The health and economic impact and cost effectiveness of interventions for the prevention and control of overweight and obesity in Kenya: a stakeholder engaged modelling study.

BACKGROUND: The global increase in mean body mass index has resulted in a substantial increase of non-communicable diseases (NCDs), including in many low- and middle-income countries such as Kenya. This paper assesses four interventions for the prevention and control of overweight and obesity in Kenya to determine their potential health and economic impact and cost effectiveness. METHODS: We reviewed the literature to identify evidence of effect, determine the intervention costs, disease costs and total healthcare costs. We used a proportional multistate life table model to quantify the potential impacts on health conditions and healthcare costs, modelling the 2019 Kenya population over their remaining lifetime. Considering a health system perspective, two interventions were assessed for cost-effectiveness. In addition, we used the Human Capital Approach to estimate productivity gains. RESULTS: Over the lifetime of the 2019 population, impacts were estimated at 203,266 health-adjusted life years (HALYs) (95% uncertainty interval [UI] 163,752 - 249,621) for a 20% tax on sugar-sweetened beverages, 151,718 HALYs (95% UI 55,257 - 250,412) for mandatory kilojoule menu labelling, 3.7 million HALYs (95% UI 2,661,365-4,789,915) for a change in consumption levels related to supermarket food purchase patterns and 13.1 million HALYs (95% UI 11,404,317 - 15,152,341) for a change in national consumption back to the 1975 average levels of energy intake. This translates to 4, 3, 73 and 261 HALYs per 1,000 persons. Lifetime healthcare cost savings were approximately United States Dollar (USD) 0.14 billion (USD 3 per capita), USD 0.08 billion (USD 2 per capita), USD 1.9 billion (USD 38 per capita) and USD 6.2 billion (USD 124 per capita), respectively. Lifetime productivity gains were approximately USD 1.8 billion, USD 1.2 billion, USD 28 billion and USD 92 billion. Both the 20% tax on sugar sweetened beverages and the mandatory kilojoule menu labelling were assessed for cost effectiveness and found dominant (health promoting and cost-saving). CONCLUSION: All interventions evaluated yielded substantive health gains and economic benefits and should be considered for implementation in Kenya.

Avoidable burden of stomach cancer and potential gains in healthy life years from gradual reductions in salt consumption in Vietnam, 2019-2030: a modelling study.

OBJECTIVE: Excess salt consumption is causally linked with stomach cancer, and salt intake among adults in Vietnam is about twice the recommended levels. The aim of this study was to quantify the future burden of stomach cancer that could be avoided from population-wide salt reduction in Vietnam. DESIGN: A dynamic simulation model was developed to quantify the impacts of achieving the 2018 National Vietnam Health Program (8 g/d by 2025 and 7 g/d by 2030) and the WHO (5 g/d) salt reduction policy targets. Data on salt consumption were obtained from the Vietnam 2015 WHO STEPS survey. Health outcomes were estimated over 6-year (2019-2025), 11-year (2019-2030) and lifetime horizons. We conducted one-way and probabilistic sensitivity analyses. SETTING: Vietnam. PARTICIPANTS: All adults aged ≥ 25 years (61 million people, 48·4 % men) alive in 2019. RESULTS: Achieving the 2025 and 2030 national salt targets could result in 3400 and 7200 fewer incident cases of stomach cancer, respectively, and avert 1900 and 4800 stomach cancer deaths, respectively. Achieving the WHO target by 2030 could prevent 8400 incident cases and 5900 deaths from stomach cancer. Over the lifespan, this translated to 344 660 (8 g/d), 411 060 (7 g/d) and 493 633 (5 g/d) health-adjusted life years gained, respectively. CONCLUSIONS: A sizeable burden of stomach cancer could be avoided, with gains in healthy life years if national and WHO salt targets were attained. Our findings provide impetus for policy makers in Vietnam and Asia to intensify salt reduction strategies to combat stomach cancer and mitigate pressure on the health systems.

Stakeholder-engaged research: strategies for the prevention and control of overweight and obesity in Kenya.

