Do thin, overweight and obese children have poorer development than their healthy-weight peers at the start of school? Findings from a South Australian data linkage study

Bi-directional associations between physical activity and growth indicators of pre-school aged children

Physical activity for young children provides a wealth of benefits for health and development. However, little is known about the inter-relationship of physical activity and growth indicators. The aim of this study was to test the bi-directional associations of physical activity and growth indicators in children under five years of age. This prospective study included 1,575 children with data on physical activity and growth indicators at ages 12, 24 and 48 months. Accelerometers were used to measure physical activity. Z-scores for length/height-for-age, weight-for-length/height, weight-for-age and body mass index (BMI)-for-age were calculated. Bi-directional associations between physical activity and growth indicators were evaluated using cross-lagged panels based on Generalized Estimating Equations and cross-lagged structural equation models. Physical activity was consistently associated with lower weight-related growth indicators: BMI-for-age: β=-0.12; Weight-for-age: β=-0.11; Weight-for-length/height: β=-0.12. Higher BMI-for-age indicated lower physical activity (β=-0.06). When the exposure was lagged, the association of physical activity on weight-related growth indicators remained, but weight-related growth indicators showed a negative association on physical activity. A bi-directional association between physical activity and weight-related growth indicators was observed. The magnitude of associations were stronger when physical activity was modelled as exposure. These results reinforce the importance of physical activity since early years.

Overweight/obesity and socio-demographic disparities in children's motor and cognitive function

Fundamental motor skills (FMS) and cognitive function are important indicators of development in early childhood. Using a cross-sectional design, the purpose of this study was to investigate obesity (healthy weight vs. overweight/obese) and socio-demographic (i.e., gender, SES) disparities in FMS (locomotor and ball skills) and cognitive function (reaction time [RT] and movement time [MT]), in preschoolers. There were 74 preschoolers (girl = 38; M_age = 4.02 ± 0.73) recruited from two childcare centers and were categorized into healthy weight (n = 58, BMI percentile < 85%) and overweight/obese (n = 16, BMI percentile ≥ 85%) categories. Children's FMS were assessed using the TGMD-3; cognitive function was assessed by the iPad-based CANTAB™ software using the Reaction Time Task (RTI), including reaction time (RT; Simple RT [SRT], choice RT [CRT]) and movement time (MT; simple MT [SMT], choice MT [CMT]). Children presented less FMS proficiency compared to recent data. Both weight groups performed comparably in FMS (ps > 0.05; ball skill Cohen's d = 0.40; locomotor Cohen's d = 0.02). Children in the overweight/obese group performed significantly worse on all cognitive tests compared to healthy weight peers (ps < 0.05; Cohen's d range from -0.93 to -1.43). No significant gender or SES disparities were observed. Maintaining healthy weight status is critical for cognitive development among preschoolers, which may influence their developmental trajectory and school readiness.

School-age outcomes among IVF-conceived children: A population-wide cohort study

BACKGROUND

In vitro fertilisation (IVF) is a common mode of conception. Understanding the long-term implications for these children is important. The aim of this study was to determine the causal effect of IVF conception on primary school-age childhood developmental and educational outcomes, compared with outcomes following spontaneous conception.

