Utility values for childhood obesity interventions: a systematic review and meta-analysis of the evidence for use in economic evaluation

Insights from a codesigned dynamic modelling study of child and adolescent obesity in Australia

Introduction

Child and adolescent obesity is associated with a range of immediate health issues and influences obesity in adulthood. The complex nature of health determinants that contribute to obesity makes it challenging to deliver effective public health interventions. This research presents insights from a system dynamics model of childhood and adolescent obesity aimed at supporting evidence-based decision-making.

Methods

A system dynamics model was developed using the best available evidence and data, with input from research and industry experts to map the hypothetical causal structure of the factors contributing to childhood and adolescent obesity in Australia. The model was calibrated to fit the historical prevalence of obesity (R 2 =0.97, mean squared error (MSE)=4.94E-04). Intervention-based scenarios were simulated to examine how changes in environmental factors and health-related behaviours may affect the prevalence of obesity. The potential economic benefits of the scenarios were estimated from changes in population healthcare spending and quality of life compared with base model projections.

Results

A series of interventions were explored in the model, including changes in early childhood behaviours, changes to diet and physical activity in childcare and school settings, financial support for organised sports and sugar-sweetened beverage taxation. The most promising individually implemented intervention scenario for reducing the prevalence of childhood and adolescent obesity was a sugar-sweetened beverage tax (0.57 percentage points and 0.61 percentage points, respectively) and government funding of organised sports (0.42 percentage points and 0.63 percentage points, respectively). When all interventions were implemented in combination, childhood obesity was reduced by 1.43 percentage points and 1.81 percentage points in adolescents.

Conclusions

The findings highlight the challenges faced by policy-makers and public health practitioners working to reduce childhood and adolescent obesity. Insights from the model emphasise the value of public health programmes over the life course. Implementing initiatives with broad reach that support healthy choices may reduce obesity, resulting in a healthier Australian population.

Impact of the UK soft drinks industry levy on health and health inequalities in children and adolescents in England: An interrupted time series analysis and population health modelling study

BACKGROUND

The soft drinks industry levy (SDIL) in the United Kingdom has led to a significant reduction in household purchasing of sugar in drinks. In this study, we examined the potential medium- and long-term implications for health and health inequalities among children and adolescents in England.

METHODS AND FINDINGS

We conducted a controlled interrupted time series analysis to measure the effects of the SDIL on the amount of sugar per household per week from soft drinks purchased, 19 months post implementation and by index of multiple deprivation (IMD) quintile in England. We modelled the effect of observed sugar reduction on body mass index (BMI), dental caries, and quality-adjusted life years (QALYs) in children and adolescents (0 to 17 years) by IMD quintile over the first 10 years following announcement (March 2016) and implementation (April 2018) of the SDIL. Using a lifetable model, we simulated the potential long-term impact of these changes on life expectancy for the current birth cohort and, using regression models with results from the IMD-specific lifetable models, we calculated the impact of the SDIL on the slope index of inequality (SII) in life expectancy. The SDIL was found to have reduced sugar from purchased drinks in England by 15 g/household/week (95% confidence interval: -10.3 to -19.7). The model predicts these reductions in sugar will lead to 3,600 (95% uncertainty interval: 946 to 6,330) fewer dental caries and 64,100 (54,400 to 73,400) fewer children and adolescents classified as overweight or obese, in the first 10 years after implementation. The changes in sugar purchasing and predicted impacts on health are largest for children and adolescents in the most deprived areas (Q1: 11,000 QALYs [8,370 to 14,100] and Q2: 7,760 QALYs [5,730 to 9,970]), while children and adolescents in less deprived areas will likely experience much smaller simulated effects (Q3: -1,830 QALYs [-3,260 to -501], Q4: 652 QALYs [-336 to 1,680], Q5: 1,860 QALYs [929 to 2,890]). If the simulated effects of the SDIL are sustained over the life course, it is predicted there will be a small but significant reduction in slope index of inequality: 0.76% (95% uncertainty interval: -0.9 to -0.62) for females and 0.94% (-1.1 to -0.76) for males.

CONCLUSIONS

We predict that the SDIL will lead to medium-term reductions in dental caries and overweight/obesity, and long-term improvements in life expectancy, with the greatest benefits projected for children and adolescents from more deprived areas. This study provides evidence that the SDIL could narrow health inequalities for children and adolescents in England.

Cost-effectiveness of reducing children's sedentary time and increasing physical activity at school: the Transform-Us! intervention

BACKGROUND

Improving physical activity and reducing sedentary behavior represent important areas for intervention in childhood in order to reduce the burden of chronic disease related to obesity and physical inactivity in later life. This paper aims to determine the cost-effectiveness of a multi-arm primary school-based intervention to increase physical activity and/or reduce sedentary time in 8-9 year old children (Transform-Us!).

METHODS

Modelled cost-utility analysis, using costs and effects from a cluster randomized controlled trial of a 30-month intervention that used pedagogical and environmental strategies to reduce and break up sedentary behaviour (SB-I), promote physical activity (PA-I), or a combined approach (PA + SB-I), compared to current practice. A validated multiple-cohort lifetable model (ACE-Obesity Policy model) estimated the obesity and physical activity-related health outcomes (measured as change in body mass index and change in metabolic equivalent task minutes respectively) and healthcare cost-savings over the cohort's lifetime from the public-payer perspective, assuming the intervention was delivered to all 8-9 year old children attending Australian Government primary schools. Sensitivity analyses tested the impact on cost-effectiveness of varying key input parameters, including maintenance of intervention effect assumptions.

