Socioeconomic inequalities in childhood obesity in the United Kingdom: a systematic review of the literature

Effectiveness of interventions to reduce social inequalities of weight status in adolescents: A systematic review and meta-analysis

Many interventions are implemented in the public health context to overcome social inequalities of weight status in adolescents, but their effectiveness is challenged. This study aimed to examine the effectiveness of these interventions with a systematic review and meta-analysis. We systematically searched for reports of randomized control trials and quasi-experimental studies aiming to reduce social inequalities of weight status in adolescents in five electronic databases. The primary outcomes were social inequalities in weight-related outcomes (body mass index [BMI], BMI z score, waist circumference, percent body fat, prevalence of overweight/obesity). Interventions were effective when they reduced social inequalities in at least one weight-related outcome. Meta-analyses involved using random-effects models. The review included 38 publications (33 studies) with interventions mostly targeting disadvantaged adolescents (n = 29 studies), showing effectiveness in half of the studies (n = 19/33, 57.6%). The meta-analysis (27 studies) revealed that targeted interventions significantly reduced BMI z score (β = -0.04 [95% CI -0.08, -0.01]), BMI (β = -0.32 [-0.47, -0.18]), and waist circumference (β = -0.84 [-1.48, -0.21]) but not percent body fat (β = -0.27 [-0.71, 0.17]) or prevalence of overweight/obesity (odds ratio = 1.06 [0.85, 1.31]). This review shows moderate effectiveness of interventions targeting disadvantaged adolescents to reduce social inequalities of weight status. High-quality research with better implementation to reach their full potential is required to strengthen their effectiveness.

Ultraprocessed Food Consumption and Cardiometabolic Risk Factors in Children

Importance

High intake of ultraprocessed foods (UPFs) has been associated with higher cardiometabolic risk in adults; however, the evidence in children is limited.

Objective

To investigate the association between UPF consumption and cardiometabolic risk factors in the Childhood Obesity Risk Assessment Longitudinal Study (CORALS).

Design, Setting, and Participants

This baseline cross-sectional analysis was conducted using the data of CORALS participants recruited between March 22, 2019, and June 30, 2022. Preschool children (aged 3-6 years) were recruited from schools and centers in 7 cities in Spain. Inclusion criteria included informed consent signed by parents or caregivers and having a completed a set of questionnaires about the child's prenatal history at home. Exclusion criteria included low command of Spanish or unstable residence.

Exposure

Energy-adjusted UPF consumption (in grams per day) from food frequency questionnaires and based on the NOVA food classification system.

Main Outcomes and Measures

Age- and sex-specific z scores of adiposity parameters (body mass index [BMI], fat mass index, waist-to-height ratio, and waist circumference) and cardiometabolic parameters (diastolic and systolic blood pressure, fasting plasma glucose, homeostasis model assessment for insulin resistance, high-density and low-density lipoprotein cholesterol, and triglycerides) were estimated using linear regression models.

Results

Of 1509 enrolled CORALS participants, 1426 (mean [SD] age, 5.8 [1.1] years; 698 boys [49.0%]) were included in this study. Mothers of children with high UPF consumption were younger, had a higher BMI, were more likely to have overweight or obesity, and had lower education levels and employment rates. Compared with participants in the lowest tertile of energy-adjusted UPF consumption, those in the highest tertile showed higher z scores of BMI (β coefficient, 0.20; 95% CI, 0.05-0.35), waist circumference (β coefficient, 0.20; 95% CI, 0.05-0.35), fat mass index (β coefficient, 0.17; 95% CI, 0.00-0.32), and fasting plasma glucose (β coefficient, 0.22; 95% CI, 0.06-0.37) and lower z scores for HDL cholesterol (β coefficient, -0.19; 95% CI, -0.36 to -0.02). One-SD increments in energy-adjusted UPF consumption were associated with higher z scores for BMI (β coefficient, 0.11; 95% CI, 0.05-0.17), waist circumference (β coefficient, 0.09; 95% CI, 0.02-0.15), fat mass index (β coefficient, 0.11; 95% CI, 0.04-1.18), and fasting plasma glucose (β coefficient, 0.10; 95% CI, 0.03-0.17) and lower HDL cholesterol (β coefficient, -0.07; 95% CI, -0.15 to -0.00). Substituting 100 g of UPFs with 100 g of unprocessed or minimally processed foods was associated with lower z scores of BMI (β coefficient, -0.03; 95% CI, -0.06 to -0.01), fat mass index (β coefficient, -0.03; 95% CI, -0.06 to 0.00), and fasting plasma glucose (β coefficient, -0.04; 95% CI, -0.07 to -0.01).

Conclusions and Relevance

These findings suggest that high UPF consumption in young children is associated with adiposity and other cardiometabolic risk factors, highlighting the need for public health initiatives to promote the replacement of UPFs with unprocessed or minimally processed foods.

Impact of the UK soft drinks industry levy on health and health inequalities in children and adolescents in England: An interrupted time series analysis and population health modelling study

BACKGROUND

The soft drinks industry levy (SDIL) in the United Kingdom has led to a significant reduction in household purchasing of sugar in drinks. In this study, we examined the potential medium- and long-term implications for health and health inequalities among children and adolescents in England.

METHODS AND FINDINGS

We conducted a controlled interrupted time series analysis to measure the effects of the SDIL on the amount of sugar per household per week from soft drinks purchased, 19 months post implementation and by index of multiple deprivation (IMD) quintile in England. We modelled the effect of observed sugar reduction on body mass index (BMI), dental caries, and quality-adjusted life years (QALYs) in children and adolescents (0 to 17 years) by IMD quintile over the first 10 years following announcement (March 2016) and implementation (April 2018) of the SDIL. Using a lifetable model, we simulated the potential long-term impact of these changes on life expectancy for the current birth cohort and, using regression models with results from the IMD-specific lifetable models, we calculated the impact of the SDIL on the slope index of inequality (SII) in life expectancy. The SDIL was found to have reduced sugar from purchased drinks in England by 15 g/household/week (95% confidence interval: -10.3 to -19.7). The model predicts these reductions in sugar will lead to 3,600 (95% uncertainty interval: 946 to 6,330) fewer dental caries and 64,100 (54,400 to 73,400) fewer children and adolescents classified as overweight or obese, in the first 10 years after implementation. The changes in sugar purchasing and predicted impacts on health are largest for children and adolescents in the most deprived areas (Q1: 11,000 QALYs [8,370 to 14,100] and Q2: 7,760 QALYs [5,730 to 9,970]), while children and adolescents in less deprived areas will likely experience much smaller simulated effects (Q3: -1,830 QALYs [-3,260 to -501], Q4: 652 QALYs [-336 to 1,680], Q5: 1,860 QALYs [929 to 2,890]). If the simulated effects of the SDIL are sustained over the life course, it is predicted there will be a small but significant reduction in slope index of inequality: 0.76% (95% uncertainty interval: -0.9 to -0.62) for females and 0.94% (-1.1 to -0.76) for males.

CONCLUSIONS

We predict that the SDIL will lead to medium-term reductions in dental caries and overweight/obesity, and long-term improvements in life expectancy, with the greatest benefits projected for children and adolescents from more deprived areas. This study provides evidence that the SDIL could narrow health inequalities for children and adolescents in England.

Trends in inequalities in childhood overweight and obesity prevalence: a repeat cross-sectional analysis of the Health Survey for England

OBJECTIVE

To examine trends in socio-economic and ethnic inequalities in childhood overweight and obesity in the England between 1995 and 2019 in survey data and to compare these to administrative data.

DESIGN

Observational repeated cross-sectional study using the Health Survey for England (HSE) and National Child Measurement Programme (NCMP).

OUTCOME

Age and sex standardised overweight, obesity and overweight including obesity.

ANALYSIS

Inequalities assessed by parental education, family structure, ethnicity (binary non-white vs white) and area-level Index of Multiple Deprivation. Estimates stratified by age and sex. Trends compared against NCMP data (age 4-5 and 10-11 years).

RESULTS

Prevalence of childhood overweight including obesity increased from 26.0% in 1995 to 31.7% in 2019, with the highest and fastest growing levels in those aged 11-15 years, rising from 29.7% to 38.0%. Despite a plateau in overall childhood obesity since 2004, differences between groups demonstrated widening inequalities over time. Inequalities widened by area-level deprivation, household educational attainment, household structure and ethnicity driven primarily by increased prevalence among socioeconomically disadvantaged children. For example, the gap between children from households with no qualifications versus degree-level qualifications increased from -1.1% to 13.2%, and the gap between single-parent households and couple households increased from 0.5% to 5.3%. HSE trends in prevalence of childhood overweight and obesity by deprivation quintile were consistent with those in NCMP.

CONCLUSION

Overall levels of child overweight and obesity increased between 1995 and 2004. Since then, increases in prevalence among less advantaged groups have driven widening of inequalities.

