Modeling health gains and cost savings for ten dietary salt reduction targets

Estimated effects of reductions in processed meat consumption and unprocessed red meat consumption on occurrences of type 2 diabetes, cardiovascular disease, colorectal cancer, and mortality in the USA: a microsimulation study

BACKGROUND

High consumption of processed meat and unprocessed red meat is associated with increased risk of multiple chronic diseases, although there is substantial uncertainty regarding the relationship for unprocessed red meat. We developed a microsimulation model to estimate how reductions in processed meat and unprocessed red meat consumption could affect rates of type 2 diabetes, cardiovascular disease, colorectal cancer, and mortality in the US adult population.

METHODS

We used data from two versions of the US National Health and Nutrition Examination Survey, one conducted during 2015-16 and one conducted during 2017-18, to create a simulated US population. The starting cohort was restricted to respondents aged 18 years or older who were not pregnant and had 2 days of dietary-recall data. First, we used previously developed risk models to estimate the baseline disease risk of an individual. For type 2 diabetes we used a logistic-regression model and for cardiovascular disease and colorectal cancer we used Cox proportional-hazard models. We then multiplied baseline risk by relative risk associated with individual processed meat and unprocessed red meat consumption. Prevented occurrences of type 2 diabetes, cardiovascular disease, colorectal cancer, and mortality were computed by taking the difference between the incidence in the baseline and intervention scenarios. All stages were repeated for ten iterations to correspond to a 10-year time span. Scenarios were reductions of 5%, 10%, 30%, 50%, 75%, and 100% in grams consumed of processed meat, unprocessed red meat, or both. Each scenario was repeated 50 times for uncertainty analysis.

FINDINGS

The total number of individual respondents included in the simulated population was 8665, representing 242 021 876 US adults. 4493 (51·9%) of 8665 individuals were female and 4172 (48·1%) were male; mean age was 49·54 years (SD 18·38). At baseline, weighted mean daily consumption of processed meat was 29·1 g, with a 30% reduction being 8·7 g per day, and of unprocessed red meat was 46·7 g, with a 30% reduction being 14·0 g per day. We estimated that a 30% reduction in processed meat intake alone could lead to 352 900 (95% uncertainty interval 345 500-359 900) fewer occurrences of type 2 diabetes, 92 500 (85 600-99 900) fewer occurrences of cardiovascular disease, 53 300 (51 400-55 000) fewer occurrences of colorectal cancer, and 16 700 (15 300-17 700) fewer all-cause deaths during the 10-year period. A 30% reduction in unprocessed red meat intake alone could lead to 732 600 (725 700-740 400) fewer occurrences of type 2 diabetes, 291 500 (283 900-298 800) fewer occurrences of cardiovascular disease, 32 200 (31 500-32 700) fewer occurrences of colorectal cancer, and 46 100 (45 300-47 200) fewer all-cause deaths during the 10-year period. A 30% reduction in both processed meat and unprocessed red meat intake could lead to 1 073 400 (1 060 100-1 084 700) fewer occurrences of type 2 diabetes, 382 400 (372 100-391 000) fewer occurrences of cardiovascular disease, 84 400 (82 100-86 200) fewer occurrences of colorectal cancer, and 62 200 (60 600-64 400) fewer all-cause deaths during the 10-year period.

INTERPRETATION

Reductions in processed meat consumption could reduce the burden of some chronic diseases in the USA. However, more research is needed to increase certainty in the estimated effects of reducing unprocessed red meat consumption.

FUNDING

The Wellcome Trust.

Estimated Dietary and Health Impact of the World Health Organization's Global Sodium Benchmarks on Packaged Foods in Australia: a Modeling Study

BACKGROUND

In 2021, the World Health Organization (WHO) set sodium benchmarks for packaged foods to guide countries in setting feasible and effective sodium reformulation programs. We modeled the dietary and health impact of full compliance with the WHO's sodium benchmarks in Australia and compared it to the potential impact of Australia's 2020 sodium reformulation targets.

