Cross-model validation of public health microsimulation models; comparing two models on estimated effects of a weight management intervention.

BACKGROUND: Health economic modelling indicates that referral to a behavioural weight management programme is cost saving and generates QALY gains compared with a brief intervention. The aim of this study was to conduct a cross-model validation comparing outcomes from this cost-effectiveness analysis to those of a comparator model, to understand how differences in model structure contribute to outcomes. METHODS: The outcomes produced by two models, the School for Public Health Research diabetes prevention (SPHR) and Health Checks (HC) models, were compared for three weight-management programme strategies; Weight Watchers (WW) for 12 weeks, WW for 52 weeks, and a brief intervention, and a simulated no intervention scenario. Model inputs were standardised, and iterative adjustments were made to each model to identify drivers of differences in key outcomes. RESULTS: The total QALYs estimated by the HC model were higher in all treatment groups than those estimated by the SPHR model, and there was a large difference in incremental QALYs between the models. SPHR simulated greater QALY gains for 12-week WW and 52-week WW relative to the Brief Intervention. Comparisons across socioeconomic groups found a stronger socioeconomic gradient in the SPHR model. Removing the impact of treatment on HbA1c from the SPHR model, running both models only with the conditions that the models have in common and, to a lesser extent, changing the data used to estimate risk factor trajectories, resulted in more consistent model outcomes. CONCLUSIONS: The key driver of difference between the models was the inclusion of extra evidence-based detail in SPHR on the impacts of treatments on HbA1c. The conclusions were less sensitive to the dataset used to inform the risk factor trajectories. These findings strengthen the original cost-effectiveness analyses of the weight management interventions and provide an increased understanding of what is structurally important in the models.

Household food insecurity and child health outcomes: a rapid review of mechanisms and associations.

BACKGROUND: Household food insecurity (HHFI) has detrimental impact on child health outcomes. The primary aim of this work was to describe the mechanisms, defined as statistically quantified processes or systems, that explain the association between HHFI and poor child health outcomes. The secondary aim was to identify which child health outcomes were significantly associated with HHFI. METHODS: In this rapid review, we included real-world evidence studies in children and adolescents aged 3-24 years, from high-income countries. We searched peer-reviewed literature through the databases Medline, Embase, Web of Science and The Cochrane Library on March 10, 2022, with a 15-year time restriction. Key search terms included "food insecurity", "food poverty", "statistics", "structural equation model*", "regression", "conceptual model*", and "theoretical model*". We identified additional studies by searching citations and references. Papers were selected using pre-defined criteria and non-English Language studies were excluded. We extracted summary data of published studies using the Cochrane data extraction template as a guide. We included a broad range of health outcomes to identify what aspects of health are affected by HHFI, including metabolic risk factors (eg, BMI), conditions (eg, depression), biological processes (eg, sleep) and parent-child interactions (eg, feeding styles). We performed a narrative synthesis, as heterogeneity precluded statistical synthesis. We used the Quality in Prognosis Studies tool to assess the mechanism studies. FINDINGS: We included 70 systematic reviews (six mechanism and 64 association reviews) from the UK, Canada, USA, Australia, and Ireland (including 18 887 mechanism studies and 986 759 association studies). Low-to-moderate bias was detected in mechanism studies, and there was variability in HHFI measures. Maternal depression and parenting stress during childhood played a mechanistic role between HHFI and adolescent depression (b=0·008, 95% CI 0·002-0·016) and anxiety (b=0·012, 0·002-0·026). Maternal stress mediated the association between HHFI and child overweight (odds ratio [OR] 1·79, 0·82-3·92, p<0·01), via restrictive feeding styles (OR 1·81, 1·15-2·85, p=0·010) that had negative impact on diet (p<0·01). Ethnicity, income, employment, and education moderated the relationship between HHFI and child health outcomes (p<0·001). INTERPRETATION: Two key mechanistic pathways between HHFI and child health outcomes were diet and mental health of both child and parent, which appeared interrelated. Interventions targeting HHFI in children, should consider these pathways alongside sociodemographic factors. A strength of this review was that it was the first literature summary explaining the mechanisms between HHFI and child health, using evidence from high-income countries. A limitation was that HHFI measures were inconsistent between studies and countries, disallowing study comparisons. FUNDING: University of Sheffield.

Identification of tax options for high fat, sugar, salt foods for the HEALTHEI Project: a mixed-methods study.

