarding the current knowledge on childhood and adolescent obesity as a cardiometabolic risk factor, as well as the most common etiological pathways involved in the development of weight excess and associated cardiovascular and metabolic diseases.

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.

Body composition techniques

Body composition is known to be associated with several diseases, such as cardiovascular disease, diabetes, cancers, osteoporosis and osteoarthritis. Body composition measurements are useful in assessing the effectiveness of nutritional interventions and monitoring the changes associated with growth and disease conditions. Changes in body composition occur when there is a mismatch between nutrient intake and requirement. Altered body composition is observed in conditions such as wasting and stunting when the nutritional intake may be inadequate. Overnutrition on the other hand leads to obesity. Many techniques are available for body composition assessment, which range from simple indirect measures to more sophisticated direct volumetric measurements. Some of the methods that are used today include anthropometry, tracer dilution, densitometry, dual-energy X-ray absorptiometry, air displacement plethysmography and bioelectrical impedance analysis. The methods vary in their precision and accuracy. Imaging techniques such as nuclear magnetic resonance imaging and computed tomography have become powerful tools due to their ability of visualizing and quantifying tissues, organs, or constituents such as muscle and adipose tissue. However, these methods are still considered to be research tools due to their cost and complexity of use. This review was aimed to describe the commonly used methods for body composition analysis and provide a brief introduction on the latest techniques available.

Obesity in Children: Definition, Etiology and Approach

Childhood obesity is an important public health issue worldwide. Urbanization, sedentary lifestyle and change in food habits are the chief reasons behind this pandemic. In a small proportion of children, obesity is the result of endocrine, syndromic or monogenic causes. The present paper summarizes the methods, definitions and cut-offs for identification of obesity in children. We have briefly reviewed the various techniques used for estimation of body fat in children and the cut-offs for defining obesity based on body fat percentage, and the reference curves based on body mass index and waist circumference. The etiology of obesity in children, including individual behaviors, macro- and micro-environmental influences, and endocrine causes have been discussed, and an approach to etiological assessment of obese children has been presented. Special emphasis has been laid on clinical pointers that suggest the presence of syndromic, endocrine or monogenic forms of obesity, such as, short stature, dysmorphism, neurocognitive impairment and early age at onset.

Advances in assessing body composition during pregnancy

The prevalence of excess gestational weight gain is increasing worldwide and is associated with pregnancy complications, including gestational diabetes mellitus, pre-eclampsia, preterm birth, macrosomia, and development of obesity in offspring. Whereas gestational weight gain positively correlates with the gain in fat mass (FM), fat-free mass (FFM) gain is relatively consistent across pregnancies. Commonly used methods to assess body composition include anthropometry, densitometry (air displacement plethysmography, underwater weighing), and hydrometry (isotope dilution, bioimpedance analysis). While these techniques can be applied to pregnancy, they require specific adjustments to assumptions inherent within each method, most importantly to accommodate for the hydration of FFM which is transient throughout gestation. Here we discuss the application of the abovementioned methods to pregnant women and the relevant adjustments needed to more accurately calculate FM based on body weight, body volume, or total body water. We also present a novel application of classical data to provide FFM density estimates for pregnant women at any stage of pregnancy. Use of these adjustments will help standardize assumptions on FFM hydration and minimize error in FM estimation. Techniques still fail, however, to fully distinguish tissue gains between mother and fetus. To fill this important gap, imaging techniques such as ultrasound and magnetic resonance imaging are being used more frequently and will provide more insight into fetal development, fetal adiposity, and depot specificity of maternal FM acquisition. Efforts to synchronize protocols are necessary to allow seamless comparison of data to advance the understanding of maternal body composition changes that contribute to pregnancy-related complications.

Length-free near infrared measurement of newborn malnutrition

Under-nutrition in neonates can cause immediate mortality, impaired cognitive development and early onset adult disease. Body fat percentage measured using air-displacement-plethysmography has been found to better indicate under-nutrition than conventional birth weight percentiles. However, air-displacement-plethysmography equipment is expensive and non-portable, so is not suited for use in developing communities where the burden is often the greatest. We proposed a new body fat measurement technique using a length-free model with near-infrared spectroscopy measurements on a single site of the body - the thigh. To remove the need for length measurement, we developed a model with five discrete wavelengths and a sex parameter. The model was developed using air-displacement-plethysmography measurements in 52 neonates within 48 hours of birth. We identified instrumentation required in a low-cost LED-based screening device and incorporated a receptor device that can increase the amount of light collected. This near-infrared method may be suitable as a low cost screening tool for detecting body fat levels and monitoring nutritional interventions for malnutrition in neonates and young children in resource-constrained communities.