Overadjustment bias in systematic reviews and meta-analyses of socio-economic inequalities in health: a meta-research scoping review

BACKGROUND

Overadjustment bias occurs when researchers adjust for an explanatory variable on the causal pathway from exposure to outcome, which leads to biased estimates of the causal effect of the exposure. This meta-research review aimed to examine how previous systematic reviews and meta-analyses of socio-economic inequalities in health have managed overadjustment bias.

METHODS

We searched Medline and Embase until 16 April 2021 for systematic reviews and meta-analyses of observational studies on associations between individual-level socio-economic position and health outcomes in any population. A set of criteria were developed to examine methodological approaches to overadjustment bias adopted by included reviews (rated Yes/No/Somewhat/Unclear).

RESULTS

Eighty-four reviews were eligible (47 systematic reviews, 37 meta-analyses). Regarding approaches to overadjustment, whereas 73% of the 84 reviews were rated as Yes for clearly defining exposures and outcomes, all other approaches were rated as Yes for <55% of reviews; for instance, 5% clearly defined confounders and mediators, 2% constructed causal diagrams and 35% reported adjusted variables for included studies. Whereas only 2% included overadjustment in risk of bias assessment, 54% included confounding. Of the 37 meta-analyses, 16% conducted sensitivity analyses related to overadjustment.

CONCLUSIONS

Our findings suggest that overadjustment bias has received insufficient consideration in systematic reviews and meta-analyses of socio-economic inequalities in health. This is a critical issue given that overadjustment bias is likely to result in biased estimates of health inequalities and accurate estimates are needed to inform public health interventions. There is a need to highlight overadjustment bias in review guidelines.

What Are the Challenges of School Nurses in South Korea in Managing Obese Children From Low-Income Households?

Given that the obesity rate among school-age children is increasing, school nurses can play a vital role in managing obesity and encouraging healthy living in school settings. Obese children from low-income backgrounds are more vulnerable than other students and require more careful attention and intervention. This qualitative study aimed to explore and understand the barriers recognized by school nurses in managing obesity in low-income household children. A focus group interview was conducted with 17 school nurses working at an elementary school. Children, home, school, political and structural, and social areas were revealed as intricate factors in obesity management. This study can help understand school nurses' obstacles in managing obese children from low-income families and can help them prepare practical measures to overcome these obstacles.

Education is power: preserving cognition in the UK biobank

Introduction

Dementia is a debilitating syndrome characterized by the gradual loss of memory and cognitive function. Although there are currently limited, largely symptomatic treatments for the diseases that can lead to dementia, its onset may be prevented by identifying and modifying relevant life style risk factors. Commonly described modifiable risk factors include diet, physical inactivity, and educational attainment. Importantly, however, to maximize the utility of our understanding of these risk factors, tangible and meaningful changes to policy must also be addressed.

Objectives

Here, we aim to identify the mechanism(s) by which educational attainment influences cognition.

Methods

We investigated data from 502,357 individuals (Mage = 56.53, SDage = 8.09, 54.40% female) from the UK Biobank cohort via Structural Equation Modelling to illustrate links between predictor variables (i.e., Townsend Deprivation Index, coastal distance, greenspace, years of education), covariates (i.e., participant age) and cognitive function as outcome variables (i.e., pairs-matching, trail-making task B, fluid intelligence).

Results

Our model demonstrated that higher education was associated with better cognitive performance (ps < 0.001), and this relationship was mediated by indices of deprivation, and coastal distance.

Conclusion

Accordingly, our model evinces the mediating effect of socioeconomic and environmental factors on the relationship between years of education and cognitive function. These results further demonstrate the utility and necessity of adapting public policy to encourage equitable access to education and other supports in deprived areas.

Modelled Distributional Cost-Effectiveness Analysis of Childhood Obesity Interventions: A Demonstration

OBJECTIVE

To demonstrate how distributional cost-effectiveness analyses of childhood obesity interventions could be conducted and presented for decision makers.

METHODS

We conducted modelled distributional cost-effectiveness analyses of three obesity interventions in children: an infant sleep intervention (POI-Sleep), a combined infant sleep, food, activity and breastfeeding intervention (POI-Combo) and a clinician-led treatment for primary school-aged children with overweight and obesity (High Five for Kids). For each intervention, costs and socioeconomic position (SEP)-specific effect sizes were applied to an Australian child cohort (n = 4898). Using a purpose-built microsimulation model we simulated SEP-specific body mass index (BMI) trajectories, healthcare costs and quality-adjusted life years (QALYs) from age 4 to 17 years for control and intervention cohorts. We examined the distribution of each health outcome across SEP and determined the net health benefit and equity impact accounting for opportunity costs and uncertainty due to individual-level heterogeneity. Finally, we conducted scenario analyses to test the effect of assumptions about health system marginal productivity, the distribution of opportunity costs and SEP-specific effect sizes. The results of the primary analyses, uncertainty analyses and scenario analyses were presented on an efficiency-equity impact plane.

RESULTS

Accounting for uncertainty, POI-Sleep and High Five for Kids were found to be 'win-win' interventions, with a 67% and 100% probability, respectively, of generating a net health benefit and positive equity impact compared with control. POI-Combo was found to be a 'lose-lose' intervention, with a 91% probability of producing a net health loss and a negative equity impact compared with control. Scenario analyses indicated that SEP-specific effect sizes were highly influential on equity impact estimates for POI-Combo and High Five for Kids, while health system marginal productivity and opportunity cost distribution assumptions primarily influenced the net health benefit and equity impact of POI-Combo.

CONCLUSIONS

These analyses demonstrated that distributional cost-effectiveness analyses using a fit-for-purpose model are appropriate for differentiating and communicating the efficiency and equity impacts of childhood obesity interventions.

Growing Up Unequal: Disparities of Childhood Overweight and Obesity in Indonesia's 514 Districts

BACKGROUND

Childhood obesity is a major public health concern as it increases the risk of premature death and adult disability. Globally, the latest estimates showed that more than 340 million children and adolescents between the ages of 5 and 19 were overweight or obese in 2016. This study aimed to investigate the disparities in childhood overweight and obesity across 514 districts in Indonesia, based on geographic and socioeconomic factors.

METHODS

Geospatial and quantitative analyses were performed using the latest Indonesian Basic Health Survey data from 2018. Dependent variables were rates of overweight and obesity among children aged 5-17 years including by gender.

RESULTS

This study found that the rates of overweight were 17.2%, 17.6%, and 16.8% among all children, boys, and girls, while the rates of obesity were 7.0%, 7.9%, and 6.1%, respectively. Boys were 1.30 times more likely to be obese than girls, while overweight was similar between both sexes. Urban cities had significantly higher prevalence of childhood overweight and obesity compared with rural districts by up to 1.26 and 1.32 times, respectively. In addition, the most developed region had significantly higher prevalence of childhood overweight and obesity than the least developed region by up to 1.37 and 1.38 times, respectively. With regard to socioeconomic factors, our analysis demonstrated a notable disparity in the prevalence of childhood overweight and obesity across income quintiles. Specifically, the wealthiest districts exhibited a 1.18 times higher prevalence of overweight and obesity among all children compared with the poorest districts. This association was particularly pronounced among boys; in the richest quintile, the prevalence of overweight and obesity was 1.24 and 1.26 times higher, respectively, in comparison to the poorest income quintile. In contrast, district-level education appears to exhibit an inverse relationship with the prevalence of childhood overweight and obesity, although the findings were not statistically significant.

A qualitative study about how families coped with managing their well-being, children's physical activity and education during the COVID-19 school closures in England

In 2020, schools in England closed for six months due to COVID-19, resulting in children being home-schooled. There is limited understanding about the impacts of this on children's mental and physical health and their education. Therefore, we explored how families coped with managing these issues during the school closures. We conducted 30 qualitative interviews with parents of children aged 18 years and under (who would usually be in school) between 16 and 21 April 2020. We identified three themes and eight sub-themes that impacted how families coped whilst schools were closed. We found that family dynamics, circumstances, and resources (Theme 1), changes in entertainment activities and physical movement (Theme 2) and worries about the COVID-19 pandemic (Theme 3) impacted how well families were able to cope. A key barrier to coping was struggles with home-schooling (e.g., lack of resources and support from the school). However, parents being more involved in their children's personal development and education were considered a benefit to home-schooling. Managing the lack of entertainment activities and in-person interactions, and additional health worries about loved ones catching COVID-19 were challenges for families. Parents reported adverse behaviour changes in their children, although overall, they reported they were coping well. However, pre-existing social and educational inequalities are at risk of exacerbation. Families with more resources (e.g., parental supervision, access to green space, technology to facilitate home-schooling and no special educational needs) were better able to cope when schools were closed. On balance, however, families appeared to be able to adapt to the schools being closed. We suggest that policy should focus on supporting families to mitigate the widening health and educational gap between families with more and less resources.