BACKGROUND: The health economic analysis incorporating effects on labour outcomes, households, environment, and inequalities (HEALTHEI) explores which food taxes would have greatest benefits to health, labour, and work outcomes; household expenditure; environmental sustainability; and inequalities within the UK food system. Work package 1 includes a rapid review and workshops, aiming to explore the effects of price increases in food and non-alcoholic beverages to facilitate the specification of food taxes and research design. METHODS: In this mixed-methods study, we first did a rapid review to examine relevant published evidence. A preplanned framework ensured a systematic approach, in which we searched PubMed, HMIC, Scopus, Google, Mintel/Mintel Food and Drink, and Business Source Ultimate for papers published in English from Jan 1, 2010, to Nov 2, 2022. This review was followed by three online workshops (in March, 2023), which used interactive padlets to explore food systems, food taxation policy, tax rationales, and a rapid review infographic. 14 stakeholders from non-governmental organisations (n=10), academia (n=2), the Civil Service (n=1), and a local authority (n=1) took part (gender or ethnicity were not recorded). A stakeholder recruitment grid was developed to ensure representation across public sectors and disciplines of public health, nutrition, environment, and economics. FINDINGS: The rapid review identified six tax options with a broadly positive impact on consumption and health (high fat, high sugar, high salt, "junk food", sugar-sweetened-beverages, and meats plus sugar-sweetened beverages). It generated five core rationales for a food tax: change consumption, reduce or prevent harm, change product affordability, raise revenue, and industry impact. Using the workshop feedback, health inequalities, economics, ease of implementation and animal welfare were additional key areas for a so-called real-world application of tax. Stakeholders questioned the taxes in the current economic and political climate. INTERPRETATION: The work highlights the need to develop an impactful food tax option that encompasses the five core rationales identified in the findings. The workshops identified key areas to explore further to understand the feasibility, impact, and logistics of implementing future food taxes. Being unable to deliver workshops in person due to difficulties of participants travelling to London was a limitation. However, switching online allowed for varied and well attended workshops. FUNDING: National Institute of Health Research (Ref: NIHR133927).

Estimation of HbA1c after weight loss using a beta-regression for an economic evaluation of a behavioural weight management programme from the GLoW trial: a methodological study.

BACKGROUND: In economic evaluations, average intervention effects are usually applied to a population. However, this fails to reflect the change in the distribution of HbA1c due to heterogeneous responses to weight loss. We aimed to investigate whether allowing heterogeneous treatment effects using a beta regression better represented the distribution of HbA1c after a weight-loss intervention, and how this affected cost effectiveness. METHODS: The Glucose Lowering through Weight Management (GLoW) trial evaluated the effectiveness of a diabetes education and weight-loss intervention against a standard diabetes education programme. Adults diagnosed with type 2 diabetes within 3 years were recruited from Clinical Commissioning Groups across 159 sites in England from July 20, 2018, to July 22, 2018. Ethics approval (18/ES/0048) and participant informed consent were obtained. Considering the between-treatment-arm difference in HbA1c after 12 months, we compared a mean-effect estimated from a mixed-effects regression to a heterogeneous effect estimated from a beta regression performed on 12-month HbA1c conditional on baseline HbA1c, gender, diabetes duration and intervention group. We used the School of Public Health Research (SPHR) Diabetes Treatment model to apply these treatment effects and evaluate the lifetime NHS costs and quality-adjusted life-years (QALYs), discounted at 3·5%. The microsimulation model estimated diabetes-related health outcomes using the UK Prospective Diabetes Study Outcomes Model 2 risk equations and risk factor trajectory equations, alongside estimating diabetes remission, osteoarthritis, and cancer. We calculated the incremental net benefit (INB) of the intervention using a £20 000 per QALY valuation, by deterministic analysis. The GLoW trial is registered with the ISRCTN Registry, ISRCTN18399564. FINDINGS: The trial recruited 577 participants (mean age 60 years; 278 [53%] female, 247 [47%] male; 474 [91%] white ethnic background). Applying heterogeneous HbA1c changes better reproduced the skewness in post-intervention HbA1c than applying a mean-effect (Kolmogorov-Smirnov test p=0·02 compared with p=0·0000007). The beta-regression method suggested the intervention was more cost-effective, estimating an INB of £736 per person, compared with £584 when applying the mean-effect. INTERPRETATION: Alternative regression specification methods should be considered when evaluating the cost-effectiveness of interventions if the key intervention outcomes are not normally distributed. However, this alternative method requires further investigation to conclude its appropriateness in evaluating cost-effectiveness in different contexts. FUNDING: National Institute for Health and Care Research (NIHR) Programme Grants for Applied Research Programme (Reference Number RP-PG0216-20010).

Understanding the use of media analysis in public health research through food tax debates (HEALTHEI Project): a scoping review.

