School-based obesity prevention intervention in Chilean children: effective in controlling, but not reducing obesity

Impact of an educational intervention about healthy lifestyles in teenagers

BACKGROUND

During the last years, lifestyle has worsened along the entire European population, causing an alarming boom-up regarding overweight and obese people. Pediatric population is also influenced in this sense, which may predispose to suffer from several diseases in adulthood. Educational interventions at early ages could be an effective strategy to face this situation.

AIM

To describe the impact of an educational intervention about healthy lifestyle in adolescents.

METHODS

A quasi-experimental study analyzing the knowledge of high school students, before and after a brief educational intervention based on a self-elaborated questionnaire including questions from the validated questionnaire CAPA (from Spanish, Conocimientos en Alimentación de Personas Adolescentes).

RESULTS

The results of this study show a significant increase in knowledge about healthy lifestyles in the study population after the educational intervention (14.3±3.8 vs. 16.5±4.5; p<0.001). In addition, this improvement presents an asymmetric distribution according to gender (13.2±3.6 vs. 14.9±4.6; p=0.002 in men; 15.6±3 vs. 18.1±3.6; p<0.001 in women) and the type of educational center (14.17±3.6 vs. 16.48±4.17; p<0.001 in public schools and 14.86±4.15 vs. 16.54±5.32; p=0.047 in private schools). Parents' educational level was associated with improvement in knowledge about healthy lifestyles (13.44±2.9 vs. 15.67±5.37; p=0.132 at low level, 14.22±3.42 vs. 16.9±4.68; p<0.001 at medium level and 15.75±3.3 vs. 17.39±4.5; p=0.022 at high level).

CONCLUSION

Educational intervention taught by primary health care professionals is a useful and efficient tool for the acquisition of nutritional and healthy lifestyle knowledge in adolescents.

Childhood obesity prevention trials: A systematic review and meta-analysis on trial design and the impact of type 1 error

Effect sizes from previously reported trials are often used to determine the meaningful change in weight in childhood obesity prevention interventions because information on clinically meaningful differences is lacking. Estimates from previous trials may be influenced by statistical significance; therefore, it is important that they have a low risk of type 1 error. A systematic review and meta-analysis were conducted to report on the design of child obesity prevention randomized controlled trials and effectiveness according to risk of type 1 error. Eighty-four randomized controlled trials were identified. A large range of assumptions were applied in the sample size calculations. The most common primary outcome was BMI, with detectable effect size differences used in sample size calculations ranging from 0.25 kg/m2 (followed up at 2 years) to 1.1 kg/m2 (at 9 months) and BMI z-score ranging from 0.1 (at 4 years) to 0.67 (at 3 years). There was no consistent relationship between low risk of type 1 error and reports of higher or lower effectiveness. Further clarity of the size of a meaningful difference in weight in childhood obesity prevention trials is required to support evaluation design and decision-making for intervention and policy. Type 1 error risk does not appear to impact effect sizes in a consistent direction.

Interventions to prevent obesity in children aged 5 to 11 years old

BACKGROUND

Prevention of obesity in children is an international public health priority given the prevalence of the condition (and its significant impact on health, development and well-being). Interventions that aim to prevent obesity involve behavioural change strategies that promote healthy eating or 'activity' levels (physical activity, sedentary behaviour and/or sleep) or both, and work by reducing energy intake and/or increasing energy expenditure, respectively. There is uncertainty over which approaches are more effective and numerous new studies have been published over the last five years, since the previous version of this Cochrane review.

OBJECTIVES

To assess the effects of interventions that aim to prevent obesity in children by modifying dietary intake or 'activity' levels, or a combination of both, on changes in BMI, zBMI score and serious adverse events.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was February 2023.

SELECTION CRITERIA

Randomised controlled trials in children (mean age 5 years and above but less than 12 years), comparing diet or 'activity' interventions (or both) to prevent obesity with no intervention, usual care, or with another eligible intervention, in any setting. Studies had to measure outcomes at a minimum of 12 weeks post baseline. We excluded interventions designed primarily to improve sporting performance.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our outcomes were body mass index (BMI), zBMI score and serious adverse events, assessed at short- (12 weeks to < 9 months from baseline), medium- (9 months to < 15 months) and long-term (≥ 15 months) follow-up. We used GRADE to assess the certainty of the evidence for each outcome.

