Family and Neighborhood Correlates of Overweight and Obesogenic Behaviors Among Chinese Children

A school-based food and nutrition education intervention increases nutrition-related knowledge and fruit consumption among primary school children in northern Ghana

BACKGROUND

Providing children with the opportunity to learn about nutrition is critical in helping them establish a healthy lifestyle and eating behaviours that would remain with them till adulthood. We determined the effect of a school-based food and nutrition education (SFNE) intervention on the nutrition-related knowledge, attitudes, dietary habits, physical activity levels and the anthropometric indices (BMI-for-age z scores, %Body fat and waist circumference) of school-age children in northern Ghana.

METHODS

Following a controlled before-and-after study design, we recruited school-age children in primary 4 and 5 from public and private schools and assigned them non-randomly to intervention and control groups (4 schools total). A SFNE intervention called 'Eat Healthy, Grow Healthy (EHGH)' was implemented in intervention schools. Components of the intervention included children, teachers, school officials, and the school environment. Nutrition education didactic sessions, active discussions, nutrition games, charades, art work, and physical activity sessions were among the teaching and learning activities implemented. At 0 and 6 months, primary (anthropometry) and secondary (fruit, vegetable, and breakfast consumption) outcomes were obtained.

RESULTS

Mean BMI-for-age z-scores did not differ significantly between intervention and control groups (F1,261 = 0.45, P = 0.503, η2 = 0.01). However, significantly greater nutrition-related knowledge scores were recorded in the intervention group than in the control group at post-intervention (M = 6.07 SD = 2.17 vs. M = 5.22 SD = 1.92; p = 0.002). Mean number of days intervention children consumed fruits differed across time (F1, 263 = 33.04, p = 0.002, η2 = 0.04) but not between the control and intervention groups (F1, 263 = 0.28, p = 0.60, η2 = 0.00).

CONCLUSIONS

The EHGH intervention had positive effects on the nutrition-related knowledge and the consumption of fruits among children although it did not impact their anthropometric indices.

Empowered mothers and co-resident grandmothers: Two fundamental roles of women impacting child health outcomes in Punjab, Pakistan

We show that i) empowered mothers and ii) coresident grandmothers each benefit children's nutritional health measured by height-for-age z-scores (HAZ) and weight-for-age z-scores (WAZ) for age groups 5 years and less. First, using cross-sectional data from the Pakistan Demographic and Health Survey (PDHS) for the year 2017-18, we estimate the impact of empowered mothers on child health outcomes using an instrumental variable approach to correct for endogeneity. Empowerment is measured by two indices: as a sum of the questions that gauge both attitudinal and behavioral dimensions of female agency and also and using multiple correspondence analysis (MCA) for these same questions. Second, we use a fuzzy regression discontinuity design (FRDD) to measure the causal impact of coresident grandmothers on the health outcomes of the children using multiple rounds of the Multiple Indicator Cluster Survey (MICS) from the years 2008, 2011, 2014 and 2018. The difference between the actual ages of the grandmother from the Potential Retirement Eligibility Criteria (PREC) has been used to correct for potential endogeneity. The results show that on average, the weight for age z-scores (WFA) for children under five increases by 0.28 SD with a one-index point increase in mother's empowerment. Similarly, on average, WFA increases by 0.098 SD when grandmothers are present in a household. Finally, we explore heterogeneity in the average effects stated above based upon the gender of the child as well as the wealth and geographic location of the household. The benefits of mothers' empowerment are largely driven by improvements in girls' nutrition as well as children living in rural areas while the presence of grandmothers primarily improves the nutrition of boys, children in rural areas, and children belonging to poor families.

Relationship between Live-In Grandparents and Grandchild's Health and Well-Being in Palestinian Refugees in Lebanon

Grandparents (GP) play influential roles in grandchildren's health, behavior, and life. However, this relationship has not been examined in the Arab region. This study assesses whether the presence of GP in the household is associated with grandchildren's health and wellbeing. Health status was determined by a child experiencing chronic health conditions or an acute illness, and wellbeing was determined based on school attendance and child labor. Data were collected through surveys conducted in 2010 and 2015 of representative samples of Palestinian refugees living in Lebanon. Multivariate logistic regression showed that, even after controlling for potential confounders, including the presence of parents in the household and household food insecurity (FI), the presence of live-in GP was associated with lower odds of children experiencing acute illnesses (OR 0.74 95% CI 0.62-0.92) and higher odds of attending school (OR 2.22 95% CI 1.28-5.33), but not child labor. The presence of GP in the household may be protective to grandchildren's health status and school attendance in this population.

Too Many Treats or Not Enough to Eat? The Impact of Caregiving Grandparents on Child Food Security and Nutrition

With the number of grandparent-headed households on the rise, the influence of grandparents needs to be considered in the fight to reduce child obesity. The current study investigated the influence of caregiver type (i.e., grandparents only, parents only, or multi-generational households) on children’s nutrition, food security, and BMI. This was a cross-sectional, secondary analysis based on the 2009–2010 wave of the Health Behavior in School-Aged Children (HBSC) survey in collaboration with the World Health Organization. This sample included 12,181 students from 10,837 families with only parents present in the household, 238 with only grandparents present, and 1106 multi-generational families. One-way analyses of covariance (ANCOVAs) were conducted using caregiver type as the independent variable, controlling for SES, on items assessing frequency of breakfast consumption, nutrition intake, hunger, snacking frequency and location, and BMI. Children reported more unhealthy snacking in households with only grandparents. Hunger was reported more often in multi-generational households. These results support that caregiver type, especially caregiving grandparents, is a significant predictor of children’s BMI, nutrition, and food security. Tailoring nutrition education to the needs of grandparents could help both the health of grandparents and the reduction of child obesity.

