Longitudinal Associations Between Childhood Obesity and Academic Achievement: Systematic Review with Focus Group Data

Academic achievement and healthy lifestyle habits in primary school children: an interventional study

Purposes

First, to examine the relationship between primary school children's academic achievement and healthy lifestyle habits. Second, to evaluate the effectiveness of two different 5-month physical education interventions (traditional physical education vs. coordinative physical education) on children's academic achievement. Third, to examine whether variations of anthropometric variables, fitness level, gross motor coordination, physical activity level, sedentary time, attentional performance, fruit and vegetable consumption, meal frequency and type of physical education intervention could predict children's academic achievement variations.

Methods

Before and after the intervention, Italian language and mathematics skills, anthropometric variables (weight, height, body fat percentage, BMI), physical fitness (aerobic fitness, muscular strength, flexibility), gross motor coordination, attentional performance (processing speed, concentration performance, performance accuracy, attentional and inhibitory control), physical activity level, sedentary time and eating habits (meal frequency, fruit and vegetable consumption) were assessed in 161 Italian primary school children, randomly assigned to a traditional physical education group or to a coordinative physical education group.

Results

Physical activity level, gross motor coordination and aerobic fitness moderately predicted mathematics skill (R2 = 17%). Moreover, physical activity level, aerobic fitness and muscular strength moderately predicted Italian language skill (R2 = 21%). Intervention type differently affected academic achievement. Specifically, Italian language and mathematics skills significantly improved only after traditional intervention. Fruit consumption increase was positively associated with the improvement in academic achievement. Coordinative physical education intervention was associated with a lower probability of improvement in Italian language and mathematical skills.

Conclusion

Motor ability and lifestyle habits may have a positive influence on academic achievement in children. Unexpectedly, traditional physical education intervention resulted to be more effective on both Italian language and mathematical skills.

Cognitive function 10 years after adolescent bariatric surgery

BACKGROUND

Adolescent bariatric surgery produces substantial weight loss and reduction of medical co-morbidities. Research in adult samples shows improved cognitive function postoperatively, although much less is known about the potential cognitive benefits of bariatric surgery in adolescents-especially at extended follow-up.

OBJECTIVE

Examine cognitive function 10 years after adolescent bariatric surgery.

SETTING

University hospital.

METHODS

A total of 99 young adults who underwent bariatric surgery as adolescents completed a computerized cognitive test battery as part of a larger 10-year postoperative assessment. All had been long-term participants in the Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) study.

RESULTS

Cognitive dysfunction was prevalent on tests of attention and executive function (e.g., Continuous Performance Test - Reaction Time 30%; Maze Errors - Overrun 30%), and 53.5% met research criteria for mild cognitive impairment (MCI). Modified Poisson regression with robust error variance revealed participants with preoperative hypertension and those completing Roux-en-Y gastric bypass were more likely to meet criteria for MCI at 10-year follow-up.

CONCLUSIONS

The current findings indicate that cognitive deficits are common 10 years after bariatric surgery. Additional studies are needed to clarify possible cohort effects, determine whether these cognitive deficits persist to even later follow-up (e.g., 20 yr after surgery), and identify underlying mechanisms and mitigation strategies.

Discriminating factors of body composition characteristics for academic performance in nursing college students: a cross-sectional study

BACKGROUND

Poor body composition may affect health status, and better body composition is often associated with better academic performance. Nursing students face heavy academic and practical pressures, and the relationship between body composition and academic performance in this group is not fully understood.

METHODS

This cross-sectional observational study used de-identified student data from a university of technology in southern Taiwan to analyze the correlation between body composition characteristics and academic performance using regression models.

RESULTS

A total of 275 nursing college students were divided into four groups according to academic performance. The group with the lowest academic performance had a lower percentage of body fat (P < 0.05) but a higher percentage of muscle mass (P < 0.05) than the other three groups. Academic performance was positively correlated with percentage of body fat (R = 0.16, P < 0.01) and body age (R = 0.41, P < 0.01), but was negatively correlated with percentage of muscle mass (R = - 0.16, P < 0.01). Percentage of body fat, visceral fat area, and body age were significant discriminators of academic performance (P < 0.05).

CONCLUSIONS

The relationship between academic performance and body composition among nursing college students is not straightforward. Contrary to our initial hypothesis, students with higher academic performance tended to have a higher percentage of body fat and a lower percentage of muscle mass. Percentage of body fat, visceral fat area, and body age were significant discriminators of academic performance, indicating that body composition should be considered an important factor in nursing education and practice.

The relationship between overweight and education revisited: a test of the selection hypothesis based on adolescents' educational aspirations

OBJECTIVES

This paper examines the selection mechanism underlying the association between overweight/obesity and educational aspirations of adolescents.

STUDY DESIGN

This is a cross-sectional study based on a survey conducted in secondary schools in Spain in 2016.

METHODS

We estimate linear probability models to determine the association between adolescents' body mass index (BMI) and their expectations to obtain a university degree, as well as their school choices representing the most usual path towards higher studies. To address the potential endogeneity of BMI, we use the instrumental variables (IV) method. Additionally, we account for potential unobserved heterogeneity by including school fixed-effects and a wide set of individual and family characteristics in our analysis.

RESULTS

Our results indicate that adolescents with a higher BMI have lower expectations to obtain a university degree and are less likely to enrol in high school with the intention to pursue higher education in the future. The estimated effect is quite sizable and statistically significant only for girls. We estimate that a five-unit increase in BMI (e.g., the change between healthy weight and overweight) reduces girls' expectations to complete higher education by 19 percentage points and odds of enrolling in high school (vs. vocational training) by 21 percentage points.

CONCLUSIONS

We provide empirical evidence supporting the selection hypothesis behind the relationship between BMI and adolescents' educational aspirations. That is, unhealthy weight in adolescence is associated with poorer aspirations for further education. Lower educational aspirations during adolescence can lead to lower academic achievement, which in turn, may result in poorer health, labour market outcomes, and well-being during adulthood.

Overweight/Obesity-related microstructural alterations of the fimbria-fornix in the ABCD study: The role of aerobic physical activity

Childhood overweight/obesity has been associated with negative consequences related to brain function and may involve alterations in white matter pathways important for cognitive and emotional processing. Aerobic physical activity is a promising lifestyle factor that could restore white matter alterations. However, little is known about either regional white matter alterations in children with overweight/obesity or the effects of aerobic physical activity targeting the obesity-related brain alterations in children. Using a large-scale cross-sectional population-based dataset of US children aged 9 to 10 years (n = 8019), this study explored the associations between overweight/obesity and microstructure of limbic white matter tracts, and examined whether aerobic physical activity may reduce the overweight/obesity-related white matter alterations in children. The primary outcome measure was restriction spectrum imaging (RSI)-derived white matter microstructural integrity measures. The number of days in a week that children engaged in aerobic physical activity for at least 60 minutes per day was assessed. We found that females with overweight/obesity had lower measures of integrity of the fimbria-fornix, a major limbic-hippocampal white matter tract, than their lean peers, while this difference was not significant in males. We also found a positive relationship between the number of days of aerobic physical activity completed in a week and integrity measures of the fimbria-fornix in females with overweight/obesity. Our results provide cross-sectional evidence of sex-specific microstructural alteration in the fimbria-fornix in children with overweight/obesity and suggest that aerobic physical activity may play a role in reducing this alteration. Future work should examine the causal direction of the relationship between childhood overweight/obesity and brain alterations and evaluate potential interventions to validate the effects of aerobic physical activity on this relationship.

Umbrella systematic review finds limited evidence that school absence explains the association between chronic health conditions and lower academic attainment

Introduction

Absence from school is more frequent for children with chronic health conditions (CHCs) than their peers and may be one reason why average academic attainment scores are lower among children with CHCs.

Methods

We determined whether school absence explains the association between CHCs and academic attainment through a systematic review of systematic reviews of comparative studies involving children with or without CHCs and academic attainment. We extracted results from any studies that tested whether school absence mediated the association between CHCs and academic attainment.