MAIN RESULTS

This review includes 172 studies (189,707 participants); 149 studies (160,267 participants) were included in meta-analyses. One hundred forty-six studies were based in high-income countries. The main setting for intervention delivery was schools (111 studies), followed by the community (15 studies), the home (eight studies) and a clinical setting (seven studies); one intervention was conducted by telehealth and 31 studies were conducted in more than one setting. Eighty-six interventions were implemented for less than nine months; the shortest was conducted over one visit and the longest over four years. Non-industry funding was declared by 132 studies; 24 studies were funded in part or wholly by industry. Dietary interventions versus control Dietary interventions, compared with control, may have little to no effect on BMI at short-term follow-up (mean difference (MD) 0, 95% confidence interval (CI) -0.10 to 0.10; 5 studies, 2107 participants; low-certainty evidence) and at medium-term follow-up (MD -0.01, 95% CI -0.15 to 0.12; 9 studies, 6815 participants; low-certainty evidence) or zBMI at long-term follow-up (MD -0.05, 95% CI -0.10 to 0.01; 7 studies, 5285 participants; low-certainty evidence). Dietary interventions, compared with control, probably have little to no effect on BMI at long-term follow-up (MD -0.17, 95% CI -0.48 to 0.13; 2 studies, 945 participants; moderate-certainty evidence) and zBMI at short- or medium-term follow-up (MD -0.06, 95% CI -0.13 to 0.01; 8 studies, 3695 participants; MD -0.04, 95% CI -0.10 to 0.02; 9 studies, 7048 participants; moderate-certainty evidence). Five studies (1913 participants; very low-certainty evidence) reported data on serious adverse events: one reported serious adverse events (e.g. allergy, behavioural problems and abdominal discomfort) that may have occurred as a result of the intervention; four reported no effect. Activity interventions versus control Activity interventions, compared with control, may have little to no effect on BMI and zBMI at short-term or long-term follow-up (BMI short-term: MD -0.02, 95% CI -0.17 to 0.13; 14 studies, 4069 participants; zBMI short-term: MD -0.02, 95% CI -0.07 to 0.02; 6 studies, 3580 participants; low-certainty evidence; BMI long-term: MD -0.07, 95% CI -0.24 to 0.10; 8 studies, 8302 participants; zBMI long-term: MD -0.02, 95% CI -0.09 to 0.04; 6 studies, 6940 participants; low-certainty evidence). Activity interventions likely result in a slight reduction of BMI and zBMI at medium-term follow-up (BMI: MD -0.11, 95% CI -0.18 to -0.05; 16 studies, 21,286 participants; zBMI: MD -0.05, 95% CI -0.09 to -0.02; 13 studies, 20,600 participants; moderate-certainty evidence). Eleven studies (21,278 participants; low-certainty evidence) reported data on serious adverse events; one study reported two minor ankle sprains and one study reported the incident rate of adverse events (e.g. musculoskeletal injuries) that may have occurred as a result of the intervention; nine studies reported no effect. Dietary and activity interventions versus control Dietary and activity interventions, compared with control, may result in a slight reduction in BMI and zBMI at short-term follow-up (BMI: MD -0.11, 95% CI -0.21 to -0.01; 27 studies, 16,066 participants; zBMI: MD -0.03, 95% CI -0.06 to 0.00; 26 studies, 12,784 participants; low-certainty evidence) and likely result in a reduction of BMI and zBMI at medium-term follow-up (BMI: MD -0.11, 95% CI -0.21 to 0.00; 21 studies, 17,547 participants; zBMI: MD -0.05, 95% CI -0.07 to -0.02; 24 studies, 20,998 participants; moderate-certainty evidence). Dietary and activity interventions compared with control may result in little to no difference in BMI and zBMI at long-term follow-up (BMI: MD 0.03, 95% CI -0.11 to 0.16; 16 studies, 22,098 participants; zBMI: MD -0.02, 95% CI -0.06 to 0.01; 22 studies, 23,594 participants; low-certainty evidence). Nineteen studies (27,882 participants; low-certainty evidence) reported data on serious adverse events: four studies reported occurrence of serious adverse events (e.g. injuries, low levels of extreme dieting behaviour); 15 studies reported no effect. Heterogeneity was apparent in the results for all outcomes at the three follow-up times, which could not be explained by the main setting of the interventions (school, home, school and home, other), country income status (high-income versus non-high-income), participants' socioeconomic status (low versus mixed) and duration of the intervention. Most studies excluded children with a mental or physical disability.

AUTHORS' CONCLUSIONS

The body of evidence in this review demonstrates that a range of school-based 'activity' interventions, alone or in combination with dietary interventions, may have a modest beneficial effect on obesity in childhood at short- and medium-term, but not at long-term follow-up. Dietary interventions alone may result in little to no difference. Limited evidence of low quality was identified on the effect of dietary and/or activity interventions on severe adverse events and health inequalities; exploratory analyses of these data suggest no meaningful impact. We identified a dearth of evidence for home and community-based settings (e.g. delivered through local youth groups), for children living with disabilities and indicators of health inequities.

Interventions to prevent obesity in school-aged children 6-18 years: An update of a Cochrane systematic review and meta-analysis including studies from 2015-2021

BACKGROUND

Childhood obesity remains a global public health priority due to the enormous burden it generates. Recent surveillance data suggests there has been a sharp increase in the prevalence of childhood obesity during the COVID-19 pandemic. The Cochrane review of childhood obesity prevention interventions (0-18 years) updated to 2015 is the most rigorous and comprehensive review of randomised controlled trials (RCTs) on this topic. A burgeoning number of high quality studies have been published since that are yet to be synthesised.

METHODS

An update of the Cochrane systematic review was conducted to include RCT studies in school-aged children (6-18 years) published to 30 June 2021 that assessed effectiveness on child weight (PROSPERO registration: CRD42020218928). Available cost-effectiveness and adverse effect data were extracted. Intervention effects on body mass index (BMI) were synthesised in random effects meta-analyses by setting (school, after-school program, community, home), and meta-regression examined the association of study characteristics with intervention effect.

FINDINGS

Meta-analysis of 140 of 195 included studies (183,063 participants) found a very small positive effect on body mass index for school-based studies (SMD -0·03, 95%CI -0·06,-0·01; trials = 93; participants = 131,443; moderate certainty evidence) but not after-school programs, community or home-based studies. Subgroup analysis by age (6-12 years; 13-18 years) found no differential effects in any setting. Meta-regression found no associations between study characteristics (including setting, income level) and intervention effect. Ten of 53 studies assessing adverse effects reported presence of an adverse event. Insufficient data was available to draw conclusions on cost-effectiveness.

INTERPRETATION

This updated synthesis of obesity prevention interventions for children aged 6-18 years, found a small beneficial impact on child BMI for school-based obesity prevention interventions. A more comprehensive assessment of interventions is required to identify mechanisms of effective interventions to inform future obesity prevention public health policy, which may be particularly salient in for COVID-19 recovery planning.

FUNDING

This research was funded by the National Health and Medical Research Council (NHMRC), Australia (Application No APP1153479).

Clinical and school-based intervention strategies for youth obesity prevention: A systematic review

Introduction

In the last couple of decades, numerous intervention strategies (ISs) have been formulated in school/community or clinical sectors using physical activity (PA) in order to prevent youth obesity because they have been highly effective in addressing this issue. These two sectors have revealed some interesting information in terms of efficient results and best practice mechanisms, but comparisons between them to learn about their functioning have been rare.

Methods

Therefore, the aim of this systematic review was to analyze and synthesize PA ISs from school/community or clinical domains for the period 2013-2017, in French or English, targeting youths aged 5-19 years old through primary, secondary, and tertiary prevention.

Results

In total, 68 full articles were reserved for data extraction and synthesis and 617 were excluded because they did not meet eligibility criteria (61 of 68 were kept for the final analysis). The results identified a number of differences between the studies of the various IS sectors and also a third type of IS, mixed sector. Mixed ISs (clinical and school-community) have a special advantage because they can benefit from the strengths of both school/community-based and clinical-based ISs. Mixed ISs showed the most promising results. This review also highlighted the differences between sectors and their ISs in terms of intervention teams, prevention objectives, duration, materials, and efficiency.