METHODS

We used nationally representative data on food and sodium intake, sodium levels in packaged foods, and food sales volume to estimate sodium intake pre- and post-implementation of the WHO and Australia's sodium benchmarks for 24 age-sex groups. Using comparative risk assessment models, we then estimated the potential deaths, incidence, and disability-adjusted life years averted from cardiovascular disease, chronic kidney disease, and stomach cancer based on the reductions in sodium intake.

RESULTS

Compliance with the WHO's sodium benchmarks for packaged foods in Australia could lower mean adult sodium intake by 404 mg/day, corresponding to a 12% reduction. This could prevent about 1770 deaths/year (95% uncertainty interval 1168-2587), corresponding to 3% of all cardiovascular disease, chronic kidney disease, and stomach cancer deaths in Australia, and prevent some 6900 (4603-9513) new cases, and 25 700 (17 655-35 796) disability-adjusted life years/year. Compared with Australian targets, the WHO benchmarks will avert around 3 and a half times more deaths each year (1770 versus 510).

CONCLUSIONS

Substantially greater health impact could be achieved if the Australian government strengthened its current sodium reformulation program by adopting WHO's more stringent and comprehensive sodium benchmarks.

Prioritization of intervention domains to prevent cardiovascular disease: a country-level case study using global burden of disease and local data

AIM

We aimed to combine Global Burden of Disease (GBD) Study data and local data to identify the highest priority intervention domains for preventing cardiovascular disease (CVD) in the case study country of Aotearoa New Zealand (NZ).

METHODS

Risk factor data for CVD in NZ were extracted from the GBD using the "GBD Results Tool." We prioritized risk factor domains based on consideration of the size of the health burden (disability-adjusted life years [DALYs]) and then by the domain-specific interventions that delivered the highest health gains and cost-savings.

RESULTS

Based on the size of the CVD health burden in DALYs, the five top prioritized risk factor domains were: high systolic blood pressure (84,800 DALYs; 5400 deaths in 2019), then dietary risk factors, then high LDL cholesterol, then high BMI and then tobacco (30,400 DALYs; 1400 deaths). But if policy-makers aimed to maximize health gain and cost-savings from specific interventions that have been studied, then they would favor the dietary risk domain (e.g., a combined fruit and vegetable subsidy plus a sugar tax produced estimated lifetime savings of 894,000 health-adjusted life years and health system cost-savings of US$11.0 billion; both 3% discount rate). Other potential considerations for prioritization included the potential for total health gain that includes non-CVD health loss and potential for achieving relatively greater per capita health gain for Māori (Indigenous) to reduce health inequities.

CONCLUSIONS

We were able to show how CVD risk factor domains could be systematically prioritized using a mix of GBD and country-level data. Addressing high systolic blood pressure would be the top ranked domain if policy-makers focused just on the size of the health loss. But if policy-makers wished to maximize health gain and cost-savings using evaluated interventions, dietary interventions would be prioritized, e.g., food taxes and subsidies.

Estimating Canadian sodium intakes and the health impact of meeting national and WHO recommended sodium intake levels: A macrosimulation modelling study

BACKGROUND

Cardiovascular diseases (CVDs) are the second leading cause of total deaths in Canada. High blood pressure is the main metabolic risk factor for developing CVDs. It has been well established that excess consumption of sodium adversely affects blood pressure. Canadians' mean sodium intakes are well above recommended levels. Reducing dietary sodium intake through food reformulation has been identified as a cost-effective intervention, however, dietary sodium intake and the potential health impact of meeting recommended sodium intake levels due to food reformulation have not been determined in Canada.

OBJECTIVE

This study aimed to 1) obtain robust estimates of Canadians' usual sodium intakes, 2) model sodium intakes had foods been reformulated to align with Health Canada's sodium reduction targets, and 3) estimate the number of CVD deaths that could be averted or delayed if Canadian adults were to reduce their mean sodium intake to recommended levels under three scenarios: A) 2,300 mg/d-driven by a reduction of sodium levels in packaged foods to meet Health Canada targets (reformulation); B) 2,000 mg/d to meet the World Health Organization (WHO) recommendation; and C) 1,500 mg/d to meet the Adequate Intake recommendation.