Results

We identified 27 systematic reviews which included 441 unique studies of 7, 549, 267 children from 47 jurisdictions. Reviews either covered CHCs generally or were condition-specific (e.g., chronic pain, depression, or asthma). Whereas reviews found an association between a range of CHCs (CHCs generally, cystic fibrosis, hemophilia A, end-stage renal disease (pre-transplant), end-stage kidney disease (pre-transplant), spina bifida, congenital heart disease, orofacial clefts, mental disorders, depression, and chronic pain) and academic attainment, and though it was widely hypothesized that absence was a mediator in these associations, only 7 of 441 studies tested this, and all findings show no evidence of absence mediation.

Conclusion

CHCs are associated with lower academic attainment, but we found limited evidence of whether school absence mediates this association. Policies that focus solely on reducing school absence, without adequate additional support, are unlikely to benefit children with CHCs.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=285031, identifier: CRD42021285031.

Associations between sugar-sweetened beverages before and during pregnancy and offspring overweight/obesity in Japanese women: the TMM BirThree Cohort Study

OBJECTIVE

The association between high sugar-sweetened beverages (SSB) intake during pregnancy and offspring overweight/obesity has been reported only from Western countries. The objective of this study was to examine the association between SSB intake before and during pregnancy and offspring overweight/obesity among Japanese women.

DESIGN

Japanese prospective birth cohort study.

SETTING

We analysed mother-offspring pairs who participated in the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study from 2013 to 2017. SSB intake during pregnancy was evaluated using the FFQ and classified into three groups: none (0 g/d), medium (<195 g/d) and high (>195 g/d). Overweight or obesity at 1 year of age in offspring was defined as having a BMI Z-score greater than 2 sd, calculated based on the BMI reference data for Japanese children. Multiple logistic regression analyses were performed to examine the associations between SSB intake before and during pregnancy and offspring overweight/obesity, after adjusting for covariates.

PARTICIPANTS

Japanese mother-offspring pairs (n 7114).

RESULTS

The overweight/obesity rate of the offspring was 8·8 %. Pregnant women with a high intake of SSB in early to mid-pregnancy had a higher risk of overweight/obesity in their offspring compared with those who did not; the OR was 1·52 (95 % CI (1·09, 2·12)).

CONCLUSIONS

High SSB intake in early to mid-pregnancy was associated with an increased risk of offspring overweight/obesity at 1 year of age.

Mediators of the association between childhood body mass index and educational attainment: Analysis of a UK prospective cohort study

BACKGROUND

Higher body mass index (BMI) in childhood is associated with lower academic achievement.

OBJECTIVE

To explore potential pathways linking childhood BMI with educational attainment.

METHODS

Using data from the Avon Longitudinal Study of Parents and Children prospective cohort study (N = 6949), we assessed the association between BMI z-scores at 11.7 years and educational attainment at 16 (General Certificate of Secondary Education [GCSE] results). Depressive symptoms, externalizing behaviours, bullying and school enjoyment were considered as potential mediators. Mediators were examined individually and jointly using sequential causal mediation.

RESULTS

Higher BMI z-scores were associated with lower GCSE scores (females β = -3.47 95% CI -5.54, -1.41 males β = -4.33 95% CI -6.73, -1.94). Together, bullying, externalizing symptoms, depressive symptoms and school enjoyment mediated 41.9% of this association in females, and 23.3% in males. In males, evidence for mediation was weak (confidence intervals for all indirect effects spanned the null). In both females and males, most of the mediation was driven by externalizing symptoms.

CONCLUSIONS

The detrimental effect of higher BMI on educational attainment appears to be partly explained by externalizing behaviours, particularly in females. Interventions to support behavioural problems may help the academic achievement of children with a higher body weight.

Longitudinal weight status and academic achievement in elementary schoolchildren in the United States

BACKGROUND/OBJECTIVES

Childhood overweight and obesity have a well-established negative impact on children's health. Overweight and obesity might also negatively impact children's academic performance, but existing literature on this association is inconclusive. This study uses a longitudinal design in a large, diverse elementary school sample to rigorously test the association between longitudinal weight status and academic achievement. Analyses also investigate modification by sex, race/ethnicity, and cardiorespiratory fitness (CRF).

SUBJECTS/METHODS

In a large suburban school district in the United States, 4936 Grade 4 students were recruited. Demographic, course grade, and standardized test data were collected from school records for Grades 3-5, and body mass index and CRF were assessed each year. Students wore accelerometers during the school day for up to 15 days across three semesters (Grade 4 Fall and Spring, Grade 5 Fall) to objectively measure physical activity. Multiple imputation addressed missing data and multilevel analyses controlled for student demographics and clustering within schools.

RESULTS

Unadjusted multilevel models found small negative associations between persistent obesity and course grades and standardized test scores, but these associations largely disappeared when controlling for demographic characteristics. Residual associations for math and writing course grades were attenuated when controlling for CRF, though some marginal negative associations for math and writing remained for students who developed obesity during follow-up. There was also evidence of marginal negative associations with course grades for students who developed overweight/obesity. There was no evidence of modification by sex or race/ethnicity.

CONCLUSIONS

Results suggest very small associations between weight status and academic achievement that were largely explained by sociodemographic factors and CRF. Evidence of an association between weight status and achievement was stronger among students who developed overweight/obesity. Interventions promoting healthy weight and high CRF remain critical for schools given the link between student health and achievement.

Longitudinal associations between weight status and academic achievement in primary school children

BACKGROUND

Evidence for longitudinal associations between childhood weight status and academic achievement remains unclear due to considerable heterogeneity in study design, measures of academic achievement and appropriate categorization of weight status.

OBJECTIVE

To examine longitudinal associations between childhood weight status (underweight, healthy weight, overweight/obese) and academic achievement in the transition from preschool to primary (elementary) school among Australian school children.

METHODS

Data were from the Healthy Active Preschool and Primary Years study. Height and weight, for calculating BMI were measured at baseline (preschool age 3-5 years; 2008/9) and follow-up (primary school age 6-8 years; 2011/12). Academic achievement was measured at age 9 years.

RESULTS

No associations between BMI z-score or weight category in the preschool years and later NAPLAN scores were found for boys. For girls, having a higher BMI z-score (B = -13.68, 95%CI: -26.61, -0.76) and being affected by overweight (B = -33.57, 95%CI: -61.50, -5.24) in preschool was associated with lower language scores. Remaining affected by overweight from preschool to primary school was associated with lower numeracy (B = -25.03, 95%CI: -49.74, -0.33), spelling (B = -33.5, 95%CI: -63.43, -3.58), language (B = -37.89, 95%CI: -72.75, -3.03) and total achievement scores (B = -24.24, 95%CI: -44.85, -3.63) among girls. For boys, becoming affected by overweight was associated with lower spelling (B = -38.76, 95%CI: -73.59, -3.93) and total achievement scores (B = -27.70, 95%CI: -54.81, -0.58).

CONCLUSIONS

Associations between being affected by overweight/obesity and poorer academic achievement were more pronounced in girls than boys, indicating potentially inequitable impacts of excess weight and highlighting the greater need for intervention among girls. However, stronger study designs are needed to confirm our findings.

Physical fitness mediates the inverse association between fatness indicators and academic achievement, despite the school vulnerability of adolescents—The Cogni-Action Project

Objective

This study aims to determine the mediating role of physical fitness in the relationship between fatness indicators and academic achievement, exploring the influence of school vulnerability.

Methods

A total of 1,296 Chilean adolescents (aged 10 to 14 years; 50% girls) participated in this study. The global fitness score (GFS) was obtained by adding the three main components of the ALPHA fitness test: cardiorespiratory fitness (CRF), muscular fitness (MF), and speed/agility fitness (SAF). CRF was evaluated through the 20 m shuttle run test; MF by upper and lower limb strength tests; and SAF by the 4 × 10 shuttle run test. BMIz and WHtR were evaluated as general (unspecific) and central (specific) fatness indicators. Academic achievement was established through grades in math, language, and science and their average scores. Multiple mediation analyses were performed according to two models, adjusted for sex, maturity, and schools (model 1), and in model 2, the school vulnerability index (SVI) was added. The SVI is an important proxy of socioeconomic status at the school level, and it was categorized as high-, mid-, or low-SVI. Mediation percentages were calculated, and confidence intervals (bootstrapping) were used to establish significant findings.