METHODS AND FINDINGS

Causal inference methods were used to analyse observational data in a way that emulates a target randomised clinical trial. The study cohort comprised statewide linked maternal and childhood administrative data. Participants included singleton infants conceived spontaneously or via IVF, born in Victoria, Australia between 2005 and 2014 and who had school-age developmental and educational outcomes assessed. The exposure examined was conception via IVF, with spontaneous conception the control condition. Two outcome measures were assessed. The first, childhood developmental vulnerability at school entry (age 4 to 6), was assessed using the Australian Early Developmental Census (AEDC) (n = 173,200) and defined as scoring <10th percentile in ≥2/5 developmental domains (physical health and wellbeing, social competence, emotional maturity, language and cognitive skills, communication skills, and general knowledge). The second, educational outcome at age 7 to 9, was assessed using National Assessment Program-Literacy and Numeracy (NAPLAN) data (n = 342,311) and defined by overall z-score across 5 domains (grammar and punctuation, reading, writing, spelling, and numeracy). Inverse probability weighting with regression adjustment was used to estimate population average causal effects. The study included 412,713 children across the 2 outcome cohorts. Linked records were available for 4,697 IVF-conceived cases and 168,503 controls for AEDC, and 8,976 cases and 333,335 controls for NAPLAN. There was no causal effect of IVF-conception on the risk of developmental vulnerability at school-entry compared with spontaneously conceived children (AEDC metrics), with an adjusted risk difference of -0.3% (95% CI -3.7% to 3.1%) and an adjusted risk ratio of 0.97 (95% CI 0.77 to 1.25). At age 7 to 9 years, there was no causal effect of IVF-conception on the NAPLAN overall z-score, with an adjusted mean difference of 0.030 (95% CI -0.018 to 0.077) between IVF- and spontaneously conceived children. The models were adjusted for sex at birth, age at assessment, language background other than English, socioeconomic status, maternal age, parity, and education. Study limitations included the use of observational data, the potential for unmeasured confounding, the presence of missing data, and the necessary restriction of the cohort to children attending school.

CONCLUSIONS

In this analysis, under the given causal assumptions, the school-age developmental and educational outcomes for children conceived by IVF are equivalent to those of spontaneously conceived children. These findings provide important reassurance for current and prospective parents and for clinicians.

Risk factors for developmental vulnerability: Insight from population-level surveillance using the Early Development Instrument

Objectives

Population-level studies may elucidate the most promising intervention targets to prevent negative outcomes of developmental vulnerability in children. This study aims to bridge the current literature gap on identifying population-level developmental vulnerability risk factors using combined social and biological/health information.

Methods

This study assessed developmental vulnerability among kindergarten children using the 2016 Early Development Instrument (EDI) and identified risk factors of developmental vulnerability using EDI data cross-linked to a population-wide administrative health dataset. A total number of 23,494 children aged 5-6 were included (48% female). Prenatal, neonatal, and early childhood risk factors for developmental vulnerability were investigated, highlighting the most important ones contributing to early development.

Results

The main risk factors for developmental vulnerability were children with a history of mental health diagnosis (risk ratio  = 1.46), biological sex-male (risk ratio =  1.51), and poor socioeconomic status (risk ratio =  1.58).

Conclusion

Our study encompasses both social and health information in a populational-level representative sample of Alberta, Canada. The results confirm evidence established in other geographic regions and jurisdictions and demonstrate the association between perinatal risk factors and developmental vulnerability. Based on these results, we argue that the health system should adopt a multilevel prevention and intervention strategy, targeting individual, family, and community together.

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).

Relationships between Child Development at School Entry and Adolescent Health-A Participatory Systematic Review

The relationship between child development and adolescent health, and how this may be modified by socio-economic conditions, is poorly understood. This limits cross-sector interventions to address adolescent health inequality. This review summarises evidence on the associations between child development at school starting age and subsequent health in adolescence and identifies factors affecting associations. We undertook a participatory systematic review, searching electronic databases (MEDLINE, PsycINFO, ASSIA and ERIC) for articles published between November 1990 and November 2020. Observational, intervention and review studies reporting a measure of child development and subsequent health outcomes, specifically weight and mental health, were included. Studies were individually and collectively assessed for quality using a comparative rating system of stronger, weaker, inconsistent or limited evidence. Associations between child development and adolescent health outcomes were assessed and reported by four domains of child development (socio-emotional, cognitive, language and communication, and physical development). A conceptual diagram, produced with stakeholders at the outset of the study, acted as a framework for narrative synthesis of factors that modify or mediate associations. Thirty-four studies were included. Analysis indicated stronger evidence of associations between measures of socio-emotional development and subsequent mental health and weight outcomes; in particular, positive associations between early externalising behaviours and later internalising and externalising, and negative associations between emotional wellbeing and later internalising and unhealthy weight. For all other domains of child development, although associations with subsequent health were positive, the evidence was either weaker, inconsistent or limited. There was limited evidence on factors that altered associations. Positive socio-emotional development at school starting age appears particularly important for subsequent mental health and weight in adolescence. More collaborative research across health and education is needed on other domains of development and on the mechanisms that link development and later health, and on how any relationship is modified by socio-economic context.