BACKGROUND: This study was done as part of a larger study that aims to identify the most impactful and cost-effective strategies for the prevention and control of overweight and obesity in Kenya. Our objective was to involve stakeholders in the identification of the strategies that would be included in our larger study. The results from the stakeholder engagement are analyzed and reported in this paper. DESIGN: This was a qualitative study. A one-day stakeholder workshop that followed a deliberative dialogue process was conducted. PARTICIPANTS: A sample of stakeholders who participate in the national level policymaking process for health in Kenya. OUTCOME MEASURE: Strategies for the prevention and control of overweight and obesity in Kenya. RESULTS: Out of the twenty-three stakeholders who confirmed attendance, fifteen participants attended the one-day workshop. The stakeholders identified a total of 24 strategies for the prevention and control of overweight and obesity in Kenya. From the ranking process carried out the top six strategies identified were: a research-based strategy for the identification of the nutritional value of indigenous foods, implementation of health promotion strategies that focus on the creation of healthy environments, physical activity behavior such as gym attendance, jogging, walking, and running at the individual level, implementation of school curricula on nutrition and health promotion, integration of physical education into the new Competency-Based Education policy, and policies that increase use of public transport. CONCLUSION: The stakeholders identified and ranked strategies for the prevention and control of overweight and obesity in Kenya. This informs future overweight and obesity prevention research and policy in Kenya and similar settings.

Estimation and determinants of direct medical costs of ischaemic heart disease, stroke and hypertensive heart disease: evidence from two major hospitals in Cameroon.

BACKGROUND: Cardiovascular disease (CVD) is the largest contributor to the non-communicable diseases (NCD) burden in Cameroon, but data on its economic burden is lacking. METHODS: A prevalence-based cost-of-illness study was conducted from a healthcare provider perspective and enrolled patients with ischaemic heart disease (IHD), ischaemic stroke, haemorrhagic stroke and hypertensive heart disease (HHD) from two major hospitals between 2013 and 2017. Determinants of cost were explored using multivariate generalized linear models. RESULTS: Overall, data from 850 patients: IHD (n = 92, 10.8%), ischaemic stroke (n = 317, 37.3%), haemorrhagic stroke (n = 193, 22.7%) and HHD (n = 248, 29.2%) were analysed. The total cost for these CVDs was XAF 676,694,000 (~US$ 1,224,918). The average annual direct medical costs of care per patient were XAF 1,395,200 (US$ 2400) for IHD, XAF 932,700 (US$ 1600) for ischaemic stroke, XAF 815,400 (US$ 1400) for haemorrhagic stroke, and XAF 384,300 (US$ 700) for HHD. In the fully adjusted models, apart from history of CVD event (ß = - 0.429; 95% confidence interval - 0.705, - 0.153) that predicted lower costs in patients with IHD, having of diabetes mellitus predicted higher costs in patients with IHD (ß = 0.435; 0.098, 0.772), ischaemic stroke (ß = 0.188; 0.052, 0.324) and HHD (ß = 0.229; 0.080, 0.378). CONCLUSIONS: This study reveals substantial economic burden due to CVD in Cameroon. Diabetes mellitus was a consistent driver of elevated costs across the CVDs. There is urgent need to invest in cost-effective primary prevention strategies in order to reduce the incidence of CVD and consequent economic burden on a health system already laden with the impact of communicable diseases.

Estimated health benefits, costs, and cost-effectiveness of eliminating industrial trans-fatty acids in Australia: A modelling study.