BACKGROUND: Poor diet is a major public health concern. In 2021, 63·8% of adults and 22·2% of reception-age children were either overweight or obese in England. Fiscal interventions have become a popular policy measure to reduce obesity and encourage healthy eating. Such measures are highly controversial, leading to media debate promoting pro-tax and anti-tax arguments. To better understand food tax debates and the use of media analysis in public health research, we conducted a scoping review of media analyses using food taxes as a case study. METHODS: In this scoping review, we searched SCOPUS, PubMed, and EBSCOhost databases on Feb 14-22, 2023, using keyword variations for "food", "tax", and "media analysis". Results were restricted to English-only, peer-reviewed journal articles. The initial results were manually screened through an iterative process to exclude articles that did not analyse a food tax, were non-English language, were not peer-reviewed, or did not use media analysis as the primary method. Modelled on Arksey and O'Malley's (2005) five-stage review protocol, two researchers used a coding framework to independently code all articles and checked result quality through regular discussion. Extracted data included article title, author, year, country, tax type, media sources used, identified media frames, and research aims, methods, results, and conclusions. Results are reported according to PRISMA guidelines and data files submitted to FigShare Repository (non-accessible). FINDINGS: Of 1087 articles reviewed, 19 were eligible to be included in the study. Articles were published between 2013 and 2023, with 2021 having the highest concentration of studies carried out mainly in UK and USA. Despite search terms encompassing a range of food products, the retrieved media analyses focused on three types of food product taxes: sugar-sweetened beverages, meat, and groceries. Most articles explored arguments for and against policy implementation, with some investigating stakeholder representation. Results demonstrate that stakeholders' arguments, both positive and negative, are consistent across countries and food products. INTERPRETATION: The consistency of how both pro-tax and anti-tax arguments are presented in the media demonstrates the importance of coordination between stakeholder groups to influence policy adoption. To our knowledge, this is the first study to investigate media analysis across a diverse range of food products. FUNDING: National Institute for Health and Care Research (NIHR).

Does cutting down on your food consumption lead to a net improvement in nutritional intake? A panel data approach using data from the UK Biobank.

BACKGROUND: Food diets are complex and a policy targeting one item of a person's diet does not affect their nutritional intake in a solely additive or subtractive manner. Policies tackling unhealthy diets are more likely to be adopted by governments if there is robust evidence to support them. To evaluate dietary policies, it is important to understand the correlations and interdependencies between food groups, as these can lead to unintended negative consequences. We aimed to see whether reductions in consumption of a particular group is related to a net improvement in nutritional intake, after taking into account patterns of consumption and substitution across food groups. METHODS: Detailed dietary data was collected using a 24-h online dietary assessment from the UK Biobank and Oxford Web Q (n = 185,611). We used panel data fixed effects methods to estimate changes in energy, saturated fat, total sugar, and fibre following a 100gram reduction across 44 food groups. We compare these estimates against the average nutritional value of that food group from the UK National Diet and Nutrition Survey. RESULTS: We find evidence of variation in whether a food is compensated between the main confectionery products. Crisps, savoury snacks, and sugar confectionery are less likely to be compensated, whereas chocolate confectionery, biscuits, and buns/cakes/pastries and pies are compensated. The result is particularly striking for chocolate confectionery which shows that while chocolate confectionery often has a high energy content, eating less chocolate confectionery is not associated with an equal reduction in energy. Instead, we find individuals switch or compensate for their reduction in chocolate confectionery consumption with other high energy food items. CONCLUSIONS: We find that sugar confectionery and crisps and savoury snacks are less likely to result in substitution than chocolate confectionery. This would suggest that food policies aiming to reduce the consumption of these food groups are more likely to result in overall lower consumption of unhealthy foods.

Guidance on the use of complex systems models for economic evaluations of public health interventions.

To help health economic modelers respond to demands for greater use of complex systems models in public health. To propose identifiable features of such models and support researchers to plan public health modeling projects using these models. A working group of experts in complex systems modeling and economic evaluation was brought together to develop and jointly write guidance for the use of complex systems models for health economic analysis. The content of workshops was informed by a scoping review. A public health complex systems model for economic evaluation is defined as a quantitative, dynamic, non-linear model that incorporates feedback and interactions among model elements, in order to capture emergent outcomes and estimate health, economic and potentially other consequences to inform public policies. The guidance covers: when complex systems modeling is needed; principles for designing a complex systems model; and how to choose an appropriate modeling technique. This paper provides a definition to identify and characterize complex systems models for economic evaluations and proposes guidance on key aspects of the process for health economics analysis. This document will support the development of complex systems models, with impact on public health systems policy and decision making.

Dietary Approaches to the Management Of type 2 Diabetes (DIAMOND) in primary care: A protocol for a cluster randomised trial.