The association of grandparental co-residence and dietary knowledge with excess body weight among children aged 7-15 years in China

OBJECTIVES

To investigate the impact of grandparent's co-residence and dietary knowledge on the overweight and obesity risk among school-age children in China.

METHODS

Data of 790 children aged 7-15 years were retrieved from the China Health and Nutrition Survey (CHNS). Co-residential status was evaluated using household and individual ID. Dietary knowledge was assessed using 17 dietary statements, which was scored by participants. Three principal factors were extracted by factor analysis. Logistic regression analysis was applied to examine the influence of grandparent's co-residence and dietary knowledge on the weight status of the child.

RESULTS

The overweight and obesity incidence of the children increased significantly when they co-reside with two grandparents (OR=1.447, 95CI: 1.001-2.090, p=0.049). Mother's dietary knowledge regarding to protein-related food choices (PT) scored higher was associated with the increased risk (OR=1.270, 95CI: 1.059-1.523, p=0.010). For grandmother's dietary knowledge, the higher score in balanced food consumption (BF) was associated with the decreased overweight and obesity risk (OR=0.456, 95CI: 0.294-0.706, p<0.001). Grandfather's dietary knowledge in BF showed the similar result (OR=0.454, 95CI: 0.271-0.759, p=0.003).

CONCLUSIONS

Living with two grandparents is associated with higher overweight and obesity risk, but grandparents with an adequate knowledge in the balanced food consumption may decrease the risk.

School-based behaviour change intervention to increase physical activity levels among children: a feasibility cluster non-randomised controlled trial in Yangzhou, China

OBJECTIVES

Children in China have low levels of physical activity. We developed a school-based behaviour change intervention to increase their physical activity levels. The study aimed to determine the feasibility of undertaking a cluster randomised controlled trial (RCT) in the future. This future cluster RCT will evaluate the effectiveness of the intervention.

DESIGN

Feasibility cluster non-RCT design.

SETTING

Two public schools (one intervention and one control) in Yangzhou, China.

PARTICIPANTS

Children aged 10-12 years and their parents.

INTERVENTION

The 16-week school-based behaviour change intervention to increase physical activity levels consisted of three components (a) health education (physical education), (b) family involvement and (c) school environment support.

OUTCOMES MEASURES

We estimated important parameters that are needed to design the future cluster RCT, such as SD of the primary outcome (ie, 7-day steps in children), intracluster correlation coefficient (ICC), recruitment of child-parent dyads, follow-up of children, completion of and time needed for data collection among children and intervention attendance.

RESULTS

Sixty-four children and their parents participated in the study (32 per study group). The SD of the primary outcome was 34 519 steps. The ICC was 0.03. The recruitment and follow-up rates were 100%. The completion of data collection was 100% (except for the 7-day steps at baseline-one child lost the step log in the intervention group and two children lost their pedometer in the control group). The time needed to complete the self-reported questionnaire by children was around 15 min per study group, and the measurement of their anthropometric parameters took around 40 min per study group. The intervention attendance was 100%.

CONCLUSIONS

Based on the promising recruitment, follow-up, completion of and time needed for data collection and intervention attendance, it would be feasible to undertake the future cluster RCT in China.

TRIAL REGISTRATION NUMBER

ChiCTR1900026865.

Formative Development of a Technology-Based Physical Activity Intervention for Grandparents and Grandchildren

Physical inactivity is a major public health issue among older adults and children. This study presents preliminary results that will inform the development of a technology-based physical activity intervention for grandparents and grandchildren (ages 6-12 years old). The authors used an iterative user-centered design framework to gather quantitative data from grandparents (n = 35) and subsequently invited a subset of 12 of them to engage in qualitative interviews. Participants were 63.1 ± 9.8 years old, 80% female, 64% U.S.-born, 43% Hispanic, 66% single, and 40% <$15K income. The majority of grandparents reported mobile device proficiency, very close relationships with their grandchildren, and interest in participating in an intergenerational intervention. Four key themes related to family closeness, dynamics, routines, and technology informed intervention development. Next steps involved a pilot trial using Fitbits and a fully functioning technology-based prototype. Grandparents are uniquely positioned within their families to serve as agents of change in health-promoting interventions.

State-of-the-art of measures of the obesogenic environment for children

Various measures of the obesogenic environment have been proposed and used in childhood obesity research. The variety of measures poses methodological challenges to designing new research because methodological characteristics integral to developing the measures vary across studies. A systematic review has been conducted to examine the associations between different levels of obesogenic environmental measures (objective or perceived) and childhood obesity. The review includes all articles published in the Cochrane Library, PubMed, Web of Science and Scopus by 31 December 2018. A total of 339 associations in 101 studies have been identified from 18 countries, of which 78 are cross-sectional. Overall, null associations are predominant. Among studies with non-null associations, negative relationships between healthy food outlets in residential neighbourhoods and childhood obesity is found in seven studies; positive associations between unhealthy food outlets and childhood obesity are found in eight studies, whereas negative associations are found in three studies. Measures of recreational or physical activity facilities around the participants' home are also negatively correlated to childhood obesity in nine out of 15 studies. Results differ by the types of measurement, environmental indicators and geographic units used to characterize obesogenic environments in residential and school neighbourhoods. To improve the study quality and compare reported findings, a reporting standard for spatial epidemiological research should be adopted.