BACKGROUND: trans-fatty acids (TFAs) are a well-known risk factor of ischemic heart disease (IHD). In Australia, the highest TFA intake is concentrated to the most socioeconomically disadvantaged groups. Elimination of industrial TFA (iTFA) from the Australian food supply could result in reduced IHD mortality and morbidity while improving health equity. However, such legislation could lead to additional costs for both government and food industry. Thus, we assessed the potential cost-effectiveness, health gains, and effects on health equality of an iTFA ban from the Australian food supply. METHODS AND FINDINGS: Markov cohort models were used to estimate the impact on IHD burden and health equity, as well as the cost-effectiveness of a national ban of iTFA in Australia. Intake of TFA was assessed using the 2011-2012 Australian National Nutrition and Physical Activity Survey. The IHD burden attributable to TFA was calculated by comparing the current level of TFA intake to a counterfactual setting where consumption was lowered to a theoretical minimum distribution with a mean of 0.5% energy per day (corresponding to TFA intake only from nonindustrial sources, e.g., dairy foods). Policy costs, avoided IHD events and deaths, health-adjusted life years (HALYs) gained, and changes in IHD-related healthcare costs saved were estimated over 10 years and lifetime of the adult Australian population. Cost-effectiveness was assessed by calculation of incremental cost-effectiveness ratios (ICERs) using net policy cost and HALYs gained. Health benefits and healthcare cost changes were also assessed in subgroups based on socioeconomic status, defined by Socio-Economic Indexes for Areas (SEIFA) quintile, and remoteness. Compared to a base case of no ban and current TFA intakes, elimination of iTFA was estimated to prevent 2,294 (95% uncertainty interval [UI]: 1,765; 2,851) IHD deaths and 9,931 (95% UI: 8,429; 11,532) IHD events over the first 10 years. The greatest health benefits were accrued to the most socioeconomically disadvantaged quintiles and among Australians living outside of major cities. The intervention was estimated to be cost saving (net cost <0 AUD) or cost-effective (i.e., ICER < AUD 169,361/HALY) regardless of the time horizon, with ICERs of 1,073 (95% UI: dominant; 3,503) and 1,956 (95% UI: 1,010; 2,750) AUD/HALY over 10 years and lifetime, respectively. Findings were robust across several sensitivity analyses. Key limitations of the study include the lack of recent data of TFA intake and the small sample sizes used to estimate intakes in subgroups. As with all simulation models, our study does not prove that a ban of iTFA will prevent IHD, rather, it provides the best quantitative estimates and corresponding uncertainty of a potential effect in the absence of stronger direct evidence. CONCLUSIONS: Our model estimates that a ban of iTFAs could avert substantial numbers of IHD events and deaths in Australia and would likely be a highly cost-effective strategy to reduce social-economic and urban-rural inequalities in health. These findings suggest that elimination of iTFA can cost-effectively improve health and health equality even in countries with low iTFA intake.

Effectiveness of school-based nutrition interventions in sub-Saharan Africa: a systematic review.

OBJECTIVE: To evaluate the effect of school-based nutrition interventions (SBNI) involving schoolchildren and adolescents in sub-Saharan Africa (SSA) on child nutrition status and nutrition-related knowledge, attitudes and behaviour. DESIGN: A systematic review on published school nutrition intervention studies of randomised controlled trials, controlled clinical trials, controlled before-and-after studies or quasi-experimental designs with control. Nine electronic bibliographic databases were searched. To be included, interventions had to involve changes to the school's physical and social environments, to the school's nutrition policies, to teaching curriculum to incorporate nutrition education and/or to partnership with parents/community. SETTING: Schools in SSA. PARTICIPANTS: School-aged children and adolescents, aged 5-19 years. RESULTS: Fourteen studies met our inclusion criteria. While there are few existing studies of SBNI in SSA, the evidence shows that food supplementation/fortification is very effective in reducing micronutrient deficiencies and can improve nutrition status. Secondly, school nutrition education can improve nutrition knowledge, but this may not necessarily translate into healthy nutrition behaviour, indicating that nutrition knowledge may have little impact without a facilitating environment. Results regarding anthropometry were inconclusive; however, there is evidence for the effectiveness of SBNI in improving cognitive abilities. CONCLUSIONS: There is enough evidence to warrant further trials of SBNI in SSA. Future research should consider investigating the impact of SBNI on anthropometry and nutrition behaviour, focusing on the role of programme intensity and/or duration. To address the high incidence of micronutrient deficiencies in low- and middle-income countries, food supplementation strategies currently available to schoolchildren should be expanded.

Exploring the association between BMI and mortality in Australian women and men with and without diabetes: the AusDiab study.