Conclusion

Future studies should focus on establishing a prevention program in a given geographical area involving all stakeholders with their respective skills/knowledge, in the area of decision-making and in the development of ISs, to ensure that the program is the most efficient and best adapted to its environment.

Systematic Review of Setting-Based Interventions for Preventing Childhood Obesity

Introduction

Child obesity is recognized as one of the major public health problems globally, which demands multicomponent and comprehensive interventions. The objective of this systematic review is to evaluate, synthesize, and combine the existing evidence of various setting-based interventions across developed and developing countries that aim to prevent childhood obesity.

Methods

An electronic and systematic search was conducted on setting-based interventions related to childhood obesity both in developed and developing countries. A study was considered eligible if it was a randomized controlled trial that focused on home-based, school-based, or community-based intervention for childhood obesity and published in English from 2010 to 2020. A wide range of electronic bibliographic databases, such as PubMed, Medline, Embase, and ERIC were searched. The various studies were carried out among children aged 4-18 years old. A total of 32 studies were identified; out of which 24 were school-based interventions, and the remaining were nonschool-based.

Results

The studies in this review highlighted important school and nonschool-based interventions to avoid obesity among children and adolescents. School-based interventions that had considered both physical activity (PA) and diet along with home elements showed great effectiveness. These findings reveal that the specific intervention components such as nutrition education curriculum, prolonged time for PA, and upgrading self-efficacy of study participants should be considered to prevent obesity across developed and developing countries. However, the findings from nonschool-based interventions were restricted by the scarcity of the studies.

Conclusion

Multisetting and multipronged strategies are required to avoid or reduce childhood obesity across the globe. However, additional studies are needed with a large sample size. Further study designs based on theory should be conducted in nonschool settings for the creation of meaningful and detailed guidelines that can support the prevention of obesity in children.

[Entorno social y obesidad infantil: implicaciones para la investigación y la práctica en Estados Unidos y en los países latinoamericanos]

The environments of children influence their risk for childhood obesity through, among other factors, a child's weight-related behaviors (i.e., diet and physical activity). In this article, we present evidence on social environmental factors associated with a child's diet and physical activity, and more generally, the prevention and control of childhood obesity among Hispanic/Latinx children in the United States and children from countries in Latin America. Using a socio-ecologic lens, we present evidence from cross-sectional and longitudinal studies conducted in the United States involving Hispanic/Latinx children, and evidence from studies involving children in Latin America. Studies examining parenting factors in the home environment (e.g., parenting strategies) are especially emphasized, with more limited evidence on social environmental factors in other lived contexts (e.g., school). The influence of acculturation on social relationships cuts across levels of the socio-ecological framework. Intervention research identified strategies and research gaps for intervening on social factors to promote healthy behaviors and reduce risk for childhood obesity. Community health workers and others forms of peer support were identified as relevant approaches at multiple levels of the socio-ecological framework. This article concludes with directions for future research to further understand the environment using newer information and communication technologies.

Physiotherapy and related management for childhood obesity: A systematic scoping review

INTRODUCTION

Despite targeted efforts globally to address childhood overweight/obesity, it remains poorly understood and challenging to manage. Physiotherapists have the potential to manage children with obesity as they are experts in movement and physical activity. However, their role remains unclear due to a lack of physiotherapy-specific guidelines. This scoping review aims to explore existing literature, critically appraising and synthesising findings to guide physiotherapists in the evidence-based management of childhood overweight/obesity.

METHOD

A scoping review was conducted, including literature up to May 2020. A review protocol exists on Open Science Framework at https://osf.io/fap8g/. Four databases were accessed including PubMed, Embase, CINAHL, Medline via OVID, with grey literature searched through google via "file:pdf". A descriptive synthesis was undertaken to explore the impact of existing interventions and their efficacy.

RESULTS

From the initial capture of 1871 articles, 263 intervention-based articles were included. Interventions included qualitative focused physical activity, quantitative focused physical activity and multicomponent interventions. Various outcome measures were utilised including health-, performance- and behaviour-related outcomes. The general trend for physiotherapy involvement with children who are obese appears to favour: 1) multicomponent interventions, implementing more than one component with environmental modification and parental involvement and 2) quantitative physical activity interventions, focusing on the quantity of bodily movement. These approaches most consistently demonstrated desirable changes across behavioural and health-related outcome measures for multicomponent and quantitative physical activity interventions respectively.

CONCLUSION

When managing children with obesity, physiotherapists should consider multicomponent approaches and increasing the quantity of physical activity, given consistent improvements in various obesity-related outcomes. Such approaches are well suited to the scope of physiotherapists and their expertise in physical activity prescription for the management of childhood obesity. Future research should examine the effect of motor skill interventions and consider the role of environmental modification/parental involvement as factors contributing to intervention success.

The Effectiveness of School-Based Interventions on Obesity-Related Behaviours in Primary School Children: A Systematic Review and Meta-Analysis of Randomised Controlled Trials

School-based interventions are promising for targeting a change in obesity-related behaviours in children. However, the efficacy of school-based interventions to prevent obesity remains unclear. This review examined the effectiveness of school-based interventions at changing obesity-related behaviours (increased physical activity, decreased sedentary behaviour and improved nutrition behaviour) and/or a change in BMI/BMI z-score. Following PRISMA guidelines, seven databases were systematically searched from 1 January 2009 to 31 December 2020. Two review authors independently screened studies for eligibility, completed data extraction and assessed the risk of bias of each of the included studies. Forty-eight studies met the inclusion criteria and were included in a narrative synthesis. Thirty-eight studies were eligible for inclusion in a meta-analysis. The findings demonstrate that interventions in children when compared to controls resulted in a small positive treatment effect in the control group (2.14; 95% CI = 0.77, 3.50). There was no significant effect on sedentary behaviour, energy intake and fruit and vegetable intake. Significant reductions were found between groups in BMI kg/m2 (-0.39; 95% CI = -0.47, -0.30) and BMI z-score (-0.05; 95% CI = -0.08, -0.02) in favour of the intervention. The findings have important implications for future intervention research in terms of the effectiveness of intervention components and characteristics.