METHODS

Foods in the University of Toronto's Food Label Information Program 2017, a Canadian branded food composition database, were linked to nationally representative food intake data from the 2015 Canadian Community Health Survey-Nutrition to estimate sodium intakes (and intakes had Health Canada's reformulation strategy been fully implemented). The Preventable Risk Integrated ModEl (PRIME) was used to estimate potential health impact.

RESULTS

Overall, mean sodium intake was 2758 mg/day, varying by age and sex group. Based on 'reformulation' scenario A, mean sodium intakes were reduced by 459 mg/day, to 2299 mg/day. Reducing Canadians' sodium intake to recommended levels under scenarios A, B and C could have averted or delayed 2,176 (95% UI 869-3,687), 3,252 (95% UI 1,380-5,321), and 5,296 (95% UI 2,190-8,311) deaths due to CVDs, respectively, mainly from ischaemic heart disease, stroke, and hypertensive disease. This represents 3.7%, 5.6%, and 9.1%, respectively, of the total number of CVDs deaths observed in Canada in 2019.

CONCLUSION

Results suggest that reducing sodium intake to recommended levels could prevent or postpone a substantial number of CVD deaths in Canada. Reduced sodium intakes could be achieved through reformulation of the Canadian food supply. However, it will require higher compliance from the food industry to achieve Health Canada's voluntary benchmark sodium reduction targets.

Dietary sources of sodium across the diverse New Zealand adult population

•

Fourteen major food groups provide 80% of sodium consumed by NZ adults.

•

‘Bread’ and ‘Bread-based dishes’ were major sources of sodium for all population groups.

•

‘Soups and stocks’, ‘Poultry’, ‘Pork’, and ‘Vegetables’ were major sources of sodium specific to population sub-groups.

•

Taking a total population approach to sodium reduction in New Zealand risks increasing inequities in heart health.

Our aim was to determine dietary sources of sodium for adults in Aotearoa New Zealand (NZ). We used data from the most recent NZ Adult Nutrition Survey (ANS 2008/09) including 4,721 free-living adults aged 15+ years who completed a single 24-hour dietary recall. Population weighted percentage contribution to dietary sodium was calculated and ranked for major and minor food categories across the total population and by gender (male and female), ethnicity (Māori, Pacific, Asian, and Other), and age (15 to 20, 21 to 40, 41 to 60, and 61+ years). Fifteen major food categories contributed ∼80% of sodium consumed by the total population; the top five were ‘Bread’ (18%), ‘Bread-based dishes’ (11%), ‘Grains and pasta’ (7%), ‘Pork’ (7%), and ‘Sausages and processed meats’ (5%). Compared to other sub-groups within the same demographic, the top-five major sources of sodium specific to Females were ‘Soups and stocks’, Pacific communities were Poultry, Māori whānau was ‘Pork’, Others was ‘Pork’, Asian was ‘Soups and stocks’ and ‘Vegetables’, and 61+ years was ‘Soups and stocks’. Our findings provide information on the major and minor food sources of sodium for the diverse NZ population. The differences observed in major dietary sources by population subgroup are critical for policymakers to include in the development of any future country-specific sodium reduction targets; repeating the total population approach taken in several other countries is unlikely to improve inquities in heart-related health in NZ.

Sodium and Health: Old Myths and a Controversy Based on Denial

PURPOSE OF REVIEW

The scientific consensus on which global health organizations base public health policies is that high sodium intake increases blood pressure (BP) in a linear fashion contributing to cardiovascular disease (CVD). A moderate reduction in sodium intake to 2000 mg per day helps ensure that BP remains at a healthy level to reduce the burden of CVD.

RECENT FINDINGS

Yet, since as long ago as 1988, and more recently in eight articles published in the European Heart Journal in 2020 and 2021, some researchers have propagated a myth that reducing sodium does not consistently reduce CVD but rather that lower sodium might increase the risk of CVD. These claims are not well-founded and support some food and beverage industry's vested interests in the use of excessive amounts of salt to preserve food, enhance taste, and increase thirst. Nevertheless, some researchers, often with funding from the food industry, continue to publish such claims without addressing the numerous objections. This article analyzes the eight articles as a case study, summarizes misleading claims, their objections, and it offers possible reasons for such claims. Our study calls upon journal editors to ensure that unfounded claims about sodium intake be rigorously challenged by independent reviewers before publication; to avoid editorial writers who have been co-authors with the subject paper's authors; to require statements of conflict of interest; and to ensure that their pages are used only by those who seek to advance knowledge by engaging in the scientific method and its collegial pursuit. The public interest in the prevention and treatment of disease requires no less.