The relationship between the home environment and child adiposity: a systematic review

BACKGROUND

Extensive research has demonstrated the role of the Home Environment (HE) in shaping children's energy balance behaviours. Less is known about direct relationships with bodyweight. This review examines associations between the social and physical aspects of three pre-defined Home Environment domains (food, physical activity and media) and adiposity measures in children ≤12 years.

METHODS

Six electronic databases (PubMed, Medline, EBSCO CINAHL, EMBASE, Web of Science, PsycInfo) were systematically searched up to October 2020. Studies reporting at least one physical and/or social aspect of the food, physical activity and/or media domains of the Home Environment in relation to child adiposity outcomes were included (n = 62).

RESULTS

Most studies examined one (n = 41) or two domains (n = 16). Only five studies assessed all three domains of the Home Environment. Most consistent relationships were observed for physical aspects of the home media environment; with greater availability of electronic devices associated with higher child adiposity (21/29 studies). Findings were less consistent for the smaller number of studies examining physical aspects of the home food or physical activity environments. 8/15 studies examining physical food environments reported null associations with adiposity. Findings were similarly mixed for physical activity environments; with 4/7 reporting null associations, 2/7 reporting negative associations and 1/7 reporting positive associations between access to physical activity equipment/garden space and adiposity. Fewer studies assessed social aspects (e.g. caregiver modelling or limit setting) of the Home Environment in relation to child adiposity and findings were again mixed; 9/16 media environment, 7/11 food environment and 9/13 physical activity environment studies reported null associations with child adiposity outcomes.

CONCLUSIONS

The home media environment was most consistently associated with adiposity in childhood. Findings were less consistent for the home food and physical activity environments. Greater agreement on definitions and the measurement of the obesogenic home environment is required in order to clarify the strength and direction of relationships with child adiposity. Robust longitudinal research using comprehensive measures of the holistic home environment is needed to better identify which aspects contribute to excess weight gain in childhood.

TRIAL REGISTRATION

PROSPERO Systematic review registration number:  CRD42018115139 .

Influence of Grandparental Child Care on Childhood Obesity: A Systematic Review and Meta-Analysis

Objective: This study systematically reviewed the scientific literature on the relationship between grandparental child care and childhood obesity. Methods: Keyword/reference search was performed in CINAHL, PsycINFO, PubMed, and Web of Science. Meta-analysis was conducted to estimate the pooled effect of grandparental child care on children's weight outcomes. Results: A total of 23 studies were identified, including 9 longitudinal, 9 cross-sectional, 2 case-control, and 3 qualitative studies. Eight studies were conducted in China, five in Japan, three in the United Kingdom, two in the United States, and one in five other countries each. Twelve studies focused on grandparents' roles as a main caregiver in the family, and seven on grandparents' co-residence. Data from 14 studies were used in meta-analysis, 10 focusing on childhood overweight/obesity and the other 4 on children's BMI z-scores. Meta-analysis found that grandparental child care was associated with a 30% (95% confidence interval = 21-40) increase in childhood overweight/obesity risk. Grandparental child care was not associated with children's BMI z-scores after correcting for publication bias. Meta-regressions revealed no difference in the estimated effect of grandparental child care on children's weight outcomes by country or grandparents' specific roles (main caregiver in the family vs. co-residence). Conclusions: Preliminary evidence links grandparental child care to elevated risk of childhood overweight/obesity, but not BMI z-scores. Future research should focus on a specific child age group within a country, adopt systematic and field-validated measures on grandparental child care, and elucidate the pathways linking grandparental child care to children's weight outcomes.

Impact of neighbourhood food environment on diet and obesity in China: a systematic review

OBJECTIVE

This study systematically reviewed literature on the neighbourhood food environment in relation to diet and obesity among residents in China.

DESIGN

A keyword search of peer-reviewed articles was performed in Cochrane Library, PubMed, and Web of Science. Eligibility criteria include study designs: longitudinal/cohort studies or cross-sectional studies; study participants: people of all ages; exposures: neighbourhood food environment (e.g. restaurants, supermarkets, wet markets, fast-food restaurants, or convenience stores); outcomes: diet and/or body weight status; and country: China.

RESULTS

Seventeen studies met all criteria and were included. Among the eight studies that assessed the neighbourhood food environment in relation to diet, six reported at least one statistically significant relationship in the expected direction, whereas the remaining two exclusively reported null effects. Among the eleven studies that assessed the neighbourhood food environment in relation to body weight or overweight/obesity, ten reported a significant association whereas the remaining one reported a null relationship. Variety, density, and proximity of food outlets were positively associated with local residents' dietary diversity, portion size, and daily caloric intake. Density and proximity of fast-food restaurants and convenience stores were positively associated with local residents' adiposity in some but not all studies. Evidence linking any specific food outlet type to diet/obesity remains lacking due to the small number of studies and heterogeneities in food environment measures, geographical locations, and population subgroups.

CONCLUSIONS

The neighbourhood food environment may influence diet and obesity among Chinese residents but the evidence remains preliminary. Future studies adopting an experimental study design and objective/validated environment and dietary measures are warranted.

The CHIRPY DRAGON intervention in preventing obesity in Chinese primary-school--aged children: A cluster-randomised controlled trial

BACKGROUND

In countries undergoing rapid economic transition such as China, rates of increase in childhood obesity exceed that in the West. However, prevention trials in these countries are inadequate in both quantity and methodological quality. In high-income countries, recent reviews have demonstrated that school-based prevention interventions are moderately effective but have some methodological limitations. To address these issues, this study evaluated clinical- and cost- effectiveness of the Chinese Primary School Children Physical Activity and Dietary Behaviour Changes Intervention (CHIRPY DRAGON) developed using the United Kingdom Medical Research Council complex intervention framework to prevent obesity in Chinese primary-school-aged children.