RESULTS

Cost-effectiveness results demonstrated that, when compared to control schools, the PA-I and SB-I intervention arms were "dominant", meaning that they resulted in net health benefits and healthcare cost-savings if the intervention effects were maintained. When the costs and effects of these intervention arms were extrapolated to the Australian population, results suggested significant potential as obesity prevention measures (PA-I: 60,780 HALYs saved (95% UI 15,007-109,413), healthcare cost-savings AUD641M (95% UI AUD165M-$1.1B); SB-I: 61,126 HALYs saved (95% UI 11,770 - 111,249), healthcare cost-savings AUD654M (95% UI AUD126M-1.2B)). The PA-I and SB-I interventions remained cost-effective in sensitivity analysis, assuming the full decay of intervention effect after 10 years.

CONCLUSIONS

The PA-I and SB-I Transform-Us! intervention arms represent good value for money and could lead to health benefits and healthcare cost-savings arising from the prevention of chronic disease in later life if intervention effects are sustained.

TRIAL REGISTRATION

International Standard Randomized Controlled Trial Number (ISRCTN83725066). Australia and New Zealand Clinical Trials Registry Number (ACTRN12609000715279).

A comparative analysis of the cost-utility of the Philippine tax on sweetened beverages as proposed and as implemented

Background

In response to increasing overweight and obesity, the Philippine government introduced a tax on sweetened beverages (SBs) in 2018. Evidence suggests that the beverage industry influenced the final tax design, making it more favourable for industry than the initially proposed bill. This study aimed to compare the relative health and economic benefits of the proposed SB tax with the implemented SB tax.

Methods

Philippine dietary consumption data were combined with price elasticity data from Mexico and data from Australia adapted to the Philippine context to estimate reductions in SB purchases and changes in body mass index (BMI) following the implementation of the tax. A multi-state, multiple-cohort Markov model was used to estimate the change in health-adjusted life years (HALYs) due to reduction in the epidemiology of obesity-related diseases, healthcare cost savings and government taxation revenue, resulting from both the proposed and implemented tax policies, over the lifetime of the 2018 Philippine population.

Findings

The proposed and implemented taxes were modelled to be dominant (cost-saving and improving health). Intervention costs were modelled to be PHP305.2 million (M) (approximately US$6M). Compared to the proposed tax, the implemented tax was modelled to result in a 43.0% smaller reduction in targeted beverage intake (51.1 ml/person/day vs. 89.7 ml/person/day), a 43.5% smaller reduction in BMI (0.35 kg/m2 vs. 0.62 kg/m2), 39.7% fewer HALYs gained (2,503,118 vs. 4,149,030), 39.9% fewer healthcare cost savings (PHP16.4 billion (B) vs. PHP27.3B), and 27.7% less government taxation revenue (PHP426.3B vs. PHP589.4B).

Interpretation

While the implemented tax in the Philippines will benefit population health, it is likely to yield less benefit than the proposed tax. The influence of the food and beverage industry on policy processes has the potential to lessen the benefits of population NCD prevention policies.

Funding

OH was supported to conduct this research by an Australian Government Research Training Program Stipend Scholarship. The funding body had no role in data collection and analysis, or manuscript preparation.

A systematic review of economic evidence for community-based obesity prevention interventions in children

Multicomponent community-based obesity prevention interventions that engage multiple sectors have shown promise in preventing obesity in childhood; however, economic evaluations of such interventions are limited. This systematic review explores the methods used and summarizes current evidence of costs and cost-effectiveness of complex obesity prevention interventions. A systematic search was conducted using 12 academic databases and grey literature from 2006 to April 2022. Studies were included if they reported methods of costing and/or economic evaluation of multicomponent, multisectoral, and community-wide obesity prevention interventions. Results were reported narratively based on the Consolidated Health Economic Evaluation Reporting Standards. Seventeen studies were included, reporting costing or economic evaluation of 13 different interventions. Five interventions reported full economic evaluations, five interventions reported economic evaluation protocols, two interventions reported cost analysis, and one intervention reported a costing protocol. Five studies conducted cost-utility analysis, three of which were cost-effective. One study reported a cost-saving return-on-investment ratio. The economic evidence for complex obesity prevention interventions is limited and therefore inconclusive. Challenges include accurate tracking of costs for interventions with multiple actors, and the limited incorporation of broader benefits into economic evaluation. Further methodological development is needed to find appropriate pragmatic methods to evaluate complex obesity prevention interventions.

Health state utilities associated with hyperphagia: Data for use in cost-utility models

Objective

Rare genetic diseases of obesity typically present with hyperphagia, a pathologic desire to consume food. Cost-utility models assessing the value of treatments for these rare diseases will require health state utilities representing hyperphagia. This study estimated utilities associated with various hyperphagia severity levels.

Methods

Four health state vignettes were developed using published literature and clinician input to represent various severity levels of hyperphagia. Utilities were estimated for these health states in a time trade-off elicitation study in a UK general population sample.

Results

In total, 215 participants completed interviews (39.5% male; mean age 39.1 years). Mean (SD) utilities were 0.98 (0.02) for no hyperphagia, 0.91 (0.10) for mild hyperphagia, 0.70 (0.30) for moderate hyperphagia, and 0.22 (0.59) for severe hyperphagia. Mean (SD) disutilities were -0.08 (0.10) for mild, -0.28 (0.30) for moderate, and -0.77 (0.58) for severe hyperphagia.

Conclusions

These data show increasing severity of hyperphagia is associated with decreased utility. Utilities associated with severe hyperphagia are similar to those of other health conditions severely impacting quality of life (QoL). These findings highlight that treatments addressing substantial QoL impacts of severe hyperphagia are needed. Utilities estimated here may be useful in cost-utility models of treatments for rare genetic diseases of obesity.