Estimating the cost-effectiveness of the Sodium Reduction in Communities Program

OBJECTIVE

This study assessed the cost-effectiveness of the Centers for Disease Control and Prevention's (CDC's) Sodium Reduction in Communities Program (SRCP).

DESIGN

We collected implementation costs and performance measure indicators from SRCP recipients and their partner food service organisations. We estimated the cost per person and per food service organisation reached and the cost per menu item impacted. We estimated the short-term effectiveness of SRCP in reducing sodium consumption and used it as an input in the Prevention Impact Simulation Model to project the long-term impact on medical cost savings and quality-adjusted life-years gained due to a reduction in CVD and estimate the cost-effectiveness of SRCP if sustained through 2025 and 2040.

SETTING

CDC funded eight recipients as part of the 2016-2021 round of the SRCP to work with food service organisations in eight settings to increase the availability and purchase of lower-sodium food options.

PARTICIPANTS

Eight SRCP recipients and twenty of their partners.

RESULTS

At the recipient level, average cost per person reached was $10, and average cost per food service organisation reached was $42 917. At the food service organisation level, median monthly cost per food item impacted by recipe modification or product substitution was $684. Cost-effectiveness analyses showed that, if sustained, the programme is cost saving (i.e. the reduction in medical costs is greater than the implementation costs) in the target population by $1·82 through 2025 and $2·09 through 2040.

CONCLUSIONS

By providing evidence of the cost-effectiveness of a real-world sodium reduction initiative, this study can help inform decisions by public health organisations about related CVD prevention interventions.

Strategic Sodium Reduction Initiative Reduces Sodium in Meals Served at Older Adult Congregate Meal Program Sites

Excessive sodium consumption is a public health issue and congregate meal programs provide a unique opportunity to reduce sodium served to a large, at-risk population. A Sodium Reduction Initiative (SRI) was implemented in a congregate meal program that serves over 3,000 older adults. Nutrient analyses conducted at baseline and post-intervention were used to calculate average sodium reduction and the number of low sodium foods; targeted foods were categorized by strategy. Customer satisfaction surveys were collected at baseline and 3- and 6-months post-intervention. Kruskal Wallis and analysis of variance were used to compare sodium reduction differences. Chi-square analysis determined associations among strategies. The SRI impacted 55 foods, low sodium foods increased by 22%, and the average sodium per menu cycle was reduced by 21%. Replacement with a lower sodium food was the most frequently used strategy and had the largest sodium reduction. Sauces and main entrees were most frequently impacted, and thirteen ingredients accounted for 75% of all reduced-sodium foods. Over 50% of the 1,424 survey respondents consumed the reduced-sodium foods and food satisfaction remained stable from baseline to post-intervention. Congregate meals programs that target commonly used foods and key ingredients can significantly reduce sodium served to older adults.

The estimated health impact of sodium reduction through food reformulation in Australia: A modeling study

BACKGROUND

The Australian Government recently established sodium targets for packaged foods to encourage voluntary reformulation to reduce population sodium consumption and related diseases. We modeled the health impact of Australia's sodium reformulation targets and additional likely health gains if more ambitious, yet feasible sodium targets had been adopted instead.