Interventions in the first 1000 days to prevent childhood obesity: a systematic review and quantitative content analysis

BACKGROUND

Childhood obesity poses a global health challenge. In recent years, there has been an increase in interventions that begin in pregnancy, putting the concept of early programming and early risk factors into practice. The present study aims to update the findings regarding interventions in the first 1000 days of life.

METHODS

A systematic review based on the PRISMA guidelines was carried out in PubMed, WoS, Scopus and CINAHL to obtain the articles to be analysed. We included those studies published between 2016 and 2021. Human interventions that started within the first 1000 days of life and acted on at least one programming factor were included. Once selected, coding and quantitative content analysis was carried out to obtain a profile of the interventions during the first 1000 days.

RESULTS

From all screened articles, 51 unique interventions, which met the selection criteria, were included. The majority of interventions (81%) took place in high-income areas. Almost all (86%) were targeted at the general population. The majority (54%) started in the second trimester of pregnancy. A clear majority (61%) ended at the time of birth. 44% of the interventions included all pregnant women. Only 48% of these interventions were focused on improving the nutritional status of the offspring in the short term. Most interventions collected the baby's weight at birth (68%).

CONCLUSIONS

It can be concluded that current interventions are not covering as many aspects as they should. Future research should be conducted more frequently in developing countries and target disadvantaged groups. These interventions should include all pregnant women, regardless of their nutritional status, aiming to cover as many programming factors as possible and extending through the first 1000 days of life, with body mass index or skinfolds as measures of effectiveness during this period.

Epidemiology of Obesity

Obesity is in theory defined on the basis of the excess health risk caused by adiposity exceeding the size normally found in the population, but for practical reasons, the World Health Organization (WHO) has defined obesity as a body mass index (weight (kg)/height (m)²) of 30 or above for adults. WHO considers the steep increases in prevalence of obesity in all age groups, especially since the 1970s as a global obesity epidemic. Today, approximately 650 million adult people and approximately 340 million children and adolescence (5-19 years) suffer from obesity. It is generally more prevalent among women and older age groups than among men and younger age groups. Beyond the necessity of availability of food, evidence about causes of obesity is still very limited. However, studies have shown that obesity 'runs in families', where both genetics and environmental, and especially social, factors play important roles. Obesity is associated with an increased risk of many adverse medical, mental and social consequences, including a strong relation to type 2 diabetes. Type 2 diabetes and related metabolic syndrome and diseases are major contributors to the excess morbidity and mortality associated with obesity.

Family socioeconomic status and childhood adiposity in Europe - A scoping review

Childhood obesity is a considerable public health problem worldwide. In Europe, lower parental socioeconomic status (SES) relates to higher childhood adiposity. This scoping review strives to discover, which SES indicators are the most commonly used and meaningful determinants of childhood adiposity (greater level of continuous adiposity indicator, e.g. body mass index z-score, or overweight or obesity categorized by established definitions). The review focused on studies about European general populations from the 21st century (January 2000-April 2021) considering children and adolescents aged 0-17 years. PubMed and reference lists of articles were searched in February-April 2021. Total of 53 studies with 121 association analyses between different SES indicators and adiposity indicators, were identified and reviewed. Different SES indicators were grouped to 25 indicators and further to six indicator groups. The most used indicator was mother's education (n of association analyses = 24) and the most used indicator group was parental education (n of association analyses = 51). Of all association analyses, 55% were inverse, 36% were non-significant, and 8% were positive. Composite SES (80%), parental education (69%) and parental occupation (64%) indicators showed most frequently inverse associations with obesity measures (i.e. lower parental SES associating with higher adiposity), while parental income (50% inverse; 50% non-significant) and property and affluence (42% inverse; 50% nonsignificant) indicators showed approximately even number of inverse and non-significant associations. Instead, majority of parental employment (60%) indicators, showed non-significant associations and 33% showed positive associations (i.e. higher parental SES associating with higher adiposity). Despite some variation in percentages, majority of the associations were inverse in each age group and with different outcome categorizations. In girls and in boys, non-significant associations predominated. It seems that children with parents of higher SES have lower likelihood of adiposity in Europe. Parents' employment appears to differ from other SES indicators, so that having an employed parent(s) does not associate with lower likelihood of adiposity. Positive associations seem to occur more frequently in poorer countries. Criteria for uniform childhood SES and adiposity measures should be established and used in studies in order to be able to produce comparable results across countries.

Economic and social deprivation predicts impulsive choice in children

Impulsivity is an individual difference in decision-making that is a risk factor for a number of health concerns including addiction and obesity. Although impulsivity has a large heritable component, the health concerns associated with impulsivity are not uniformly distributed across society. For example, people from poorer backgrounds are more likely to be overweight, and be dependent on tobacco or alcohol. This suggests that the environmental component of impulsivity might be related to economic circumstances and the availability of resources. This paper provides evidence that children aged 4 to 12 from the most deprived areas in England show greater impulsivity in the form of delay discounting than do children from the least deprived areas. The data are discussed with reference to scarcity-based models of decision-making and to public health inequalities.

Health Economic Aspects of Childhood Excess Weight: A Structured Review

An economic perspective is crucial to understand the broad consequences of childhood excess weight (CEW). These can manifest in the form of elevated health care and societal costs, impaired health status, or inefficiencies in the allocation of resources targeted at its prevention, management, or treatment. Although existing systematic reviews provide summaries of distinct economic research strands covering CEW, they have a restricted focus that overlooks relevant evidence. The overarching aim of this structured review was to update and enhance recent key reviews of four strands of economic evidence in this area, namely, (1) economic costs associated with CEW, (2) health utilities associated with CEW, (3) economic evaluations of interventions targeting CEW, and (4) economic determinants and broader consequences of CEW. Our de novo searches identified six additional studies for the first research strand, five studies for the second, thirty-one for the third, and two for the fourth. Most studies were conducted in a small number of high-income countries. Our review highlights knowledge gaps across all the research strands. Evidence from this structured review can act as data input into future economic evaluations in this area and highlights areas where future economic research should be targeted.

Is it possible to model the impact of calorie-reduction interventions on childhood obesity at a population level and across the range of deprivation: Evidence from the Avon Longitudinal Study of Parents and Children (ALSPAC)

Background

Simulated interventions using observational data have the potential to inform policy and public health interventions where randomised controlled trials are not feasible. National childhood obesity policy is one such area. Overweight and obesity are primarily caused by energy-rich and low-nutrient diets that contribute to a positive net energy imbalance. Using data from the Avon Longitudinal Study of Parents and Children (ALSPAC), we investigated whether causal modelling techniques could be applied to simulate the potential impact of policy-relevant calorie-reduction interventions on population prevalence and inequalities in obesity in childhood.

Methods

Predicted probabilities of obesity at age 11 (UK90 cut offs) were estimated from logistic marginal structural models (MSM) accounting for observed calorie consumption at age 7 and confounding, overall and by maternal occupational social class. A series of population intervention scenarios were modelled to simulate daily calorie-reduction interventions that differed in effectiveness, targeting mechanism and programme uptake level.

Results

The estimated effect of maternal social class on obesity after accounting for confounding and observed calorie intake was provided by the controlled direct effect (CDE), in which, 18.3% of children were living with obesity at age 11 years,. A universal simulation to lower median intake to the estimated average requirement (EAR) (a 6.1% reduction in daily calories) with 75% uptake reduced overall obesity prevalence by 0.6%; there was little impact on inequalities. A targeted intervention to limit consumption to the EAR for children with above average intake reduced population obesity prevalence at 11 years by 1.5% but inequalities remained broadly unchanged. A targeted intervention for children of low-income families reduced prevalence by 0.7% and was found to slightly reduce inequalities.

Conclusions

MSMs allow estimation of effects of simulated calorie-reduction interventions on childhood obesity prevalence and inequalities, although estimates are limited by the accuracy of reported calorie intake. Further work is needed to understand causal pathways and opportunities for intervention. Nevertheless, simulated intervention techniques have promise for informing national policy where experimental data are not available.

Parental feeding and childhood genetic risk for obesity: exploring hypothetical interventions with causal inference methods

BACKGROUND

Parental-feeding behaviors are common intervention targets for childhood obesity, but often only deliver small changes. Childhood BMI is partly driven by genetic effects, and the extent to which parental-feeding interventions can mediate child genetic liability is not known. Here we aim to examine how potential interventions on parental-feeding behaviors can mitigate some of the association between child genetic liability and BMI in early adolescence, using causal inference methods.

METHODS

Data from the Avon Longitudinal Study of Parents and Children were used to estimate an interventional disparity measure for a child polygenic score for BMI (PGS-BMI) on BMI at 12 years. The approach compares counterfactual outcomes for different hypothetical interventions on parental-feeding styles applied when children are 10-11 years (n = 4248). Results are presented as adjusted total association (Adj-Ta) between genetic liability (PGS-BMI) and BMI at 12 years, versus the interventional disparity measure-direct effect (IDM-DE), which represents the association that would remain, had we intervened on parental-feeding under different scenarios.