METHODS AND FINDINGS

In this cluster-randomised controlled trial, we recruited 40 state-funded primary schools from urban districts of Guangzhou, China. A total of 1,641 year-one children with parent/guardian consent took part in baseline assessments prior to stratified randomisation of schools (intervention arm, 20 schools, n = 832, mean age = 6.15 years, 55.6% boys; control arm n = 809, mean age = 6.14 years, 53.3% boys). The 12-month intervention programme included 4 school- and family-based components delivered by 5 dedicated project staff. We promoted physical activity and healthy eating behaviours through educational and practical workshops, family activities, and supporting the school to improve physical activity and food provision. The primary outcome, assessed blind to allocation, was between-arm difference in body mass index (BMI) z score at completion of the intervention. A range of prespecified, secondary anthropometric, behavioural, and psychosocial outcomes were also measured. We estimated cost effectiveness based on quality-adjusted life years (QALYs), taking a public sector perspective. Attrition was low with 55 children lost to follow up (3.4%) and no school dropout. Implementation adherence was high. Using intention to treat analysis, the mean difference (MD) in BMI z scores (intervention - control) was -0.13 (-0.26 to 0.00, p = 0.048), with the effect being greater in girls (MD = -0.18, -0.32 to -0.05, p = 0.007, p for interaction = 0.015) and in children with overweight or obesity at baseline (MD = -0.49, -0.73 to -0.25, p < 0.001, p for interaction < 0.001). Significant beneficial intervention effects were also observed on consumption of fruit and vegetables, sugar-sweetened beverages and unhealthy snacks, screen-based sedentary behaviour, and physical activity in the intervention group. Cost effectiveness was estimated at £1,760 per QALY, with the probability of the intervention being cost effective compared with usual care being at least 95% at a willingness to pay threshold of £20,000 to 30,000 per QALY. There was no evidence of adverse effects or harms. The main limitations of this study were the use of dietary assessment tools not yet validated for Chinese children and the use of the UK value set to estimate QALYS.

CONCLUSIONS

This school- and family-based obesity prevention programme was effective and highly cost effective in reducing BMI z scores in primary-school-aged children in China. Future research should identify strategies to enhance beneficial effects among boys and investigate the transferability of the intervention to other provinces in China and countries that share the same language and cultures.

TRIAL REGISTRATION

ISRCTN Identifier ISRCTN11867516.

How do grandparents influence child health and development? A systematic review

Grandparents are often a key source of care provision for their grandchildren, yet they are sidelined in caregiving research and policy decisions. We conducted a global, systematic review of the literature to examine the scope and quality of studies to date (PROSPERO database CRD42019133894). We screened 12,699 abstracts across 7 databases, and identified 206 studies that examined how grandparents influence child health and development. Indicators of grandparent involvement were contact, caregiving behaviors, and financial support. Our review focused on two research questions: how do grandparents influence child health and development outcomes, and what range of child outcomes is reported globally? We examined study design, sample characteristics, key findings, and outcomes pertaining to grandchildren's physical health, socio-emotional and behavioral health, and cognitive and educational development.  Our search captured studies featuring grandparent custodial care (n = 35), multigenerational care (n = 154), and both types of care (n = 17). We found substantial heterogeneity in the data provided on co-residence, caregiving roles, resources invested, outcomes, and mechanisms through which "grandparent effects" are manifested. We identified two important issues, related to operationalizing indicators of grandparent involvement and conceptualizing potential mechanisms, leading to gaps in the evidence base. Currently, our understanding of the pathways through which grandparents exert their influence is constrained by limited data on what grandparents actually do and insufficient attention given to interpersonal and structural contexts. We present a conceptual framework to explicitly measure and theorize pathways of care, with a view to inform research design and policy implementation. We underscore the need for more robust data on three indicators of caregiver involvement-contact, behavior, and support-and for careful description of structural and interpersonal contexts in caregiving research.

Impact of built environment on physical activity and obesity among children and adolescents in China: A narrative systematic review

BACKGROUND

Neighborhood built environment may profoundly influence children's physical activity (PA) and body weight. This study systematically reviewed scientific evidence regarding the impact of built environment on PA and obesity among children and adolescents in China.

METHODS

A keyword and reference search was conducted in Active Living Research, Cochrane Library, PubMed, and Web of Science. Studies that met all of the following criteria were included in the review: (1) study designs-experimental studies, observational studies, and qualitative studies; (2) study subjects-Chinese children and/or adolescents aged ≤17 years; (3) exposures-neighborhood built environment; (4) outcomes-PA and/or body weight status; (5) article type-peer-reviewed publications; (6) time window of search-from the inception of an electronicbibliographic database to May 31, 2018; (7) country-China; and (8) language-articles written in English.

RESULTS

A total of 20 studies, including 16 cross-sectional studies, 3 longitudinal studies, and 1 descriptive study, met the predetermined selection criteria and were included in the review. A total of 13 studies adopted subjective built environment measures reported by parents and/or children,2 adopted objective measures (e.g., geographical information system, field observations), and 5 adopted both objective and subjective measures. PA behaviors included PA, physical inactivity, sedentary behavior, active/passive commuting from/to school, and park visits. Among the 16 studies that provided some quantitative estimates of the influence of built environment on PA and body weight status, all reported a statistically significant relationship in the expected direction. Availability and accessibility in proximity to greenspaces, parks, recreational facilities, and sidewalks were found to be associated with increased PA levels, reduced sedentary behaviors, and/or active commuting among Chinese childrenand adolescents. In contrast, the absence of bike lanes and living in higher density residential areas were associated with increased likelihood of childhood overweight and obesity.