Sin taxes and their effect on consumption, revenue generation and health improvement: a systematic literature review in Latin America

Sin or public health taxes are excise taxes imposed on the consumption of potentially harmful goods for health [sugar-sweetened beverages (SSBs), tobacco, alcohol, among others], aiming to reduce consumption, raise additional revenue and/or improve population health. This paper assesses the extent to which sin taxes (a) can reduce consumption of potentially harmful goods, (b) raise revenue for national health systems and (c) contribute to population health in Latin America. A systematic literature review was conducted on peer-reviewed and grey literature; endpoints included: impact of raising sin taxes on consumption, ability to raise revenue for health and the possibility of population health improvements. Risk of bias for each study was assessed. The synthesis of the literature on sin tax implementation showed improvements in all three endpoints across the study countries. Following the introduction of sin taxes or by simulating their potential impact, nearly all studies explicitly reported that consumption of potentially harmful goods (mainly SSBs and tobacco) declined; revenue was found to have increased in almost all countries, suggesting that there may be additional scope for further tax increase. Simulated improvements in population health have also been shown, by demonstrating a relationship between sin tax increases and reduction in prevalence of diabetes, stroke, heart attacks and associated deaths. However, sin tax effects on health would be better quantified over the long-term. Data quality and availability challenges did place some limitations on sin tax impact assessment. Sin taxes can be effective in reducing consumption of potentially harmful goods, improve population health and generate additional revenue. Promoting further research on this topic should be a priority.

The social environment and childhood obesity: Implications for research and practice in the United States and countries in Latin America

The environments of children influence their risk for childhood obesity through, among other factors, a child's weight-related behaviors (i.e., diet and physical activity). In this article, we present evidence on social environmental factors associated with a child's diet and physical activity, and more generally, the prevention and control of childhood obesity among Hispanic/Latinx children in the United States and children from countries in Latin America. Using a socio-ecologic lens, we present evidence from cross-sectional and longitudinal studies conducted in the United States involving Hispanic/Latinx children, and evidence from studies involving children in Latin America. Studies examining parenting factors in the home environment (e.g., parenting strategies) are especially emphasized, with more limited evidence on social environmental factors in other lived contexts (e.g., school). The influence of acculturation on social relationships cuts across levels of the socio-ecological framework. Intervention research identified strategies and research gaps for intervening on social factors to promote healthy behaviors and reduce risk for childhood obesity. Community health workers and others forms of peer support were identified as relevant approaches at multiple levels of the socio-ecological framework. This article concludes with directions for future research to further understand the environment using newer information and communication technologies.

Cross-Sectional and Longitudinal Associations between Non-School Time Physical Activity, Sedentary Time, and Adiposity among Boys and Girls: An Isotemporal Substitution Approach

This study investigated the cross-sectional and longitudinal associations of the substitution of non-school time light physical activity (LPA), moderate-to-vigorous physical activity (MVPA), and sedentary time (ST) with adiposity in boys and girls. Boys (n = 65, baseline Mage= 9.93 ± 0.86 years) and girls (n = 77, baseline Mage = 10.17 ± 0.95 years) wore waist-worn accelerometers (ActiGraph GT3X) at baseline and at a 30-month follow-up, from which non-school time LPA, MVPA, ST, and total device wear were quantified. Body mass index (BMI) and waist-to-height-ratio (WHR) were measured at baseline and follow-up. Body fat percent (BF%) was obtained at follow-up only. Isotemporal substitution models assessed the cross-sectional and longitudinal associations of reallocating non-school time activity with BMI, WHR and BF%. In boys, replacing 30 min/day of LPA with MVPA was cross-sectionally (β = −8.26, p < 0.05) associated with a lower BF%. Replacing 30 min/day of ST with MVPA was cross-sectionally (β = −6.02, p < 0.05) associated with a lower BF% in boys. Longitudinally in boys, replacing 30 min of change in LPA with MVPA (β = −7.42, p < 0.10) and replacing 30 min of change in MVPA with ST (β = 5.78, p < 0.10) over 30 months was marginally associated with less BF%. Associations were null in girls (p > 0.05). These results may support targeting activity reallocation during non-school time for the purposes of adiposity improvement in boys. A multi-behavioral approach may be more appropriate for girls, as non-school time activity may not be driving adiposity status.

Interventions to prevent obesity in Latinx children globally: protocol for a systematic review and meta-analysis

BACKGROUND

Rates of childhood obesity have accelerated rapidly over the past decade in low- and middle-income countries and in Latin America in particular. At the same time, Latinx children in high-income countries have been disproportionately affected by obesity. Public health and medical experts have called for greater focus on multi-sector approaches to obesity prevention, including policy, systems, and environmental strategies, but current evidence for effective intervention strategies among Latinx children is lacking. Several systematic reviews have investigated obesity prevention interventions in Latinx children in the United States and in Latin America, including our own review, but these are now a decade old. Thus, an updated review of existing interventions is needed. To address this gap, we will conduct a systematic review and summary of interventions for obesity prevention among Latinx children published over the past 10 years. The objective of this paper is to outline the protocol for conducting the systematic review and possible meta-analysis.

METHODS

We will conduct a literature search using PubMed, ERIC, PsycINFO, Scopus, Scientific Electronic Library Online, and Google Scholar databases for studies of interventions to prevent obesity in Latinx children ages birth to 18 years of age. To meet our definition of an intervention, we will include study designs that evaluate the either the efficacy or effectiveness of obesity prevention interventions, including randomized controlled trials, quasi-experimental studies, and non-randomized interventions with a control or comparison group. We will exclude interventions that aimed to treat rather than prevent overweight or obesity. Interventions may take place in any country or setting. The primary outcome of interest will be child overweight or obesity, measured as adiposity, body mass, or similar anthropometric measures. We will assess risk of bias of included studies using the Cochrane risk of bias tool for randomized and non-randomized studies, as appropriate. We may conduct meta-analyses if studies with comparable exposure and outcome variables are available.

DISCUSSION

This protocol paper establishes a methodology for a future systemic review of obesity prevention interventions in Latinx children. A systematic review of this topic will provide an important update to the literature regarding interventions to prevent obesity in Latinx child populations globally over the past decade. Review results will be relevant to stakeholders across multiple sectors engaged in childhood obesity prevention among Latinx children.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42020161339.

Effectiveness of dietary interventions on weight outcomes in childhood: a systematic review meta-analysis of randomized controlled trials

BACKGROUND

Rapid growth and elevated weight in childhood are significantly associated with obesity in later life, but evidence regarding dietary interventions and weight outcomes is lacking. This study aimed to determine the effectiveness of dietary interventions on body mass index (BMI) and BMI z-score in childhood.