RESULTS

For children in the top quintile of genetic liability, an intervention shifting parental feeding to the levels of children with lowest genetic risk, resulted in a difference of 0.81 kg/m² in BMI at 12 years (Adj-Ta = 3.27, 95% CI: 3.04, 3.49; versus IDM-DE = 2.46, 95% CI: 2.24, 2.67).

CONCLUSIONS

Findings suggest that parental-feeding interventions have the potential to buffer some of the genetic liability for childhood obesity. Further, we highlight a novel way to analyze potential interventions for health conditions only using secondary data analyses, by combining methodology from statistical genetics and social epidemiology.

Modeling the impact of calorie-reduction interventions on population prevalence and inequalities in childhood obesity in the Southampton Women's Survey

BACKGROUND

In the United Kingdom, rates of childhood obesity are high and inequalities in obesity have widened in recent years. Children with obesity face heightened risks of living with obesity as adults and suffering from associated morbidities. Addressing population prevalence and inequalities in childhood obesity is a key priority for public health policymakers in the United Kingdom and elsewhere. Where randomized controlled trials are not possible, potential policy actions can be simulated using causal modeling techniques.

OBJECTIVES

Using data from the Southampton Women's Survey (SWS), a cohort with high quality dietary and lifestyle data, the potential impact of policy-relevant calorie-reduction interventions on population prevalence and inequalities of childhood obesity was investigated.

METHODS

Predicted probabilities of obesity (using UK90 cut-offs) at age 6-7 years were estimated from logistic marginal structural models adjusting for observed calorie consumption at age 3 years (using food diaries) and confounding. A series of policy-relevant intervention scenarios were modeled to simulate reductions in energy intake (differing in effectiveness, the targeting mechanisms, and level of uptake).

RESULTS

At age 6-7 years, 8.3% of children were living with obesity, after accounting for observed energy intake and confounding. A universal intervention to lower median energy intake to the estimated average requirement (a 13% decrease), with an uptake of 75%, reduced obesity prevalence by 1% but relative and absolute inequalities remained broadly unchanged.

CONCLUSIONS

Simulated interventions substantially reduced population prevalence of obesity, which may be useful in informing policymakers.

Area-level and family-level socioeconomic position and body composition trajectories: longitudinal analysis of the UK Millennium Cohort Study

BACKGROUND

Inequalities in the trajectories of body composition in childhood and adolescence have been infrequently studied. Despite the importance of environmental factors in obesity development, little research has looked at area-level socioeconomic position, independent of family socioeconomic position. We aimed to assess how inequalities in body composition develop with age.

METHODS

The Millennium Cohort Study is a longitudinal study of 19 243 families who had a child born between 2000 and 2002 in the UK. Multilevel growth curve models were applied to examine change in fat mass index (FMI), fat free mass index (FFMI; using the Benn index), and fat mass to fat free mass ratio (FM:FFM), measured using Bioelectrical Impedance Analysis, from ages 7 years to 17 years by the Index of Multiple Deprivation (IMD) and household income at baseline.

FINDINGS

Inequalities in FMI and FM:FFM ratio are evident at age 7 years and widen with age. At age 17 years, adolescents in the most disadvantaged IMD group had FMI 0·57 kg/mB (B=Benn parameter; 95% CI 0·43 to 0·70) higher and FM:FFM ratio 0·037 (95% CI 0·026 to 0·047) higher compared with the most advantaged group. Disadvantaged socioeconomic position is associated with higher FFMI but is reversed in adolescence after adjustment for FMI. Inequalities were greater in girls at age 7 years (mean FMI 0·22 kg/mB; 95% CI 0·13 to 0·32) compared with boys of the same age (0·05 kg/mB; -0·04 to 0·15, p=0·3), but widen fastest in boys, especially for FMI, in which there was over an 11 times increase in the inequality from age 7 years of 0·05kg/mB (95% CI -0·04 to 0·15) to 0·62 kg/mB at 17 years (0·42 to 0·82). Inequalities for the IMD were similar to income, and persisted at age 17 years independent of family socioeconomic position.

INTERPRETATION

Childhood and adolescence is an important period to address inequalities in body composition, as they emerge and widen. Policies should consider FFM as well as FM, and inequalities in the environment.

FUNDING

Medical Research Council, Economic and Social Research Council.

Socioeconomic inequalities in the prevalence of overweight and obesity among Portuguese preschool-aged children: Changes from 2009 to 2016

OBJECTIVES

We evaluated, for the first time in Portugal, the prevalence of overweight and obesity according to parental education in a population of preschool-aged Portuguese children in 2009/2010 and 2016/2017.

METHODS

Anthropometric data were collected in public and private preschools (n = 1996 in 2009/2010; n = 2077 in 2016/2017). Body mass index was calculated and weight status categories were based on the International Obesity Task Force cutoff points. Parental education level was self-reported.

RESULTS

Prevalence of overweight (17.1%-14.1%; p < 0.001) and obesity (6.6%-3.9%, p < 0.001) was lower in 2016/2017 than in 2009/2010, with higher rates being found in the north of the country. Parental education was significantly associated with childhood overweight and obesity and inequalities between low- and high-education increased between the two periods.

CONCLUSIONS

While a decrease in childhood overweight and obesity were positive findings, the prevalence is still high and shows pronounced socioeconomic differences. Policies for obesity prevention need to be inclusive and tackle inequalities, with interventions tailored to suit local contexts.

Effectiveness of lifestyle interventions in preventing harmful weight gain among adolescents: A systematic review of systematic reviews

Obesity in adolescence is associated with stigma during school years, early emergence of co-morbidities in adulthood and premature mortality. Adolescence presents a key window of opportunity to intervene for building healthy eating and physical activity routines and prevent weight gain. This review of reviews assesses the evidence on the effectiveness of prevention interventions conducted with adolescents. Nine reviews assessing the effects of lifestyle interventions in adolescents (defined as age 10 to 19 years old) on weight gain were identified from the 10 health databases searched. Only four reviews conducted meta-analyses, of which, three (two exercise-focused) demonstrated positive changes in primary outcomes of body mass index (BMI) and/or BMI z-score (range of decrease in BMI from 0.06 to 0.47 kg/m²⁾ ). Most were conducted in school settings, and all but two reviews were of low quality. Few reviews reported external validity components that would enable clearer directions for policy makers to implement in real-world settings. More than 140 distinct interventions were included in the reviews, but there remains a serious gap in evidence for effective interventions in adolescents.

Social Ecological Barriers for Healthy Eating of Obese Children and Their Caregivers in Low-income Families in South Korea

In this qualitative study, the focus is on healthy eating in children from low-income families who visit a Community Child Care center (CCC) in South Korea. Barriers for healthy eating were identified using focus group interviews with low-income overweight and obese children and their caregivers and applying a social ecological model as well as the framework analysis for qualitative data. The need for theory- and evidence-based health promotion interventions is indicated, at the level of the family, but also at the level of collaboration among all stakeholders, as well as multi-level policy changes.

Socioeconomic Status and Childhood Obesity: a Review of Literature from the Past Decade to Inform Intervention Research

PURPOSE OF REVIEW

This is a review of the patterns, conceptualization, and suggested mechanisms underlying the relationship of socioeconomic status (SES) to obesity in childhood and the implications of these data for interventions going forward.

RECENT FINDINGS

Adiposity and SES are negatively associated in high-income countries and positively associated in medium to low-income countries. Several mechanisms, such as early introduction of solid food and parental behaviors, which may explain the association of SES and adiposity, have been identified. Parental education and adiposity and early pediatric nutrition appear to be particularly salient SES-related effectors on adiposity. There is a clear association of SES and adiposity which is affected by population affluence. Evaluation of the relationship of SES and obesity in children are complicated by the complexity of SES and lack of common definition. A number of SES-related interventional targets have been identified. Intervention research should ensure they are addressing SES-associated issues in the study population.

Change in modifiable maternal characteristics and behaviours between consecutive pregnancies and offspring adiposity: A systematic review

Causal evidence links modifiable maternal exposures during the periconceptional period with offspring obesity. The interconception period may be an important time to intervene. We systematically identified studies examining change in modifiable maternal exposures between pregnancies and offspring adiposity. We searched for longitudinal studies published between 1990 and 2019, which included measurements taken on at least two occasions in the period from 1 year prior to the conception of the first birth to the time of the second birth, and which included a measure of adiposity in second, or higher order, siblings. Age, ethnicity and genetics were not considered modifiable; all other factors including length of the interpregnancy interval were. Eleven studies satisfied the inclusion criteria. Higher interpregnancy weight gain or loss, maternal smoking inception, mothers smoking in their first pregnancy and quitting, increasing the number of cigarettes smoked and longer interpregnancy intervals were positively associated with adiposity in second or higher order children. Vaginal birth after caesarean delivery was protective. Further research is needed to ascertain whether the risk of adiposity is fixed based on first pregnancy exposures or if interpregnancy change alters the risk for a subsequent child. This can inform the type and effectiveness of interventions for mothers prior to a subsequent pregnancy.

