Effectiveness of parent-centred interventions for the prevention and treatment of childhood overweight and obesity in community settings: A Systematic Review.

Abstract

Centre Conducting Review The Australian Centre for Evidence Based Nutrition and Dietetics (ACEBAND), School of Health Sciences, Faculty of Health, The University of Newcastle, New South Wales, Australia; a collaborating centre of the Joanna Briggs Institute. Review Question/ Objective The objective of this review is to identify the effectiveness of parent-centred interventions implemented in the community setting, in modifying eating and physical activity behaviours or weight-related outcomes of children. Background In Australia, 67% of men and 52% of women are considered to be overweight or obese 1. This is an enormous health concern, as being overweight or obese can lead to a range of chronic diseases such as heart disease, Type 2 diabetes, osteoarthritis, kidney and gall bladder disease, musculoskeletal and respiratory problems 1. This in turn may lead to a reduced quality of life and also places a large financial burden on governments for health care 2. Obesity is now seen as a major epidemic and is common in all age groups of all population groups in all parts of Australia 2. Obesity in childhood is an independent risk factor for adult obesity 3. The NSW Schools Physical Activity and Nutrition Survey 2004 found overall, a quarter of all boys and girls, and up to one third of year six boys, were overweight or obese 4. The prevalence of obesity in children and adolescents has increased markedly in all age groups and for both boys and girls in the past few decades 5. Overweight and obesity in childhood can adversely impact on both physical and psychological health. The occurrence of hyperlipideamia, hypertension, impaired glucose tolerance and insulin resistance in obese children and adolescents is increasing 6. Medical conditions such as sleep apnea, cholelithiasis, asthma and poor pulmonary function, hepatic steatosis and precocious puberty are all associated with childhood obesity 7. The rise in the prevalence of childhood obesity is a complex issue but widely recognised contributors include increased energy intake, decreased levels of physical activity and greater time spent in sedentary pursuits 8. A large number of environmental and cultural factors have also been identified as contributing to the problem 8. Obesity develops over time and once established, it is difficult to treat. Halting the epidemic ultimately will require not only a range of obesity treatment strategies but also effective prevention initiatives 9. Evidence to support an optimal approach to treating childhood obesity is limited with many studies showing only modest results at best in the long-term 10. However, the importance of family-based treatment that combines diet, physical activity and behavioural components has been acknowledged in a recent Cochrane Systematic Review 9. Parental involvement in obesity treatment interventions has been shown to be a important feature of the behavioural programs, particularly for children who are pre-adolescent 9. Efficacy trials in family-focussed nutrition and physical activity interventions for overweight and obese children have shown a reduction in BMI Zscores over a 2 year follow up 11. It has also been suggested that interventions offered in the community setting may help overcome barriers to participation, by making programs more accessible and allowing the targeting of specific sub-groups of the population 9. The prevention of weight gain, beginning in childhood, offers the most rational, and likely effective, means of achieving healthy weight in the population 2. Many interventions for the prevention of childhood obesity have been implemented into the school setting 9 with modest effects demonstrated in environmental and behavioural factors and also many health outcomes 8, 12 however a meta analysis of physical activity interventions on body mass index in children has shown no consistent positive changes in body composition 13. As children spend less than 50% of their awake time within school hours, studies are needed to address all of the daily influences on energy balance and improve living environments that support both healthy eating and physical activity outside of school hours 14. This includes the afterschool setting where many children spend their time in after-school care and activities. Beets et al has shown an after-school physical activity program can improve physical activity and fitness levels and other health related outcomes in children and adolescents 15. Economos et al 14 has shown an intervention implemented in before-, during, after-school and home settings decreased BMI Zscores in primary school aged children attending grades one to three, considered at high risk due to socioeconomic status and ethnicity 16. Interventions targeting families in population subgroups most at risk is a midstream behavioural approach to the childhood obesity problem. For children who are overweight, the risk of being overweight as adults is greater compared to children of healthy weight 3. Guo and Chumlea have reported children in the obese range (BMI >95th percentile) greater than 9 years of age have an 80% chance of having a BMI >28 at age 35 17. In addition, there is an increased risk for a child becoming overweight or obese if one parent is overweight and this risk is increased further if both parents are overweight 17. Overweight and obesity prevalence among children exists in a socioeconomic gradient with the most disadvantage quintiles more likely to have higher body mass index levels compared to those in the highest quintiles in developed nations such as Australia 18. Therefore, targeting families at community schools in a socioeconomically disadvantaged area aims to help those children who are the greatest risk for adverse weight-related health outcomes. Developing community based programs is part of what has been described as Community Based Participatory Research (CBPR) 19 and this is a framework that obesity researchers can apply in designing intervention programs in order to gain a better understanding of the social context in which obesity occurs. It involves community partners and consultation and so implementing