INTRODUCTION: There is strong evidence that type 2 diabetes (T2D) remission can be achieved by adopting a low-energy diet achieved through total dietary replacement products. There is promising evidence that low-carbohydrate diets can achieve remission of T2D. The Dietary Approaches to the Management of type 2 Diabetes (DIAMOND) programme combines both approaches in a behaviourally informed low-energy, low-carbohydrate diet for people with T2D, delivered by nurses in primary care. This trial compares the effectiveness of the DIAMOND programme to usual care in inducing remission of T2D and in reducing risk of cardiovascular disease. METHODS AND ANALYSIS: We aim to recruit 508 people in 56 practices with T2D diagnosed within 6 years, who are demographically representative of the UK population. We will allocate general practices, based on ethnicity and socioeconomic status, to provide usual care for diabetes or offer the DIAMOND programme. Participants in practices offering DIAMOND will see the nurse seven times over 6 months. At baseline, 6 months, and 1 year we will measure weight, blood pressure, HbA1c, lipid profile and risk of fatty liver disease. The primary outcome is diabetes remission at 1 year, defined as HbA1c < 48 mmol/mol and off glucose-lowering medication for at least 6 months. Thereafter, we will assess whether people resume treatment for diabetes and the incidence of microvascular and macrovascular disease through the National Diabetes Audit. Data will be analysed using mixed-effects generalised linear models. This study has been approved by the National Health Service Health Research Authority Research Ethics Committee (Ref: 22/EM/0074). TRIAL REGISTRATION NUMBER: ISRCTN46961767.

Effectiveness and cost-effectiveness of referral to a commercial open group behavioural weight management programme in adults with overweight and obesity: 5-year follow-up of the WRAP randomised controlled trial.

BACKGROUND: There is evidence that commercially available behavioural weight management programmes can lead to short-term weight loss and reductions in glycaemia. Here, we aimed to provide the 5-year impact and cost-effectiveness of these interventions compared with a brief intervention. METHODS: WRAP was a non-blinded, parallel-group randomised controlled trial (RCT). We recruited from primary care practices in England and randomly assigned participants to one of three interventions (brief intervention, 12-week open-group behavioural programme [WW, formerly Weight Watchers], or a 52-week open-group WW behavioural programme) in an uneven (2:5:5) allocation. Participants were followed up 5 years after randomisation using data from measurement visits at primary care practices or a research centre, review of primary care electronic medical notes, and self-report questionnaires. The primary outcome was change in weight at 5 years follow-up, assessed using analysis of covariance. We also estimated cost-effectiveness of the intervention. This study is registered at Current Controlled Trials, ISRCTN64986150. FINDINGS: Between Oct 18, 2012, and Feb 10, 2014, we recruited 1269 eligible participants (two participants were randomly assigned but not eligible and therefore excluded) and 1040 (82%) consented to be approached about additional follow-up and to have their medical notes reviewed at 5 years. The primary outcome (weight) was ascertained for 871 (69%) of 1267 eligible participants. Mean duration of follow-up was 5·1 (SD 0·3) years. Mean weight change from baseline to 5 years was -0·46 (SD 8·31) kg in the brief intervention group, -1·95 (9·55) kg in the 12-week programme group, and -2·67 (9·81) kg in the 52-week programme. The adjusted difference in weight change was -1·76 (95% CI -3·68 to 0·17) kg between the 52-week programme and the brief intervention; -0·80 (-2·13 to 0·54) kg between the 52-week and the 12-week programme; and -0·96 (-2·90 to 0·97) kg between the 12-week programme and the brief intervention. During the trial, the 12-week programme incurred the lowest cost and produced the highest quality-adjusted life-years (QALY). Simulations beyond 5 years suggested that the 52-week programme would deliver the highest QALYs at the lowest cost and would be the most cost-effective. No participants reported adverse events related to the intervention. INTERPRETATION: Although the difference in weight change between groups was not statistically significant, some weight loss was maintained at 5 years after an open-group behavioural weight management programme. Health economic modelling suggests that this could have important implications to reduce the incidence of weight-related disease and these interventions might be cost-saving. FUNDING: The UK National Institute for Health and Care Research Programme Grants for Applied Research and the Medical Research Council.

BMI trajectories, morbidity, and mortality in England: a two-step approach to estimating consequences of changes in BMI.