Physical Activity and Quality of Life in High School Students: Proposals for Improving the Self-Concept in Physical Education

Adolescence is a critical period for the acquisition of health-related behaviors that will transcend later psychological well-being in adulthood. The present study presents a theoretical model whose objective is to analyze how physical activity predicts an adequate quality of life through self-concept and subjective happiness among adolescents. A total of 452 students aged 12 to 15 (M = 13.8; SD = 0.77) from four Compulsory Secondary Education institutes of the Autonomous Community of Extremadura participated, including boys (n = 258) and girls (n = 194). The students reported information on the following variables: physical activity, body mass index, self-concept, subjective happiness, and quality of life. The results show acceptable fit indices for the proposed theoretical model, which showed the importance of physical activity through self-concept and subjective happiness in quality of life: MRLχ2 = 67.533, p < 0.05, CFI = 0.93, TLI = 0.90, SRMR = 0.05, and RMSA = 0.07. Likewise, the model presented a better fit index for males than females. This study draws conclusions on the importance of physical activity as a predictor of quality of life mediated by the perception of self-concept and mood in adolescents.

Obesity in Early Childhood: Examining the Relationship among Demographic, Behavioral, Nutritional, and Socioeconomic Factors

Background: The present study sought to explore the combined relationship of physical activity, screen time, consumption of sugar-sweetened beverages, infant feeding practices, and demographic factors with obesity in early childhood. Methods: The current study included cross-sectional Kindergarten Health Survey data collected annually from 2012 to 2016. The sample included 7814 kindergarten students, with a mean age of 5.02 [standard deviation = 0.33]. A Multinomial Logistic Regression using body mass index as the dependent variable and select demographic traits, dietary practices, sedentary behaviors, and physical activity indicators as independent variables was used to assess relationship of aforementioned factors to obesity. Results: Children were more likely to be obese if they were non-Caucasian, male, lived in rural areas, lived at or below the poverty level, had public insurance, or lived in single-parent households. Children who received less than 30 minutes of physical activity 3 or fewer days per week, had more than 2 hours of daily screen time, consumed any amount of soda, and consumed anything other than breast milk at 6 months of age also had a higher probability of being obese. Conclusions: The findings from this study suggest that investments in prevention strategies are needed to address the behavioral patterns and socioeconomic disparities before kindergarten. Efforts that increase access to nutritious food, physical activity, and overall family wellness and education, such as high-quality early childhood education, could be feasible prevention approaches.

Psychosocial health of adolescents in relation to underweight, overweight/obese status: the EU NET ADB survey

BACKGROUND

Both deviations from normal weight, namely, underweight and overweight/obese status, have been inversely associated with psychosocial health in adolescents. This study aimed to examine the relationship between psychosocial health and body mass index (BMI) among adolescents in five European countries, while assessing the effect of sociodemographic variables.

METHODS

A cross-sectional school-based study of adolescents aged 14-17.9 years was conducted in the framework of the European Network for Adolescent Addictive Behavior survey. Self-reported questionnaires from Greece, Iceland, the Netherlands, Romania and Spain were used for the current analysis. Associations between Youth Self-Report (YSR) scales and BMI status were investigated by multiple logistic regression analysis. The effect of sociodemographic variables was also measured.

RESULTS

Τhe sample consisted of 7005 adolescents aged 14-17.9 years. Borderline/clinical scores on some YSR scales were independently associated with overweight/obesity, specifically total problems (OR = 1.52, 95% CI: 1.18-1.96), internalizing ( OR = 1.48, 95% CI: 1.16-1.91), externalizing (OR = 1.36, 95% CI: 1.10-1.68), social (OR = 1.67, 95% CI: 1.19-2.35) and thought problems (OR = 1.62, 95% CI: 1.20-2.20). Among subscales, overweight/obesity specifically correlated with anxiety/depression (OR = 1.83, 95% CI: 1.33-2.51), withdrawal/depression (OR = 1.58, 95% CI: 1.02-2.48) and rule-breaking behavior (OR = 1.55, 95% CI: 1.15-2.08). Underweight was associated with problems on activities (OR = 1.31, 95% CI: 1.01-1.68) and withdrawal/depression (OR = 1.95, 95% CI: 1.27-3.01).