CONCLUSION

Neighborhood built environment plays an important role in Chinese children's PA engagement and weight outcomes. Building new exercise facilities and enhancing the accessibility of existing facilities hold the potential to enhance PA engagement among Chinese children and adolescents. In addition, urban designs that incorporate sidewalks, bike lanes, walking paths, less motorized traffic, and lower residential density are likely to promote PA and prevent childhood obesity in China.

Links between the organization of the family home environment and child obesity: a systematic review

Due to increasingly high rates of child overweight and obesity, it is important to identify risk and protective factors that may inform more effective prevention and intervention. The degree of organization in the family home environment is a studied, but not well-specified, factor that may impact child weight. Prior research on household organization has examined an array of constructs, including family routines, limit setting, household chaos, crowding and the broad home environment. This study systematically reviews literature on organization within the family home environment and weight among children ages 2-12. Six hundred thirty-seven studies were reviewed by four coders for eligibility, and 32 studies were included in the final synthesis. Overall, 84% of studies provided evidence for relations between at least one indicator of organization within the family home environment and child weight. Studies provided compelling evidence across several constructs, suggesting that the relevance of household organization to child weight extends beyond a single indicator. Directions for future work include (i) examining the mediating role of health behaviours, (ii) examining the moderating role of socioeconomic factors, (iii) broadening this evidence base across cultures and nationalities and (iv) integrating constructs to develop a comprehensive model of organization within the home environment.

Cluster-randomised controlled trial to assess the effectiveness and cost-effectiveness of an obesity prevention programme for Chinese primary school-aged children: the CHIRPY DRAGON study protocol

INTRODUCTION

Childhood obesity in China has increased more rapidly and over a shorter time period than in other countries. However, there is a paucity of rigorously developed and evaluated prevention interventions. We aim to evaluate the clinical and cost-effectiveness as well as the implementation process of a complex multicomponent intervention developed using the UK Medical Research Council (MRC) framework. This study provides one of the first examples of rigorous development and evaluation of a childhood obesity prevention programme in a non-western population using the MRC methods.

METHODS AND ANALYSIS

A cluster-randomised controlled trial in 40 primary schools in Guangzhou, China, including children aged 6-7 years at baseline. Schools will be randomly allocated to either the usual practice (n=20) or intervention arm (n=20). The 12-month intervention consists of four components targeting diet and physical activity behaviours in and outside school, with family involvement. The primary objective is to compare the difference in mean body mass index (BMI) z-score between the intervention and control arms at the end of the intervention (starting March/April 2017). A sample size of 1640 pupils recruited from 40 schools is sufficient to detect a difference of 0.17 units in the mean BMI z-score with a power of 80% (ICC=0.01. ICC, intraclass correlation coefficient) and a significance level of 5%. Treatment effects will be tested using a mixed linear model in STATA adjusting for the child baseline BMI z-score and clustering by school. All analyses will be by intention to treat. Secondary analyses will additionally adjust for prespecified school-level and child-level covariates. The incremental cost-effectiveness ratio for the intervention versus usual practice will be 'cost per quality-adjusted life year (QALY)'. Cost per change in BMI z-score will also be assessed. A range of methods will be used to evaluate intervention implementation, mechanisms of impact and contextual factors.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the Life and Health Sciences Ethical Review Committee at the University of Birmingham and the Ethical Committee of Guangzhou Centre for Disease Control and Prevention. The primary, secondary, process evaluation and economic evaluation results of the trial will be disseminated through relevant international peer-reviewed journals and conferences.

TRIAL REGISTRATION NUMBER

ISRCTN11867516; Pre-results.

A systematic review of grandparents' influence on grandchildren's cancer risk factors

Many lifestyle patterns are established when children are young. Research has focused on the potential role of parents as a risk factor for non communicable disease in children, but there is limited investigation of the role of other caregivers, such as grandparents. The aim of this review was to identify and synthesise evidence for any influence grandparents' care practices may have on their grandchildren's long term cancer risk factors. A systematic review was carried out with searches across four databases (MEDLINE, Embase, Web of Science, PsycINFO) as well as searches of reference lists and citing articles, and Google Scholar. Search terms were based on six areas of risk that family care could potentially influence-weight, diet, physical activity, tobacco, alcohol and sun exposure. All study designs were included, as were studies that provided an indication of the interaction of grandparents with their grandchildren. Studies were excluded if grandparents were primary caregivers and if children had serious health conditions. Study quality was assessed using National Institute for Health and Care Excellence checklists. Grandparent impact was categorised as beneficial, adverse, mixed or as having no impact. Due to study heterogeneity a meta-analysis was not possible. Qualitative studies underwent a thematic synthesis of their results. Results from all included studies indicated that there was a sufficient evidence base for weight, diet, physical activity and tobacco studies to draw conclusions about grandparents' influence. One study examined alcohol and no studies examined sun exposure. Evidence indicated that, overall, grandparents had an adverse impact on their grandchildren's cancer risk factors. The theoretical work in the included studies was limited. Theoretically underpinned interventions designed to reduce these risk factors must consider grandparents' role, as well as parents', and be evaluated robustly to inform the evidence base further.

A scoping review of epidemiologic risk factors for pediatric obesity: Implications for future childhood obesity and dental caries prevention research

RESEARCH QUESTIONS

What are the non-modifiable (socioeconomic, genetic) and modifiable factors (physical activity, dietary behaviors) related to childhood (under age 12) obesity? How can this knowledge be applied to oral health professionals' efforts to prevent or manage dental caries in children?