Assessing childhood health outcome inequalities with area-based socioeconomic measures: a retrospective cross-sectional study using Manitoba population data

BACKGROUND

Socioeconomic gradients in health exist in Canada. Although multiple Canadian area-based socioeconomic measures (ABSM) have been developed, none have been specifically validated against pediatric outcomes. Our objective was to compare the strength of association between key pediatric health outcomes and a number of ABSM, including income quintile.

METHODS

This was a retrospective cross-sectional assessment of the association between socioeconomic status (SES) measured by ABSM and 20 specific pediatric health outcomes. Data from the Manitoba Population Research Data Repository were used for residents aged 0-19 years from 2010 to 2015. Outcomes included birth-related events (e.g. mortality), vaccination uptake, hospitalizations, and teen pregnancy. Regression goodness of fit was used to assess the strength of individual associations. Inequality was measured by slope index of inequality (SII) and relative index of inequality (RII).

RESULTS

Overall, 19 of 20 outcomes had socioeconomic gradients identified by SII and RII. The multidimensional CAN-Marg indices had the best explanatory power in standard regression models. The simplest ABSM-income quintile-detected 16 of 19 confirmed inequalities, more than any other single measure.

CONCLUSIONS

At all ages, many pediatric health outcomes in Manitoba were associated with significant socioeconomic inequalities; while income quintile detected most, CAN-Marg composite indices had the best explanatory power.

Income, Race and its Association with Obesogenic Behaviors of U.S. Children and Adolescents, NHANES 2003-2006

OBJECTIVES

To describe the associations of income and race with obesogenic behaviors and % body fat among a large sample of U.S. children and adolescents.

DESIGN

Data were obtained from the 2003-2004 and 2005-2006 National Health and Nutritional Examination Survey. Multiple linear regression models and interactions were used to examine the associations of moderate-to-vigorous physical activity (MVPA), sedentary time, diet quality, and screen-time with income-to-poverty ratio and race. Separate stratified analyses explored associations among individual obesogenic behaviors within race and income groups.

RESULTS

This study included children and adolescents (n = 3551, mean = 13.1 years, SD = 3.9 years) who were 37% Hispanic, 27% White, and 35% Black. Overall, Hispanic children/adolescents had significantly higher levels of adiposity (3.6, 95 CI = 0.9, 6.3) than white children and adolescents. Medium-income children and adolescents engaged in less MVPA (- 3.3 min, 95 CI = - 5.1, - 1.5), had poorer diet quality (- 1.1, 95 CI = - 1.9, - 0.2), and used screens less (- 33.9 min, 95 CI = - 45.4, - 22.4) than children and adolescents from low-income households. High-income children and adolescents also engaged in less MVPA (- 3.1 min, 95 CI = - 5.5, - 0.7) and used screens less (- 62.9 min, 95 CI = - 78.3, - 47.4) than children and adolescents from low-income households. However, there were significant race/ethnicity-by-income interactions for high-income Hispanic children and adolescents with diet quality (- 3.5 HEI-2010 score, 95 CI = - 6.6, - 0.4) and screen time (66.9 min, 95 CI = 24.7, 109.0). There was also a significant race/ethnicity-by-income interaction for the screen-time of Black children and adolescents from medium (33.8 min, 95% CI 0.2, 67.3) and high (75.8 min, 95% CI 34.7, 117.0) income households.

CONCLUSIONS

There appears to be a complex relationship that varies by race/ethnicity between income, obesogenic behaviors, and adiposity levels among children and adolescents. More work is needed to identify the behavioral mechanisms that are driving disparate rates of overweight and obesity among minority children and those from low-income households.

Impact of family income on the lifestyle and physique of schoolchildren in Higashi-Osaka City, Japan

BACKGROUND

There is limited evidence about the ways in which poverty affects the health and educational environment of schoolchildren. We investigated the impact of family income on the lifestyle and physique of children in Japan.

METHODS

We mailed a questionnaire to 1,000 fifth-grade elementary school and 1,000 second-grade junior high school students and their parents in Higashi-Osaka City from August to September, 2017. Physique was evaluated based on standard body weight for height.

RESULTS

The questionnaire survey recovery rate was 31.3%. Overweight / obesity was confirmed in 8.1% of males and 3.7% of females. The prevalence of overweight / obesity was higher in children of families with incomes under the median than in families with incomes over the median only in females. The number of children with less than 1 h of studying time after school was significantly higher in children of families with incomes under the median, as well as in overweight / obese children. In children of families with incomes under the median, the rates of possessing books, exercise equipment, and their own room were lower than in children of families with incomes over the median, but there was no difference in the rates of possessing smartphones, or video games, based on income.

CONCLUSIONS

Children of low-income families have an educational handicap, which is one of the risk factors for the "chain of poverty."

Socio-economic and cultural disparities in diet among adolescents and young adults: a systematic review

OBJECTIVE

To explore dietary differences according to socio-economic and sociocultural characteristics of adolescents and young adults.

DESIGN

A systematic review was conducted.

SETTING

The main search source was MEDLINE, consulted between January 2012 and March 2017. Quality of selected studies was assessed based on dietary measurement method, sample selection, socio-economic indicator choice and statistical modelling.

PARTICIPANTS

Cross-sectional and longitudinal studies, assessing relationships between socio-economic status and dietary intake (patterns, scores and food groups) in the 10- to 40-year-old general population of high-income countries, were selected.

RESULTS

Among the 7250 reports identified, forty were selected, seventeen of which were of high quality; their conclusions, related only to adolescents, were combined and presented. The most favourable dietary patterns, higher dietary scores, greater consumption of fruits, vegetables and dairy products, and lower consumption of sugary sweetened beverages and energy-dense foods, were associated with better parental socio-economic status, particularly in terms of higher education. Migrant status was associated with plant-based patterns, greater consumption of fruits and vegetables and of sugary sweetened beverages and energy-dense foods. For the other food groups, and for young adults, very few high-quality studies were found.

CONCLUSIONS

The socio-economic gradient in adolescent diets requires confirmation by higher-grade studies of a wider set of food groups and must be extended to young adult populations. Future nutritional interventions should involve the most vulnerable adolescent populations, taking account of socio-economic status and migration.

Maternal and early-life area-level characteristics and childhood adiposity: A systematic review

There is a cross-sectional evidence that physical and social environments are linked to childhood adiposity. Evidence is scarce for the role of preconception, pregnancy, and early-life area-level characteristics in shaping childhood adiposity. We aimed to systematically review evidence for associations between physical and social environmental conditions experienced in these periods and childhood adiposity. Published literature was identified from the CINAHL, Embase, MEDLINE, and PsycINFO databases. Longitudinal studies linking an area-level environmental exposure in the preconception, pregnancy, or early-life (less than 1 year) periods and a measure of adiposity between the ages of 2 and 12 years were examined. Eight studies in the United States, Denmark, South Korea, United Kingdom, and Canada satisfied the inclusion criteria. Storm-induced maternal stress, nitrogen oxides exposure, traffic noise, and proximity were associated with greater childhood adiposity. Frequent neighbourhood disturbances were associated with lower adiposity, while particulate matter exposure was associated with both higher and lower adiposity in childhood. Area-level characteristics may play a role in the ongoing obesity epidemic. There is a limited evidence of longitudinal associations between preconception, pregnancy, and early-life area-level characteristics with childhood adiposity. Numerous factors that appear important in cross-sectional research have yet to be assessed longitudinally, both individually and in combination.

The association between body mass index, primary healthcare use and morbidity in early childhood: findings from the Born In Bradford cohort study

OBJECTIVES

The objective of the article was to examine the association between body mass index (BMI), health and general practice (GP) healthcare use in early childhood.

STUDY DESIGN

This study is a prospective cohort study.

METHODS

Multivariate Poisson and logistic regression models were used to explore the association between BMI and health outcomes using data from the Born In Bradford cohort study, linked to routine data capturing objective measures of BMI at age 5 years, alongside GP appointment rates, GP prescriptions and specific morbidities in the subsequent 3-year period.

RESULTS

Compared with healthy weight, children who were obese at the age of 5 years had significantly higher rates of GP appointments (incident rate ratio 1.14, 95% confidence interval [CI]: 1.06-1.23), GP prescriptions (incident rate ratio 1.15, 95% CI: 1.04-1.27), asthma (odds ratio 1.46, 95% CI: 1.21-1.77), sleep apnoea (odds ratio 2.50, 95% CI: 1.36-4.58), infections (incident rate ratio 1.19, 95% CI: 1.08-1.30), antibiotic prescriptions (incident rate ratio 1.25, 95% CI: 1.10-1.42) and accidents (incident rate ratio 1.20, 95% CI: 1.01-1.42) in the subsequent 3 years. Underweight children were found to have higher rates of GP appointments (incident rate ratio 1.25, 95% CI: 1.04-1.52), but there were no differences between overweight and healthy weight children.