AIMS/HYPOTHESIS: There is conflicting evidence about the obesity paradox-the counterintuitive survival advantage of obesity among certain subpopulations of individuals with chronic conditions. It is believed that results supporting the obesity paradox are due to methodological flaws, such as collider bias. The aim of this study was to examine the association between obesity and mortality in Australian men and women. In addition, we explored whether obesity would appear to be protective if the analysis was restricted to a subpopulation with disease, and to discuss the potential role of collider bias in producing such a result. METHODS: The examined cohort included 10,575 Australian adults (4844 men and 5731 women) aged 25-91 years who were recruited for the AusDiab baseline survey in 1999 and followed-up through 2014. The main predictor variable was BMI categorised as normal weight (18.5 to <25 kg/m2), overweight (25 to <30 kg/m2) and obese (≥30 kg/m2), and the outcome of interest was all-cause mortality. Hazard ratios were estimated from Cox proportional hazards regression models in the entire cohort and then in subpopulations with and without diabetes. RESULTS: A total of 1477 deaths occurred during 145,384 person-years (median 14.6 years) of follow-up. Mortality was higher in obese than in normal-weight individuals for the full population (HR 1.18; 95% CI 1.05, 1.32). When an interaction between diabetes status and BMI category was added to the model, there was no evidence of an interaction between BMI and diabetes status (p = 0.92). When participants with and without diabetes were analysed separately, there was no evidence of an association between obesity and mortality in those with diabetes (HR 0.91; 95% CI 0.62, 1.33). CONCLUSIONS/INTERPRETATION: In the entire AusDiab cohort, we found a significantly higher mortality among obese participants as compared with their normal-weight counterparts. We found no difference in the obesity-mortality association between individuals with and without diabetes.

Intellectual disability and autism: socioeconomic impacts of informal caring, projected to 2030.

BACKGROUND: Intellectual disability and autism spectrum disorder (ASD) influence the interactions of a person with their environment and generate economic and socioeconomic costs for the person, their family and society. AIMS: To estimate costs of lost workforce participation due to informal caring for people with intellectual disability or autism spectrum disorders by estimating lost income to individuals, lost taxation payments to federal government and increased welfare payments. METHOD: We used a microsimulation model based on the Australian Bureau of Statistics' Surveys of Disability, Ageing and Carers (population surveys of people aged 15-64), and projected costs of caring from 2015 in 5-year intervals to 2030. RESULTS: The model estimated that informal carers of people with intellectual disability and/or ASD in Australia had aggregated lost income of AU$310 million, lost taxation of AU$100 million and increased welfare payments of AU$204 million in 2015. These are projected to increase to AU$432 million, AU$129 million and AU$254 million for income, taxation, and welfare respectively by 2030. The income gap of carers for people with intellectual disability and/or ASD is estimated to increase by 2030, meaning more financial stress for carers. CONCLUSIONS: Informal carers of people with intellectual disability and/or ASD experience significant loss of income, leading to increased welfare payments and reduced taxation revenue for governments; these are all projected to increase. Strategic policies supporting informal carers wishing to return to work could improve the financial and psychological impact of having a family member with intellectual disability and/or ASD. DECLARATION OF INTEREST: None.

Physical activity-related health and economic benefits of building walkable neighbourhoods: a modelled comparison between brownfield and greenfield developments.

BACKGROUND: A consensus is emerging in the literature that urban form can impact health by either facilitating or deterring physical activity (PA). However, there is a lack of evidence measuring population health and the economic benefits relating to alternative urban forms. We examined the issue of housing people within two distinct types of urban development forms: a medium-density brownfield development in an established area with existing amenities (e.g. daily living destinations, transit), and a low-density suburban greenfield development. We predicted the health and economic benefits of a brownfield development compared with a greenfield development through their influence on PA. METHODS: We combined a new Walkability Planning Support System (Walkability PSS) with a quantitative health impact assessment model. We used the Walkability PSS to estimate the probability of residents' transport walking, based on their exposure to urban form in the brownfield and greenfield developments. We developed the underlying algorithms of the Walkability PSS using multi-level multivariate logistic regression analysis based on self-reported data for transport walking from the Victorian Integrated Survey of Transport and Activity 2009-10 and objectively measured urban form in the developments. We derived the difference in transport walking minutes per week based on the probability of transport walking in each of the developments and the average transport walking time per week among those who reported any transport walking. We then used the well-established method of the proportional multi-cohort multi-state life table model to translate the difference in transport walking minutes per week into health and economic benefits. RESULTS: If adult residents living in the greenfield neighbourhood were instead exposed to the urban development form observed in a brownfield neighbourhood, the incidence and mortality of physical inactivity-related chronic diseases would decrease. Over the life course of the exposed population (21,000), we estimated 1600 health-adjusted life years gained and economic benefits of A$94 million. DISCUSSION: Our findings indicate that planning policies that create walkable neighbourhoods with access to shops, services and public transport will lead to substantial health and economic benefits associated with reduced incidence of physical inactivity related diseases and premature death.