METHODS

PubMed, EmBase, and the Cochrane library were searched from inception till June 2019. Studies that investigated the effectiveness of dietary interventions on BMI and BMI z-score in childhood were considered eligible in our study. The changes in BMI and BMI z-score between dietary interventions and control were calculated by pooled weighted mean differences (WMDs) and 95% CIs were evaluated using random-effects model.

RESULTS

Twenty-eight randomized controlled trials involving a total of 17,488 children were included. The summary WMDs indicated that children who received dietary interventions had greater reduction in BMI (WMD: -0.12; 95% CI: -0.20 to -0.05; P=0.001) and BMI z-score (WMD: -0.04; 95% CI: -0.06 to -0.02; P=0.001) when compared to the usual controls. Subgroup analyses revealed that the sample size, mean age, duration of interventions, and study quality could affect the effectiveness of dietary interventions in children.

CONCLUSIONS

The findings of this meta-analysis suggested that dietary interventions improved BMI and BMI z-score, whereas these results are limited due to substantial heterogeneity and study quality of the included studies.

Long-Term Dietary and Physical Activity Interventions in the School Setting and Their Effects on BMI in Children Aged 6-12 Years: Meta-Analysis of Randomized Controlled Clinical Trials

Preventive actions and potential obesity interventions for children are mainly researched throughout the school period, either as part of the school curricula or after regular school hours, via interventions mostly lasting less than 12 months. We aimed to perform a meta-analysis on randomized controlled clinical trials to evaluate the evidence of the efficacy of long-term school-based interventions in the management of childhood obesity in terms of BMI from a dietary and physical activity-based approach. Eleven randomized controlled clinical trials were examined using the random effects model, and the results showed that there were no significant effects associated with physical activity + nutrition intervention in school children aged 6-12 years, with a pooled standardized mean difference (SMD) (95% CI) of -0.00 (-0.05, 0.04). No effects were observed after subgroup analysis based on the intervention length. The findings from our study indicate that long-term school-based interventions on physical activity and dietary habits received by children aged 6-12 years seem to have no effect on BMI. However, the promotion of such interventions should not be discouraged, as they promote additional positive health outcomes for other domains of children's health.

Identification and evaluation of risk of generalizability biases in pilot versus efficacy/effectiveness trials: a systematic review and meta-analysis

BACKGROUND

Preliminary evaluations of behavioral interventions, referred to as pilot studies, predate the conduct of many large-scale efficacy/effectiveness trial. The ability of a pilot study to inform an efficacy/effectiveness trial relies on careful considerations in the design, delivery, and interpretation of the pilot results to avoid exaggerated early discoveries that may lead to subsequent failed efficacy/effectiveness trials. "Risk of generalizability biases (RGB)" in pilot studies may reduce the probability of replicating results in a larger efficacy/effectiveness trial. We aimed to generate an operational list of potential RGBs and to evaluate their impact in pairs of published pilot studies and larger, more well-powered trial on the topic of childhood obesity.

METHODS

We conducted a systematic literature review to identify published pilot studies that had a published larger-scale trial of the same or similar intervention. Searches were updated and completed through December 31st, 2018. Eligible studies were behavioral interventions involving youth (≤18 yrs) on a topic related to childhood obesity (e.g., prevention/treatment, weight reduction, physical activity, diet, sleep, screen time/sedentary behavior). Extracted information included study characteristics and all outcomes. A list of 9 RGBs were defined and coded: intervention intensity bias, implementation support bias, delivery agent bias, target audience bias, duration bias, setting bias, measurement bias, directional conclusion bias, and outcome bias. Three reviewers independently coded for the presence of RGBs. Multi-level random effects meta-analyses were performed to investigate the association of the biases to study outcomes.

RESULTS

A total of 39 pilot and larger trial pairs were identified. The frequency of the biases varied: delivery agent bias (19/39 pairs), duration bias (15/39), implementation support bias (13/39), outcome bias (6/39), measurement bias (4/39), directional conclusion bias (3/39), target audience bias (3/39), intervention intensity bias (1/39), and setting bias (0/39). In meta-analyses, delivery agent, implementation support, duration, and measurement bias were associated with an attenuation of the effect size of - 0.325 (95CI - 0.556 to - 0.094), - 0.346 (- 0.640 to - 0.052), - 0.342 (- 0.498 to - 0.187), and - 0.360 (- 0.631 to - 0.089), respectively.

CONCLUSIONS

Pre-emptive avoidance of RGBs during the initial testing of an intervention may diminish the voltage drop between pilot and larger efficacy/effectiveness trials and enhance the odds of successful translation.

A systematic review and meta-analysis of the overall effects of school-based obesity prevention interventions and effect differences by intervention components

Background

Childhood obesity is a serious public health concern. School-based interventions hold great promise to combat the rising trend of childhood obesity. This systematic review aimed to assess the overall effects of school-based obesity prevention interventions, and to investigate characteristics of intervention components that are potentially effective for preventing childhood obesity.

Methods

We systematically searched MEDLINE, CENTRAL and Embase databases to identify randomized- or cluster randomized- controlled trials of school-based obesity interventions published between 1990 and 2019. We conducted meta-analyses and subgroup analyses to determine the overall effects of obesity prevention programs and effect differences by various characteristics of intervention components on body mass index (BMI) or BMI Z-score of children.

Results

This systematic review included a total of 50 trials (reported by 56 publications). Significant differences were found between groups on BMI (− 0.14 kg/m² (95% confidence interval: − 0.21, − 0.06)) and BMI Z-score (− 0.05 (− 0.10, − 0.01)) for single-component interventions; significant differences were also found between groups on BMI (− 0.32 (− 0.54, − 0.09) kg/m²) and BMI Z-score (− 0.07 (− 0.14, − 0.001)) for multi-component interventions. Subgroup analyses consistently demonstrated that effects of single-component (physical activity) interventions including curricular sessions (− 0.30 (− 0.51, − 0.10) kg/m² in BMI) were stronger than those without curricular sessions (− 0.04 (− 0.17, 0.09) kg/m² in BMI); effects of single-component (physical activity) interventions were also strengthened if physical activity sessions emphasized participants’ enjoyment (− 0.19 (− 0.33, − 0.05) kg/m² in BMI for those emphasizing participants’ enjoyment; − 0.004 (− 0.10, 0.09) kg/m² in BMI for those not emphasizing participants’ enjoyment). The current body of evidence did not find specific characteristics of intervention components that were consistently associated with improved efficacy for multi-component interventions (P > 0.05).