CONCLUSIONS

Childhood obesity was found to be associated with increased primary healthcare use and a range of poorer health outcomes at the age of 8 years, underlining the importance of reducing childhood obesity in early childhood.

What if all children achieved WHO recommendations on physical activity? Estimating the impact on socioeconomic inequalities in childhood overweight in the UK Millennium Cohort Study

BACKGROUND

The World Health organization (WHO) recommends that children engage in 60 min daily moderate-to-vigorous physical activity (dMVPA). Just half of children in the UK achieve these levels (with similarly low levels in other high-income countries). Thus, the dMVPA target is a focus of national obesity strategies. However, the potential impact of increased physical activity on prevalence and inequalities in childhood overweight is unknown. Using objective data from the Millennium Cohort Study (∼18 000 children born 2000-02) we simulated a series of hypothetical physical activity intervention scenarios: achievement of the target, and more realistic increases demonstrated in trials.

METHODS

Predicted probabilities of overweight and obesity (using measured heights and weights at age 11) were estimated in multinomial marginal structural models, adjusting for dMVPA (measured with accelerometers at age 7) and confounding. Inequalities were assessed according to household income quintiles [risk ratios (RRs) and risk differences (RDs)]. Intervention scenarios were simulated by re-estimating predicted probabilities of overweight/obesity after manipulating (increasing) dMVPA by varying amounts, for different eligibility criteria and with varying uptake. Analyses included 6493 children with accelerometer data. Survey weights and multiple imputation addressed sampling design, attrition and item missingness.

RESULTS

In all, 27% children were overweight/obese, with relative and absolute inequalities in the expected direction; 51% children were achieving 60 min dMVPA, with those from the lowest income quintile achieving, on average, 3 min more dMVPA than those from the highest income quintile. A simulation of universal achievement of the dMVPA target reduced the prevalence of overweight/obesity to 22%, but increased relative inequalities (absolute inequalities were unchanged). Smaller increases in dMVPA (informed by intervention evidence) did little to reduce prevalence or inequalities, even when targeting high-risk groups.

CONCLUSIONS

Universal achievement of the WHO dMVPA target, if attainable, would reduce prevalence of childhood overweight and obesity but not inequalities. Scale-up of more realistic interventions would have limited impact.

Family and neighborhood socioeconomic inequality in cryptorchidism and hypospadias: A nationwide study from Sweden

OBJECTIVES

To examine whether there is an association between neighborhood deprivation and incidence of cryptorchidism and hypospadias, after accounting for family-level and individual-level sociodemographic characteristics.

METHODS

All boys born in Sweden between January 1, 2001 and December 31, 2010 were followed. Data were analyzed by multilevel logistic regression, with family-level and individual-level characteristics at the first level and level of neighborhood deprivation at the second level.

RESULTS

During the study period, among a total of 497,584 boys, 8,584 (1.7%) and 3,704 (0.7%) were diagnosed with cryptorchidism and hypospadias, respectively. Cumulative rates for cryptorchidism and hypospadias increased with increasing levels of neighborhood deprivation. In the study population, 1.5 per 100 and 2.0 per 100 boys, in the least and most deprived neighborhoods were diagnosed with cryptorchidism and 0.7 per 100 and 0.9 per 100 boys were diagnosed with hypospadias. Incidence of hospitalization for cryptorchidism and hypospadias increased with increasing neighborhood-level deprivation across all family-level and individual-level sociodemographic categories. The odds ratio (OR) for cryptorchidism and hypospadias for those living in high-deprivation neighborhoods versus those living in low-deprivation neighborhoods was 1.13 (95% confidence interval [CI] = 1.05-1.21) and 1.24 (95% CI = 1.12-1.37). High neighborhood deprivation remained significantly associated with higher odds of hypospadias after adjustment for family-level and individual-level sociodemographic characteristics (OR = 1.20, 95% CI = 1.08-1.35).

CONCLUSIONS

This study is the largest so far on neighborhood influences on cryptorchidism and hypospadias. Our results suggest that neighborhood deprivation is associated with a moderate incidence of hypospadias independent of family-level and individual-level sociodemographic characteristics.

Geographic and area-level socioeconomic variation in cardiometabolic risk factor distribution: a systematic review of the literature

INTRODUCTION

A growing number of publications report variation in the distribution of cardiometabolic risk factors (CMRFs) at different geographic scales. A review of these variations may help inform policy and health service organisation.

AIM

To review studies reporting variation in the geographic distribution of CMRFs and its association with various proxy measures of area-level socioeconomic disadvantage (ASED) among the adult ( ≥ 18 years) population across the world.

METHODS

A systematic search for published articles was conducted in four databases (MEDLINE (Ovid), PubMed, Scopus and Web of Science) considering the interdisciplinary nature of the review question. Population-based cross-sectional and cohort studies on geographic variations of one or more biological proxies of CMRFs with/without an analysed contextual association with ASED were included. Two independent reviewers screened the studies and PRISMA guidelines were followed in the study selection and reporting.

RESULT

A total of 265 studies were retrieved and screened, resulting in 24 eligible studies. The review revealed reports of variation in the distribution of CMRFs, at varying geographic scales, in multiple countries. In addition, consistent associations between ASED and higher prevalence of CMRFs were demonstrated. The reports were mainly from industrialised nations and small area geographic units were frequently used.

CONCLUSION

Geographic variation in cardiometabolic risk exists across multiple spatial scales and is positively associated with ASED. This association is independent of individual-level factors and provides an imperative for area-based approaches to informing policy and health service organisation. The study protocol is registered in International prospective register of systematic reviews (Register No: CRD42018115294) PROSPERO 2018.

A Review of Systematic Reviews Targeting the Prevention and Treatment of Overweight and Obesity in Adolescent Populations

PURPOSE

Adolescent obesity is a powerful predictor of morbidity and mortality, yet amenable to modifiable behaviors. To accurately summarize the effects of behavioral interventions on changes in adolescent body mass index and/or weight status, we assessed existing systematic reviews for reporting transparency and methodological quality.

METHODS

Five databases were searched through September 2017 to identify relevant systematic reviews. Reviews were evaluated for reporting transparency and methodological quality using PRISMA Reporting Checklist and Assessment of Multiple Systematic Reviews Instrument. Evidence was synthesized across high-quality reviews.

RESULTS

Four of twelve systematic reviews were of high methodological quality. All four focused on the treatment of overweight/obesity in adolescent populations, representing 97 international studies. Findings indicate intervention compared with no intervention/wait list showed larger effects for improving BMI/BMI z-scores. Small improvements (averaging a 3.7-kg decrease) in weight/weight percentile were observed following a supervised exercise plus dietary and/or behavior support intervention. Health-related quality of life may improve following interventions, but overall attention to associated psychological variables (depression, self-esteem/perception) is limited.

CONCLUSIONS

Adherence to objective checklists and protocols for rigorous conduct and reporting of systematic reviews is warranted. Consensus evidence is urgently needed to define and report behavior change interventions related to obesity prevention and treatment.

Risk and Protective Factors for Child Overweight/Obesity Among Low Socio-Economic Populations in Israel: A Cross Sectional Study

Background and Aims: Scientific evidence regarding protective factors that contribute to healthy weight in childhood is limited and is particularly scarce in lower socio-economic populations in different ethnic groups. This study aimed to assess the prevalence of biological, behavioral and psychosocial factors for child overweight/obesity in Jewish and Arab population groups in Israel, and to compare their associations with child overweight/obesity in the two groups. Methods: Children aged 5-6 years were randomly selected from 20 Mother and Child Health clinics in towns and villages of lowest socio-economic ranking in Northern Israel. Children and mothers were invited for a special "One Stop Shop-Preparation for School" visit which included growth measurements. Questionnaires were distributed to mothers for self-report on biological, SES, psychological and lifestyle factors. Perinatal and early nutritional data were retrieved from clinic records. Multivariate analyses using logistic regression models predicting child overweight/obesity were conducted separately for Jewish (N = 371) and Arab (N = 575) children. Results: Overweight/obesity (BMI ≥85th centile) rates were higher in Jewish (25%) than Arab (19%) children. In both Jewish and Arab groups, respectively, maternal BMI (OR = 1.10 [95%CI = 1.04, 1.17]; OR = 1.08 [95%CI = 1.04, 1.13]), and child birthweight (OR = 1.33 [95%CI = 1.04, 1.71]; OR = 1.39 [95%CI = 1.11, 1.73]) were significant risk factors for overweight/obesity, and maternal self-efficacy regarding child's lifestyle was significantly protective (OR = 0.49 [95%CI = 0.28, 0.85]; OR = 0.54 [95%CI = 0.34, 0.85]). Additionally, four other maternal psychological and child behaviors were significantly associated with overweight/obesity in the Jewish group and two child lifestyle behavior factors in the Arab group. Moreover, significant interactions indicating moderation effects were found only in the Jewish group: maternal education and maternal age moderated the effect of maternal BMI on child overweight/obesity. No other moderation of risk factors was found. Discussion: In this study of children from low SES families, protective factors contributed to healthy child weight alongside risk factors for overweight/obesity. They differed between the population groups, and fewer variables explained overweight/obesity in Arab children. Although further expansion of these findings is required they point at the relevance of protective factors, maternal self-efficacy in particular, for understanding childhood obesity in specific ethnic contexts and for planning culturally adapted prevention programs in disadvantaged populations.