METHODS AND FINDINGS

Using comparative risk assessment models, we estimated the averted deaths, incidence, and disability-adjusted life years (DALYs) from cardiovascular disease (CVD), chronic kidney disease (CKD) and stomach cancer after implementation of (a) Australia's sodium targets (overall and by individual companies); (b) United Kingdom's targets (that covers more product categories); and (c) an optimistic scenario (sales-weighted 25th percentile sodium content for each food category included in the UK program). We used nationally representative data to estimate pre- and post-intervention sodium intake, and other key data sources from the Global Burden of Disease study. Full compliance with the Australian government's sodium targets could prevent approximately 510 deaths/year (95% UI, 335 to 757), corresponding to about 1% of CVD, CKD, and stomach cancer deaths, and prevent some 1,920 (1,274 to 2,600) new cases and 7,240 (5,138 to 10,008) DALYs/year attributable to these diseases. Over half (59%) of deaths prevented is attributed to reformulation by 5 market-dominant companies. Compliance with the UK and optimistic scenario could avert approximately an additional 660 (207 to 1,227) and 1,070 (511 to 1,856) deaths/year, respectively, compared to Australia's targets. The main limitation of this study (like other modeling studies) is that it does not prove that sodium reformulation programs will prevent deaths and disease events; rather, it provides the best quantitative estimates and the corresponding uncertainty of the potential effect of the different programs to guide the design of policies.

CONCLUSIONS

There is significant potential to strengthen Australia's sodium reformulation targets to improve its health impact. Promoting compliance by market-dominant food companies will be critical to achieving the potential health gains.

Simulation Modeling for the Economic Evaluation of Population-Based Dietary Policies: A Systematic Scoping Review

Simulation modeling can be useful to estimate the long-term health and economic impacts of population-based dietary policies. We conducted a systematic scoping review following the PRISMA-ScR (Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews) guideline to map and critically appraise economic evaluations of population-based dietary policies using simulation models. We searched Medline, Embase, and EconLit for studies published in English after 2005. Modeling studies were mapped based on model type, dietary policy, and nutritional target, and modeled risk factor-outcome pathways were analyzed. We included 56 studies comprising 136 model applications evaluating dietary policies in 21 countries. The policies most often assessed were reformulation (34/136), taxation (27/136), and labeling (20/136); the most common targets were salt/sodium (60/136), sugar-sweetened beverages (31/136), and fruit and vegetables (15/136). Model types included Markov-type (35/56), microsimulation (11/56), and comparative risk assessment (7/56) models. Overall, the key diet-related risk factors and health outcomes were modeled, but only 1 study included overall diet quality as a risk factor. Information about validation was only reported in 19 of 56 studies and few studies (14/56) analyzed the equity impacts of policies. Commonly included cost components were health sector (52/56) and public sector implementation costs (35/56), as opposed to private sector (18/56), lost productivity (11/56), and informal care costs (3/56). Most dietary policies (103/136) were evaluated as cost-saving independent of the applied costing perspective. An analysis of the main limitations reported by authors revealed that model validity, uncertainty of dietary effect estimates, and long-term intervention assumptions necessitate a careful interpretation of results. In conclusion, simulation modeling is widely applied in the economic evaluation of population-based dietary policies but rarely takes dietary complexity and the equity dimensions of policies into account. To increase relevance for policymakers and support diet-related disease prevention, economic effects beyond the health sector should be considered, and transparent conduct and reporting of model validation should be improved.

Impact of the 2003 to 2018 Population Salt Intake Reduction Program in England: A Modeling Study

Supplemental Digital Content is available in the text.

The United Kingdom was among the first countries to introduce a salt reduction program in 2003 to reduce cardiovascular disease (CVD) incidence risk. Despite its initial success, the program has stalled recently and is yet to achieve national and international targets. We used age- and sex-stratified salt intake of 19 to 64 years old participants in the National Diet and Nutrition Surveys 2000 to 2018 and a multistate life table model to assess the effects of the voluntary dietary salt reduction program on premature CVD, quality-adjusted survival, and health care and social care costs in England. The program reduced population-level salt intake from 9.38 grams/day per adult (SE, 0.16) in 2000 to 8.38 grams/day per adult (SE, 0.17) in 2018. Compared with a scenario of persistent 2000 levels, assuming that the population-level salt intake is maintained at 2018 values, by 2050, the program is projected to avoid 83 140 (95% CI, 73 710–84 520) premature ischemic heart disease (IHD) cases and 110 730 (95% CI, 98 390–112 260) premature strokes, generating 542 850 (95% CI, 529 020–556 850) extra quality-adjusted life-years and £1640 million (95% CI, £1570–£1660) health care cost savings for the adult population of England. We also projected the gains of achieving the World Health Organization target of 5 grams/day per adult by 2030, which by 2050 would avert further 87 870 (95% CI, 82 050–88 470) premature IHD cases, 126 010 (95% CI, 118 600–126 460) premature strokes and achieve £1260 million (95% CI, £1180–£1260) extra health care savings compared with maintaining 2018 levels. Strengthening the salt reduction program to achieve further reductions in population salt intake and CVD burden should be a high priority.