Results

CRF, SAF, and GFS mediate the relationship between fatness indicators and academic achievement, both partially and totally (ranging from 12.7 to 59.2%). However, MF did not show any mediation effect. After controlling for SVI, CRF, and GFS, mediation changed from partial to total in the associations between math and science with WHtR. Although SAF contributed to GFS mediation, CRF seems to have the most significant mediation role for all academic achievements, regardless of SVI and the fat indicator studied.

Conclusion

A higher level of general physical fitness, especially CRF, significantly mediates the detrimental influence of fatness on the academic achievement of schoolchildren. This study suggests that physical fitness plays a relevant role in academic and public health, considering the high prevalence and detrimental influence of obesity and school vulnerability in children and adolescents.

Guidelines for treating child and adolescent obesity: A systematic review

Obesity is a chronic disease that compromises the physical and mental health of an increasing proportion of children globally. In high-income countries, prevalence of paediatric obesity is increasing faster in those from marginalised populations such as low-income households, suggesting the disease as one that is largely systemic. Appropriate treatment should be prioritised in these settings to prevent the development of complications and co-morbidities and manage those that already exist. An array of clinical practice guidelines are available for managing overweight and obesity in children and adolescents, but no systematic review has yet compared their quality or synthesised their recommendations. We aimed to narratively review clinical practice guidelines published in English for treating child and adolescent obesity, to identify the highest quality guidelines, and assess similarities, conflicts, and gaps in recommendations. We systematically searched academic databases and grey literature for guidelines published. We used the AGREE II tool to assess the quality, and identified nine high quality guidelines for inclusion in a narrative review of recommendations. Guidelines predominantly recommended the delivery of multi-component behaviour-change interventions aimed at improving nutrition and physical activity. Treatment outcomes were generally focussed on weight, with less emphasis on managing complications or improving quality-of-life. There was no evidence-based consensus on the best mode of delivery, setting, or treatment format. The guidelines rarely included recommendations for addressing the practical or social barriers to behaviour change, such as cooking skills or supervised physical activity. There is insufficient evidence to evaluate pharmaceutical and surgical interventions in children, and these were generally not recommended. It should be noted that this review addressed documents published in English only, and therefore the included guidelines were applicable predominantly to high-resource settings.

Perceived teacher's support and engagement among students with obesity in physical education: The mediating role of basic psychological needs and autonomous motivation

Grounded in self-determination theory, this cross-sectional study aims to explore the multiple mediating roles of perceived teachers' support for students with obesity and their engagement in physical education. The study included 322 Chinese high school students with obesity (mean age, 16.84 [±0.147] years; 219 [68%] male, 103 [32%] female). Mplus 8.3 software was used to test the multiple mediating effects. After controlling for grade and gender, teacher support was found to neither directly affect students' engagement nor directly stimulate their autonomous motivation; however, it could affect their engagement through the two pathways of 1) basic psychological needs and 2) the chain mediation of basic psychological needs and autonomous motivation. Results suggest that not all teacher support, but only teacher support meeting students' basic psychological needs, can promote engagement in PE by students with obesity. Future research should explore strategies according to the physical and mental characteristics of students with obesity, to enrich and innovate the theoretical system of teacher support in physical education. Furthermore, teacher support interventions to promote engagement among students with obesity should be developed.

Effect of Obesity on Arithmetic Processing in Preteens With High and Low Math Skills: An Event-Related Potentials Study

Preadolescence is an important period for the consolidation of certain arithmetic facts, and the development of problem-solving strategies. Obese subjects seem to have poorer academic performance in math than their normal-weight peers, suggesting a negative effect of obesity on math skills in critical developmental periods. To test this hypothesis, event-related potentials (ERPs) were collected during a delayed-verification math task using simple addition and subtraction problems in obese [above 95th body mass index (BMI) percentile] and non-obese (between 5th and 90th BMI percentile) preteens with different levels of math skill; thirty-one with low math skills (14 obese, mean BMI = 26.40, 9.79 years old; 17 non-obese, BMI = 17.45, 9.76 years old) and thirty-one with high math skills (15 obese, BMI = 26.90, 9.60 years old; 16 non-obese, BMI = 17.13, 9.63 years old). No significant differences between weight groups were observed in task accuracy regardless of their mathematical skill level. For ERPs, electrophysiological differences were found only in the subtraction condition; participants with obesity showed an electrophysiologic pattern associated with a reduced ability to allocate attention resources regardless of their math skill level, these differences were characterized by longer P300 latency than their normal-weight peers. Moreover, the participants with obesity with high math skills displayed hypoactivity in left superior parietal lobule compared with their normal-weight peers. Additionally, obese preteens with low math skills displayed smaller arithmetic N400 amplitude than non-obese participants, reflecting difficulties in retrieving visual, semantic, and lexical information about numbers. We conclude that participants with obesity are less able than their normal-weight peers to deploy their attention regardless of their behavioral performance, which seems to have a greater effect on obese participants with low math skills because they also show problems in the retrieval of solutions from working memory, resulting in a delay in the development of mathematical skills.

Links between obesity, weight stigma and learning in adolescence: a qualitative study

BACKGROUND

Educational attainment is a key social determinant of health. Health and education are linked by multiple pathways, many of which are not well understood. One such pathway is the association between being above a healthy weight and lower academic achievement. While various explanations have been put forward to explain this relationship, evidence for causal pathways is sparse and unclear. This study addresses that evidence gap.

METHODS

We interviewed 19 adults (late 20s; 14 female, 5 male) and one young person (14 years, male) from the UK in 2019/2020. Participants were recruited from the ALSPAC 1990s birth cohort, sampled to ensure diversity in socio-economic status and educational attainment, and a community-based weight management group for young people. Interviews focused on experiences of being above a healthy weight during secondary school and how this may have affected their learning and achievement. Interviews were face-to-face, digitally recorded, and transcribed verbatim. We analysed the data thematically.

RESULTS

We identified key pathways through which higher body weight may negatively impact educational performance and showed how these are linked within a novel theoretical model. Because larger body size is highly stigmatised, participants engaged in different strategies to minimise their exposure to negative attention. Participants sought to increase their social acceptance or become less socially visible (or a combination of both). A minority navigated this successfully; they often had many friends (or the 'right' friends), experienced little or no bullying at school and weight appeared to have little effect on their achievement at school. For most however, the behaviours resulting from these strategies (e.g. disruptive behaviour, truanting, not working hard) or the physical, social or mental impacts of their school experiences (e.g. hungry, tired, self-conscious, depressed) made it difficult to concentrate and/or participate in class, which in turn affected how teachers viewed them.

CONCLUSIONS

Action to combat weight stigma, both within schools and in wider society, is urgently required to help address these educational disparities that in turn can impact health in later life.

Food addiction and weight in students with high academic performance

OBJECTIVE

The purpose of this study was to analyse the relationships between food addiction (FA), anthropometric characteristics and academic performance.

DESIGN

The average age (sd) of the participants was 17·5 (sd 2·7) years (64·1 % female). Each study participant indicated their sex, height, weight and academic performance and completed the Yale Food Addiction Scale.

SETTING

Syktyvkar, Kirov, Tyumen, Yekaterinburg, Russia; Aizawl, India.

PARTICIPANTS

The study involved 3426 people.

RESULTS

FA was found in 8·7 % of participants from Russia and 14·6 % from India. In schoolchildren but not in university students, high academic performance was associated with a higher incidence rate of FA detection (OR = 1·16, 95 % CI 1·07, 1·26) and a lower BMI (OR = 0·72, 95 % CI 0·56, 0·94).

CONCLUSIONS

These data showed an increased incidence rate of FA detection in adolescents with high academic performance.