Primary and secondary prevention interventions for cardiovascular disease in low-income and middle-income countries: a systematic review of economic evaluations.

BACKGROUND: Cardiovascular disease (CVD) is the leading cause of deaths globally, with greatest premature mortality in the low- and middle-income countries (LMIC). Many of these countries, especially in sub-Saharan Africa, have significant budget constraints. The need for current evidence on which interventions offer good value for money to stem this CVD epidemic motivates this study. METHODS: In this systematic review, we included studies reporting full economic evaluations of individual and population-based interventions (pharmacologic and non-pharmacologic), for primary and secondary prevention of CVD among adults in LMIC. Several medical (PubMed, EMBASE, SCOPUS, Web of Science) and economic (EconLit, NHS EED) databases and grey literature were searched. Screening of studies and data extraction was done independently by two reviewers. Drummond's checklist and the National Institute for Health and Care Excellence quality rating scale were used in the quality appraisal for all studies used to inform this evidence synthesis. RESULTS: From a pool of 4059 records, 94 full texts were read and 50 studies, which met our inclusion criteria, were retained for our narrative synthesis. Most of the studies were from middle-income countries and predominantly of high quality. The majority were modelled evaluations, and there was significant heterogeneity in methods. Primary prevention studies dominated secondary prevention. Most of the economic evaluations were performed for pharmacological interventions focusing on blood pressure, cholesterol lowering and antiplatelet aggregants. The greatest majority were cost-effective. Compared to individual-based interventions, population-based interventions were few and mostly targeted reduction in sodium intake and tobacco control strategies. These were very cost-effective with many being cost-saving. CONCLUSIONS: This evidence synthesis provides a contemporary update on interventions that offer good value for money in LMICs. Population-based interventions especially those targeting reduction in salt intake and tobacco control are very cost-effective in LMICs with potential to generate economic gains that can be reinvested to improve health and/or other sectors. While this evidence is relevant for policy across these regions, decision makers should additionally take into account other multi-sectoral perspectives, including considerations in budget impact, fairness, affordability and implementation while setting priorities for resource allocation.

The Population Mean Mood Predicts The Prevalence of Depression in an Australian Context.

BACKGROUND: The mean population mood has been demonstrated to strongly correlate with the prevalence of depression in European populations. Mean population mood has, therefore, been proposed as both a metric to measure the impact of population-level interventions to prevent depression and a target for public health policy. AIM: To demonstrate the relationship between mean population mood and the prevalence of depression using Australian data in order to broaden the applicability of this finding to the Australian population. METHODS: We used data from the Geelong Osteoporosis Study to assess the relationship between population mean mood and depression. Participants reported mood symptoms via questionnaire (the Hospital Anxiety and Depression Scale or General Health Questionnaire-12). Depression was diagnosed by semi-structured clinical interview ( Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Non-patient Edition). Stratification by age and socio-economic status was used to create subpopulation groups. Socio-economic status was measured using Index of Relative Socio-economic Advantage and Disadvantage quintiles, an area-based measure based on Australian census data and published by the Australian Bureau of Statistics. The mean subpopulation questionnaire scores and subpopulation prevalence of depression were then analysed using regression and predictive models. RESULTS: Mean subpopulation questionnaire scores correlated well with the prevalence of depression across socio-economic status groups in women but not age groups. Questionnaire scores tended to underestimate the prevalence of depression in the young and overestimate it in the elderly. CONCLUSION: The mean population mood was demonstrated to correlate with the population prevalence of depression in Australia for women, but not for men. Due to the issues of questionnaire validity and sample size in the oldest age groups, the age analysis is unlikely to be a representative of population characteristics. Further work to identify population determinants of mean mood could potentially create policy targets to reduce the prevalence of depression.

Population awareness of cardiovascular disease and its risk factors in Buea, Cameroon.

