Large reductions in child overweight and obesity in intervention and comparison communities 3 years after a community project.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: Childhood obesity has been increasing over decades and scalable, population-wide solutions are urgently needed to reverse this trend. Evidence is emerging that community-based approaches can reduce unhealthy weight gain in children. In some countries, such as Australia, the prevalence of childhood obesity appears to be flattening, suggesting that some population-wide changes may be underway. WHAT THIS STUDY ADDS: A community-based intervention project for obesity prevention in a rural town appears to have increasing effects 3 years after the end of the project, substantially reducing overweight and obesity by 6% points in new cohorts of children, 6 years after the original baseline. An apparent and unanticipated 'spillover' of effects into the surrounding region appeared to have occurred with 10%-point reductions in childhood overweight and obesity over the same time period. A 'viral-like' spread of obesity prevention efforts may be becoming possible and an increase in endogenous community activities appears to be surprisingly successful in reducing childhood obesity prevalence. BACKGROUND: The long-term evaluations of community-based childhood obesity prevention interventions are needed to determine their sustainability and scalability. OBJECTIVES: To measure the impacts of the successful Be Active Eat Well (BAEW) programme in Victoria, Australia (2003-2006), 3 years after the programme finished (2009). METHODS: A serial cross-sectional study of children in six intervention and 10 comparison primary schools in 2003 (n = 1674, response rate 47%) and 2009 (n = 1281, response rate 37%). Height, weight, lunch box audits, self-reported behaviours and economic investment in obesity prevention were measured. RESULTS: Compared with 2003, the 2009 prevalence of overweight/obesity (World Health Organization criteria) was significantly lower (P < 0.001) in both intervention (39.2% vs. 32.8%) and comparison (39.6% vs. 29.1%) areas, as was the mean standardized body mass index (0.79 vs. 0.65, 0.77 vs. 0.57, respectively) with no significant differences between areas. Some behaviours improved and a few deteriorated with any group differences favouring the comparison area. In 2009, the investment in obesity prevention in intervention schools was about 30 000 Australian dollars (AUD) per school per year, less than half the amount during BAEW. By contrast, the comparison schools increased from a very low base to over 66 000 AUD per school per year in 2009. CONCLUSIONS: The 8%-point reduction in overweight/obesity in both areas over 6 years from baseline to 3 years post-intervention was substantial. While the benefits of BAEW increased in the intervention community in the long term, the surrounding communities appeared to have more than caught up in programme investments and health gains, suggesting a possible 'viral spread' of obesity prevention actions across the wider region.

The Pacific Obesity Prevention in Communities project: project overview and methods.

Obesity is increasing worldwide with the Pacific region having the highest prevalence among adults. The most common precursor of adult obesity is adolescent obesity making this a critical period for prevention. The Pacific Obesity Prevention in Communities project was a four-country project (Fiji, Tonga, New Zealand and Australia) designed to prevent adolescent obesity. This paper overviews the project and the methods common to the four countries. Each country implemented a community-based intervention programme promoting healthy eating, physical activity and healthy weight in adolescents. A community capacity-building approach was used, with common processes employed but with contextualized interventions within each country. Changes in anthropometric, behavioural and perception outcomes were evaluated at the individual level and school environments and community capacity at the settings level. The evaluation tools common to each are described. Additional analytical studies included economic, socio-cultural and policy studies. The project pioneered many areas of obesity prevention research: using multi-country collaboration to build research capacity; testing a capacity-building approach in ethnic groups with very high obesity prevalence; costing complex, long-term community intervention programmes; systematically studying the powerful socio-cultural influences on weight gain; and undertaking a participatory, national, priority-setting process for policy interventions using simulation modelling of cost-effectiveness of interventions.

Reducing unhealthy weight gain in Fijian adolescents: results of the Healthy Youth Healthy Communities study.

Obesity is a significant problem among adolescents in Pacific populations. This paper reports on the outcomes of a 3-year obesity prevention study, Healthy Youth Healthy Communities, which was part of the Pacific Obesity Prevention in Communities project, undertaken with Fijian adolescents. The intervention was developed with schools and comprised social marketing, nutrition and physical activity initiatives and capacity building designed to reduce unhealthy weight, and the individual exposure period was just over 2-year duration. The evaluation incorporated a quasi-experimental, longitudinal design in seven intervention secondary schools near Suva (n=874) and a matched sample of 11 comparison secondary schools from western Viti Levu (n=2,062). There were significant differences between groups at baseline; the intervention group was shorter, weighed less, had a higher proportion of underweight and lower proportion of overweight, and better quality of life (Pediatric Quality of Life Inventory only). At follow-up, the intervention group had lower percentage body fat (-1.17) but also a lower increase in quality of life (Assessment of Quality of Life instrument: -0.02; Pediatric Quality of Life Inventory: -1.94) than the comparison group. There were no other differences in anthropometry, and behaviours' changes showed a mixed pattern. In conclusion, this school-based health promotion programme lowered percentage body fat but did not reduce unhealthy weight gain or influence most obesity-promoting behaviours among Fijian adolescents. Despite growing evidence supporting the efficacy of community-based approaches to reduce obesity among children of European descent, findings from this study failed to demonstrate the efficacy of a community capacity-building approach among an adolescent sample drawn from a different sociocultural, economic and geographical context. Additional 'top-down' or other innovative approaches may be needed to reduce adolescent obesity in the Pacific.