A comparison of body composition estimates using dual-energy X-ray absorptiometry and air-displacement plethysmography in South African neonates

BACKGROUND/OBJECTIVES

Neonatal body composition is an important predictor of future metabolic risk; however, the comparability of objective assessment techniques, particularly in African populations undergoing rapid health transition, is not known. This paper compares body composition estimates by air-displacement plethysmography (ADP) and dual-energy X-ray absorptiometry (DXA) in South African neonates.

SUBJECTS/METHODS

Fat mass, fat-free mass and body fat percentage (%fat) estimates by ADP and DXA were compared in 88 urban, black South African neonates. The level of agreement between the techniques was assessed using Bland-Altman analyses.

RESULTS

Significant correlations were observed between ADP and DXA measurements of fat mass (r=0.766), fat-free mass (r=0.942) and %fat (r=0.630); however, ADP estimates of fat mass (408±172 g vs 337±165 g; P<0.001) and %fat (12.9±4.4% vs 9.9±4%; P<0.001) were significantly higher and fat-free mass (2681±348 g vs 2969±375 g; P<0.001) significantly lower than those by DXA. Fat-free mass estimates showed greater consistency in the level of agreement between the techniques compared with fat and %fat estimates where the differences between methods were less predictable.

CONCLUSION

Although ADP and DXA body composition estimates are highly correlated in neonates, significant differences are observed between the techniques. This is particularly relevant for fat mass and %fat estimates, where differences are highly variable between methods. Further investigation is needed to minimise inter-method differences to ensure accurate and comparable assessment of body composition at birth and across longitudinal study follow-up.

Body composition of term healthy Indian newborns

BACKGROUND/OBJECTIVES

Previous anthropometry-based studies have suggested that in Indian newborns fat mass is conserved at the expense of lean tissue. This study was undertaken to assess the body composition of Indian newborns and to evaluate its relation with parents' anthropometry, birth weight and early postnatal weight gain.

SUBJECTS/METHODS

Body composition of healthy term singleton newborns was assessed by the deuterium dilution method in the second week of life. Anthropometry was carried out at birth and on the day of study.

RESULTS

Data from 127 babies were analyzed. Birth weight was 2969±383 g. Body composition was assessed at a mean age of 12.7±3.1 days. Fat and fat-free mass were 354±246 and 2764±402 g, respectively, and fat mass percentage (FM%) was 11.3±7.3%. Birth weight and fat-free mass were higher among boys, but no gender difference was noted in FM%. Birth weight was positively correlated with fat as well as fat-free mass but not FM%. FM% showed positive correlation with gain in weight from birth to the day of assessment.

CONCLUSIONS

This is the first study from India to report body composition in newborns using deuterium dilution. FM% was comparable to that reported for Western populations for babies of similar age. Our results suggest that the percentage of fat and fat-free mass is relatively constant over the range of birth weights included in this study, and greater weight gain during early postnatal period results in greater increase in FM%.

Assessment of cardiometabolic risk in children in population studies: underpinning developmental origins of health and disease mother-offspring cohort studies

Pregnancy and birth cohorts have been utilised extensively to investigate the developmental origins of health and disease, particularly in relation to understanding the aetiology of obesity and related cardiometabolic disorders. Birth and pregnancy cohorts have been utilised extensively to investigate this area of research. The aim of the present review was twofold: first to outline the necessity of measuring cardiometabolic risk in children; and second to outline how it can be assessed. The major outcomes thought to have an important developmental component are CVD, insulin resistance and related metabolic outcomes. Conditions such as the metabolic syndrome, type 2 diabetes and CHD all tend to have peak prevalence in middle-aged and older individuals but assessments of cardiometabolic risk in childhood and adolescence are important to define early causal factors and characterise preventive measures. Typically, researchers investigating prospective cohort studies have relied on the thesis that cardiovascular risk factors, such as dyslipidaemia, hypertension and obesity, track from childhood into adult life. The present review summarises some of the evidence that these factors, when measured in childhood, may be of value in assessing the risk of adult cardiometabolic disease, and as such proceeds to describe some of the methods for assessing cardiometabolic risk in children.