CONCLUSIONS

Lower levels of psychosocial health are associated with both deviations from normal weight. These findings suggest the need for health policies that target health habits and lifestyle, as well as positive attitudes towards the body image, with respect to the different psychosocial characteristics of each body weight status category.

All Children Thrive: Integration of Nutrition and Early Childhood Development

Building on the successes of child survival, we review the evidence needed to ensure both that children who survive also thrive and that recommendations promote equity, with no child left behind. To illustrate the critical roles played by nutrition and child development, we revise the Conceptual Framework for the Causes of Malnutrition and Death and the Nurturing Care Framework to create the Conceptual Framework of All Children Surviving and Thriving. The revised framework highlights the goals of child growth and development, supported by health, nutrition, learning, responsive caregiving, and security and safety. We review the challenges posed by undernutrition, stunting, micronutrient deficiencies, overweight, and children not reaching their developmental potential. Although integrated nutrition-childhood development interventions have shown promising effects, most have not been implemented at scale. Implementation science that investigates how and why integrated interventions work in real life, along with the acceptability, feasibility, cost, coverage, and sustainability of the interventions, is needed to ensure equity for all children thriving.

Cow's Milk Fat Obesity pRevention Trial (CoMFORT): a primary care embedded randomised controlled trial protocol to determine the effect of cow's milk fat on child adiposity

INTRODUCTION

Cow's milk is a dietary staple for children in North America. Though clinical guidelines suggest children transition from whole (3.25% fat) milk to reduced (1% or 2%) fat milk at age 2 years, recent epidemiological evidence supports a link between whole milk consumption and lower adiposity in children. The purpose of this trial is to determine which milk fat recommendation minimises excess adiposity and optimises child nutrition and growth.

METHODS AND ANALYSIS

Cow's Milk Fat Obesity pRevention Trial will be a pragmatic, superiority, parallel group randomised controlled trial involving children receiving routine healthcare aged 2 to 4-5 years who are participating in the TARGet Kids! practice-based research network in Toronto, Canada. Children (n=534) will be randomised to receive one of two interventions: (1) a recommendation to consume whole milk or (2) a recommendation to consume reduced (1%) fat milk. The primary outcome is adiposity measured by body mass index z-score and waist circumference z-score; secondary outcomes will be cognitive development (using the Ages and Stages Questionnaire), vitamin D stores, cardiometabolic health (glucose, high-sensitivity C-reactive protein, non-high density lipoprotein (non-HDL), low density lipoprotein (LDL), triglyceride, HDL and total cholesterol, insulin and diastolic and systolic blood pressure), sugary beverage and total energy intake (measured by 24 hours dietary recall) and cost effectiveness. Outcomes will be measured 24 months postrandomisation and compared using analysis of covariance (ANCOVA), adjusting for baseline measures.

ETHICS AND DISSEMINATION

Ethics approval has been obtained from Unity Health Toronto and The Hospital for Sick Children. Results will be presented locally, nationally and internationally and published in a peer-reviewed journal. The findings may be helpful to nutrition guidelines for children in effort to reduce childhood obesity using a simple, inexpensive and scalable cow's milk fat intervention.

TRIAL REGISTRATION NUMBER

NCT03914807; pre-results.

Fit for School Study protocol: early child growth, health behaviours, nutrition, cardiometabolic risk and developmental determinants of a child's school readiness, a prospective cohort

INTRODUCTION

School readiness is a multidimensional construct that includes cognitive, behavioural and emotional aspects of a child's development. School readiness is strongly associated with a child's future school success and well-being. The Early Development Instrument (EDI) is a reliable and valid teacher-completed tool for assessing school readiness in children at kindergarten age. A substantial knowledge gap exists in understanding how early child growth, health behaviours, nutrition, cardiometabolic risk and development impact school readiness. The primary objective was to determine if growth patterns, measured by body mass index trajectories in healthy children aged 0-5 years, are associated with school readiness at ages 4-6 years (kindergarten age). Secondary objectives were to determine if other health trajectories, including health behaviours, nutrition, cardiometabolic risk and development, are associated with school readiness at ages 4-6 years. This paper presents the Fit for School Study protocol.