OBJECTIVE: BMI is known to have an association with morbidities and mortality. Many studies have argued that identifying health risks using single BMI measures has limitations, particularly in older adults, and that changes in BMI can help to identify risks. This study identifies distinct BMI trajectories and their association with the risks of a range of morbidities and mortality. METHODS: The English Longitudinal Study of Aging provides data on BMI, mortality, and morbidities between 1998 and 2015, sampled from adults over 50 years of age. This study uses a growth-mixture model and discrete-time survival analysis, combined using a two-step approach, which is novel in this setting, to the authors' knowledge. RESULTS: This study identified four trajectories: "stable overweight," "elevated BMI," "increasing BMI," and "decreasing BMI." No differences in mortality, cancer, or stroke risk were found between these trajectories. BMI trajectories were significantly associated with the risks of diabetes, asthma, arthritis, and heart problems. CONCLUSIONS: These results emphasize the importance of looking at change in BMI alongside most recent BMI; BMI trajectories should be considered where possible when assessing health risks. The results suggest that established BMI thresholds should not be used in isolation to identify health risks, particularly in older adults.

The health, cost and equity impacts of restrictions on the advertisement of high fat, salt and sugar products across the transport for London network: a health economic modelling study.

BACKGROUND: Policies aimed at restricting the marketing of high fat, salt and sugar products have been proposed as one way of improving population diet and reducing obesity. In 2019, Transport for London implemented advertising restrictions on high fat, salt and sugar products. A controlled interrupted time-series analysis comparing London with a north of England control, suggested that the advertising restrictions had resulted in a reduction in household energy purchases. The aim of the study presented here was to estimate the health benefits, cost savings and equity impacts of the Transport for London policy using a health economic modelling approach, from an English National Health Service and personal social services perspective. METHODS: A diabetes prevention microsimulation model was modified to incorporate the London population and Transport for London advertising intervention. Conversion of calorie to body mass index reduction was mediated through an approximation of a mathematical model estimating weight loss. Outcomes gathered included incremental obesity, long-term diabetes and cardiovascular disease events, quality-adjusted life years, healthcare costs saved and net monetary benefit. Slope index of inequality was calculated for proportion of people with obesity across socioeconomic groups to assess equity impacts. RESULTS: The results show that the Transport for London policy was estimated to have resulted in 94,867 (4.8%) fewer individuals with obesity, and to reduce incidence of diabetes and cardiovascular disease by 2,857 and 1,915 cases respectively within three years post intervention. The policy would produce an estimated 16,394 additional quality-adjusted life-years and save £218 m in NHS and social care costs over the lifetime of the current population. Greater benefits (e.g. a 37% higher gain in quality-adjusted life-years) were expected to accrue to individuals from the most socioeconomically deprived groups compared to the least deprived. CONCLUSIONS: This analysis suggests that there are considerable potential health and economic gains from restricting the advertisement of high fat, salt and sugar products. The population health and economic impacts of the Transport for London advertising restrictions are likely to have reduced health inequalities in London.

Estimating the impact of changes in weight and BMI on EQ-5D-3L: a longitudinal analysis of a behavioural group-based weight loss intervention.

PURPOSE: To estimate the association between changes in BMI and changes in Health-Related Quality of Life (EQ-5D-3L). METHODS: The WRAP trial was a multicentre, randomised controlled trial with parallel design and recruited 1267 adults (BMI ≥ 28 kg/m2). Participants were allocated to Brief Intervention, a Commercial weight management Programme (WW, formerly Weight Watchers) for 12 weeks, or the same Programme for 52 weeks. Participants were assessed at 0, 3, 12, 24, and 60 months. We analysed the relationship between BMI and EQ-5D-3L, adjusting for age and comorbidities, using a fixed effects model. Test for attrition, model specification and missing data were conducted. Secondary analyses investigated a non-symmetric gradient for weight loss vs. regain. RESULTS: A unit increase in BMI was associated with a - 0.011 (95% CI - 0.01546, - 0.00877) change in EQ-5D-3L. A unit change in BMI between periods of observation was associated with - 0.016 017 (95% CI - 0.0077009, - 0.025086) change in EQ-5D-3L. The negative association was reduced during weight loss, as opposed to weight gain, but the difference was not statistically significant. CONCLUSIONS: We have identified a strong and statistically significant negative relationship between BMI changes and HRQoL. These estimates could be used in economic evaluations of weight loss interventions to inform policymaking. CLINICAL TRIAL REGISTRATION: This trial was registered with Current Controlled Trials, number ISRCTN82857232.

Using health economic modelling to inform the design and development of an intervention: estimating the justifiable cost of weight loss maintenance in the UK.