Modelled Distributional Cost-Effectiveness Analysis of Childhood Obesity Interventions: A Demonstration

OBJECTIVE

To demonstrate how distributional cost-effectiveness analyses of childhood obesity interventions could be conducted and presented for decision makers.

METHODS

We conducted modelled distributional cost-effectiveness analyses of three obesity interventions in children: an infant sleep intervention (POI-Sleep), a combined infant sleep, food, activity and breastfeeding intervention (POI-Combo) and a clinician-led treatment for primary school-aged children with overweight and obesity (High Five for Kids). For each intervention, costs and socioeconomic position (SEP)-specific effect sizes were applied to an Australian child cohort (n = 4898). Using a purpose-built microsimulation model we simulated SEP-specific body mass index (BMI) trajectories, healthcare costs and quality-adjusted life years (QALYs) from age 4 to 17 years for control and intervention cohorts. We examined the distribution of each health outcome across SEP and determined the net health benefit and equity impact accounting for opportunity costs and uncertainty due to individual-level heterogeneity. Finally, we conducted scenario analyses to test the effect of assumptions about health system marginal productivity, the distribution of opportunity costs and SEP-specific effect sizes. The results of the primary analyses, uncertainty analyses and scenario analyses were presented on an efficiency-equity impact plane.

RESULTS

Accounting for uncertainty, POI-Sleep and High Five for Kids were found to be 'win-win' interventions, with a 67% and 100% probability, respectively, of generating a net health benefit and positive equity impact compared with control. POI-Combo was found to be a 'lose-lose' intervention, with a 91% probability of producing a net health loss and a negative equity impact compared with control. Scenario analyses indicated that SEP-specific effect sizes were highly influential on equity impact estimates for POI-Combo and High Five for Kids, while health system marginal productivity and opportunity cost distribution assumptions primarily influenced the net health benefit and equity impact of POI-Combo.

CONCLUSIONS

These analyses demonstrated that distributional cost-effectiveness analyses using a fit-for-purpose model are appropriate for differentiating and communicating the efficiency and equity impacts of childhood obesity interventions.

Potential cost-effectiveness of e-health interventions for treating overweight and obesity in Australian adolescents

BACKGROUND

E-health, defined as the use of information and communication technologies to improve healthcare delivery and health outcomes, has been promoted as a cost-effective strategy to treat adolescent overweight and obesity. However, evidence supporting this claim is lacking.

OBJECTIVES

Assess the potential cost-effectiveness of a hypothetical e-health intervention for adolescents with overweight and obesity.

METHODS

The costs and effect size (BMI reduction) of the hypothetical intervention were sourced from recent systematic reviews. Using a micro-simulation model with a lifetime time horizon, we conducted a modelled cost-utility analysis of the intervention compared to a 'do-nothing' approach. To explore uncertainty, we conducted bootstrapping on individual-level costs and quality-adjusted life years (QALYs) and performed multiple one-way sensitivity analyses.

RESULTS

The incremental cost-effectiveness ratio (ICER) for the e-health intervention was dominant (cheaper and more effective), with a 96% probability of being cost-effective at a willingness-to-pay (WTP) of $50 000/QALY. The ICER remained dominant in all sensitivity analyses except when using the lower bounds of the hypothetical intervention effect size, which reduced the probability of cost-effectiveness at a WTP of $50 000/QALY to 51%.

CONCLUSION

E-health interventions for treatment of adolescent overweight and obesity demonstrate very good cost-effectiveness potential and should be considered by healthcare decision makers. However, further research on the efficacy of such interventions is warranted to strengthen the case for investment.

Economic and health impacts of the Change4Life Food Scanner app: Findings from a randomized pilot and feasibility study

Introduction

The UK Government developed the Change4Life Food Scanner app to provide families with engaging feedback on the nutritional content of packaged foods. There is a lack of research exploring the cost-effectiveness of dietary health promotion apps.

Methods

Through stakeholder engagement, a conceptual model was developed, outlining the pathway by which the Food Scanner app leads to proximal and distal outcomes. The conceptual model informed the development of a pilot randomized controlled trial which investigated the feasibility and acceptability of evaluating clinical outcomes in children and economic effectiveness of the Food Scanner app through a cost-consequence analysis. Parents of 4–11 years-olds (n = 126) were randomized into an app exposure condition (n = 62), or no intervention control (n = 64). Parent-reported Child Health Utility 9 Dimension (CHU9D) outcomes were collected alongside child healthcare resource use and associated costs, school absenteeism and parent productivity losses at baseline and 3 months follow up. Results for the CHU9D were converted into utility scores based on UK adult preference weights. Sensitivity analysis accounted for outliers and multiple imputation methods were adopted for the handling of missing data.

Results

64 participants (51%) completed the study (intervention: n = 29; control: n = 35). There was a mean reduction in quality adjusted life years between groups over the trial period of –0.004 (SD = 0.024, 95% CI: –0.005; 0.012). There was a mean reduction in healthcare costs of –£30.77 (SD = 230.97; 95% CI: –£113.80; £52.26) and a mean reduction in workplace productivity losses of –£64.24 (SD = 241.66, 95% CI: –£147.54; £19.07) within the intervention arm, compared to the control arm, over the data collection period. Similar findings were apparent after multiple imputation.

Discussion

Modest mean differences between study arms may have been due to the exploration of distal outcomes over a short follow-up period. The study was also disrupted due to the coronavirus pandemic, which may have confounded healthcare resource data. Although measures adopted were deemed feasible, the study highlighted difficulties in obtaining data on app development and maintenance costs, as well as the importance of economic modeling to predict long-term outcomes that may not be reliably captured over the short-term.