OBJECTIVES

Studies have identified risk factors for childhood obesity. The purpose of this scoping review was to develop a conceptual model to identify non-modifiable and modifiable risk factors for childhood obesity and to illustrate how these findings are relevant in developing interventions aimed at preventing obesity and dental caries in children.

METHODS

The authors searched PubMed and Embase and limited the study to English-language publications. A total of 2,572 studies were identified. After de-duplication, 2,479 studies remained and were downloaded into a citation-management tool. Two authors screened the titles and abstracts for relevance. Two hundred and sixty studies remained and were retrieved for a full-text review, and 80 studies were excluded, resulting in 180 studies included in the scoping review. An inductive content analytic methods was used to organize all statistically significant obesity risk factors into seven domains, which were classified as non-modifiable or modifiable; then a conceptual model of common risk factors associated with childhood obesity and dental caries was developed.

RESULTS

Non-modifiable obesity risk factors include biological and developmental (e.g., genes, developmental conditions, puberty), sociodemographic and household (e.g., race/ethnicity, socioeconomic status, parent education, unemployment), cultural (e.g., degree of acculturation), and community (e.g., neighborhood composition). Modifiable risk factors included behavioral (e.g., diet, physical activity, weight), psychosocial (e.g., maternal stress, family functioning, parenting practices, child temperament), and medical (e.g., parent smoking, maternal health, child health).

CONCLUSIONS

Identifying common risk factors has important implications for future oral health research aimed at preventing childhood obesity and dental caries. Epidemiologic knowledge gleaned from the literature can be used to develop rigorous interventions and programs aimed at preventing these highly prevalent diseases and improving health outcomes for children.

Differences in perceived causes of childhood obesity between migrant and local communities in China: A qualitative study

In developing countries, obesity traditionally affectsmore affluent children, butis spreading to a wider social group. Understanding the perceivedcontributors can provide valuable insights to plan preventive interventions. We exploreddifferences in the perceived causes of childhood obesity between local and migrant communities in a major Chinese city. We conducted 20 focus groups (137 parents, grandparents, school teachers) and 11semi-structured interviews with school Principals from migrant and local communities in Guangzhou. Data were transcribed and analysed using a thematic approach. We found that Lack of influence from grandparents, who were perceived to promote obesogenic behaviorin local children, fewer opportunities for unhealthy snacking and less pressure for academic attainment leading to moreactive play were interpreted as potential "protective" factors among migrant children. Nevertheless, two perceived causes of obesity were more pronounced in migrant than local children: lack of parental monitoring after-school andunsafe neighborhoods limiting physical-activity. Two barriers that restricted child physical activity were only found in the migrant community: limited home space, and cultural differences, inhabitinginteractive play with local children. Future interventions should consider uniquedeterminants of obesity in children from different social backgrounds, with tailored strategies to prevent further rise of the epidemic.

Factors of physical activity among Chinese children and adolescents: a systematic review

Background

Lack of physical activity is a growing problem in China, due to the fast economic development and changing living environment over the past two decades. The aim of this review is to summarize the factors related to physical activity in Chinese children and adolescents during this distinct period of development.

Methods

A systematic search was finished on Jan 10^th, 2017, and identified 2200 hits through PubMed and Web of Science. English-language published studies were included if they reported statistical associations between factors and physical activity. Adapted criteria from the Strengthening The Reporting of OBservational studies in Epidemiology (STROBE) statement and evaluation of the quality of prognosis studies in systematic reviews (QUIPS) were used to assess the risk of bias of the included studies. Related factors that were reported in at least three studies were summarized separately for children and adolescents using a semi-quantitative method.

Results

Forty two papers (published 2002–2016) were included. Most designs were cross-sectional (79%), and most studies used questionnaires to assess physical activity. Sample size was above 1000 in 18 papers (43%). Thirty seven studies (88%) showed acceptable quality by methodological quality assessment. Most studies reported a low level of physical activity. Boys were consistently more active than girls, the parental physical activity was positively associated with children and adolescents’ physical activity, children in suburban/rural regions showed less activity than in urban regions, and, specifically in adolescents, self-efficacy was positively associated with physical activity. Family socioeconomic status and parental education were not associated with physical activity in children and adolescents.

Conclusions

The studies included in this review were large but mostly of low quality in terms of study design (cross-sectional) and methods (questionnaires). Parental physical activity and self-efficacy are promising targets for future physical activity promotion programmes. The low level of physical activity raises concern, especially in suburban/rural regions. Future research is required to enhance our understanding of other influences, such as the physical environment, especially in early childhood.

Electronic supplementary material

The online version of this article (doi:10.1186/s12966-017-0486-y) contains supplementary material, which is available to authorized users.

Relationship between the home environment and fruit and vegetable consumption in children aged 6-12 years: a systematic review

OBJECTIVE

As numerous factors in the home environment have been related to children's fruit and vegetable (F&V) consumption as a component of a healthy diet, the purpose of the present systematic review was to examine these factors specifically for children aged 6-12 years.

DESIGN

Relevant observational studies published in English between January 2007 and December 2015 were obtained through electronic database searches. Studies were included if the researchers reported on a potentially modifiable measure of the home physical, political and sociocultural environment related to child F&V consumption.

RESULTS

Of the thirty-three articles reviewed, overall methodological quality was poor with twenty studies rated as weak, mainly due to cross-sectional design (majority of studies), selection bias, convenience sampling and voluntary participation. Half of the studies had strong-moderate ratings for using valid and/or reliable tools while for the other half, psychometric properties were either not reported or weak. The most consistent evidence for children's combined F&V consumption was found for availability and accessibility of F&V, parental role modelling of F&V and maternal intake of F&V.