Conclusions

School-based interventions are generally effective in reducing excessive weight gain of children. Our findings contribute to increased understandings of potentially effective intervention characteristics for single-component (physical activity) interventions. The impact of combined components on effectiveness of multi-component interventions should be the topic of further research. More high-quality studies are also needed to confirm findings of this review.

Interventions for preventing obesity in children

BACKGROUND

Prevention of childhood obesity is an international public health priority given the significant impact of obesity on acute and chronic diseases, general health, development and well-being. The international evidence base for strategies to prevent obesity is very large and is accumulating rapidly. This is an update of a previous review.

OBJECTIVES

To determine the effectiveness of a range of interventions that include diet or physical activity components, or both, designed to prevent obesity in children.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, PsychINFO and CINAHL in June 2015. We re-ran the search from June 2015 to January 2018 and included a search of trial registers.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of diet or physical activity interventions, or combined diet and physical activity interventions, for preventing overweight or obesity in children (0-17 years) that reported outcomes at a minimum of 12 weeks from baseline.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data, assessed risk-of-bias and evaluated overall certainty of the evidence using GRADE. We extracted data on adiposity outcomes, sociodemographic characteristics, adverse events, intervention process and costs. We meta-analysed data as guided by the Cochrane Handbook for Systematic Reviews of Interventions and presented separate meta-analyses by age group for child 0 to 5 years, 6 to 12 years, and 13 to 18 years for zBMI and BMI.

MAIN RESULTS

We included 153 RCTs, mostly from the USA or Europe. Thirteen studies were based in upper-middle-income countries (UMIC: Brazil, Ecuador, Lebanon, Mexico, Thailand, Turkey, US-Mexico border), and one was based in a lower middle-income country (LMIC: Egypt). The majority (85) targeted children aged 6 to 12 years.Children aged 0-5 years: There is moderate-certainty evidence from 16 RCTs (n = 6261) that diet combined with physical activity interventions, compared with control, reduced BMI (mean difference (MD) -0.07 kg/m2, 95% confidence interval (CI) -0.14 to -0.01), and had a similar effect (11 RCTs, n = 5536) on zBMI (MD -0.11, 95% CI -0.21 to 0.01). Neither diet (moderate-certainty evidence) nor physical activity interventions alone (high-certainty evidence) compared with control reduced BMI (physical activity alone: MD -0.22 kg/m2, 95% CI -0.44 to 0.01) or zBMI (diet alone: MD -0.14, 95% CI -0.32 to 0.04; physical activity alone: MD 0.01, 95% CI -0.10 to 0.13) in children aged 0-5 years.Children aged 6 to 12 years: There is moderate-certainty evidence from 14 RCTs (n = 16,410) that physical activity interventions, compared with control, reduced BMI (MD -0.10 kg/m2, 95% CI -0.14 to -0.05). However, there is moderate-certainty evidence that they had little or no effect on zBMI (MD -0.02, 95% CI -0.06 to 0.02). There is low-certainty evidence from 20 RCTs (n = 24,043) that diet combined with physical activity interventions, compared with control, reduced zBMI (MD -0.05 kg/m2, 95% CI -0.10 to -0.01). There is high-certainty evidence that diet interventions, compared with control, had little impact on zBMI (MD -0.03, 95% CI -0.06 to 0.01) or BMI (-0.02 kg/m2, 95% CI -0.11 to 0.06).Children aged 13 to 18 years: There is very low-certainty evidence that physical activity interventions, compared with control reduced BMI (MD -1.53 kg/m2, 95% CI -2.67 to -0.39; 4 RCTs; n = 720); and low-certainty evidence for a reduction in zBMI (MD -0.2, 95% CI -0.3 to -0.1; 1 RCT; n = 100). There is low-certainty evidence from eight RCTs (n = 16,583) that diet combined with physical activity interventions, compared with control, had no effect on BMI (MD -0.02 kg/m2, 95% CI -0.10 to 0.05); or zBMI (MD 0.01, 95% CI -0.05 to 0.07; 6 RCTs; n = 16,543). Evidence from two RCTs (low-certainty evidence; n = 294) found no effect of diet interventions on BMI.Direct comparisons of interventions: Two RCTs reported data directly comparing diet with either physical activity or diet combined with physical activity interventions for children aged 6 to 12 years and reported no differences.Heterogeneity was apparent in the results from all three age groups, which could not be entirely explained by setting or duration of the interventions. Where reported, interventions did not appear to result in adverse effects (16 RCTs) or increase health inequalities (gender: 30 RCTs; socioeconomic status: 18 RCTs), although relatively few studies examined these factors.Re-running the searches in January 2018 identified 315 records with potential relevance to this review, which will be synthesised in the next update.

AUTHORS' CONCLUSIONS

Interventions that include diet combined with physical activity interventions can reduce the risk of obesity (zBMI and BMI) in young children aged 0 to 5 years. There is weaker evidence from a single study that dietary interventions may be beneficial.However, interventions that focus only on physical activity do not appear to be effective in children of this age. In contrast, interventions that only focus on physical activity can reduce the risk of obesity (BMI) in children aged 6 to 12 years, and adolescents aged 13 to 18 years. In these age groups, there is no evidence that interventions that only focus on diet are effective, and some evidence that diet combined with physical activity interventions may be effective. Importantly, this updated review also suggests that interventions to prevent childhood obesity do not appear to result in adverse effects or health inequalities.The review will not be updated in its current form. To manage the growth in RCTs of child obesity prevention interventions, in future, this review will be split into three separate reviews based on child age.

Effect of educational interventions on health in childhood: a meta-analysis of randomized controlled trials

OBJECTIVE

The purpose of this study was to summarize the findings of randomized controlled trials (RCTs) investigating any potential effects of educational interventions on health in childhood.

STUDY DESIGN

Meta-analysis.

METHODS

PubMed, Embase, and the Cochrane Library databases were searched to identify all RCTs that fit our analysis through May 2016. Weighted mean difference (WMD) was used to measure the effect of educational interventions in childhood by using a random effects model.