BACKGROUND: Adequate awareness of cardiovascular diseases (CVD) and their risk factors may help reduce the population's exposure to modifiable risk factors and thereby contribute to prevention and control strategies. There is limited data on knowledge among the general population in sub-Saharan Africa regarding CVD and risk factors. We aimed to assess the population awareness (and associated factors) of CVD types and risk factors in Buea, Cameroon. METHODS: This was a community-based cross-sectional study conducted in 2016 among randomly selected adults (>18 years). Data on socio-demographic characteristics, knowledge about CVD types, their risk factors and warning signs for CVD events (stroke and heart attack) were acquired using a self-administered questionnaire. Logistic regression analysis was used to investigate factors associated with moderate-to-good knowledge. RESULTS: Of the 1162 participants (61.7% women, mean age 32 years), 52.5% had overall poor knowledge (mean score 12.1 on total of 25) on CVD with only about a quarter correctly identifying types of CVD. Overall, 36, 63 and 45% were unaware of CVD risk factors, warning signs of heart attack and stroke respectively. In multivariable analysis; high level of education (aOR = 2.26 (1.69-3.02), p < 0.0001), high monthly income (aOR = 1.64 (1.07-2.51), p = 0.023), having a family history of CVD (aOR = 1.59 (1.21-2.09), p = 0.001) and being a former smoker (aOR = 1.11 (1.02-1.95), p = 0.043) were associated with moderate-to-good knowledge. CONCLUSIONS: There exists a significant gap in population awareness about CVDs in Cameroon and this is similar to previous reports. Cost-effective community health education interventions taking into account socioeconomic status may be beneficial in this setting.

Living well after breast cancer randomized controlled trial protocol: evaluating a telephone-delivered weight loss intervention versus usual care in women following treatment for breast cancer.

BACKGROUND: Obesity, physical inactivity and poor diet quality have been associated with increased risk of breast cancer-specific and all-cause mortality as well as treatment-related side-effects in breast cancer survivors. Weight loss intervention trials in breast cancer survivors have shown that weight loss is safe and achievable; however, few studies have examined the benefits of such interventions on a broad range of outcomes and few have examined factors important to translation (e.g. feasible delivery method for scaling up, assessment of sustained changes, cost-effectiveness). The Living Well after Breast Cancer randomized controlled trial aims to evaluate a 12-month telephone-delivered weight loss intervention (versus usual care) on weight change and a range of secondary outcomes including cost-effectiveness. METHODS/DESIGN: Women (18-75 years; body mass index 25-45 kg/m2) diagnosed with stage I-III breast cancer in the previous 2 years are recruited from public and private hospitals and through the state-based cancer registry (target n = 156). Following baseline assessment, participants are randomized 1:1 to either a 12-month telephone-delivered weight loss intervention (targeting diet and physical activity) or usual care. Data are collected at baseline, 6-months (mid-intervention), 12-months (end-of-intervention) and 18-months (maintenance). The primary outcome is change in weight at 12-months. Secondary outcomes are changes in body composition, bone mineral density, cardio-metabolic and cancer-related biomarkers, metabolic health and chronic disease risk, physical function, patient-reported outcomes (quality of life, fatigue, menopausal symptoms, body image, fear of cancer recurrence) and behaviors (dietary intake, physical activity, sitting time). Data collected at 18-months will be used to assess whether outcomes achieved at end-of-intervention are sustained six months after intervention completion. Cost-effectiveness will be assessed, as will mediators and moderators of intervention effects. DISCUSSION: This trial will provide evidence needed to inform the wide-scale provision of weight loss, physical activity and dietary interventions as part of routine survivorship care for breast cancer survivors. TRIAL REGISTRATION: Australian and New Zealand Clinical Trial Registry (ANZCTR) - ACTRN12612000997853 (Registered 18 September 2012).

The association between built environment features and physical activity in the Australian context: a synthesis of the literature.