The Role of Chronic Physical Activity in Alleviating the Detrimental Relationship of Childhood Obesity on Brain and Cognition

Childhood obesity and its negative relation with children’s brain health has become a growing health concern. Over the last decade, literature has indicated that physical activity attenuates cognitive impairment associated with obesity and excess adiposity in children. However, there is no comprehensive review that considers the extent to which these factors affect different domains of cognition. This narrative review comprehensively summarizes behavioral, neuroimaging, and neuroelectric findings associated with chronic physical activity and fitness on brain and cognition in childhood obesity. Based on the literature reviewed, increased adiposity has a demonstrated relationship with neurocognitive health via mechanisms triggered by central inflammation and insulin resistance, with the most pronounced decrements observed for cognitive domains that are prefrontal- and hippocampal-dependent. Fortunately, physical activity, especially interventions enhancing aerobic fitness and motor coordination, have demonstrated efficacy for attenuating the negative effects of obesity across different subdomains of structural and functional brain imaging, cognition, and multiple academic outcomes in children with overweight or obesity. Such mitigating effects may be accounted for by attenuated central inflammation, improved insulin sensitivity, and increased expression of neurotrophic factors. Lastly, individual differences appear to play a role in this relationship, as the manipulation of physical activity characteristics, the employment of a wide array of cognitive and academic measures, the inclusion of different adiposity measures that are sensitive to neurocognitive function, and the utilization of an inter-disciplinary approach have been found to influence the relationship between physical activity and excess adiposity on brain and cognition.

Is earlier obesity associated with poorer executive functioning later in childhood? Findings from the Millennium Cohort Study

BACKGROUND

Children affected with overweight or obesity have been associated with having lower educational achievement compared to peers who are non-overweight/obese. One of the drivers of this association could be a link between obesity and poorer executive function. Evidence is limited to small, cross-sectional studies which lack adjustment for important common causes.

OBJECTIVE

We investigate the association between weight status and executive function longitudinally in mid-childhood, accounting for potential common causes.

METHODS

Linear regression analyses were conducted to examine associations between weight status between 5 and 7 years and executive functioning at 11 years in members of the Millennium Cohort Study (n = 7739), accounting for a wide range of potential common causes. Age- and sex-specific International Obesity Taskforce cut-points for body mass index (BMI) were used. Executive function, including decision-making, impulsivity and spatial working memory, was assessed using the Cambridge Neuropsychological Test Automated Battery.

RESULTS

There were no unadjusted associations between weight status and decision-making or impulsivity. After adjustment for all potential common causes, there was a lack of consistent evidence to support an association between persistent obesity (including overweight) between 5 and 7 years and spatial working memory task at 11 years.

CONCLUSIONS

We found little evidence that poorer spatial working memory contributes to the association of children with obesity having lower educational achievement.

Effect of obesity on inhibitory control in preadolescents during stop-signal task. An event-related potentials study

Preadolescence is a period in which structural and functional changes occur in brain network reorganization that relate to the development of executive control functions, particularly in the areas of attention and cognitive inhibition. Obesity has been associated with a deficit in executive functions and behavioral and electrophysiological differences using the go/no-go task (proactive inhibition), but no study has assessed brain-electrical activity using the stop-signal task (reactive inhibition) in this population. Therefore, we hypothesized that obese preadolescents would show less efficiency in reactive inhibition than their same-age non-obese peers. To test this hypothesis, event-related potentials (ERPs) were collected during a stop-signal task and compared between 27 obese preadolescents (mean BMI = 25.9; 9.65 years old) and 29 normal-weight preadolescents (mean BMI = 17.5; 9.60 years old). No significant differences between groups were observed in behavioral responses. As for ERPs, the obese group had an electrophysiological pattern associated with less efficient conflict monitoring during the "no-go" condition (i.e., less modulation of N200 latency based on the experimental condition), differences in attentional allocation in the "go" condition (less modulation of P300a latency based on experimental condition), and difficulties in rule retrieval from working memory associated with the trial-type in both experimental conditions (smaller P300b amplitude). We conclude that obese preadolescents displayed less ability to modulate conflict-monitoring in the "no-go" condition and attention allocation in the "go" condition, evidencing differences between groups in the development of attention and inhibitory control.

Kindergarten Obesity and Academic Achievement: The Mediating Role of Weight Bias

This study draws the attention towards the importance of reducing weight discrimination against children for their educational success, as an issue of social justice. We investigate the consequences of early-onset obesity identifying the mediating mechanisms in the relationship between childhood obesity and academic achievement. To do so, we employ the Early Childhood Longitudinal Study-Kindergarten Cohort (kindergarten to fifth grade) in the US (ECLS-K: 2011) and apply a parallel process latent growth model with a combination of quasi-experiments and econometrics. The results of this study suggest that teachers may serve as a significant source of weight bias, especially for girls (B = -0.09, 95% BC CI [-2.37 to -0.46]).

Physical fitness in preschool children in relation to later body composition at first grade in school

BACKGROUND

This study aimed to investigate whether better physical fitness in kindergarten predicts later healthier body composition in first grade at school.

METHODS

Body composition was assessed by skinfold thickness measurements. Physical fitness tests included 20 m shuttle run test, handgrip strength test, standing long jump test, 4x10 m shuttle run test as part of PREFIT fitness test battery, and one-leg stance test from EUROFIT test battery. The participants of this study were 147 Estonian children (51% boys) aged 6-8 years, who were measured in the transition from kindergarten to school.

RESULTS

After adjusting for maternal body mass index, educational attainment, child's sex, age at the measurements, greater cardiovascular and motor fitness, relative lower body strength, static balance at 6.6 yr were associated with lower fat mass index, fat mass percentage at 12-month follow-up. The relative lower body strength above the median at 6.6 yr were related to lower fat mass index and fat mass percentage at 12-month follow-up, while the static balance test results demonstrated the opposite associations. Improvements in the 4x10 m shuttle run test results during the 12-month follow-up period were associated with the most beneficial changes in body composition status, such as increases in fat-free mass index and decreases in fat mass index, fat mass percentage, waist-to-height ratio after adjusting for maternal body mass index, educational attainment, child's sex, age, at the measurements and baseline values of exposures.

CONCLUSION

Better physical fitness tests results at 6.6 yr in kindergarten generally predicted lower body fat parameters in children at 7.6 yr in first grade at school.

Common health conditions in childhood and adolescence, school absence, and educational attainment: Mendelian randomization study

Good health is positively related to children's educational outcomes, but relationships may not be causal. Demonstrating a causal influence would strongly support childhood and adolescent health as important for education policy. We applied genetic causal inference methods to assess the causal relationship of common health conditions at age 10 (primary/elementary school) and 13 (mid-secondary/mid-high school) with educational attainment at 16 and school absence at 14-16. Participants were 6113 children from the Avon Longitudinal Study of Parents and Children (ALSPAC). Exposures were symptoms of attention-deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD), depression, asthma, migraines and BMI. Genetic liability for these conditions and BMI was indexed by polygenic scores. In non-genetic, multivariate-adjusted models, all health conditions except asthma and migraines were associated with poorer attainment and greater school absence. School absence substantially mediated effects of BMI (39.9% for BMI at 13) and migraines (72.0% at 10), on attainment with more modest mediation for emotional and neurodevelopmental conditions. In genetic models, a unit increase in standardized BMI at 10 predicted a 0.19 S.D. decrease (95% CI: 0.11, 0.28) in attainment at 16, equivalent to around a 1/3 grade lower in all subjects, and 8.7% more school absence (95% CI:1.8%,16.1%). Associations were similar at 13. Genetic liability for ADHD predicted lower attainment but not more absence. Triangulation across multiple approaches supports a causal, negative influence on educational outcomes of BMI and ADHD, but not of ASD, depression, asthma or migraine. Higher BMI in childhood and adolescence may causally impair educational outcomes.