Regional disparities in obesity/emaciation and income in schoolchildren in Osaka City

BACKGROUND

We assessed the association between socioeconomic status at residential area-level in the 24 wards of Osaka City, differentiated by indices of mean income-related deprivation, and inequalities in childhood obesity and emaciation.

METHODS

Data from representative samples of 26 474 schoolchildren (first and fifth grades of elementary school, and third grade of junior high school [i.e. ninth grade of elementary school]) in Osaka City taken from a somatometric check in spring 2016 were analyzed. The cross-sectional association between socioeconomic factors, that is, the census-based annual income of each ward, and the prevalence of childhood overweight/obesity and emaciation, was examined.

RESULTS

The prevalence of overweight/obesity in boys and girls in the first and fifth grades of elementary school and the third grade of junior high school was 3.98% and 4.53%, 10.18% and 8.69%, and 7.02% and 5.55%, respectively. The prevalence of emaciation in boys and girls in the first and fifth grades of elementary school, and the third grade of junior high school was 0.14% and 0.10%, 0.46% and 1.06% and 3.95% and 3.05%, respectively. Mean physical value, expressed as % degree of overweight, had a negative correlation with mean annual income of each ward in girls in the first and fifth grades of elementary school, girls in the third grade of junior high school and boys in the first grade of elementary school.

CONCLUSIONS

Overweight/obesity at school age is greatly affected by poverty. Efforts should be made to prevent emaciation not only in girls, but also in boys, in junior high school.

Neighborhood deprivation and biomarkers of health in Britain: the mediating role of the physical environment

BACKGROUND

Neighborhood deprivation has been consistently linked to poor individual health outcomes; however, studies exploring the mechanisms involved in this association are scarce. The objective of this study was to investigate whether objective measures of the physical environment mediate the association between neighborhood socioeconomic deprivation and biomarkers of health in Britain.

METHODS

We linked individual-level biomarker data from Understanding Society: The UK Household Longitudinal Survey (2010-2012) to neighborhood-level data from different governmental sources. Our outcome variables were forced expiratory volume in 1 s (FEV1%; n=16,347), systolic blood pressure (SBP; n=16,846), body mass index (BMI; n=19,417), and levels of C-reactive protein (CRP; n=11,825). Our measure of neighborhood socioeconomic deprivation was the Carstairs index, and the neighborhood-level mediators were levels of air pollutants (sulphur dioxide [SO2], particulate matter [PM10], nitrogen dioxide [NO2], and carbon monoxide [CO]), green space, and proximity to waste and industrial facilities. We fitted a multilevel mediation model following a multilevel structural equation framework in MPlus v7.4, adjusting for age, gender, and income.

RESULTS

Residents of poor neighborhoods and those exposed to higher pollution and less green space had worse health outcomes. However, only SO2 exposure significantly and partially mediated the association between neighborhood socioeconomic deprivation and SBP, BMI, and CRP.

CONCLUSION

Reducing air pollution exposure and increasing access to green space may improve population health but may not decrease health inequalities in Britain.

Household income is associated with food and nutrient intake in Japanese schoolchildren, especially on days without school lunch

Objective

The present study aimed to examine the association between household income and the intake of foods and nutrients by Japanese schoolchildren, and any differences between days with and without school lunch.

Design

This was a cross-sectional study. Children, with the support of their parents, kept dietary records with photographs for 4 d (2 d with school lunch and 2 d without). The socio-economic status of each family was obtained from a questionnaire completed by the parents.

Setting

Japan.

Subjects

All students in 5th grade (10–11 years old) at nineteen schools in four prefectures and their parents (1447 pairs of students and parents) were invited to take part in the study; 836 pairs of complete data sets were analysed.

Results

The average results of four days of dietary records showed that lower income level was associated with a lower intake of fish/shellfish, green vegetables and sugar at the food group level, a lower intake of protein and several micronutrients, and a higher energy intake from carbohydrates at the nutrient level among the children. These associations between income and food/nutrient intake were not significant on days with school lunches, but were significant on days without school lunch.

Conclusions

Our study confirmed an association between household income and the amount of foods and nutrients consumed by Japanese schoolchildren, and suggested that school lunches play a role in reducing disparities in the diets of children from households with various incomes.

Association between Childhood Obesity and Neighbourhood Accessibility to Fast-Food Outlets: A Nationwide 6-Year Follow-Up Study of 944,487 Children

OBJECTIVES

The aim of this 6-year follow-up study was to examine whether neighbourhood accessibility to fast-food outlets was associated with diagnosed childhood obesity, after adjustment for neighbourhood- and individual-level socio-demographic factors.

METHODS

This 6-year follow-up study comprised 484,677 boys and 459,810 girls aged 0-14 years in Sweden. The follow-up period ran from January 1, 2005, until hospitalisation/out-patient treatment for obesity, death, emigration or the end of the study period on December 31, 2010. Multilevel logistic regression models (individual-level factors at the first level and neighbourhood-level factors at the second level) were used to calculate odds ratios (ORs) with 95% confidence intervals (95% CIs).

RESULTS

We identified 6,968 obesity cases (3,878 boys and 3,090 girls) during the follow-up period. Higher odds of childhood obesity for those living in neighbourhoods with accessibility to fast-food outlets was observed (OR = 1.14, 95% CI = 1.07-1.22) that remained significant after adjustments (OR = 1.06, 95% CI = 1.00-1.13).

CONCLUSIONS

This prospective nationwide study showed that the neighbourhood accessibility to fast-food outlets was independently associated with increased odds of diagnosed childhood obesity. This finding implicates that residential environments should be considered when developing health promotion programmes.

Neighbourhood Deprivation, Individual-Level and Familial-Level Socio-demographic Factors and Risk of Congenital Heart Disease: A Nationwide Study from Sweden

OBJECTIVES

The purpose of the study is to examine whether there is an association between neighbourhood deprivation and incidence of congenital heart disease (CHD), after accounting for family- and individual-level potential confounders.

METHODS

All children aged 0 to 11 years and living in Sweden (n = 748,951) were followed between January 1, 2000 and December 31, 2010. Data were analysed by multilevel logistic regression, with family- and individual-level characteristics at the first level and level of neighbourhood deprivation at the second level.

RESULTS

During the study period, among a total of 748,951 children, 1499 (0.2%) were hospitalised with CHD. Age-adjusted cumulative hospitalisation rates for CHD increased with increasing level of neighbourhood deprivation. In the study population, 1.8 per 1000 and 2.2 per 1000 children in the least and most deprived neighbourhoods, respectively, were hospitalised with CHD. The incidence of hospitalisation for CHD increased with increasing neighbourhood-level deprivation across all family and individual-level socio-demographic categories. The odds ratio (OR) for hospitalisation for CHD for those living in high-deprivation neighbourhoods versus those living in low-deprivation neighbourhoods was 1.23 (95% confidence interval (CI) = 1.04-1.46). In the full model, which took account for age, paternal and maternal individual-level socio-economic characteristics, comorbidities (e.g. maternal type 2 diabetes, OR = 3.03; maternal hypertension, OR = 2.01), and family history of CHD (OR = 3.27), the odds of CHD were slightly attenuated but did not remain significant in the most deprived neighbourhoods (OR = 1.20, 95% CI = 0.99-1.45, p = 0.057).

CONCLUSIONS

This study is the largest so far on neighbourhood influences on CHD, and the results suggest that deprived neighbourhoods have higher rates of CHD, which represents important clinical knowledge. However, the association does not seem to be independent of individual- and family-level characteristics.