Clinical trial registration

https://osf.io/, identifier 62hzt.

Is the cost-effectiveness of an early-childhood sleep intervention to prevent obesity affected by socioeconomic position?

OBJECTIVE

This study aimed to determine whether the cost-effectiveness of an infant sleep intervention from the Prevention of Overweight in Infancy (POI) trial was influenced by socioeconomic position (SEP).

METHODS

An SEP-specific economic evaluation of the sleep intervention was conducted. SEP-specific intervention costs and effects at age 5 years, derived from the trial data, were applied to a representative cohort of 4,898 4- to 5-year-old Australian children. Quality-adjusted life years and health care costs were simulated until age 17 years using a purpose-built SEP-specific model. Incremental cost-effectiveness ratios and acceptability curves were derived for each SEP group.

RESULTS

The incremental cost-effectiveness ratios, in Australian dollars per quality-adjusted life year gained, were smaller in the low- ($23,010) and mid-SEP ($18,206) groups compared with the high-SEP group ($31,981). The probability that the intervention was cost-effective was very high in the low- and mid-SEP groups (92%-100%) and moderately high in the high-SEP group (79%).

CONCLUSIONS

An infant sleep intervention is more cost-effective in low- and mid-SEP groups compared with high-SEP groups. Targeting this intervention to low-SEP groups would not require trade-offs between efficiency and equity.

Quality appraisal for systematic literature reviews of health state utility values: a descriptive analysis

BACKGROUND

Health state utility values (HSUVs) are an essential input parameter to cost-utility analysis (CUA). Systematic literature reviews (SLRs) provide summarized information for selecting utility values from an increasing number of primary studies eliciting HSUVs. Quality appraisal (QA) of such SLRs is an important process towards the credibility of HSUVs estimates; yet, authors often overlook this crucial process. A scientifically developed and widely accepted QA tool for this purpose is lacking and warranted.

OBJECTIVES

To comprehensively describe the nature of QA in published SRLs of studies eliciting HSUVs and generate a list of commonly used items.

METHODS

A comprehensive literature search was conducted in PubMed and Embase from 01.01.2015 to 15.05.2021. SLRs of empirical studies eliciting HSUVs that were published in English were included. We extracted descriptive data, which included QA tools checklists or good practice recommendations used or cited, items used, and the methods of incorporating QA results into study findings. Descriptive statistics (frequencies of use and occurrences of items, acceptance and counterfactual acceptance rates) were computed and a comprehensive list of QA items was generated.

RESULTS

A total of 73 SLRs were included, comprising 93 items and 35 QA tools and good recommendation practices. The prevalence of QA was 55% (40/73). Recommendations by NICE and ISPOR guidelines appeared in 42% (16/40) of the SLRs that appraised quality. The most commonly used QA items in SLRs were response rates (27/40), statistical analysis (22/40), sample size (21/40) and loss of follow up (21/40). Yet, the most commonly featured items in QA tools and GPRs were statistical analysis (23/35), confounding or baseline equivalency (20/35), and blinding (14/35). Only 5% of the SLRS used QA to inform the data analysis, with acceptance rates of 100% (in two studies) 67%, 53% and 33%. The mean counterfactual acceptance rate was 55% (median 53% and IQR 56%).

CONCLUSIONS

There is a considerably low prevalence of QA in the SLRs of HSUVs. Also, there is a wide variation in the QA dimensions and items included in both SLRs and extracted tools. This underscores the need for a scientifically developed QA tool for multi-variable primary studies of HSUVs.

Methods for the economic evaluation of obesity prevention dietary interventions in children: A systematic review and critical appraisal of the evidence

OBJECTIVES

We aim to describe and provide a discussion of methods used to conduct economic evaluations of dietary interventions in children and adolescents, including long-term modelling, and to make recommendations to assist health economists in the design and reporting of such evaluations.

METHODS

A systematic review was conducted in 11 bibliographic databases and the grey literature with searches undertaken between January 2000 and December 2021. A study was included if it (1) was an economic evaluation or modelling study of an obesity-prevention dietary intervention and (2) targeted 2- to 18-year-olds.

RESULTS

Twenty-six studies met the inclusion criteria. Twelve studies conducted an economic evaluation alongside a clinical trial, and 14 studies modelled long-term health and cost outcomes. Four overarching methodological challenges were identified: modelling long-term impact of interventions, measuring and valuing health outcomes, cost inclusions and equity considerations.

CONCLUSIONS

Variability in methods used to predict, measure and value long-term benefits in adulthood from short-term clinical outcomes in childhood was evident across studies. Key recommendations to improve the design and analysis of future economic evaluations include the consideration of weight regain and diminishing intervention effects within future projections; exploration of wider intervention benefits not restricted to quality-of-life outcomes; and inclusion of parental or caregiver opportunity costs.

Cost-effectiveness of scaling up a whole-of-community intervention: The Romp & Chomp early childhood obesity prevention intervention

BACKGROUND

Given the high prevalence of early childhood overweight and obesity, more evidence is required to better understand the cost-effectiveness of community-wide interventions targeting obesity prevention in children aged 0-5 years.

OBJECTIVES

To assess the cost-effectiveness of the Romp & Chomp community-wide early childhood obesity prevention intervention if delivered across Australia in 2018 from a funder perspective, against a no-intervention comparator.