Regulation of early human growth: impact on long-term health

Growth and development are central characteristics of childhood. Deviations from normal growth can indicate serious health challenges. The adverse impact of early growth faltering and malnutrition on later health has long been known. In contrast, the impact of rapid early weight and body fat gain on programming of later disease risk have only recently received increased attention. Numerous observational studies related diet in early childhood and rapid early growth to the risk of later obesity and associated disorders. Causality was confirmed in a large, double-blind randomised trial testing the 'Early Protein Hypothesis'. In this trial we found that attenuation of protein supply in infancy normalized early growth and markedly reduced obesity prevalence in early school age. These results indicate the need to describe and analyse growth patterns and their regulation through diet in more detail and to characterize the underlying metabolic and epigenetic mechanisms, given the potential major relevance for public health and policy. Better understanding of growth patterns and their regulation could have major benefits for the promotion of public health, consumer-orientated nutrition recommendations, and the development of improved food products for specific target populations.

The Power of Programming and the EarlyNutrition project: opportunities for health promotion by nutrition during the first thousand days of life and beyond

At The Power of Programming 2014 Conference, researchers from multiple disciplines presented and discussed the effects of early nutrition and other environmental cues during the first thousand days of life and beyond on the lifelong risk of noncommunicable diseases. This paper aims to summarize the concepts and some of the first achievements of the EarlyNutrition research project that initiated the conference. The EarlyNutrition consortium is a multinational, multidisciplinary research collaboration of researchers from Europe, the USA, and Australia. A focus is placed on exploration of the developmental origins of obesity, adiposity, and related health outcomes. Here we report on the first findings of experimental approaches, cohort studies, randomized clinical trials, and systematic reviews of current information, as well as position papers, which have all been developed with the involvement of project partners. We conclude that the EarlyNutrition project has successfully established itself during the first 2 project years as a very strong platform for collaborative research on early programming effects. The first results, available already at this early stage of the project, point to great opportunities for health prevention strategies via the implementation of dietary and lifestyle modifications, with large effect sizes. Further results are expected which should support improved recommendations and related policies for optimized nutrition and lifestyle choices before and during pregnancy, in infancy, and in early childhood.

How growth due to infant nutrition influences obesity and later disease risk

Infant nutrition has a major impact on immediate outcomes and long-term health and later disease risks, such as obesity and related disorders, a phenomenon referred to as 'metabolic programming'. This review discusses the currently postulated hypotheses and mechanisms investigated by the EarlyNutrition project.

CONCLUSION

Rapid weight gain in the first 2 years of life, most notably mediated by diary protein, affects the insulin-like growth factor metabolic pathways. Epigenetic processes seem to play a role.

Methodologies to assess paediatric adiposity

INTRODUCTION

Childhood obesity is associated with increased risk of adult obesity, cardiovascular disease, diabetes and cancer. Appropriate techniques for assessment of childhood adiposity are required to identify children at risk. The aim of this review was to examine core clinical measurements and more technical tools to assess paediatric adiposity.

METHODS

The online databases PubMed, CINALH and EMBASE were searched and the abstracts identified were reviewed to determine appropriate studies. Their reference lists were also searched to identify further eligible studies. Publications were included if they described childhood measurement techniques or involved validation.

RESULTS AND DISCUSSION

There are many body composition assessment tools available, none of which are direct. Each technique has limitations and a combination of methods may be used. The main clinical techniques are weight, height, body mass index (BMI) and circumferences which provide sufficient information to enable classification of overweight or obesity when growth centile charts and ratios are employed. Further investigation depends on resources available and examiner skill. Skinfold thicknesses are cost-effective but require technical training and only measure subcutaneous fat. Dual energy X-ray absorptiometry (DEXA), air displacement plethysmography (ADP), magnetic resonance imaging (MRI) and computed tomography (CT) are more costly and intensive, requiring the child to remain still for longer periods. DEXA and ADP are capable of accurately measuring adiposity but are unable to distinguish between fat depots. MRI and CT can distinguish intra-abdominal from subcutaneous adiposity and are considered gold standards, but CT is unsuitable for adiposity measurement in children due to high levels of radiation exposure. Ultrasound is a promising technique capable of measuring intra-abdominal adiposity in children but requires further validation.

CONCLUSION

The core clinical measurements of weight, height, BMI and circumferences are sufficient to enable diagnosis of paediatric overweight and obesity while more technical tools provide further insight.