BACKGROUND: There is a need to develop cost-effective weight loss maintenance interventions to prolong the positive impact of weight loss on health outcomes. Conducting pre-trial health economic modelling is recommended to inform the design and development of behavioural interventions. We aimed to use health economic modelling to estimate the maximum cost per-person (justifiable cost) of a cost-effective behavioural weight loss maintenance intervention, given an estimated intervention effect for individuals with: i) a Body Mass Index (BMI) of 28 kg/m2 or above without diabetes and ii) a diagnosis of type 2 diabetes prescribed a single non-insulin diabetes medication. METHODS: The School for Public Health Research Diabetes prevention model was used to estimate the lifetime Quality-adjusted life year (QALY) gains, healthcare costs, and maximum justifiable cost associated with a weight loss maintenance intervention. Based on a meta-analysis, the estimated effect of a weight loss maintenance intervention following a 9 kg weight loss, was a regain of 1.33 kg and 4.38 kg in years one and two respectively compared to greater regain of 2.84 kg and 5.6 kg in the control group. Sensitivity analysis was conducted around the rate of regain, duration of effect and initial weight loss. RESULTS: The justifiable cost for a weight loss maintenance intervention at an ICER of £20,000 per QALY was £104.64 for an individual with a BMI of 28 or over and £88.14 for an individual with type 2 diabetes. Within sensitivity analysis, this varied from £36.42 to £203.77 for the former, and between £29.98 and £173.05 for the latter. CONCLUSIONS: Researchers developing a weight loss maintenance intervention should consider these maximum justifiable cost estimates and the potential impact of the duration of effect and initial weight loss when designing intervention content and deciding target populations. Future research should consider using the methods demonstrated in this study to use health economic modelling to inform the design and budgetary decisions in the development of a behavioural interventions.

Development of a Web-Based, Guided Self-help, Acceptance and Commitment Therapy-Based Intervention for Weight Loss Maintenance: Evidence-, Theory-, and Person-Based Approach.

BACKGROUND: The long-term impact and cost-effectiveness of weight management programs depend on posttreatment weight maintenance. There is growing evidence that interventions based on third-wave cognitive behavioral therapy, particularly acceptance and commitment therapy (ACT), could improve long-term weight management; however, these interventions are typically delivered face-to-face by psychologists, which limits the scalability of these types of intervention. OBJECTIVE: The aim of this study is to use an evidence-, theory-, and person-based approach to develop an ACT-based intervention for weight loss maintenance that uses digital technology and nonspecialist guidance to minimize the resources needed for delivery at scale. METHODS: Intervention development was guided by the Medical Research Council framework for the development of complex interventions in health care, Intervention Mapping Protocol, and a person-based approach for enhancing the acceptability and feasibility of interventions. Work was conducted in two phases: phase 1 consisted of collating and analyzing existing and new primary evidence and phase 2 consisted of theoretical modeling and intervention development. Phase 1 included a synthesis of existing evidence on weight loss maintenance from previous research, a systematic review and network meta-analysis of third-wave cognitive behavioral therapy interventions for weight management, a qualitative interview study of experiences of weight loss maintenance, and the modeling of a justifiable cost for a weight loss maintenance program. Phase 2 included the iterative development of guiding principles, a logic model, and the intervention design and content. Target user and stakeholder panels were established to inform each phase of development, and user testing of successive iterations of the prototype intervention was conducted. RESULTS: This process resulted in a guided self-help ACT-based intervention called SWiM (Supporting Weight Management). SWiM is a 4-month program consisting of weekly web-based sessions for 13 consecutive weeks followed by a 4-week break for participants to reflect and practice their new skills and a final session at week 18. Each session consists of psychoeducational content, reflective exercises, and behavioral experiments. SWiM includes specific sessions on key determinants of weight loss maintenance, including developing skills to manage high-risk situations for lapses, creating new helpful habits, breaking old unhelpful habits, and learning to manage interpersonal relationships and their impact on weight management. A trained, nonspecialist coach provides guidance for the participants through the program with 4 scheduled 30-minute telephone calls and 3 further optional calls. CONCLUSIONS: This comprehensive approach facilitated the development of an intervention that is based on scientific theory and evidence for supporting people with weight loss maintenance and is grounded in the experiences of the target users and the context in which it is intended to be delivered. The intervention will be refined based on the findings of a planned pilot randomized controlled trial.

A comparison between parent and grandparent dietary provision, feeding styles and feeding practices when caring for preschool-aged children.