METHODS

Intervention costs were estimated in 2018 Australian dollars. The annual Early Prevention of Obesity in Childhood micro-simulation model estimated body mass index (BMI) trajectories to age 15 years, based on end of trial data at age 3.5 years. Results from modelled cost-effectiveness analyses were presented as incremental cost-effectiveness ratios (ICERs): cost per BMI unit avoided, and cost per quality-adjusted life year (QALY) gained at age 15 years.

RESULTS

All Australian children aged 0-5 years (n = 1 906 075) would receive the intervention. Total estimated intervention cost and annual cost per participant were AUD178 million and AUD93, respectively, if implemented nationally. The ICERs were AUD1 126 per BMI unit avoided and AUD26 399 per QALY gained (64% probability of being cost-effective measured against a AUD50 000 per QALY threshold).

CONCLUSIONS

Romp & Chomp has a fair probability of being cost-effective if delivered at scale.

A scoping review of outcomes commonly reported in obesity prevention interventions aiming to improve obesity-related health behaviors in children to age 5 years

This scoping review was undertaken as the first stage of development of the Core Outcome Sets for Early Prevention of Obesity in CHildhood (COS-EPOCH). The aim of this review is to identify the outcomes collected and reported in randomized controlled trials of early childhood obesity prevention interventions. A systematic scoping review was undertaken following published guidelines. Trial registries and Medline were searched, and records retrieved were screened by two reviewers. Included trials aimed to prevent childhood obesity in the first 5 years of life and were randomized. Data were extracted using a standardized form. Outcomes were assigned to outcome domains, and similar definitions within each domain were merged, based on key literature and expert consensus. Outcome and domain frequencies were estimated and presented in outcome matrices. Eighteen outcome domains were identified from 161 included studies: "anthropometry," "dietary intake," "physical activity," "sedentary behaviour," "emotional functioning/wellbeing," "feeding," "cognitive/executive functioning," "sleep," "other," "study-related," "parenting practices," "motor skill development," "environmental," "blood and lymphatic system," "perceptions and preferences," "quality of life," and "economic," "oral health." The most frequently reported outcome domain was anthropometry (92% of studies), followed by dietary intake (77%) and physical activity (60%). 221 unique outcomes were identified, indicating a high degree of heterogeneity. Body mass index was the only outcome reported in >50% of studies. The considerable heterogeneity in outcomes supports the need for the development of COS-EPOCH.

Health Economic Aspects of Childhood Excess Weight: A Structured Review

An economic perspective is crucial to understand the broad consequences of childhood excess weight (CEW). These can manifest in the form of elevated health care and societal costs, impaired health status, or inefficiencies in the allocation of resources targeted at its prevention, management, or treatment. Although existing systematic reviews provide summaries of distinct economic research strands covering CEW, they have a restricted focus that overlooks relevant evidence. The overarching aim of this structured review was to update and enhance recent key reviews of four strands of economic evidence in this area, namely, (1) economic costs associated with CEW, (2) health utilities associated with CEW, (3) economic evaluations of interventions targeting CEW, and (4) economic determinants and broader consequences of CEW. Our de novo searches identified six additional studies for the first research strand, five studies for the second, thirty-one for the third, and two for the fourth. Most studies were conducted in a small number of high-income countries. Our review highlights knowledge gaps across all the research strands. Evidence from this structured review can act as data input into future economic evaluations in this area and highlights areas where future economic research should be targeted.

The impact of loneliness and social isolation on health state utility values: a systematic literature review

Background

Loneliness and social isolation are recognised as social problems and denote a significant health burden. The aim of this study was to conduct a systematic literature review to explore the health state utility values (HSUVs) associated with loneliness and/or social isolation.

Method

Peer-reviewed journals published in English language that reported both HSUVs along with loneliness and/or social isolation scores were identified through five databases. No restrictions were made relating to the population, study design or utility estimation method used.

Results

In total, 19 papers were included; 12 included a measure of loneliness, four studies included a measure of social isolation and three studies considered both loneliness and social isolation. All studies focused on individuals with pre-existing health conditions—where the EQ-5D-3L instrument was most frequently used to assess HSUVs. HSUVs ranged from 0.5 to 0.95 in those who reported not being lonely, 0.42 to 0.97 in those who experienced some level of loneliness, 0.3 to 0.87 in those who were socially isolated and 0.63 to 0.94 in those who were not socially isolated.

Conclusion

There was significant variation in HSUVs complicated by the presence of co-morbidities, population heterogeneity, variations in methods used to derive utility scores and differences in the measurement of loneliness and/or social isolation. Nevertheless, the lower HSUVs observed should be considered to significantly impact quality of life, though we also note the need for further research to explore the unique impact of loneliness and social isolation on HSUVs that can be used in the future economic evaluations.

Utility Decrements Associated with Adult Overweight and Obesity in Australia: A Systematic Review and Meta-Analysis

OBJECTIVE

The aim was to conduct a systematic review and meta-analysis of health state utility decrements associated with overweight and obesity in adults 18 years and over, for use in modelled economic evaluations in Australia.

METHODS

A systematic review was conducted in nine databases to identify studies that reported health state utility values by weight status. Random-effects meta-analysis was used to synthesise average utility decrements (from healthy weight) associated with overweight, all obesity and obesity classes 1, 2 and 3. Heterogeneity surrounding utility decrements was assessed via sub-group analysis, random-effects meta-regression and sensitivity analyses.

RESULTS

Twelve studies were found for which data were used to synthesise utility decrements, estimated as overweight = 0.020 (95% confidence interval 0.010-0.030), all obesity = 0.055 (0.034-0.076), obesity class 1 = 0.047 (0.017-0.077), class 2 = 0.072 (0.028-0.116) and class 3 = 0.084 (0.039-0.130). There was considerable heterogeneity in our results, which could be accounted for by the different ages and utility instruments used in the contributing studies.