CONCLUSIONS

A vast array of home environment components and their influence on children's consumption of fruits and/or vegetables have been studied in recent years. Specific components of the home environment may have more influence than others, but more compelling evidence is needed to draw strong conclusions. Recommendations are made for future studies to be based upon conceptual/theoretical models to provide consistency in defining the home environment and investigation of potential moderators, such as personal or contextual factors.

Socioeconomic determinants of childhood obesity among primary school children in Guangzhou, China

Background

Socioeconomic inequalities in childhood obesity prevalence differ according to a country’s stage of nutrition transition. The aim of this study was to determine which socioeconomic factors influence inequalities in obesity prevalence in Chinese primary school children living in an urban setting.

Methods

We assessed obesity prevalence among 9917 children aged 5–12 years from a stratified random sample of 29 state-funded (residents) and private (migrants) schools in Guangzhou, China. Height and weight were objectively measured using standardised methods and overweight (+1 SD < BMI-for-age z-score ≤ +2 SD) and obesity (BMI-for-age z-score > +2 SD) were defined using the World Health Organisation reference 2007. Socioeconomic characteristics were ascertained through parental questionnaires. Generalised Linear Mixed Models with schools as a random effect were used to compare likelihood of overweight/obesity among children in private, with public schools, adjusting for child age and sex, maternal and paternal BMI and education level, and household per-capita income.

Results

The prevalence of overweight/obesity was 20.0 % (95 % CI 19.1 %–20.9 %) in resident compared with 14.3 % (95 % CI 13.0 %–15.4 %) in migrant children. In the adjusted model, the odds of overweight/obesity remained higher among resident children (OR 1.36; 1.16–1.59), was higher in boys compared with girls (OR 2.56; 2.24–2.93), and increased with increasing age (OR 2.78; 1.95–3.97 in 11–12 vs 5–6 year olds), per-capita household income (OR 1.27; 1.01–1.59 in highest vs lowest quartile) and maternal education (OR 1.51; 1.16–1.97 in highest vs lowest). Socioeconomic differences were most marked in older boys, and were only statistically significant in resident children.

Conclusions

The socioeconomic gradient for childhood obesity in China is the reverse of the patterns seen in countries at more advanced stages of the obesity epidemic. This presents an opportunity to intervene and prevent the onset of social inequalities that are likely to ensue with further economic development. The marked gender inequality in obesity needs further exploration.

Built environmental correlates of physical activity in China: A review

Objective

China faces growing levels of physical inactivity and obesity, associated with increasing urbanization and changing lifestyles in recent years. China is expanding its cities to accommodate a growing urban population. This paper identifies built environment factors that are associated with physical activity in China. Findings can inform urban design and development in China to support increased physical activity.

Methods

This paper is modeled on a review of built environment correlates of walking by Saelens and Handy (2008). Saelens and Handy reviewed research in developed countries. The present paper reviews 42 empirical studies that were conducted in China and were published between 2006 and 2014.

Results

Results discuss the association of built environment features and physical activity for transportation, recreation and work. Studies focus on adults and on major cities. Data on the built environment is typically self-reported. Strongest evidence was found for the positive association of physical activity with proximal non-residential locations, pedestrian infrastructure, aesthetics, and non-park physical activity facilities, and for the negative association of physical activity with urban residence. In terms of physical activity for transportation, evidence is strongest for associations between physical activity for transportation and proximal non-residential locations.

Conclusion

More research is needed on the built environment and physical activity, especially including research on significant features of Chinese cities, such as air pollution, high density levels, traffic safety, and others. Research on associations between built environment features and physical activity should consider the specific social and built environment contexts of Chinese cities.

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Research on the environment and physical activity is increasing in China.

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Physical activity is linked to mixed land use, sidewalks, aesthetics, and facilities.

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Future research should address environments and issues specific to China.

Family-related risk factors of obesity among preschool children: results from a series of national epidemiological surveys in China

Background

Family-based child obesity prevention and control strategy has not yet established in many countries or regions, including China, thus what it needs to do now is to continuously develop and improve the strategies. The purpose of this study were to describe a wider spectrum of risk factors of obesity among preschool children and add to the mounting evidence for further improving suggested intervention measures in future family-based programs.

Methods

Data was collected as part of a series of national epidemiological surveys in childhood conducted in 9 Chinese cities. A population-based, 1:1 matched case–control design was employed to examine risk factors of obesity by means of conditional logistic regression. Obesity was defined as the International Obesity Task Force (IOTF) BMI-for-age cut offs. Eligible subjects were 1234 boys and 610 girls aged 3–7 years in 1996 and 2290 boys and 1008 girls in 2006, including obese and non-obese.

Results

High birth weight, gestational hypertension and parents’ BMI were closely associated with childhood obesity. Breast feeding in the first 4 months was a protective factor in univariate model in 2006 (OR = 0.834, P = 0.0234), but the association was not seen in multivariate. Appetite, eating speed, daily time and intensity for outdoor activities, night sleep time, and time for TV viewing were identified statistically by multivariate model. Those children brought up in extended family or mainly raised by their grandparents or lived in high income or low education families might have an increased risk of becoming obese. Parents’ attitudes on weight control of their children significantly differed between obese and non-obese groups.

Discussion

A wider spectrum of risk factors and an empirical aggregation of family-related risk factors are discussed to further improve future family-based child obesity prevention and control strategies. Most of the risk factors identified by this study presented ranked or quantitative characteristics which might be transformed from unhealthy threshold to healthy range by behavior modification. Some variables are likely to interact each other, such as appetite and eating speed, or outdoor activity and TV viewing, or BMI and income, but which needs to be further explored in future surveys.