The impact of childhood obesity on human capital in high-income countries: A systematic review

Current evidence of the impact of childhood obesity on human capital development does not point in a consistent direction, and its interpretation is challenging. We carried out a systematic review of studies from high-income countries that used robust causal inference approaches to assess the impact of childhood overweight and obesity on outcomes typically linked to human capital development in economics. Global Health, Medline and EconLit were used to search for peer-reviewed papers. Three reviewers independently assessed study quality using the Newcastle-Ottawa Scale. Nineteen papers representing 22 studies met the inclusion criteria. Included studies were categorized based on three components of human capital: cognitive performance (n = 18), measured through test scores; educational attainment (n = 3), through grade progression and college completion; and labour market outcomes (n = 1), through wages. We find that childhood overweight and obesity hinder education outcomes, with effects mostly observed at older ages of exposure measurement (12+ years). Girls with overweight and obesity experienced larger negative effects and more often than boys. Future research should elucidate the pathways through which childhood obesity impacts human capital development, to support policies that may mitigate those impacts, thus averting social costs that are currently widespread, increasing and unaccounted for.

Weight transitions and psychosocial factors: A longitudinal cohort study of Finnish primary school children with overweight

•

Children most probably stayed in their initial weight category.

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Probabilities of transitioning across weight categories differ between genders.

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Girls of nuclear families transition to obesity at a lower rate than their peers.

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Experiences of crises and bullying are related to obesity development among boys.

•

Multistate models are useful for analyzing childhood obesity development.

For targeted prevention and treatment of childhood obesity, primary health care needs methods to identify children potentially developing obesity. The objectives of this study were to examine transitions across weight categories and their association with psychosocial family- and school-related factors, data on which were retrieved from health records. This longitudinal cohort study comprised 507 Finnish children with overweight, identified from a random sample of 2000 sixth graders in Helsinki in 2013. We applied Markov multistate models to analyze the transition rates over six primary school years between BMI SDS categories of normal weight, overweight and obesity, as assessed by Finnish BMI-for-age reference, and to examine relations between transition rates and family- and school-related factors. Among 3116 pairs of consecutive growth measurements from 225 girls and 282 boys aged 6–14, 719 transitions from weight category to another occurred. The highest 1-year probabilities were 0.76 for girls to stay in overweight and 0.80 for boys to stay in obesity. Transitions from normal weight to overweight and from obesity to overweight were more probable than vice versa. Transitions from overweight into obesity were among girls associated with older age (HR 2.63) and divorced or single parents (HR 2.29), as well as among boys with experiences of crises (HR 2.40) and being bullied (HR 1.66). Factors identifiable in school health care and associated with the probability of transition towards obesity should be considered when planning individual support and intervention programs.

Weight Stigma in Youth: Prevalence, Consequences, and Considerations for Clinical Practice

PURPOSE OF REVIEW

This review summarizes recent evidence on weight stigma experienced by youth with overweight or obesity. We examine the prevalence and sources of weight-based victimization targeting youth, consequences of these stigmatizing experiences for their psychological and physical health, and considerations for addressing weight stigma in clinical practice and pediatric care.

RECENT FINDINGS

Weight stigma is highly prevalent among youth with high body weight, who are targets of weight-based victimization from peers, parents, and teachers. These experiences place youth at risk for psychological distress (primarily depressive symptoms, low self-esteem, and suicidal ideation), worse social and academic outcomes, and adverse physical health consequences including maladaptive eating behaviors, lower physical activity, substance use, and weight gain. Healthcare professionals and clinicians have important roles to play in efforts to help reduce weight stigma and support youth with obesity. Fundamental to these efforts is the use of supportive, compassionate, and non-stigmatizing communication with youth and their families.

Differences in educational attainment between obese and non-obese Kuwaiti female university students

Individuals with obesity tend to perform less well than their non-obese peers in tertiary education, but there is little evidence from non-Western countries and recent studies. The present study aimed to test whether academic attainment differed between female undergraduates with obesity (defined by body mass index (BMI)), and those who were non-obese in Kuwait, a country with very high obesity prevalence. In 400 female Kuwaiti first- and second-year Social Science students (mean age 18⋅0, sd 0⋅6 years), educational attainment was defined as the Grade Point Average (GPA) across all subjects (from 1⋅00 to 4⋅00). The mean GPA (2⋅51, sd 0⋅53) among students defined as obese by the BMI (n 163) was significantly lower than among the students defined as non-obese by the BMI (n 237; 2⋅80, sd 0⋅63; P < 0⋅001), and those defined as obese were more likely to be in the lowest quartile for the GPA (OR 3⋅03; 95% CI 1⋅90, 4⋅85), independent of socio-economic status. Similar differences were observed between students defined as having high versus normal body fatness. Female undergraduates in Kuwait with obesity have lower academic attainment than their non-obese peers, and universities should consider measures to mitigate reduced attainment among their female undergraduates.

The Associations between Childhood Obesity, Academic Performance, and Perception of Teachers: From Kindergarten to Fifth Grade

Background: Obesity is weakly associated with negative academic achievement among school-aged children. The purpose of this study is to demonstrate the relationships between reading/mathematics scores (objective) and teachers' perception of learning ability (subjective) and childhood obesity-from kindergarten to fifth grade. Methods: This study examined a longitudinal study of a nationally representative sample of 18,174 children who were enrolled in kindergarten in 2010 in the United States (ECLS-K:2011). Weighted multiple logistic regression models were used to examine the associations between objective scores, subjective scores, and obesity (vs. healthy-weight children). Results: In the crude analyses, obesity was negatively associated with achieving above-median reading and mathematics scores. After adjusting for sex, race/ethnicity, age, and socioeconomic status (SES), the association weakened but was still present. Children with obesity were less likely to achieve above-median reading and mathematics scores than their healthy-weight peers (odds ratio [OR] 0.77 and 0.86 for reading; OR 0.85, 0.67, 0.79, 0.82, and 0.75 for mathematics). Similarly, teachers reported that children with obesity did not have Approaches to Learning and Attentional Focusing as good as their healthy-weight peers regardless of their objective test scores and SES (OR 0.82, 0.80, 0.78, 0.69, and 0.77 for Approaches to Learning; OR 0.80, 0.81, 0.83, 0.82, 0.80, and 0.74 for Attentional Focusing). Conclusions: Obesity during elementary school years is negatively associated with both objective and subjective measures of academic performance. Further studies are needed to understand if the connection is stemming from behavioral issues of children, weight-based bias of teachers, or both.

The mediating effect of physical fitness on long term influences of overweight in primary school girls' academic performance

BACKGROUND

Overweight and obesity contribute to multiple health risks in children, while also impacting negatively on educational performance. Physical fitness can impact outcomes beyond health related measures therefore it can play a mediating role in combating the negative effects of being overweight.

METHODS

One hundred and seventy-two primary school girls aged 6-13 years old from the North West Province of South Africa formed part of this random stratified longitudinal research design in which three follow-up measurements took place over seven years. Body Mass Index was used to compile obesity profiles, while the progressive aerobic cardiovascular endurance run (PACER) was used to determine cardiovascular fitness. Academic school achievements for grades 1, grade 4 and grade 7, as well as national and provincial values were correlated with academic performance. Data were analyzed by a repeated measure over time ANOVA as well using a latent growth curve model from the structural equation modelling framework (SEM).

RESULTS

No differences (P>0.05) were found in the academic performance of obese and normal weight girls, although obese girls showed poorer physical fitness values (P<0.05). The SEM model was a good fit for all requirements (RMSEA, 0.60; CMIN DF, 2.837; CFI, 0.966). VO<inf>2</inf>max had a standardized indirect mediation effect (-132) while body composition showing a standardized direct effect (0.183) with academic achievement. Physical fitness showed a mediation effect with regard to obesity and academic achievement in grade 7 girls.

CONCLUSIONS

Although the academic performance of obese girls did not show impairment before the age of 12 years, physical fitness had a reversible effect on relationships between obesity and academic achievement. This substantial influence of physical fitness should be used strategically in preventive intervention programs necessary to enhance cognitive functioning, academic performance and brain health among overweight children.