METHODS AND ANALYSIS

This is an ongoing prospective cohort study. Parents of children enrolled in the The Applied Health Research Group for Kids (TARGet Kids!) practice-based research network are invited to participate in the Fit for School Study. Child growth, health behaviours, nutrition, cardiometabolic risk and development data are collected annually at health supervision visits and linked to EDI data collected by schools. The primary and secondary analyses will use a two-stage process: (1) latent class growth models will be used to first determine trajectory groups, and (2) generalised linear mixed models will be used to examine the relationship between exposures and EDI results.

ETHICS AND DISSEMINATION

The research ethics boards at The Hospital for Sick Children, Unity Health Toronto and McMaster University approved this study, and research ethics approval was obtained from each school board with a student participating in the study. The findings will be presented locally, nationally and internationally and will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT01869530.

Assessment of Biochemical Bone Turnover Markers and Bone Mineral Density in Thin and Normal-Weight Children

Objective There is scant research examining the prevalence of thinness in early childhood, despite its potential negative consequences for health and development across the life course. The objective of this study was to assess bone status through measurement of bone mineral density and biochemical bone turnover markers, with special attention paid to carboxylated (c-OC) as well as undercarboxylated (uc-OC) forms of osteocalcin, in the groups of thin and normal-weight children. Design The study included 80 healthy prepubertal children (median age 7.0 years), who were divided (according to Cole's international cutoffs) into 2 subgroups: thin children ( n = 40, body mass index [BMI] = 13.5 kg/m²) and normal-weight children ( n = 40, BMI = 16.1 kg/m²). Bone mineral density (BMD) and bone mineral content (BMC) were assessed by dual-energy x-ray absorptiometry method. Serum concentrations of C-terminal telopeptide of collagen type I (CTX), total osteocalcin (OC), and c-OC, and uc-OC forms of osteocalcin were determined using enzyme-linked immunosorbent assays. Results In thin children, we observed higher levels of bone resorption marker CTX compared with normal-weight peers. Total osteocalcin concentrations were comparable in both groups of children; however, in thin children we observed higher median values of uc-OC (34.40 vs. 29.30 ng/mL, P < 0.05) and similar c-OC levels (25.65 vs. 28.80 ng/mL). The ratio of c-OC to uc-OC was significantly lower ( P < 0.05) in thin than in normal-weight children. Total BMD and BMC were significantly decreased ( P < 0.0001) in thin children compared with normal-weight peers (0.724 ± 0.092 vs. 0.815 ± 0.060 g/cm² and 602.7 ± 159.2 vs. 818.2 ± 220.1 g, respectively). Conclusion Increased concentrations of CTX and uc-OC might lead to disturbances in bone turnover and a decrease in bone mineral density in thin children.

Kindergarten readiness for low-income and ethnically diverse children attending publicly funded preschool programs in Miami

Using data from the Miami School Readiness Project (MSRP), we examine the kindergarten readiness of five cohorts (2002-2007) of children from low-income, ethnically, and linguistically diverse families (n = 16,176) in Miami, Florida who experienced three types of publicly funded preschool programs the year before kindergarten: public school-based pre-K, center-based care, or family childcare. Black and Latino children in public school-based pre-K programs consistently demonstrated greater kindergarten readiness when compared with their classmates in center-based and family childcare, controlling for demographic variables and cognitive skills at preschool entry. In most cases, low-income children enrolled in center-based care also exhibited greater kindergarten skills than their classmates who had attended family childcare. Results were the same across ethnic and language groups. Thus, for all groups of children, those who attended public school-based pre-K began kindergarten with a stronger start than their classmates who attended center-based care and family childcare, and they continued to do better at the end of the kindergarten year.