Monitoring and implementation of salt reduction initiatives in Africa: A systematic review

This systematic review aims to document salt consumption patterns and the implementation status and potential impact of salt reduction initiatives in Africa, from studies published between January 2009 and November 2019. Studies were sourced using MEDLINE, Embase, Cochrane Library electronic databases, and gray literature. Of the 887 records retrieved, 38 studies conducted in 18 African countries were included. Twelve studies measured population salt intake, 11 examined salt level in foods, 11 assessed consumer knowledge, attitudes, and behaviors, 1 study evaluated a behavior change intervention, and 3 studies modeled potential health gains and cost savings of salt reduction interventions. The population salt intake studies determined by 24‐hour urine collections showed that the mean (SD) salt intake in African adults ranged from 6.8 (2.2) g to 11.3 (5.4) g/d. Salt levels in foods were generally high, and consumer knowledge was fairly high but did not seem to translate into salt lowering behaviors. Modeling studies showed that interventions for reducing dietary sodium would generate large health gains and cost savings for the health system. Despite this evidence, adoption of population salt reduction strategies in Africa has been slow, and dietary consumption of sodium remains high. Only South Africa adopted legislation in 2016 to reduce population salt intake, but success of this intervention has not yet been fully evaluated. Thus, rigorous evaluation of the salt reduction legislation in South Africa and initiation of salt reduction programs in other African countries will be vital to achieving the targeted 30% reduction in salt intake by 2025.

Reducing children's sugar intake through food reformulation: methods for estimating sugar reduction program targets, using New Zealand as a case study

BACKGROUND

Reducing sugar in packaged foods and beverages could help protect children's future health. Clear methods for the development of feasible yet impactful sugar reduction program targets are needed.

OBJECTIVES

To outline methods for the development of program targets that would reduce, by 20%, the total sugar content of packaged foods and beverages commonly consumed by children. New Zealand (NZ) is used as a case study.

METHODS

Sugar content and pack size targets were developed using a 6-step process informed by the UK sugar and salt reduction programs. Food groups contributing ≥2% to children's total sugar intake were identified using national dietary survey data. Consumption volume, sugar content, and pack size were obtained from household panel data linked with a packaged food composition database. Category-specific targets were set as 20% reductions in sales-weighted means adjusted for feasibility, i.e., ∼1/3 of products already meeting the target, and alignment with existing, relevant targets.

RESULTS

Twenty-two food groups were identified as major contributors to NZ children's total sugar intake. Mean reductions required in sugar content and pack size to meet the targets were 5.2 g  per 100 g/mL (26%) and 61.2 g/mL/pack (23%), respectively. The percentage of products already meeting the sugar targets ranged from 14% for electrolyte drinks and flavored dairy milk to 50% for cereal bars, and for pack size targets compliance ranged from 32% for chocolate confectionary to 62% for fruit juices and drinks. Estimated reductions in annual household sugar purchases if the sugar and pack size targets were met were 1459 g (23%) and 286 g (6%), respectively.

CONCLUSIONS

Methods for the development of sugar and pack size reduction targets are presented, providing a robust, step-by-step process for countries to follow. The results of the case study provide a suggested benchmark for a potential national sugar reduction program in NZ.