Changes in body mass index and risk of adolescent psychopathology: a longitudinal cohort study

BACKGROUND.

Abnormal body mass index (BMI) has been associated with development of psychopathology. This association in children is well documented, for both overweight and underweight children. However, the association between change in BMI and the development of psychopathology has been less investigated.

AIM.

To investigate the association between change in BMI between childhood and adolescence and psychopathology in adolescence.

METHODS.

Data from the Growing Up in Ireland cohort were used. We investigated the '98 cohort (also known as the child cohort) at age 9/13. BMI, defined using internationally recognised definitions as underweight, healthy or overweight, was used as the exposure, and abnormal Strength and Difficulties Questionnaire scores were used as the outcome. Logistic regression was undertaken for the analysis. All analyses were adjusted for confounders.

RESULTS.

A change to overweight from healthy BMI was significantly associated with increased risk of psychopathology (adjusted OR 1.66; 95% CI 1.19-2.32). Both change from underweight to healthy (adjusted OR 0.12; 95% CI 0.03-0.43) or from overweight to healthy (adjusted OR 0.47; 95% CI 0.79-0.8) was associated with a significantly reduced risk of developing psychopathology.

DISCUSSION.

As a child's BMI returns to within the healthy range, their risk of adolescent psychopathology is reduced. Interventions to restore healthy BMI, in both underweight and overweight, children may reduce their risk of adolescent psychopathology.

An Overview on the Associations between Health Behaviors and Brain Health in Children and Adolescents with Special Reference to Diet Quality

Unhealthy diet has been associated with overweight, obesity, increased cardiometabolic risk, and recently, to impaired cognition and academic performance. The aim of this review is to provide an overview of the associations between health behaviors and cognition and academic achievement in children and adolescents under 18 years of age with a special reference to diet quality. Dietary patterns with a low consumption of fish, fruits, and vegetables, and high in fast food, sausages, and soft drinks have been linked to poor cognition and academic achievement. The studies on the associations between the high intake of saturated fat and red meat and low intake of fiber and high-fiber grain products with cognition are limited. The available evidence and physiological mechanisms suggest that diet may have direct, indirect, and synergistic effects on brain and cognition with physical activity, sedentary behaviors, cardiometabolic health, and sleep, but the associations have been modest. Therefore, integrating a healthy diet, physically active lifestyle, and adequate sleep may provide optimal circumstances for brain development and learning. We conclude that most of the existing literature is contained in cross-sectional studies, which therefore highlights the need for longitudinal and intervention studies on the effects of diet, physical activity, sedentary behavior, and sleep on cognition and academic performance.

Obesity is associated with poor working memory in women, not men: Findings from a nationally representative dataset of U.S. adults

A growing body of research has linked obesity to lower working memory performance. However, sex differences are often found in associations between obesity and cognition, and little work has examined potential sex differences in the association between obesity and working memory. To address this issue, the present research uses data from Wave IV of The National Longitudinal Study of Adolescent to Adult Health (N = 4,769, mean age = 29) to examine whether sex moderated the association between excess weight and working memory. As expected, we found that obesity was associated with poorer working memory, but-importantly-this association was exclusively seen in women, not men. These results held when treating BMI as a continuous or categorical variable (e.g., normal weight, obese), as well as with and without controlling for covariates. The present results therefore indicate that the association between obesity and poorer working memory performance may be sex-dependent. These results suggest that interventions targeted at reducing obesity should be tailored to an individual's sex, as adherence to these interventions often requires working memory.

Associations of Cell Phone Use and Screen Viewing with Overweight in Children

Background: Effects of using mobile devices on childhood obesity have not been well studied. We aimed to ascertain whether cell phone use and screen viewing are associated with excess body weight in a cross-sectional study of Japanese school children. Methods: Subjects were 3141 students, ages 6 to 7 years, who participated in the Hekinan Children's Study conducted during 2011-2015. Participants were asked to submit a parent-administered questionnaire on child and parent demographics, health status, and lifestyles, including cell phone use and screen time. Heights and weights were measured at the schools. Being overweight was defined according to the cutoff point for children specified by the Extended International Obesity Task Force. Among 2596 analytic children, the odds ratios (ORs) for being overweight were estimated according to cell phone use, time spent watching television, and time spent on games and computers using the logistic regression models. Analyses were conducted after adjustments for potential confounders, including dietary intake, physical activities, sleep duration, and quality of sleep. Results: After multivariate adjustments, cell phone users were found to have an OR of 1.74 for being overweight compared with nonusers. Cell phone use of longer duration was associated with higher risk of being overweight (trend p = 0.018). Time spent watching television was positively associated with the risk of being overweight (trend p = 0.003). Conclusions: Just as earlier studies have shown for television viewing, cell phone use might be a risk factor related to being overweight among children.

Weight Bias in Educational Settings: a Systematic Review

PURPOSE

To conduct a systematic literature review of empirical peer-reviewed published studies on the prevalence of weight bias among students, pre-service, and in-service teachers and its impact on the educational experiences and health of students from kindergarten to postsecondary settings.

METHODS

Keywords were searched on three main concepts, (i) weight bias/stigma, (ii) obesity/overweight, and (iii) education, within eight databases. Our search yielded 8323 individual records, of which 45 studies satisfied our inclusion criteria.

RESULTS

Most studies were conducted in K-12 school settings (n = 41), were quantitative in design (n = 37), and used student samples (n = 18). Weight bias is prevalent in educational settings, among peers at school as well as pre-service and in-service teachers, and negatively impacts students' health and educational experiences.

CONCLUSION

These results highlighted the impact of weight bias in creating inequity for students with obesity as well as several underexamined areas, such as weight bias in postsecondary settings and attitudes among teachers and pre-service teachers. Innovative strategies to address weight bias in educational settings are needed.

Body weight and academic achievement: The role of weight diversity in urban middle schools

The current study was designed to examine one possible weight stigma-reduction mechanism: school-level weight diversity. It was hypothesized that greater weight diversity among same-sex peers at school would attenuate the negative association between weight and academic achievement. Across 26 urban public middle schools, 5,991 sixth-grade students (52% girls) were included: 12% African American/Black, 14% East/Southeast Asian, 30% Latino, 21% White, and 23% from other specific ethnic groups. Weight diversity was estimated as the likelihood that two randomly selected students would be from different weight categories, using Simpson's index. Standardized achievement test scores and grade point average (GPA) were used to assess academic achievement. Consistent with our contextual moderator hypothesis, high levels of weight diversity at school served a protective function. The negative association between body mass index (BMI) and achievement test scores, as well as GPA (girls only) was nonsignificant at schools with high levels of weight diversity. The study results offer a potential explanation for inconsistent findings regarding body weight and achievement, and a novel methodological approach to capture weight diversity in ways that provide new insights for school-based interventions. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Do changes in weight status affect cognitive function in children and adolescents with obesity? A secondary analysis of a clinical trial

OBJECTIVES

It is unclear whether an association exists between obesity in children/adolescents and cognitive function, and whether the latter can be altered by body mass index (BMI) standard deviation score (SDS) reductions. We aimed to determine whether an association exists between BMI SDS and cognitive function in children/adolescents with obesity engaged in an obesity intervention. Second, we sought to determine if BMI SDS reduction at 12 months was associated with improved cognitive function.

DESIGN

Secondary analysis of a clinical trial.

PARTICIPANTS

Participants (n=69) were recruited from an obesity intervention. Eligible participants (recruited June 2013 to June 2015) were aged 6-16 years, with a BMI ≥98th centile or BMI >91st centile with weight-related comorbidities.

OUTCOME MEASURES

Primary outcome measure was change in BMI SDS from baseline at 12 months. Dependent variables of cognitive functioning and school achievement were assessed at baseline and 12 months, using dependent variables of cognitive functioning (elements of Ravens Standard Progressive Matrices, Wide Range Achievement Test-fourth edition and Wechsler Intelligence Scale for Children-fourth edition).