RESULTS

Thirty RCTs reporting data on 35,296 children were included in the meta-analysis. The summary WMD indicated that children who received educational interventions had lower levels of body mass index (BMI) (WMD: -0.15; 95% CI: -0.24 to -0.05; P = 0.003), BMI z-score (WMD: -0.03; 95% CI: -0.05 to -0.02; P < 0.001), waist circumference (WMD: -0.97; 95% CI: -1.95 to -0.00; P = 0.050), triceps skinfold (WMD: -1.39; 95% CI: -2.41 to -0.37; P = 0.008), systolic blood pressure (WMD: -1.13; 95% CI: -2.20 to -0.07; P = 0.037), total cholesterol (WMD: -4.04; 95% CI: -7.18 to -0.90; P = 0.012), and triglyceride (WMD: -2.62; 95% CI: -4.33 to -0.90; P = 0.003). However, educational interventions were found to have little or no significant impact on the waist-to-hip ratio, diastolic blood pressure, high-density lipoprotein, and low-density lipoprotein.

CONCLUSIONS

The study findings prove the positive effects of educational interventions on BMI, BMI z-score, waist circumference, triceps skinfold, systolic blood pressure, total cholesterol, and triglyceride.

Effect of educational interventions on health in childhood: A meta-analysis of randomized controlled trials

BACKGROUND

The purpose of this study was to summarize the evidences from randomized controlled trials (RCTs) investigating the effects of educational interventions in overweight/obesity childhood by using meta-analytic approach.

METHODS

PubMed, Embase, and the Cochrane Library databases were searched from the inception to April 2018. Weighted mean differences (WMDs) with corresponding 95% confidence intervals (CIs) were used to measure the effects of educational interventions during childhood in the random-effects models.

RESULTS

Thirty RCTs reporting data on 35,296 children were included in the meta-analysis. The summary WMD indicated that children received educational interventions had lower levels of body mass index (BMI) (WMD: -0.15; 95% CI: -0.24 to -0.05; P = .003), BMI z-score (WMD: -0.03; 95% CI: -0.05 to -0.02; P < .001), waist circumference (WMD: -0.97; 95% CI: -1.95 to -0.00; P = 0.050), triceps skinfold (WMD: -1.39; 95% CI: -2.41 to -0.37; P = .008), systolic blood pressure (WMD: -1.13; 95% CI: -2.20 to -0.07; P = .037), total cholesterol (WMD: -4.04; 95% CI: -7.18 to -0.90; P = .012), and triglyceride (WMD: -2.62; 95% CI: -4.33 to -0.90; P = .003). However, educational interventions were not associated with the levels of waist-to-hip ratio, diastolic blood pressure, high-density lipoprotein, and low-density lipoprotein.

CONCLUSION

The study findings elucidate the positive effects of educational interventions on BMI, BMI z-score, waist circumference, triceps skinfold, systolic blood pressure, total cholesterol, and triglyceride.

Interventions to prevent global childhood overweight and obesity: a systematic review

In view of the prevalence, health consequences, and costs of childhood obesity, there has been substantial interest in identifying effective interventions to prevent excess weight gain in young people. In this systematic review, we expand on previous reviews of obesity prevention interventions by including recent studies (until May 23, 2017) from all parts of the world. We searched MEDLINE, Embase, CINAHL Plus, Web of Science, CAB Abstracts, and PAIS Index and included randomised controlled trials, quasi-experimental studies, or natural experiments with: (1) a control group; (2) minimum follow-up of 12 months for community-based and home-based interventions or 6 months for school-based and preschool-based interventions; and (3) a primary outcome of BMI, BMI Z score, BMI percentile, body fat percentage, skinfold thickness, waist circumference, or prevalence of overweight or obesity. School-based interventions with combined diet and physical activity components and a home element (n=41) had greatest effectiveness; evidence in support of the effect of preschool-based (n=6), community-based (n=7), and home-based (n=2) interventions was limited by a paucity of studies and heterogeneity in study design. The effectiveness of school-based interventions that combined diet and physical activity components suggests that they hold promise for childhood obesity prevention worldwide. More research with rigorous evaluation and consistent reporting is needed in non-school settings and in combinations of settings.

Progress in physical activity over the Olympic quadrennium

On the eve of the 2012 summer Olympic Games, the first Lancet Series on physical activity established that physical inactivity was a global pandemic, and global public health action was urgently needed. The present paper summarises progress on the topics covered in the first Series. In the past 4 years, more countries have been monitoring the prevalence of physical inactivity, although evidence of any improvements in prevalence is still scarce. According to emerging evidence on brain health, physical inactivity accounts for about 3·8% of cases of dementia worldwide. An increase in research on the correlates of physical activity in low-income and middle-income countries (LMICs) is providing a better evidence base for development of context-relevant interventions. A finding specific to LMICs was that physical inactivity was higher in urban (vs rural) residents, which is a cause for concern because of the global trends toward urbanisation. A small but increasing number of intervention studies from LMICs provide initial evidence that community-based interventions can be effective. Although about 80% of countries reported having national physical activity policies or plans, such policies were operational in only about 56% of countries. There are important barriers to policy implementation that must be overcome before progress in increasing physical activity can be expected. Despite signs of progress, efforts to improve physical activity surveillance, research, capacity for intervention, and policy implementation are needed, especially among LMICs.

A Systematised Review of Primary School Whole Class Child Obesity Interventions: Effectiveness, Characteristics, and Strategies

Background. A systematised review was conducted to examine the effectiveness of school-based interventions that focus on changing dietary intake and physical activity levels to reduce childhood obesity. Methods. Multiple databases were searched for randomised and nonrandomised interventions from 2007 to 2016 in full-time elementary schools, which were delivered to the whole class, included dietary and physical activity components, involved both sexes, were written in English, and used body mass index (BMI) as an outcome. Results. The database search produced 8,866 titles from which 78 were deemed relevant and assessed for inclusion resulting in 15 studies meeting all inclusion criteria. From these 15 studies, 9 yielded a reduction or stabilisation in BMI or BMI z-score in the entire intervention group and/or subgroups. Programmes lasting between 6 and 12 months that involve multiple environmental, educational, and physical strategies appear to be most likely to result in BMI or BMI z-score improvement. Moderators most likely influencing an improvement in BMI included increased physical activity, decreased sugar sweetened beverages intake, and increased fruit intake. Conclusions. School-based interventions may be an effective means for child obesity prevention. The identification of consistent elements used in school-based interventions that have demonstrated effectiveness may aid in preventing child obesity.