Grandparents are frequently called upon to provide childcare to young children. Consequently, grandparents may influence the development of children's eating habits and preferences and may require support with their approach to feeding young children. However, research into grandparental feeding behaviours is scarce. Understanding how grandparental feeding behaviours compare to parental feeding behaviours will further help to establish whether grandparents require specific interventions unique to the grandparental role or if current strategies that target parental feeding behaviour are also appropriate for grandparents. The aim of the present study was to explore the similarities and differences between parent and grandparent dietary provision, feeding practices and feeding styles to preschool-aged children. 72 parents and 44 unrelated grandparents of children aged 2-4 years old took part in an online study and completed an online 24-h dietary recall using myfood24® to assess dietary provision. Parents and grandparents were providing meals high in saturated fat and sodium and providing below recommended amounts of fruit and vegetables. Overall, feeding practices were similar between parents and grandparents. Although, grandparents scored lower on using food as a reward (p < 0.05) and creating a healthy food environment (p < 0.05) compared to parents. Whereas, parents scored higher for promoting balance and variety (p < 0.05). A range of feeding styles were found within each caregiver type, with no significant associations found between caregiver type and feeding style (p > 0.05). Strategies to promote healthy eating in young children should be expanded to also target grandparents who act as informal caregivers to preschool-aged children. However, since very few differences in feeding behaviour were reported the content of such strategies may not need to be adapted specifically for grandparents.

Mechanisms of Action in a Behavioral Weight-Management Program: Latent Growth Curve Analysis.

BACKGROUND: A greater understanding of the mechanisms of action of weight-management interventions is needed to inform the design of effective interventions. PURPOSE: To investigate whether dietary restraint, habit strength, or diet self-regulation mediated the impact of a behavioral weight-management intervention on weight loss and weight loss maintenance. METHODS: Latent growth curve analysis (LGCA) was conducted on trial data in which adults (N = 1,267) with a body mass index (BMI) ≥28 kg/m2 were randomized to either a brief intervention (booklet on losing weight), a 12 week weight-management program or the same program for 52 weeks. LGCA estimated the trajectory of the variables over four time points (baseline and 3, 12 and 24 months) to assess whether potential mechanisms of action mediated the impact of the weight-management program on BMI. RESULTS: Participants randomized to the 12 and 52 week programs had a significantly greater decrease in BMI than the brief intervention. This direct effect became nonsignificant when dietary restraint, habit strength, and autonomous diet self-regulation were controlled for. The total indirect effect was significant for both the 12 (estimate = -1.33, standard error [SE] = 0.41, p = .001) and 52 week (estimate = -2.13, SE = 0.52, p < .001) program. Only the individual indirect effect for dietary restraint was significant for the 12 week intervention, whereas all three indirect effects were significant for the 52 week intervention. CONCLUSIONS: Behavior change techniques that target dietary restraint, habit strength, and autonomous diet self-regulation should be considered when designing weight loss and weight loss maintenance interventions. Longer interventions may need to target both deliberative and automatic control processes to support successful weight management.

Examination of dietary intake of UK preschool children by varying carers: evidence from the 2008-2016 UK National Diet and Nutrition Survey.

Early years caregivers can play a key role in young children's eating and the prevention of childhood obesity. The UK National Diet and Nutrition Survey (NDNS) is a large representative survey collecting detailed food and nutrition consumption data. Using these data, the aim of this study was to investigate the relationship between dietary intake of preschool children in the UK aged 2 to 4 years and accompanying adult/s. Nutrition consumption data from 1218 preschool children from years 1 to 8 of the 2008-2016 NDNS were accessed. Dietary data were captured using 3 or 4 day estimated food diaries. Regression analyses revealed significant differences in consumption when children were not accompanied by their parents. Compared with when children were with parents, children consumed significantly more energy dense meals (0·32 kJ/g, 95% CI 0·1-0·6 kJ/g), energy (62 kJ/g, (95% CI 27-97 kJ)) Na (19 mg, (95 % CI 6, 32)), added sugars (0·6 g, (95 % CI 0·1, 1·1)), vegetables (3 g, (95 % CI 1, 4)), total grams (12 g, (95 % CI 3, 21)) and saturated fat (0·2 g, (95 % CI 0·1, 0·4)) per eating occasion when accompanied by wider family. When children were accompanied by a formal childcare provider, they consumed significantly lower energy dense meals (-0·9 kJ/g, (95% CI -1·4 - -0·3 kJ/g)), less added sugars (-1·6 g, (95 % CI -2·4, -0·8)) and more fruit (12 g, (95 % CI 3, 21)) per eating occasion than when they were with their parents. The results demonstrate that non-parental caregivers might be an important target to promote healthy eating in young children. Further research is needed to establish which caregivers would benefit most.

Grandparental dietary provision, feeding practices and feeding styles when caring for preschool-aged grandchildren: A systematic mixed methods review.