Preventive Pharmacotherapy for Cardiovascular Disease: A Modelling Study Considering Health Gain, Costs, and Cost-Effectiveness when Stratifying by Absolute Risk

Cardiovascular disease (CVD) is the leading cause of death internationally. We aimed to model the impact of CVD preventive double therapy (a statin and anti-hypertensive) by clinician-assessed absolute risk level. An established and validated multi-state life-table model for the national New Zealand (NZ) population was adapted. The new version of the model specifically considered the 60–64-year-old male population which was stratified by risk using a published NZ-specific CVD risk equation. The intervention period of treatment was for five years, but a lifetime horizon was used for measuring benefits and costs (a five-year horizon was also implemented). We found that for this group offering double therapy was highly cost-effective in all absolute risk categories (eg, NZ$1580 per QALY gained in the >20% in 5 years risk stratum; 95%UI: Dominant to NZ$3990). Even in the lowest risk stratum (≤5% risk in 5 years), the cost per QALY was only NZ$25,500 (NZ$28,200 and US$19,100 in 2018). At an individual level, the gain for those who responded to the screening offer and commenced preventive treatment ranged from 0.6 to 4.9 months of quality-adjusted life gained (or less than a month gain with a five-year horizon). Nevertheless, at the individual level, patient considerations are critical as some people may decide that this amount of average health gain does not justify taking daily medication.

Estimating the cost-effectiveness of salt reformulation and increasing access to leisure centres in England, with PRIMEtime CE model validation using the AdViSHE tool

BACKGROUND

PRIMEtime CE is a multistate life table model that can directly compare the cost effectiveness of public health interventions affecting diet and physical activity levels, helping to inform decisions about how to spend finite resources. This paper estimates the costs and health outcomes in England of two scenarios: reformulating salt and expanding subsidised access to leisure centres. The results are used to help validate PRIMEtime CE, following the steps outlined in the Assessment of the Validation Status of Health-Economic decision models (AdViSHE) tool.

METHODS

The PRIMEtime CE model estimates the difference in quality adjusted life years (QALYs) and difference in NHS and social care costs of modelled interventions compared with doing nothing. The salt reformulation scenario models how salt consumption would change if food producers met the 2017 UK Food Standards Agency salt reformulation targets. The leisure centre scenario models change in physical activity levels if the Birmingham Be Active scheme (where swimming pools and gym access is free to residents during defined periods) was rolled out across England. The AdViSHE tool was developed by health economic modellers and divides model validation into five parts: validation of the conceptual model, input data validation, validation of computerised model, operational validation, and other validation techniques. PRIMEtime CE is discussed in relation to each part.

RESULTS

Salt reformulation was dominant compared with doing nothing, and had a 10-year return on investment of £1.44 (£0.50 to £2.94) for every £1 spent. By contrast, over 10 years the Be Active expansion would cost £727,000 (£514,000 to £1,064,000) per QALY. PRIMEtime CE has good face validity of its conceptual model and has robust input data. Cross-validation produces mixed results and shows the impact of model scope, input parameters, and model structure on cost-per-QALY estimates.

CONCLUSIONS

This paper illustrates how PRIMEtime CE can be used to compare the cost-effectiveness of two different public health measures affecting diet and physical activity levels. The AdViSHE tool helps to validate PRIMEtime CE, identifies some of the key drivers of model estimates, and highlights the challenges of externally validating public health economic models against independent data.

PRIMEtime CE: a multistate life table model for estimating the cost-effectiveness of interventions affecting diet and physical activity

BACKGROUND

Non-communicable diseases are the leading cause of death in England, and poor diet and physical inactivity are two of the principle behavioural risk factors. In the context of increasingly constrained financial resources, decision makers in England need to be able to compare the potential costs and health outcomes of different public health policies aimed at improving these risk factors in order to know where to invest so that they can maximise population health. This paper describes PRIMEtime CE, a multistate life table cost-effectiveness model that can directly compare interventions affecting multiple disease outcomes.

METHODS

The multistate life table model, PRIMEtime Cost Effectiveness (PRIMEtime CE), is developed from the Preventable Risk Integrated ModEl (PRIME) and the PRIMEtime model. PRIMEtime CE uses routinely available data to estimate how changing diet and physical activity in England affects morbidity and mortality from heart disease, stroke, diabetes, liver disease, and cancers either directly or via raised blood pressure, cholesterol, and body weight.

RESULTS

Model outcomes are change in quality adjusted life years, and change in English National Health Service and social care costs.