The Migrant Paradox in Children and the Role of Schools in Reducing Health Disparities: A Cross-Sectional Study of Migrant and Native Children in Beijing, China

Migrants usually exhibit similar or better health outcomes than native-born populations despite facing socioeconomic disadvantages and barriers to healthcare use; this is known as the “migrant paradox.” The migrant paradox among children is highly complex. This study explores whether the migrant paradox exists in the health of internal migrant children in China and the role of schools in reducing children’s health disparities, using a multi-stage stratified cluster sampling method. Participants were 1,641 student and parent pairs from Grades 4, 5, and 6 of eight primary schools in Beijing. The following school types were included: state schools with migrant children comprising over 70% of total children (SMS), private schools with migrant children comprising over 70% (PMS), and state schools with permanent resident children comprising over 70% (SRS). Children were divided into Groups A, B, C or D by the type of school they attended (A and B were drawn from SRSs, C was from SMSs, and D was from PMSs) and whether they were in the migrant population (B, C, and D were, but A was not). Related information was collected through medical examination and questionnaires completed by parents and children. Prevalence of caries, overweight and obesity, poor vision, and self-reported incidence of colds and diarrhea in the previous month were explored as health outcomes. The results partially demonstrated the existence of the migrant paradox and verified the role of schools in lowering health disparities among children; there are theoretical and practical implications for improving the health of migrant children.

Trends in Socioeconomic Inequalities in Body Mass Index, Underweight and Obesity among English Children, 2007-2008 to 2011-2012

Background

Socioeconomic inequalities in childhood obesity have been reported in most developed countries, with obesity more common in deprived groups. Whether inequalities are found in the prevalence of underweight, the rest of the body mass index (BMI) distribution, or have changed across time is not clear.

Methods and Findings

The sample comprised 5,027,128 children on entry (4 to 5 years old) and leaving (10 to 11 years) state primary (elementary) school who participated in the National Child Measurement Programme (England, United Kingdom). We used area-level deprivation (Indices of Multiple Deprivation at the lower super output area) as a measure of socioeconomic deprivation. From 2007–2008 to 2011–2012 inequalities in obesity between the most compared to least deprived group increased (from 7.21% to 8.30%; p<0.001), whereas inequalities in the prevalence of underweight (1.50% to 1.21%; p = 0.15) were stable during this period. There were no differences by age group or by sex, but a three-way interaction suggested inequalities in obesity had increased at a faster rate for 10 to 11 year old girls, than 4 to 5 year old boys, (2.03% vs 0.07%; p<0.001 for interaction). Investigating inequalities across the distribution of zBMI showed increases in mean zBMI (0.18 to 0.23, p<0.001) could be attributed to increases in inequalities between the 50^th and 75^th centiles of BMI. Using the 2011 to 2012 population attributable risk estimates, if inequalities were halved, 14.04% (95% CI 14.00% to 14.07%) of childhood obesity could be avoided.

Conclusions

Socioeconomic inequalities in childhood obesity and zBMI increased in England between 2007–2008 and 2011–2012. Inequalities in the prevalence of underweight did not change. Traditional methods of examining inequalities only at the clinical thresholds of overweight and obesity may have led the magnitude of inequalities in childhood BMI to be underestimated.

Trends in childhood obesity and central adiposity between 1998-2001 and 2010-2012 according to household income and urbanity in Korea

BACKGROUND

This study examined trends in body mass index (BMI), waist circumference (WC), and childhood overweight and obesity prevalence between 1998-2001 and 2010-2012 according to household income and urbanity among nationally representative Korean children and adolescents aged 10-19.

METHODS

The repeated cross-sectional data from Korean National Health and Nutrition Examination Surveys in 1998-2001 and 2010-2012 were used. Gender specific trends in age-adjusted means of WC and BMI by household equivalized income and urbanity were compared between years. The age-standardized prevalence of childhood overweight and obesity was calculated using three international criteria (International Obesity Task Force, World Health Organization, US Centers for Disease Control and Prevention) and a Korean national reference standard.

RESULTS

Among boys, overall BMI and overweight prevalence increased between 1998-2001 and 2010-2012, while overall WC decreased. Clear gender differences were found in the relationship of childhood obesity metrics with household income and urbanity and the time trends of those relationships. Positive relationships between these parameters were found for boys while negative relationships appeared for girls. In addition, compared with the childhood obesity prevalence among boys in rural areas, the prevalence among boys in urban areas were slightly lower in 1998-2001 but became greater in 2010-2012.

CONCLUSIONS

This study revealed gender difference in the association of childhood obesity with household income and urbanity and its time trends. The long-term gender-specific monitoring of socioeconomic and urban-rural differences in childhood obesity measures is warranted in South Korea.

Trajectories of Body Mass Index from Young Adulthood to Middle Age among Canadian Men and Women

Knowledge regarding the heterogeneity of BMI trajectories is limited for the Canadian population. Using latent class growth modelling, four distinct BMI trajectories of individuals from young adulthood to middle age were identified for both women and men from the longitudinal data of the National Population Health Survey. The associations between BMI trajectories and the individuals’ sociodemographic characteristics and behavioural factors were also examined. Aboriginal women were found more likely to be in the long-term overweight or obese groups. It reveals that increased years of smoking, drinking, and being physically active were associated with lowering the BMI trajectory in all groups for both women and men, with some exceptions in the long-term normal weight group for men. Increased years of rural living, being employed, and living with low income were associated with raising the BMI trajectory in all groups for women and in some groups for men. Food insecurity was associated with raising the BMI trajectory in each group for both women and men.

Why are poorer children at higher risk of obesity and overweight? A UK cohort study

Background: There is limited evidence on which risk factors attenuate income inequalities in child overweight and obesity; whether and why these inequalities widen as children age. Method: Eleven thousand nine hundred and sixty five singletons had complete data at age 5 and 9384 at age 11 from the Millennium Cohort Study (UK). Overweight (age 5 : 15%; age 11 : 20%) and obesity (age 5 : 5%; age 11 : 6%) were defined using the International Obesity Taskforce body mass index cut-points. To measure socioeconomic inequalities, we used quintiles of family income and as risk factors, we considered markers of maternal health behaviours and of children’s physical activity, sedentary behaviours and diet. Binary and multinomial logistic regression models were used. Results: The unadjusted analyses revealed stark income inequalities in the risk of obesity at age 5 and 11. At age 5, children in the bottom income quintile had 2.0 (95% CI: 1.4–2.8) increased relative risk of being obese whilst at age 11 they had 3.0 (95% CI: 2.0–4.5) increased risk compared to children in the top income quintile. Similar income inequalities in the risk of overweight emerged by age 11. Physical activity and diet were particularly important in explaining inequalities. Income inequalities in obesity and overweight widened significantly between age 5 and 11 and a similar set of risk factors protected against upward and promoted downward movements across weight categories. Conclusions: To reduce income inequalities in overweight and obesity and their widening across childhood the results support the need of early interventions which take account of multiple risk factors.

Socioeconomic Status and Overweight: A Population-Based Cross-Sectional Study of Japanese Children and Adolescents

BACKGROUND

Socioeconomic status (SES) as a determinant of obesity has received scant attention in Japan. This study examined the association between SES and overweight among Japanese children and adolescents.

METHODS

Cross-sectional analyses of a representative sample of Japanese children (6-11 years: n = 397) and adolescents (12-18 years: n = 397) were performed, with measured heights and weights from the 2010 National Health and Nutrition Examination Survey and the 2010 Comprehensive Survey of Living Conditions. Overweight, including obesity, was defined by International Obesity Task Force cut-offs. SES indicators included household income, equivalent household expenditure, parental educational attainment, and parental occupational class.

RESULTS

Overweight prevalence was 12.3% in children and 9.1% in adolescents. Adolescents living in middle-income households were more likely to be overweight than those living in high-income households (OR 2.26, 95% CI, 1.01-5.67) after adjustment for age, sex, and parental weight status. Similarly, adolescents living in households with low expenditure levels were more likely to be overweight than those living in households with high expenditure levels (OR 3.40, 95% CI, 1.20-9.60). In contrast, no significant association was observed among children.

CONCLUSIONS

Our results indicated that low household economic status was associated with being overweight, independent of parental weight status, among Japanese adolescents.

Do neighborhood characteristics in Amsterdam influence adiposity at preschool age?

Background: Neighborhood characteristics may contribute to adiposity in young children, but results in the current literature are inconsistent. This study aimed to investigate whether objective (socioeconomic status (SES)) and subjective (perceived safety, satisfaction with green spaces and perceived physical disorder) neighborhood characteristics directly influence child adiposity (as measured by BMI, percent body fat (%BF) and waist-to-height ratio (WHtR)). Methods: Data on child BMI, %BF and WHtR were obtained from the Amsterdam Born Children and their Development cohort at 5–6 years of age. Three thousand four hundred and sixty nine (3469) children were included in the analyses. Mixed models, using random intercepts for postal code area to account for neighborhood clustering effects, were used to analyze the relationships of interest. Results: Associations were observed for both perceived safety and neighborhood SES with %BF after adjustment for maternal education and ethnicity. All relationships were eliminated with the inclusion of individual covariates and parental BMI into the models. Conclusions: In general, child adiposity at age 5–6 years was not independently associated with neighborhood characteristics, although a small relationship between child %BF and both neighborhood SES and perceived safety cannot be ruled out. At this young age, familial and individual factors probably play a more important role in influencing child adiposity than neighborhood characteristics.