CONCLUSIONS

Our results demonstrate that elevated weight status is associated with small but statistically significant reductions in utility compared with healthy weight, which will result in reduced quality-adjusted life years when extrapolated across time and used in economic evaluations.

Effectiveness of lifestyle interventions in preventing harmful weight gain among adolescents: A systematic review of systematic reviews

Obesity in adolescence is associated with stigma during school years, early emergence of co-morbidities in adulthood and premature mortality. Adolescence presents a key window of opportunity to intervene for building healthy eating and physical activity routines and prevent weight gain. This review of reviews assesses the evidence on the effectiveness of prevention interventions conducted with adolescents. Nine reviews assessing the effects of lifestyle interventions in adolescents (defined as age 10 to 19 years old) on weight gain were identified from the 10 health databases searched. Only four reviews conducted meta-analyses, of which, three (two exercise-focused) demonstrated positive changes in primary outcomes of body mass index (BMI) and/or BMI z-score (range of decrease in BMI from 0.06 to 0.47 kg/m2) ). Most were conducted in school settings, and all but two reviews were of low quality. Few reviews reported external validity components that would enable clearer directions for policy makers to implement in real-world settings. More than 140 distinct interventions were included in the reviews, but there remains a serious gap in evidence for effective interventions in adolescents.

Cost-Effectiveness of a Novel Sleep Intervention in Infancy to Prevent Overweight in Childhood

OBJECTIVE

The purpose of this study was to determine, from a health funder perspective, whether a sleep intervention, delivered in infancy, either alone or in combination with food, activity, and breastfeeding advice was cost-effective compared with usual care.

METHODS

A cost-effectiveness analysis was conducted alongside the Prevention of Overweight in Infancy (POI) randomized controlled trial for outcomes at 5 years and cost-effectiveness was modeled to age 15 years using the Early Prevention of Obesity in Childhood microsimulation model. Intervention costs for the Sleep (n = 192), Combination (n = 196), and control (n = 209) groups were determined in 2018 Australian dollars. Incremental cost-effectiveness ratios (ICERs) were determined for BMI outcomes at 5 and 15 years, with the primary outcome being quality-adjusted life years (QALYs) modeled over 15 years.

RESULTS

The average costs of the Sleep and Combination interventions were $184 and $601 per child, respectively. The ICER for the Sleep intervention was $18,125 per QALY gained, with a 74% probability of being cost-effective at a willingness-to-pay threshold of $50,000 per QALY. The ICER for the Combination intervention was $94,667 per QALY gained with a 23% probability of being cost-effective.

CONCLUSIONS

The POI Sleep intervention, without additional advice, was a low-cost and cost-effective approach to reducing childhood obesity. Sleep modification programs offer a very promising approach to obesity prevention in children.

The potential health impact of restricting less-healthy food and beverage advertising on UK television between 05.30 and 21.00 hours: A modelling study

BACKGROUND

Restrictions on the advertising of less-healthy foods and beverages is seen as one measure to tackle childhood obesity and is under active consideration by the UK government. Whilst evidence increasingly links this advertising to excess calorie intake, understanding of the potential impact of advertising restrictions on population health is limited.

METHODS AND FINDINGS

We used a proportional multi-state life table model to estimate the health impact of prohibiting the advertising of food and beverages high in fat, sugar, and salt (HFSS) from 05.30 hours to 21.00 hours (5:30 AM to 9:00 PM) on television in the UK. We used the following data to parameterise the model: children's exposure to HFSS advertising from AC Nielsen and Broadcasters' Audience Research Board (2015); effect of less-healthy food advertising on acute caloric intake in children from a published meta-analysis; population numbers and all-cause mortality rates from the Human Mortality Database for the UK (2015); body mass index distribution from the Health Survey for England (2016); disability weights for estimating disability-adjusted life years (DALYs) from the Global Burden of Disease Study; and healthcare costs from NHS England programme budgeting data. The main outcome measures were change in the percentage of the children (aged 5-17 years) with obesity defined using the International Obesity Task Force cut-points, and change in health status (DALYs). Monte Carlo analyses was used to estimate 95% uncertainty intervals (UIs). We estimate that if all HFSS advertising between 05.30 hours and 21.00 hours was withdrawn, UK children (n = 13,729,000), would see on average 1.5 fewer HFSS adverts per day and decrease caloric intake by 9.1 kcal (95% UI 0.5-17.7 kcal), which would reduce the number of children (aged 5-17 years) with obesity by 4.6% (95% UI 1.4%-9.5%) and with overweight (including obesity) by 3.6% (95% UI 1.1%-7.4%) This is equivalent to 40,000 (95% UI 12,000-81,000) fewer UK children with obesity, and 120,000 (95% UI 34,000-240,000) fewer with overweight. For children alive in 2015 (n = 13,729,000), this would avert 240,000 (95% UI 65,000-530,000) DALYs across their lifetime (i.e., followed from 2015 through to death), and result in a health-related net monetary benefit of £7.4 billion (95% UI £2.0 billion-£16 billion) to society. Under a scenario where all HFSS advertising is displaced to after 21.00 hours, rather than withdrawn, we estimate that the benefits would be reduced by around two-thirds. This is a modelling study and subject to uncertainty; we cannot fully and accurately account for all of the factors that would affect the impact of this policy if implemented. Whilst randomised trials show that children exposed to less-healthy food advertising consume more calories, there is uncertainty about the nature of the dose-response relationship between HFSS advertising and calorie intake.