BACKGROUND: There is growing evidence indicating that the built environment is a determinant of physical activity. However, despite the well-established health benefits of physical activity this is rarely considered in urban planning. We summarised recent Australian evidence for the association built environment-physical activity among adults. This summary aims to inform policy makers who advocate for the consideration of health in urban planning. METHODS: A combination of built environment and physical activity terms were used to systematically identify relevant peer reviewed and grey literature. RESULTS: A total of 23 studies were included, providing 139 tests of associations between specific built environment features and physical activity. Of the total, 84 relationships using objective measures of built environment attributes were evaluated, whereas 55 relationships using self-reported measures were evaluated. Our results indicate that walkable neighbourhoods with a wide range of local destinations to go to, as well as a diverse use of land, encourage physical activity among their residents. CONCLUSIONS: This research provides a summary of recent Australian evidence on built environments that are most favourable for physical activity. Features of walkability and availability of destinations within walking distance should be accounted for in the development or redevelopment of urban areas. Our findings emphasise the importance of urban planning for health via its impact on population levels of physical activity.

Depression prevention, labour force participation and income of older working aged Australians: A microsimulation economic analysis.

OBJECTIVE: Depression has economic consequences not only for the health system, but also for individuals and society. This study aims to quantify the potential economic impact of five-yearly screening for sub-syndromal depression in general practice among Australians aged 45-64 years, followed by a group-based psychological intervention to prevent progression to depression. METHOD: We used an epidemiological simulation model to estimate reductions in prevalence of depression, and a microsimulation model, Health&WealthMOD2030, to estimate the impact on labour force participation, personal income, savings, taxation revenue and welfare expenditure. RESULTS: Group therapy is estimated to prevent around 5,200 prevalent cases of depression (2.2%) and add about 520 people to the labour force. Private incomes are projected to increase by $19 million per year, tax revenues by $2.4 million, and transfer payments are reduced by $2.6 million. CONCLUSION: Group-based psychological intervention to prevent depression could result in considerable economic benefits in addition to its clinical effects.

Improving diet and physical activity to reduce population prevalence of overweight and obesity: an overview of current evidence.

OBJECTIVE: The aim of this study is to provide an overview of interventions to reduce or prevent overweight or obesity and improve diet or physical activity. METHODS: A review of meta-analyses and/or systematic reviews of these interventions in any setting or age group were conducted. Narrative systematic reviews were included for intervention categories with limited meta-analyses available. Summary measures including weighted mean difference, standardised mean difference, and I-squared, were examined. RESULTS: A total of 60 meta-analyses and 23 systematic reviews met the inclusion criteria. Dietary interventions and multi-component interventions targeting overweight and obesity appeared to have the greatest effects, particularly in comparison with workplace or technology or internet-based interventions. Pharmaceutical and surgical interventions produced favourable results for specific population sub-groups (i.e. morbidly obese). Population-wide strategies such as policy interventions have not been widely analysed. The effectiveness of the interventions to assist in maintaining behaviour or weight change remains unclear. CONCLUSIONS: Various individually targeted interventions were shown to reduce body weight, although effect sizes were typically modest, and the durability of effects has been questioned. New approaches to evaluating population-based interventions, such as taxes and regulation, are recommended. Future research modelling the long-term effects of interventions across the lifespan would also be beneficial.

Does physical activity prevent cognitive decline and dementia?: A systematic review and meta-analysis of longitudinal studies.

BACKGROUND: By 2050, it has been estimated that approximately one-fifth of the population will be made up of older adults (aged ≥60 years). Old age often comes with cognitive decline and dementia. Physical activity may prevent cognitive decline and dementia. METHODS: We reviewed and synthesised prospective studies into physical activity and cognitive decline, and physical activity and dementia, published until January 2014. Forty-seven cohorts, derived from two previous systematic reviews and an updated database search, were used in the meta-analyses. Included participants were aged ≥40 years, in good health and/or randomly selected from the community. Studies were assessed for methodological quality. RESULTS: Twenty-one cohorts on physical activity and cognitive decline and twenty-six cohorts on physical activity and dementia were included. Meta-analysis, using the quality-effects model, suggests that participants with higher levels of physical activity, when compared to those with lower levels, are at reduced risk of cognitive decline, RR 0.65, 95% CI 0.55-0.76, and dementia, RR 0.86, 95% CI 0.76-0.97. Sensitivity analyses revealed a more conservative estimate of the impact of physical activity on cognitive decline and dementia for high quality studies, studies reporting effect sizes as ORs, greater number of adjustments (≥10), and longer follow-up time (≥10 years). When one heavily weighted study was excluded, physical activity was associated with an 18% reduction in the risk of dementia (RR 0.82; 0.73-0.91). CONCLUSIONS: Longitudinal observational studies show an association between higher levels of physical activity and a reduced risk of cognitive decline and dementia. A case can be made for a causal interpretation. Future research should use objective measures of physical activity, adjust for the full range of confounders and have adequate follow-up length. Ideally, randomised controlled trials will be conducted. Regardless of any effect on cognition, physical activity should be encouraged, as it has been shown to be beneficial on numerous levels.