the research is part of the research process itself 19. In order to improve the reach and evaluate the effectiveness of overweight and obesity prevention programs, they must be implemented in the community outside the controlled conditions of clinics and universities. In addition, they must be sustainable and evolve within the community in order to satisfy its needs. Criteria for inclusion Types of Participants This review will consider studies that include children of pre-school, primary and secondary school age and/or their parents aged >18 years. Types of interventions Interventions of interest are implemented in a community setting including, but not limited to; pre-schools (outside of curriculum), schools (non-curricular, before- and after-school), home based community centres and community camps, with an aim of improving eating and physical activity behaviours and/ or overweight/obesity outcome measures. Interventions conducted at pre-schools and schools must be conducted outside of those school curriculums and must be resourced separately. Types of Outcomes This review will consider studies that include the following outcome measures for children and / or their parents: i) Overweight/obesity related outcomes: weight (kg), % body weight lost, BMI, waist circumference (cm) ii) Eating behaviour outcomes: fruit and vegetable intake, macronutrient composition (eg fat intake per day), core food groups, diet quality iii) Physical activity behaviour outcomes: steps per day, time spent in activity, energy expenditure iv) Sedentary behaviour outcomes and constructs: Time spent in non-educational, small screen recreation (eg TV, computer, hand held electronic games.) Types of studies All intervention studies will be included in the review including: randomised controlled trials (RCTs); non-randomised controlled trials, longitudinal studies, cohort (both retrospective and prospective), case control and time series studies which have been conducted in a community setting. This will be used to evaluate effectiveness of the interventions in modifying nutrition or diet and physical activity behaviours of children. Search strategy This review will consist of a search of published and unpublished literature in the English language from 1975 to May 2009. The 1975 cut-off point was selected; as childhood obesity prevalence increased dramatically after the late 1970s therefore it is unlikely to find relevant studies targeting childhood obesity prevention and treatment prior to this date. A three-step search strategy will be utilised undertaking this review. An initial limited search of MEDLINE and CINAHL will be undertaken followed by analysis of the text words contained in the title and abstract, and of the index terms used to describe the article. A second search using all identified keywords and index terms will then be undertaken across all included databases. Thirdly, the reference list of all identified reports and articles will be searched for additional studies. Electronic databases to be searched; The Cochrane Library, MEDLINE/PREMEDLINE, EMBASE (Excerpta Medica Database, CINAHL (Cummalative index to Nursing and Allied Health Literature), Web of Science, Scopus and PsycINFO. The search for unpublished studies included Australian Digital Theses Program, and Dissertation Abstracts. Initial keywords to be used will be weight loss, overweight, obesity, prevention, treatment, management, community, after-school, intervention, family, parent, paediatric, healthy eating, diet, nutrition, physical activity, exercise. All studies identified during the database search will be assessed for relevance to review based on the information contained in the title, abstract and description/MESH heading by two independent reviewers. If the reviewers are uncertain of a study inclusion, a third reviewer will be consulted until consensus is reached. For all studies that appear to meet inclusion criteria the full article will be retrieved. If it is unclear from the title, abstract and description/MESH heading whether the study meets inclusion criteria the full article will be retrieved for clarification. A detailed report will be provided for all studies which meet the inclusion criteria. Assessment of methodological quality All papers selected for retrieval will be assessed independently by two reviewers for methodological quality prior to inclusion in the review using standardised critical appraisal instruments from the Joanna Briggs Institute Meta Analysis of Statistics Assessment and Review Instruments (JBI-MAStARI, Appendices I and II). If there is not agreement, a third reviewer will be consulted to resolve any disagreements. Due to low number of expected included studies, no studies will be excluded based on methodological quality. However the quality will be taken into consideration when determining whether meta-analysis is appropriate and in reporting outcomes and drawing conclusions. Data Collection Data will be extracted by two reviewers independently from papers included in this review using a modified version of the data extraction tool from JBI-MAStARI (Appendix III). This is to extract relevant data we are interested in not included in the standard tool. If any disagreement occurs between reviewers a third reviewer will be consulted. The data extracted will include specific details about: The intervention; description of its focus and components, Populations: number of participants, gender, age, retention. Setting: after school, home base, community centres. Study methods: study design, method of randomisation, length of intervention, data collection points, inclusion criteria Outcomes of significance to the review question and specific objectives: overweight/obesity, dietary behaviours, physical activity behaviours, Attendance. Data Synthesis Quantitative papers will, where possible, be pooled in statistical meta-analysis using the JBI-MAStARI. All results will be subject to double data entry. Odds ratio (for categorical data) and weighted mean differences (for continuous data) and their 95% confidence intervals will be calculated for analysis. Heterogeneity will be assessed using the standard Chi-square. Where statistical pooling is not possible the findings will be presented in narrative form. Conflict of interest None declared