CONCLUSIONS

Our results show that HFSS television advertising restrictions between 05.30 hours and 21.00 hours in the UK could make a meaningful contribution to reducing childhood obesity. We estimate that the impact on childhood obesity of this policy may be reduced by around two-thirds if adverts are displaced to after 21.00 hours rather than being withdrawn.

Estimating Age- and Sex-Specific Utility Values from the CHU9D Associated with Child and Adolescent BMI z-Score

OBJECTIVE

Our objective was to identify age- and sex-specific utilities for children and adolescents by body mass index (BMI) z-score.

METHODS

We used data from 6822 participants and 12,094 observations from two cohorts and two waves of interviews from the Longitudinal Study of Australian Children. We fit linear models using generalised estimating equations to investigate associations between Child Health Utility 9D and BMI z-score in girls and boys aged 10-17 years. We initially fit models for each sex, fully adjusted for known predictors of health-related quality of life, including socioeconomic position, long-term medical condition and maternal smoking status and also included an interaction between age and BMI z-score to examine age-specific effects. Finally, we derived a minimal model for each sex by eliminating interaction terms with P > 0.01 and predictors with P > 0.05.

RESULTS

Our adjusted results show different utility patterns in girls and boys. In girls, utility decrements for each unit increase in BMI z-score changed with age (P < 0.01 for interaction between age and BMI z-score). At age 10 years, the mean utility decrement for each unit increase in BMI z-score was 0.002 (95% confidence interval [CI] 0.011 decrement to 0.006 increment), but, by age 17 years, this utility decrement was 0.023 (95% CI 0.013 to 0.032). In boys, small non-significant decrements were found in utility for each unit increase in BMI z-score, with no observable change with age.

CONCLUSION

Our analyses demonstrated that age and sex should be considered when attributing utility values and decrements to BMI z-scores.

Mind the (inter-rater) gap. An investigation of self-reported versus proxy-reported assessments in the derivation of childhood utility values for economic evaluation: A systematic review

PURPOSE

Evidence surrounding utilities for health states, derived either directly from the application of preference-based valuation methods or indirectly from the application of preference-based quality of life instruments, is increasingly being utilised to inform the cost-effectiveness of child health interventions. Proxy (parent or health professional) assessments are common in this area. This study sought to investigate the degree of convergence in childhood utilities generated directly or indirectly within dyad child and proxy assessments.

METHODS

A systematic literature review was conducted following PRISMA guidelines. A comprehensive literature search strategy conducted across six search engines (PubMed, Embase, Web of Science, PsychoINFO, EconLit, CINAHL and Cochrane Library). Original peer-reviewed articles that reported utilities derived directly or indirectly using simultaneous dyad child and proxy assessments were extracted. Mean and median utilities, correlation coefficients and levels of agreement were extracted, catalogued and assessed.

RESULTS

A total of 35 studies that reported utilities for two or more respondent types were identified. Of these, 29 studies reported dyad childhood self-report and proxy utilities whilst six studies reported levels of agreement and/or correlations only without documenting overall utilities. Proxy assessment was most often conducted by parents with the HUI3 representing the most commonly applied instrument across a range of health conditions. The utilities derived from child and parent proxy assessment were bidirectional with parental proxies tending to underestimate and health professional proxies tending to overestimate relative to child self-reports. Inter-rater agreement between child self-reports and parent-proxy reports were poorer for more subjective attributes (cognition, emotion and pain), relative to physical attributes (mobility, self-care, speech, vision) of health-related quality of life.

CONCLUSIONS

Childhood utilities derived from children or proxies are not interchangeable. The choice of self or proxy assessor may have potentially significant implications for economic evaluations of child health interventions.

The potential for long-term cost-effectiveness of obesity prevention interventions in the early years of life

BACKGROUND

Early childhood obesity prevention is gaining increasing importance, as the prevalence of children with overweight and obesity aged 5 years and under increases worldwide. Along with understanding the effectiveness of obesity interventions, it is important to understand the cost-effectiveness of interventions over time.

OBJECTIVES

To estimate the long-term health benefits and health care cost-savings of reductions in BMI for the Australian population of children aged between 2 and 5 years.

METHODS

A proportional multistate, multiple cohort lifetable model estimated the health benefits and health care cost-savings related to hypothetical reductions in BMI, informed by a scoping review of systematic reviews reporting the effectiveness of obesity prevention interventions in preschool aged children.

RESULTS

Results suggest significant potential for cost-effectiveness of obesity prevention interventions in preschool-aged children if intervention effect can be maintained. A relatively small population level reduction in BMI z-score (-0.13 BMIz) in children aged 2 to 5 years would result in 36 496 health-adjusted life years saved (95% uncertainty interval [UI], 30 283-42 945) and health care cost-savings of approximately $301 million (95% UI $234 million-$369 million) if modelled over the lifetime.

CONCLUSIONS

Scenario results highlight the importance of obesity intervention in the early years of life.

Patterns, trends and methodological associations in the measurement and valuation of childhood health utilities

PURPOSE

To systematically assess patterns and temporal changes in the measurement and valuation of childhood health utilities and associations between methodological factors.

METHODS

Studies reporting childhood health utilities using direct or indirect valuation methods, published by June 2017, were identified through PubMed, Embase, Web of Science, PsycINFO, EconLit, CINAHL, Cochrane Library and PEDE. The following were explored: patterns in tariff application; linear trends in numbers of studies/samples and paediatric cost-utility analyses (CUAs) and associations between them; changes in proportions of studies/samples within characteristic-based categories over pre-specified periods; impact of National Institute for Health and Care Excellence (NICE) guidance on primary UK research and associations between valuation method, age and methodological factors.