Grandparents are frequently relied upon to care for their preschool-aged grandchildren. These early years are a crucial age in the development of dietary habits and preferences. This review aims to determine grandparental dietary provision, feeding practices and feeding styles when caring for their preschool-aged grandchildren. Medline, PsycInfo and Web of Science were searched in January 2020. A systematic mixed methods approach was used to synthesize the qualitative (n = 13) and quantitative (n = 7) articles describing grandparents' feeding styles (n = 9), feeding practices (n = 14) and dietary provision (n = 18). Grandparents are serving large portion sizes and encouraging their grandchildren to eat frequently. Results are mixed for the types of foods provided; grandparents provide discretionary foods high in sugar and fat, and some also choose more expensive core foods as treats (e.g., berries). Grandparents engage in feeding practices that promote healthy eating (e.g., creating a healthy feeding environment) and promote autonomy and independence (e.g., considering their grandchild's preferences). However, they also use some coercive feeding practices (e.g., using food as a reward) and may be using indulgent feeding styles, which can be conducive to obesogenic dietary intakes. Interventions targeting grandparents could be an effective way to improve dietary-related health outcomes in young children.

What are the cost-savings and health benefits of improving detection and management for six high cardiovascular risk conditions in England? An economic evaluation.

OBJECTIVES: To estimate the cost savings and health benefits of improving detection of individuals at high risk of cardiovascular disease (CVD) in England, to determine to which patient subgroups these benefits arise, and to compare different strategies for subsequent management. DESIGN: An economic analysis using the School for Public Health Research CVD Prevention Model. SETTING: England 2018. PARTICIPANTS: Adults aged 16 and older with one or more high cardiovascular risk conditions, including hypertension, diabetes, non-diabetic hyperglycaemia, atrial fibrillation, chronic kidney disease and high cholesterol. INTERVENTIONS: Detection of 100% of individuals with CVD high risk conditions compared with current levels of detection in England. Detected individuals are assumed to be managed either according to current levels of care or National Institute of Health and Care Excellence (NICE) guidelines. MAIN OUTCOME MEASURES: Incremental and cumulative costs, savings, quality adjusted life years (QALYs), CVD cases, and net monetary benefit, from a UK NHS and Personal Social Services perspective. RESULTS: £68 billion could be saved, 4.9 million QALYs gained and 3.4 million cases of CVD prevented over 25 years if all individuals in England with the six CVD high risk conditions were diagnosed and subsequently managed at current levels. Additionally, if all detected individuals were managed according to NICE guidelines, total savings would be £61 billion, 8.1 million QALYs would be gained and 5.2 million CVD cases prevented. Most benefits come from detection of high cholesterol in the short term and diabetes in the long term. CONCLUSIONS: Substantial cost savings and health benefits would accrue if all individuals with conditions that increase CVD risk could be diagnosed, with detection of undiagnosed diabetes producing greatest benefits. Ensuring all conditions are managed according to NICE guidelines would further increase health benefits. Projected cost-savings could be invested in developing acceptable and cost-effective solutions for improving detection and management.

The Impact of Including Costs and Outcomes of Dementia in a Health Economic Model to Evaluate Lifestyle Interventions to Prevent Diabetes and Cardiovascular Disease.

OBJECTIVES: Economic evaluations of lifestyle interventions, which aim to prevent diabetes/cardiovascular disease (CVD), have not included dementia. Lifestyle interventions decrease dementia risk and extend life expectancy, leading to competing effects on health care costs. We aim to demonstrate the feasibility of including dementia in a public health cost-effectiveness analysis and quantify the overall impacts accounting for these competing effects. METHODS: The School for Public Health Research (SPHR) diabetes prevention model describes individuals' risk of type 2 diabetes, microvascular outcomes, CVD, congestive heart failure, cancer, osteoarthritis, depression, and mortality in England. In version 3.1, we adapted the model to include dementia using published data from primary care databases, health surveys, and trials of dementia to describe dementia incidence, diagnosis, and disease progression. We estimate the impact of dementia on lifetime costs and quality-adjusted life years (QALYs) gained of the National Health Service diabetes prevention program (NHS DPP) from an NHS/personal social services perspective with 3 scenarios: 1) no dementia, 2) dementia only, and 3) reduced dementia risk. Subgroup, parameter, and probabilistic sensitivity analyses were conducted. RESULTS: The lifetime cost savings of the NHS DPP per patient were £145 in the no-dementia scenario, £121 in the dementia-only scenario, and £167 in the reduced dementia risk scenario. The QALY gains increased by 0.0006 in dementia only and 0.0134 in reduced dementia risk. Dementia did not alter the recommendation that the NHS/DPP is cost-effective. CONCLUSIONS: Including dementia into a model of lifestyle interventions was feasible but did not change policy recommendations or modify health economic outcomes. The impact on health economic outcomes was largest where a direct impact on dementia incidence was assumed, particularly in elderly populations.