Reduction in overweight and obesity from a 3-year community-based intervention in Australia: the 'It's Your Move!' project.

'It's Your Move!' was a 3-year intervention study implemented in secondary schools in Australia as part of the Pacific Obesity Prevention In Communities Project. This paper reports the outcome results of anthropometric indices and relevant obesity-related behaviours. The interventions focused on building the capacity of families, schools and communities to promote healthy eating and physical activity. Baseline response rates and follow-up rates were 53% and 69% respectively for the intervention group (n=5 schools) and 47% and 66% respectively for the comparison group (n=7 schools). Statistically significant relative reductions in the intervention versus comparison group were observed: weight (-0.74 kg, P < 0.04), and standardized body mass index (-0.07, P<0.03), and non-significant reductions in prevalence of overweight and obesity (0.75 odds ratio, P=0.12) and body mass index (-0.22, P=0.06). Obesity-related behavioural variables showed mixed results with no pattern of positive intervention outcomes. In conclusion, this is the first study to show that long-term, community-based interventions using a capacity-building approach can prevent unhealthy weight gain in adolescents. Obesity prevention efforts in this important transitional stage of life can be successful and these findings need to be translated to scale for a national effort to reverse the epidemic in children and adolescents.

Outcome results for the Ma'alahi Youth Project, a Tongan community-based obesity prevention programme for adolescents.

Tonga has a very high prevalence of obesity with steep increases during youth, making adolescence a critical time for obesity prevention. The Ma'alahi Youth Project, the Tongan arm of the Pacific Obesity Prevention in Communities project, was a 3-year, quasi-experimental study of community-based interventions among adolescents in three districts on Tonga's main island (Tongatapu) compared to the island of Vava'u. Interventions focused mainly on capacity building, social marketing, education and activities promoting physical activity and local fruit and vegetables. The evaluation used a longitudinal design (mean follow-up duration 2.4 years). Both intervention and comparison groups showed similar large increases in overweight and obesity prevalence (10.1% points, n = 815; 12.6% points, n = 897 respectively). Apart from a small relative decrease in percentage body fat in the intervention group (-1.5%, P < 0.0001), there were no differences in outcomes for any anthropometric variables between groups and behavioural changes did not follow a clear positive pattern. In conclusion, the Ma'alahi Youth Project had no impact on the large increase in prevalence of overweight and obesity among Tongan adolescents. Community-based interventions in such populations with high obesity prevalence may require more intensive or longer interventions, as well as specific strategies targeting the substantial socio-cultural barriers to achieving a healthy weight.

Induction of osteoclasts from CD14-positive human peripheral blood mononuclear cells by receptor activator of nuclear factor kappaB ligand (RANKL).

Osteoclasts are bone-resorbing cells that are derived from haemopoietic precursors, including cells present in peripheral blood. The recent identification of RANKL [receptor activator of nuclear factor (NF)-kappaB ligand], a new member of the tumour necrosis factor ligand superfamily that has a key role in osteoclastogenesis, has allowed the in vitro generation of osteoclasts in the absence of cells of the stromal/osteoblast lineage. Human peripheral blood mononuclear cells (PBMC) cultured in vitro with soluble RANKL and human macrophage colony-stimulating factor form osteoclasts. However, PBMC are heterogeneous, consisting of subsets of monocytes and lymphocytes as well as other blood cells. As the CD14 marker is strongly expressed on monocytes, the putative osteoclast precursor in peripheral blood, we have selected CD14(+) cells from PBMC to examine their osteoclastogenic potential and their expression of novel members of the tumour necrosis factor superfamily involved in osteoclastogenesis. Highly purified CD14(+) cells demonstrated mRNA expression of receptor activator of NF-kappaB, but no expression of RANKL or osteoprotegerin, whereas PBMC expressed mRNAs for all three factors. CD14(+) (but not CD14(-)) cells cultured on bone slices for 21 days with human macrophage colony-stimulating factor and soluble RANKL generated osteoclasts and showed extensive bone resorption. Similar numbers of osteoclasts were generated by 10(5) CD14(+) cells and 10(6) PBMC, but there was significantly less intra-assay variability with CD14(+) cells, suggesting the absence of stimulatory/inhibitory factors from these cultures. The ability of highly purified CD14(+) cells to generate osteoclasts will facilitate further characterization of the phenotype of circulating osteoclast precursors and cell interactions in osteoclastogenesis.

Expression of functional RANK on mature rat and human osteoclasts.

Although the important roles of RANK/RANKL in osteoclastogenesis have been established, their roles in the regulation of mature osteoclasts remain uncertain. Microisolation has been used to obtain pure populations of rat and human osteoclasts for RT-PCR analysis. RANK and calcitonin receptor mRNA was detected in all the samples whereas OPG and ALP mRNA was not present in any. RANKL mRNA was detected in two of eight rat and one of four human samples. Treatment of osteoclasts with soluble RANKL resulted in translocation of NF-kappaB to the nucleus and elevation of cytosolic and nuclear calcium levels. We have shown that RANK is highly expressed in mature osteoclasts and that its stimulation by RANKL results in activation of NF-kappaB and calcium signalling.