RESULTS

335 studies with 3974 samples covering all ICD-10 chapters, 23 valuation methods, 12 respondent types and 42 countries were identified by systematic review. 34.0% of samples using indirect methods compatible with childhood applied childhood-derived tariffs. There was no association between numbers of studies/samples and numbers of CUAs. Compared to 1990-2008, 2009-June 2017 saw a significant fall in the proportion of studies using case series; significant compositional changes across ICD-10 chapters and significantly higher sample proportions using childhood-specific and adult-specific indirect valuation methods, and based on pre-adolescents, self-assessment, self-administration and experienced health states. NICE guidance was weakly effective in promoting reference methods. Associations between valuation method, age and methodological factors were significant.

CONCLUSION

1990-2017 witnessed significant changes in primary research on childhood health utilities. Health technology assessment agencies should note the equivocal effect of methodological guidance on primary research.

A New Model for Evaluation of Interventions to Prevent Obesity in Early Childhood

Background: Childhood obesity is a serious public health issue. In Australia, 1 in 4 children is already affected by overweight or obesity at the time of school entry. Governments around the world have recognized this problem through investment in the prevention of pediatric obesity, yet few interventions in early childhood have been subjected to economic evaluation. Information on cost-effectiveness is vital to decisions about program implementation. A challenge in evaluating preventive interventions in early childhood is to capture long-term costs and outcomes beyond the duration of an intervention, as the benefits of early obesity prevention will not be realized until some years into the future. However, decisions need to be made in the present, and modeling is one way to inform such decisions. Objective: To describe the conceptual structure of a new health economic model (the Early Prevention of Obesity in CHildhood (EPOCH) model) for evaluating childhood obesity interventions; and to validate the epidemiologic predictions. Methods and Results: We use an individual-level (micro-simulation) method to model BMI trajectories and the progression of obesity from early childhood to adolescence. The equations predicting individual BMI change underpinning our model were derived from data from the population-representative study, the Longitudinal Study of Australian Children (LSAC). Our approach is novel because it will account for costs and benefits accrued throughout childhood and adolescence. As a first step to validate the epidemiological predictions of the model, we used input data representing over 250,000 children aged 4/5 years, and simulated BMI and obesity trajectories until adolescence. Simulated mean BMI and obesity prevalence for boys and girls were verified by nationally-representative data on children at 14/15 years of age. Discussion: The EPOCH model is epidemiologically sound in its prediction of both BMI trajectories and prevalence of obesity for boys and girls. Future developments of the model will include socio-economic position and will incorporate the impacts of obesity on healthcare costs. The EPOCH model will help answer: when is it best to intervene in childhood; what are the most cost-effective approaches and which population groups will benefit most from interventions.

Relationship Between Fat Mass and Obesity-Associated (FTO) Gene Polymorphisms with Obesity and Metabolic Syndrome in Ethnic Mongolians

Background

The distribution of fat mass and obesity-associated gene (FTO) genes rs9939609 and rs1421085 in obese and normal ethnic Mongolians was analyzed to investigate the association of FTO gene polymorphisms with obesity and metabolic syndrome in ethnic Mongolians.

Material/Methods

The genotypes of FTO genes rs9939609 and rs1421085 in 500 subjects were detected by allele-specific PCR (AS-PCR). General characteristics and clinical biochemical indicators were compared between the obesity group and the control group. The correlation between different genotypes and obesity metabolic index was also analyzed.

Results

Body mass, body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-hip ratio (WHR), SBP, DBP, FPG, triglyceride (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) were higher, while HDL-C was lower in the obesity group compared with controls. The frequencies of TT genotype and T allele in the obesity group were higher than those in the control group. The frequencies of these 3 genotypes and allele frequencies of Rs1421085 were comparable between the 2 groups (P>0.05). The risk of obesity in Mongolian individuals carrying rs9939609 AT genotype was 1.312 times higher and the risk in those carrying AA genotype was 1.896 times higher than in individuals with TT genotype. The body weight, BMI, WC, HC, and WHR in individuals with rs9939609 AA and AT genotypes were significantly higher than in those with TT genotype.

Conclusions

The AT/AA genotype and allele A of rs9939609 are associated with an increased risk of obesity.

Is there an association between early weight status and utility-based health-related quality of life in young children?

PURPOSE

Few studies focus on the health-related quality of life (HRQoL) of preschool children with overweight or obesity. This is relevant for evaluation of obesity prevention trials using a quality-adjusted life year (QALY) framework. This study examined the association between weight status in the preschool years and HRQoL at age 5 years, using a preference-based instrument.

METHODS

HRQoL [based on parent proxy version of the Health Utilities Index Mark 3 (HUI3)] and weight status were measured in children born in Australia between 2007 and 2009. Children's health status was scored across eight attributes of the HUI3-vision, hearing, speech, ambulation, dexterity, emotion, cognition and pain, and these were used to calculate a multi-attribute utility score. Ordinary least squares (OLS), Tobit and two-part regressions were used to model the association between weight status and multi-attribute utility.

RESULTS

Of the 368 children for whom weight status and HUI3 data were available, around 40% had overweight/obesity. After adjusting for child's sex, maternal education, marital status and household income, no significant association between weight status in the preschool years and multi-attribute utility scores at 5 years was found.

CONCLUSIONS

Alternative approaches for capturing the effects of weight status in the preschool years on preference-based HRQoL outcomes should be tested. The application of the QALY framework to economic evaluations of obesity-related interventions in young children should also consider longitudinal effects over the life-course. Clinical Trial Registration The Healthy Beginnings Trial was registered with the Australian Clinical Trial Registry (ACTRNO12607000168459).