RESULTS

At baseline, BMI SDS was not associated with all aspects of cognitive function tested (n=69). Reductions in BMI SDS over time did not alter cognitive function overall. However, there was a greater reduction in comprehension standard scores in participants who increased their BMI SDS (adjusted estimated difference -6.1, 95% CI -11.6 to -0.6; p=0.03).

CONCLUSIONS

There were no observed associations between BMI SDS and cognitive function in participants, apart from comprehension in the exploratory analyses, which may have been a random finding. Further studies need to include larger longitudinal cohorts incorporating a wider BMI range at entry to determine whether our findings persist.

TRIAL REGISTRATION NUMBER

ANZCTR12611000862943; Pre-results.

The Efficacy of Preschool Developmental Indicators as a Screen for Early Primary School-Based Literacy Interventions

Literacy success lays the foundation for children's later educational, health, and well-being outcomes. Thus, early identification of literacy need is vital. Using data from New Zealand's national preschool health screening program for fiscal years 2010/2011-2014/2015, demographic and health variables from 255,090 children aged 4 years were related to whether they received a literacy intervention in early primary school. Overall, 20,652 (8.1%) children received an intervention. Time-to-event analysis revealed that all considered variables were significantly related to literacy intervention (all p < .01), but the full model lacked reasonable predictive power for population screening purposes (Harrell's c-statistic = .624; 95% CI [.618, .629]). Including more direct literacy measures in the national screening program is likely needed for improvement.

Patterns of early primary school-based literacy interventions among Pacific children from a nationwide health screening programme of 4 year olds

Literacy success is critical to unlocking a child's potential and enhancing their future wellbeing. Thus, the early identification and redressing of literacy needs is vital. Pacific children have, on average, the lowest literacy achievement levels in New Zealand. However, this population is very diverse. This study sought to determine whether the current national health screening programme of pre-school children could be used as an early detection tool of Pacific children with the greatest literacy needs. Time-to-event analyses of literacy intervention data for Pacific children born in years 2005-2011 were employed. A multivariable Cox proportional hazard model was fitted, and predictive assessment made using training and test datasets. Overall, 59,760 Pacific children were included, with 6,861 (11.5%) receiving at least one literacy intervention. Tongan (hazard ratio [HR]: 1.33; 95% confidence interval [CI]: 1.23, 1.45) and Cook Island Māori (HR: 1.33; 95% CI: 1.21, 1.47) children were more likely to receive an intervention than Samoan children; whereas those children with both Pacific and non-Pacific ethnic identifications were less likely. However, the multivariable model lacked reasonable predictive power (Harrell's c-statistic: 0.592; 95% CI: 0.583, 0.602). Regardless, important Pacific sub-populations emerged who would benefit from targeted literacy intervention or policy implementation.

Cardiorespiratory fitness and academic performance association is mediated by weight status in adolescents: DADOS study

The aim of our study was to examine the mediation effect of weight status on the association between cardiorespiratory fitness (CRF) and academic performance (AP). Two hundred sixty-nine adolescents (140 boys) aged 13.9 ± 0.3 years old from the DADOS study were included in this cross-sectional analysis. CRF was assessed by the 20-m shuttle run test and estimated maximum oxygen uptake was used in the analysis. AP was assessed through the final academic grades and the Science Research Associates Test of Educational Abilities for assessing reasoning, verbal, and numeric abilities. Weight status was assessed by body mass index (kg/m²). Boot-strapped mediation procedures were performed and indirect effects (IE) with confidence intervals (CI) not including zero were considered statistically significant. Mediation analysis revealed that weight status acted as a mediator of the relationship of CRF with reasoning ability (IE = 0.039; CI = 0.001; 0.091) and the final grades in Math (IE = 0.011; CI = 0.002; 0.025), Language (IE = 0.013; CI = 0.004; 0.027), and GPA (IE = 0.011; CI = 0.003; 0.023).

CONCLUSIONS

Our data show that the influence of CRF on academic performance is mediated by weight status in adolescents. We suggest that our data could be considered by educators, families, and policy makers, so that active lifestyles might be promoted when designing programs aimed to improve AP among adolescents. What is Known: • Academic performance is associated with both, cardiorespiratory fitness and weight status. • The role of weight status in the association between cardiorespiratory fitness and academic performance is poorly understood. What is New: • We support the scarce research investigating the mediating role of weight status as mechanism in the association between fitness and academic performance in youth. • Previous knowledge is expanded by suggesting that cardiorespiratory fitness is related to weight status which in turn may positively influence academic performance in adolescents.

Physical activity, diet and other behavioural interventions for improving cognition and school achievement in children and adolescents with obesity or overweight

BACKGROUND

The global prevalence of childhood and adolescent obesity is high. Lifestyle changes towards a healthy diet, increased physical activity and reduced sedentary activities are recommended to prevent and treat obesity. Evidence suggests that changing these health behaviours can benefit cognitive function and school achievement in children and adolescents in general. There are various theoretical mechanisms that suggest that children and adolescents with excessive body fat may benefit particularly from these interventions.

OBJECTIVES

To assess whether lifestyle interventions (in the areas of diet, physical activity, sedentary behaviour and behavioural therapy) improve school achievement, cognitive function (e.g. executive functions) and/or future success in children and adolescents with obesity or overweight, compared with standard care, waiting-list control, no treatment, or an attention placebo control group.

SEARCH METHODS

In February 2017, we searched CENTRAL, MEDLINE and 15 other databases. We also searched two trials registries, reference lists, and handsearched one journal from inception. We also contacted researchers in the field to obtain unpublished data.

SELECTION CRITERIA

We included randomised and quasi-randomised controlled trials (RCTs) of behavioural interventions for weight management in children and adolescents with obesity or overweight. We excluded studies in children and adolescents with medical conditions known to affect weight status, school achievement and cognitive function. We also excluded self- and parent-reported outcomes.

DATA COLLECTION AND ANALYSIS

Four review authors independently selected studies for inclusion. Two review authors extracted data, assessed quality and risks of bias, and evaluated the quality of the evidence using the GRADE approach. We contacted study authors to obtain additional information. We used standard methodological procedures expected by Cochrane. Where the same outcome was assessed across different intervention types, we reported standardised effect sizes for findings from single-study and multiple-study analyses to allow comparison of intervention effects across intervention types. To ease interpretation of the effect size, we also reported the mean difference of effect sizes for single-study outcomes.

MAIN RESULTS

We included 18 studies (59 records) of 2384 children and adolescents with obesity or overweight. Eight studies delivered physical activity interventions, seven studies combined physical activity programmes with healthy lifestyle education, and three studies delivered dietary interventions. We included five RCTs and 13 cluster-RCTs. The studies took place in 10 different countries. Two were carried out in children attending preschool, 11 were conducted in primary/elementary school-aged children, four studies were aimed at adolescents attending secondary/high school and one study included primary/elementary and secondary/high school-aged children. The number of studies included for each outcome was low, with up to only three studies per outcome. The quality of evidence ranged from high to very low and 17 studies had a high risk of bias for at least one item. None of the studies reported data on additional educational support needs and adverse events.Compared to standard practice, analyses of physical activity-only interventions suggested high-quality evidence for improved mean cognitive executive function scores. The mean difference (MD) was 5.00 scale points higher in an after-school exercise group compared to standard practice (95% confidence interval (CI) 0.68 to 9.32; scale mean 100, standard deviation 15; 116 children, 1 study). There was no statistically significant beneficial effect in favour of the intervention for mathematics, reading, or inhibition control. The standardised mean difference (SMD) for mathematics was 0.49 (95% CI -0.04 to 1.01; 2 studies, 255 children, moderate-quality evidence) and for reading was 0.10 (95% CI -0.30 to 0.49; 2 studies, 308 children, moderate-quality evidence). The MD for inhibition control was -1.55 scale points (95% CI -5.85 to 2.75; scale range 0 to 100; SMD -0.15, 95% CI -0.58 to 0.28; 1 study, 84 children, very low-quality evidence). No data were available for average achievement across subjects taught at school.There was no evidence of a beneficial effect of physical activity interventions combined with healthy lifestyle education on average achievement across subjects taught at school, mathematics achievement, reading achievement or inhibition control. The MD for average achievement across subjects taught at school was 6.37 points lower in the intervention group compared to standard practice (95% CI -36.83 to 24.09; scale mean 500, scale SD 70; SMD -0.18, 95% CI -0.93 to 0.58; 1 study, 31 children, low-quality evidence). The effect estimate for mathematics achievement was SMD 0.02 (95% CI -0.19 to 0.22; 3 studies, 384 children, very low-quality evidence), for reading achievement SMD 0.00 (95% CI -0.24 to 0.24; 2 studies, 284 children, low-quality evidence), and for inhibition control SMD -0.67 (95% CI -1.50 to 0.16; 2 studies, 110 children, very low-quality evidence). No data were available for the effect of combined physical activity and healthy lifestyle education on cognitive executive functions.There was a moderate difference in the average achievement across subjects taught at school favouring interventions targeting the improvement of the school food environment compared to standard practice in adolescents with obesity (SMD 0.46, 95% CI 0.25 to 0.66; 2 studies, 382 adolescents, low-quality evidence), but not with overweight. Replacing packed school lunch with a nutrient-rich diet in addition to nutrition education did not improve mathematics (MD -2.18, 95% CI -5.83 to 1.47; scale range 0 to 69; SMD -0.26, 95% CI -0.72 to 0.20; 1 study, 76 children, low-quality evidence) and reading achievement (MD 1.17, 95% CI -4.40 to 6.73; scale range 0 to 108; SMD 0.13, 95% CI -0.35 to 0.61; 1 study, 67 children, low-quality evidence).