Estimated health benefits, costs and cost-effectiveness of eliminating industrial trans-fatty acids in Nigeria: cost-effectiveness analysis.

INTRODUCTION: Nigeria is committed to reducing industrial trans-fatty acids (iTFA) from the food supply, but the potential health gains, costs and cost-effectiveness are unknown. METHODS: The effect on ischaemic heart disease (IHD) burden, costs and cost-effectiveness of a mandatory iTFA limit (≤2% of all fats) for foods in Nigeria were estimated using Markov cohort models. Data on demographics, IHD epidemiology and trans-fatty acid intake were derived from the 2019 Global Burden of Disease Study. Avoided IHD events and deaths; health-adjusted life years (HALYs) gained; and healthcare, policy implementation and net costs were estimated over 10 years and the population's lifetime. Incremental cost-effectiveness ratios using net costs and HALYs gained (both discounted at 3%) were used to assess cost-effectiveness. RESULTS: Over the first 10 years, a mandatory iTFA limit (assumed to eliminate iTFA intake) was estimated to prevent 9996 (95% uncertainty interval: 8870 to 11 118) IHD deaths and 66 569 (58 862 to 74 083) IHD events, and to save US$90 million (78 to 102) in healthcare costs. The corresponding lifetime estimates were 259 934 (228 736 to 290 191), 479 308 (95% UI 420 472 to 538 177) and 518 (450 to 587). Policy implementation costs were estimated at US$17 million (11 to 23) over the first 10 years, and US$26 million USD (19 to 33) over the population's lifetime. The intervention was estimated to be cost-saving, and findings were robust across several deterministic sensitivity analyses. CONCLUSION: Our findings support mandating a limit of iTFAs as a cost-saving strategy to reduce the IHD burden in Nigeria.

Evidence that a tax on sugar sweetened beverages reduces the obesity rate: a meta-analysis.

BACKGROUND: Excess intake of sugar sweetened beverages (SSBs) has been shown to result in weight gain. To address the growing epidemic of obesity, one option is to combine programmes that target individual behaviour change with a fiscal policy such as excise tax on SSBs. This study evaluates the literature on SSB taxes or price increases, and their potential impact on consumption levels, obesity, overweight and body mass index (BMI). The possibility of switching to alternative drinks is also considered. METHODS: The following databases were used: Pubmed/Medline, The Cochrane Database of Systematic Reviews, Google Scholar, Econlit, National Bureau of Economics Research (NBER), Research Papers in Economics (RePEc). Articles published between January 2000 and January 2013, which reported changes in diet or BMI, overweight and/or obesity due to a tax on, or price change of, SSBs were included. RESULTS: Nine articles met the criteria for the meta-analysis. Six were from the USA and one each from Mexico, Brazil and France. All showed negative own-price elasticity, which means that higher prices are associated with a lower demand for SSBs. Pooled own price-elasticity was -1.299 (95% CI: -1.089 - -1.509). Four articles reported cross-price elasticities, three from the USA and one from Mexico; higher prices for SSBs were associated with an increased demand for alternative beverages such as fruit juice (0.388, 95% CI: 0.009 - 0.767) and milk (0.129, 95% CI: -0.085 - 0.342), and a reduced demand for diet drinks (-0.423, 95% CI: -0.628 - -1.219). Six articles from the USA showed that a higher price could also lead to a decrease in BMI, and decrease the prevalence of overweight and obesity. CONCLUSIONS: Taxing SSBs may reduce obesity. Future research should estimate price elasticities in low- and middle-income countries and identify potential health gains and the wider impact on jobs, monetary savings to the health sector, implementation costs and government revenue. Context-specific cost-effectiveness studies would allow policy makers to weigh these factors.