Conclusions

The family-related risk factors were summarized from our identified risk factors of obesity among preschool children which strongly supported the further development of family-based programs in preschool period.

Factors influencing obesogenic dietary intake in young children (0-6 years): systematic review of qualitative evidence

BACKGROUND

Obesogenic dietary intake is prevalent in young children and is associated with obesity and other adverse health outcomes in childhood and later in life.

OBJECTIVE

To describe the barriers to and facilitators of obesogenic dietary intake in early childhood, in order to inform interventions and public health policies to prevent obesity.

DESIGN

Systematic review of qualitative literature on factors influencing obesogenic diets in children aged 0-6 years.

DATA SOURCES

MEDLINE, EMBASE, CINAHL, PsycINFO, Web of Knowledge, British Nursing Index, ASSIA and Sociological Abstracts.

REVIEW METHODS

Qualitative studies meeting the inclusion criteria were synthesised. Data were analysed by creating a thematic framework, underpinned by the socioecological model, which included familiarisation of data across the studies, indexing, charting, mapping and interpretation.

RESULTS

20 studies from the USA (10), Europe (6) and Australia (4) included the views of 1067 participants (901 parents/caregivers, 37 children, 87 teachers, 15 dieticians and 27 nursery staff). Study designs included focus groups (n=16), individual interviews (n=6) and ethnography (n=1) with some studies using more than one design. Despite wide differences in the study context and focus, several consistent themes emerged. Parental factors increasing young children's obesogenic diets were: negative parent/family/peer modelling, lack of knowledge, time constraints, using food as reward, affordability and concerns about child's health. Child preferences also increased intake. Environmental factors increasing intake include: availability, advertising, societal, cultural and preschool/childcare influences.

CONCLUSIONS

Future intervention strategies should aim to promote modelling of positive behaviours, create home and preschool environments that promote healthy diets, and simultaneously target factors at the family and preschool/childcare levels.

TRIAL REGISTRATION NUMBER

This review is one of a series of systematic reviews on the determinants of obesogenic behaviours in young children, registered with the International Prospective Register for Systematic Reviews (PROSPERO), CRD42012002881.

Impact of Caregiver Type for 3-Year-Old Children on Subsequent Between-Meal Eating Habits and Being Overweight From Childhood to Adulthood: A 20-Year Follow-up of the Ibaraki Children's Cohort (IBACHIL) Study

Background

Because of the increasing number of mothers who continue to work after childbirth, participation in childcare has diversified. However, the impact of the main caregiver on children’s habits has not been determined. We sought to examine the effect of caregiver differences on childhood habituation of between-meal eating and body mass index (BMI).

Methods

The Ibaraki Children’s Cohort Study involved 4592 Japanese children whose parents answered health questionnaires at age 3. Follow-up questionnaires were distributed to parents when children were 6 and 12 years old and to study subjects directly when they were 22 years old. We compared prevalence of between-meal eating and overweight as well as mean BMI at ages 6, 12, and 22 years, by their main daytime caregiver at age 3.

Results

Compared to children cared for by mothers, those cared for by grandparents had a higher prevalence of between-meal eating before dinner for boys and girls at ages 6 and 12 years. At age 22 years, boys cared for by grandparents had a higher prevalence of overweight than those cared for by mothers (18.5% versus 11.2%, P = 0.037), but no such difference was noted in girls. However, both boys and girls cared for by grandparents had higher mean BMI over time than those cared for by mothers (coefficient = 0.47 kg/m² for boys and coefficient = 0.35 kg/m² for girls).

Conclusions

Being cared for by grandparents at age 3 was associated with subsequent between-meal eating habits, being overweight, and increased mean BMI from childhood to adulthood.

The role of grandparents in childhood obesity in China - evidence from a mixed methods study

BACKGROUND

The current literature on the influences of family environment on childhood obesity is predominantly based on western populations and has focused on the role of parents. This study examined the influence of grandparents on the development of obesity among Chinese primary school aged children.

METHODS

A mixed methods study was conducted in four socioeconomically distinct primary school communities in two cities of southern China. The qualitative study (17 focus groups and four personal interviews) involved parents, grandparents, school staff, and food retailers in the vicinity of the schools (n = 99) and explored perceived causes of childhood obesity. The cross-sectional study examined the association between children's objectively measured weight status and reported health behaviours, and the presence and role of grandparents in the household. It included children from three randomly selected third grade (8 to 10 years) classes from each school (n = 497).

RESULTS

Grandparents were commonly perceived to contribute to childhood obesity through inappropriate perception (e.g. fat children are healthy and well cared for), knowledge (e.g. obesity related diseases can only happen in adults; the higher the dietary energy/fat content, the more nutritious the food), and behaviour (e.g. overfeeding and indulging through excusing the children from household chores). Conflicting child care beliefs and practices between grandparents and parents, and between grandparents and school teachers, were felt to undermine efforts to promote healthy behaviours in children. In the cross-sectional study, children who were mainly cared for by their grandparents were more likely to be overweight/obese (adjusted OR = 2.03; 95 % CI = 1.19 to 3.47); and to consume more sugar-added drinks and unhealthy snacks (B = 2.13, 95 % CI = 0.87 to 3.40), than children who were mainly cared for by their parents or other adult. Children who lived with two or more grandparents in the household were more likely to be overweight/obese than children who did not live with any grandparent (adjusted OR = 1.72; 95 % CI = 1.00 to 2.94).

CONCLUSIONS

Involvement of grandparents in childcare is an important factor contributing to childhood obesity in China. Future preventive interventions should include strategies that target grandparents.