AUTHORS' CONCLUSIONS

Despite the large number of childhood and adolescent obesity treatment trials, we were only able to partially assess the impact of obesity treatment interventions on school achievement and cognitive abilities. School and community-based physical activity interventions as part of an obesity prevention or treatment programme can benefit executive functions of children with obesity or overweight specifically. Similarly, school-based dietary interventions may benefit general school achievement in children with obesity. These findings might assist health and education practitioners to make decisions related to promoting physical activity and healthy eating in schools. Future obesity treatment and prevention studies in clinical, school and community settings should consider assessing academic and cognitive as well as physical outcomes.

Physical activity, diet and other behavioural interventions for improving cognition and school achievement in children and adolescents with obesity or overweight

BACKGROUND

The global prevalence of childhood and adolescent obesity is high. Lifestyle changes towards a healthy diet, increased physical activity and reduced sedentary activities are recommended to prevent and treat obesity. Evidence suggests that changing these health behaviours can benefit cognitive function and school achievement in children and adolescents in general. There are various theoretical mechanisms that suggest that children and adolescents with excessive body fat may benefit particularly from these interventions.

OBJECTIVES

To assess whether lifestyle interventions (in the areas of diet, physical activity, sedentary behaviour and behavioural therapy) improve school achievement, cognitive function (e.g. executive functions) and/or future success in children and adolescents with obesity or overweight, compared with standard care, waiting-list control, no treatment, or an attention placebo control group.

SEARCH METHODS

In February 2017, we searched CENTRAL, MEDLINE and 15 other databases. We also searched two trials registries, reference lists, and handsearched one journal from inception. We also contacted researchers in the field to obtain unpublished data.

SELECTION CRITERIA

We included randomised and quasi-randomised controlled trials (RCTs) of behavioural interventions for weight management in children and adolescents with obesity or overweight. We excluded studies in children and adolescents with medical conditions known to affect weight status, school achievement and cognitive function. We also excluded self- and parent-reported outcomes.

DATA COLLECTION AND ANALYSIS

Four review authors independently selected studies for inclusion. Two review authors extracted data, assessed quality and risks of bias, and evaluated the quality of the evidence using the GRADE approach. We contacted study authors to obtain additional information. We used standard methodological procedures expected by Cochrane. Where the same outcome was assessed across different intervention types, we reported standardised effect sizes for findings from single-study and multiple-study analyses to allow comparison of intervention effects across intervention types. To ease interpretation of the effect size, we also reported the mean difference of effect sizes for single-study outcomes.

MAIN RESULTS

We included 18 studies (59 records) of 2384 children and adolescents with obesity or overweight. Eight studies delivered physical activity interventions, seven studies combined physical activity programmes with healthy lifestyle education, and three studies delivered dietary interventions. We included five RCTs and 13 cluster-RCTs. The studies took place in 10 different countries. Two were carried out in children attending preschool, 11 were conducted in primary/elementary school-aged children, four studies were aimed at adolescents attending secondary/high school and one study included primary/elementary and secondary/high school-aged children. The number of studies included for each outcome was low, with up to only three studies per outcome. The quality of evidence ranged from high to very low and 17 studies had a high risk of bias for at least one item. None of the studies reported data on additional educational support needs and adverse events.Compared to standard practice, analyses of physical activity-only interventions suggested high-quality evidence for improved mean cognitive executive function scores. The mean difference (MD) was 5.00 scale points higher in an after-school exercise group compared to standard practice (95% confidence interval (CI) 0.68 to 9.32; scale mean 100, standard deviation 15; 116 children, 1 study). There was no statistically significant beneficial effect in favour of the intervention for mathematics, reading, or inhibition control. The standardised mean difference (SMD) for mathematics was 0.49 (95% CI -0.04 to 1.01; 2 studies, 255 children, moderate-quality evidence) and for reading was 0.10 (95% CI -0.30 to 0.49; 2 studies, 308 children, moderate-quality evidence). The MD for inhibition control was -1.55 scale points (95% CI -5.85 to 2.75; scale range 0 to 100; SMD -0.15, 95% CI -0.58 to 0.28; 1 study, 84 children, very low-quality evidence). No data were available for average achievement across subjects taught at school.There was no evidence of a beneficial effect of physical activity interventions combined with healthy lifestyle education on average achievement across subjects taught at school, mathematics achievement, reading achievement or inhibition control. The MD for average achievement across subjects taught at school was 6.37 points lower in the intervention group compared to standard practice (95% CI -36.83 to 24.09; scale mean 500, scale SD 70; SMD -0.18, 95% CI -0.93 to 0.58; 1 study, 31 children, low-quality evidence). The effect estimate for mathematics achievement was SMD 0.02 (95% CI -0.19 to 0.22; 3 studies, 384 children, very low-quality evidence), for reading achievement SMD 0.00 (95% CI -0.24 to 0.24; 2 studies, 284 children, low-quality evidence), and for inhibition control SMD -0.67 (95% CI -1.50 to 0.16; 2 studies, 110 children, very low-quality evidence). No data were available for the effect of combined physical activity and healthy lifestyle education on cognitive executive functions.There was a moderate difference in the average achievement across subjects taught at school favouring interventions targeting the improvement of the school food environment compared to standard practice in adolescents with obesity (SMD 0.46, 95% CI 0.25 to 0.66; 2 studies, 382 adolescents, low-quality evidence), but not with overweight. Replacing packed school lunch with a nutrient-rich diet in addition to nutrition education did not improve mathematics (MD -2.18, 95% CI -5.83 to 1.47; scale range 0 to 69; SMD -0.26, 95% CI -0.72 to 0.20; 1 study, 76 children, low-quality evidence) and reading achievement (MD 1.17, 95% CI -4.40 to 6.73; scale range 0 to 108; SMD 0.13, 95% CI -0.35 to 0.61; 1 study, 67 children, low-quality evidence).

AUTHORS' CONCLUSIONS

Despite the large number of childhood and adolescent obesity treatment trials, we were only able to partially assess the impact of obesity treatment interventions on school achievement and cognitive abilities. School and community-based physical activity interventions as part of an obesity prevention or treatment programme can benefit executive functions of children with obesity or overweight specifically. Similarly, school-based dietary interventions may benefit general school achievement in children with obesity. These findings might assist health and education practitioners to make decisions related to promoting physical activity and healthy eating in schools. Future obesity treatment and prevention studies in clinical, school and community settings should consider assessing academic and cognitive as well as physical outcomes.