Decreased Body Mass Index in Schoolchildren After Yearlong Information Sessions With Parents Reinforced With Web and Mobile Phone Resources: Community Trial

BACKGROUND

The obesity pandemic has now reached children, and households should change their lifestyles to prevent it.

OBJECTIVE

The objective was to assess the effect of a comprehensive intervention on body mass index z-score (BMIZ) in schoolchildren.

METHODS

A yearlong study was conducted at 4 elementary schools in Mexico City. Intervention group (IG) and control group (CG) were split equally between governmental and private schools. Three educational in-person parents and children sessions were held at 2-month intervals to promote healthy eating habits and exercise. To reinforce the information, a website provided extensive discussion on a new topic every 2 weeks, including school snack menus and tools to calculate body mass index in children and adults. Text messages were sent to parents' mobile phones reinforcing the information provided. The IG contained 226 children and CG 181 children. We measured their weight and height and calculated BMIZ at 0, 6, and 12 months.

RESULTS

The CG children showed a change of +0.06 (95% CI 0.01, 0.11) and +0.05 (95% CI 0.01, 0.10) in their BMIZ at 6 and 12 months, respectively. The BMIZ of IG children decreased by -0.13 (95% CI -0.19 to -0.06) and -0.10 (95% CI -0.16 to -0.03), respectively, and the effect was greater in children with obesity.

CONCLUSIONS

The comprehensive intervention tested had beneficial effects, preserved the BMIZ of normal weight children, and reduced the BMIZ of children with obesity.

Bariatric and Metabolic Surgery in Adolescents: a Path to Decrease Adult Cardiovascular Mortality

Obesity is a major health problem across all age groups and has escalated to pandemic proportions. The proportion of children with overweight or obesity has risen rapidly over recent decades, and it is recognized that most obese children become obese adults. Furthermore, BMI is the strongest CV risk factor to track from childhood into adulthood. As well as BMI, multiple CV risk factors begin in childhood and strong associations between these factors and BMI are evident. Clear evidence exists for the CV benefits of reversing obesity in adults, much of which examines the effects of bariatric surgery. The capacity of bariatric surgery to reliably achieve safe and lasting improvement in BMI is unparalleled, and the emerging evidence base in adolescent bariatric surgery has so far concurred. In the absence of effective alternatives, it appears that the increase in use of bariatric surgery in adolescents will continue.

Evaluation of physical activity interventions in children via the reach, efficacy/effectiveness, adoption, implementation, and maintenance (RE-AIM) framework: A systematic review of randomized and non-randomized trials

CONTEXT

Existing reviews of physical activity (PA) interventions designed to increase PA behavior exclusively in children (ages 5 to 11years) focus primarily on the efficacy (e.g., internal validity) of the interventions without addressing the applicability of the results in terms of generalizability and translatability (e.g., external validity).

OBJECTIVE

This review used the RE-AIM (Reach, Efficacy/Effectiveness, Adoption, Implementation, Maintenance) framework to measure the degree to which randomized and non-randomized PA interventions in children report on internal and external validity factors.

METHODS AND RESULTS

A systematic search for controlled interventions conducted within the past 12years identified 78 studies that met the inclusion criteria. Based on the RE-AIM criteria, most of the studies focused on elements of internal validity (e.g., sample size, intervention location and efficacy/effectiveness) with minimal reporting of external validity indicators (e.g., representativeness of participants, start-up costs, protocol fidelity and sustainability).

CONCLUSIONS

Results of this RE-AIM review emphasize the need for future PA interventions in children to report on real-world challenges and limitations, and to highlight considerations for translating evidence-based results into health promotion practice.

School-Based Interventions to Reduce Obesity Risk in Children in High- and Middle-Income Countries

School-based interventions are relatively new and were first introduced in the United States in the 1990s. Early programs were mainly education based with many of the findings now embedded in school policy in the form of a healthy eating curriculum. More recent school programs have taken education outside the classroom and attempted to engage parents as well as teachers. Environmental changes such as improving the quality of foods available at lunchtime and at other times during the school day are now common. Reviews of evaluations of school-based programs have demonstrated that they are effective and successfully improve dietary quality such as increasing fruit and vegetable intake and decreasing sweet and savory snacks and sweetened drinks; not just in school but over the whole day and particularly in younger school children. School-based interventions are also effective at reducing obesity if components to increase physical activity and reduce sedentary behaviors are also targeted but not if only dietary behaviors are tackled. Most of the high-quality evaluation studies using randomized controlled trials have been carried out in high-income countries as they are costly to run. However, middle-income countries have benefitted from the information available from these evaluation studies and many are now starting to fund and evaluate school-based programs themselves, resulting in unique problems such as concomitant under- and overnutrition being addressed. Action for the future demands more focus on populations most at risk of poor dietary quality and obesity in order to reduce inequalities in health and on adolescents who have not benefited as much as younger children from school-based interventions. This will involve innovative solutions within schools as well as targeting the food environment outside schools such as reducing the density of fast-food outlets and marketing of sweet and savory snacks and drinks.

Bariatric surgery in adolescents: what do we know so far?

Introduction:

Obesity represents a vast and rapidly increasing global burden. Bariatric surgery is the only intervention achieving sustained weight loss, among its wide-ranging benefits.

Methods:

In this article, we describe the growing challenges presented by adolescents with severe obesity and review the literature on surgical and other treatment options.

Results:

Outcomes in terms of weight loss, metabolic and quality of life improvement, reversal of obstructive sleep apnea, insulin resistance, type II diabetes mellitus, hypertension, and dyslipidemia appear comparable to those seen in adults. However, long-term data on safety and sustainability are lacking. There is a growing acceptance of the need for surgery as a treatment for the morbidly obese adolescent population, and the number of studies reporting outcomes after adolescent bariatric surgery is increasing.

Conclusion:

Accumulating evidence suggests that the benefits seen in adult bariatric surgery can be reproduced in adolescents. Thus, adolescent bariatric surgery appears to be safe and effective in achieving benefits desired in terms of weight control and improvements in metabolic health and quality of life. However, particular care must be taken when treating a young population, and long-term outcomes are awaited to properly define indications and limitations.