CONCLUSION

This paper describes PRIMEtime CE and highlights its main strengths and limitations. The model can be used to compare any number of public policies affecting diet and physical activity, allowing decision makers to understand how they can maximise population health with limited financial resources.

Estimating the health benefits and cost-savings of a cap on the size of single serve sugar-sweetened beverages

Sugar-sweetened beverage (SSB) intake is associated with tooth decay, obesity and diabetes. We aimed to model the health and cost impact of reducing the serving size of all single serve SSB to a maximum of 250 ml in New Zealand. A 250 ml serving size cap was modeled for all instances of single serves (<600 ml) of sugar-sweetened carbonated soft drinks, fruit drinks, carbonated energy drinks, and sports drinks in the New Zealand National Nutrition Survey intake data (2008/09). A multi-state life-table model used the change in energy intake and therefore BMI to predict the resulting health gains in quality-adjusted life-years (QALYs) and health system costs over the remaining life course of the New Zealand population alive in 2011 (N = 4.4 million, 3% discounting). The 'base case' model (no compensation for reduced energy intake) resulted in an average reduction in SSB and energy intake of 23 ml and 44 kJ (11 kcal) per day or 0.22 kg of weight modeled over two years. The total health gain and cost-savings were 82,100 QALYs (95% UI: 65100 to 101,000) and NZ$1.65 billion [b] (95% UI: 1.19 b to 2.24 b, (US$1.10 b)) over the lifespan of the cohort. QALY gains increased to 116,000 when the SSB definition was widened to include fruit juices and sweetened milks. A cap on single serve SSB could be an effective part of a suite of obesity prevention and sugar reduction interventions in high income countries.

Potential impact of a modest reduction in salt intake on blood pressure, cardiovascular disease burden and premature mortality: a modelling study

Objective

To assess the potential impact of reduction in salt intake on the burden of cardiovascular disease (CVD) and premature mortality in Cameroon.

Methods

Using a multicohort proportional multistate life table model with Markov process, we modelled the impact of WHO's recommended 30% relative reduction in population-wide sodium intake on the CVD burden for Cameroonian adults alive in 2016. Deterministic and probabilistic sensitivity analyses were conducted and used to quantify uncertainty.

Results

Over the lifetime, incidence is predicted to decrease by 5.2% (95% uncertainty interval (UI) 4.6 to 5.7) for ischaemic heart disease (IHD), 6.6% (95% UI 5.9 to 7.4) for haemorrhagic strokes, 4.8% (95% UI 4.2 to 5.4) for ischaemic strokes and 12.9% (95% UI 12.4 to 13.5) for hypertensive heart disease (HHD). Mortality over the lifetime is projected to reduce by 5.1% (95% UI 4.5 to 5.6) for IHD, by 6.9% (95% UI 6.1 to 7.7) for haemorrhagic stroke, by 4.5% (95% UI 4.0 to 5.1) for ischaemic stroke and by 13.3% (95% UI 12.9 to 13.7) for HHD. About 776 400 (95% UI 712 600 to 841 200) health-adjusted life years could be gained, and life expectancy might increase by 0.23 years and 0.20 years for men and women, respectively. A projected 16.8% change (reduction) between 2016 and 2030 in probability of premature mortality due to CVD would occur if population salt reduction recommended by WHO is attained.

Conclusion

Achieving the 30% reduction in sodium intake recommended by WHO could considerably decrease the burden of CVD. Targeting blood pressure via decreasing population salt intake could translate in significant reductions in premature CVD mortality in Cameroon by 2030.

Comparing Strategies to Prevent Stroke and Ischemic Heart Disease in the Tunisian Population: Markov Modeling Approach Using a Comprehensive Sensitivity Analysis Algorithm

BACKGROUND

Mathematical models offer the potential to analyze and compare the effectiveness of very different interventions to prevent future cardiovascular disease. We developed a comprehensive Markov model to assess the impact of three interventions to reduce ischemic heart diseases (IHD) and stroke deaths: (i) improved medical treatments in acute phase, (ii) secondary prevention by increasing the uptake of statins, (iii) primary prevention using health promotion to reduce dietary salt consumption.

METHODS

We developed and validated a Markov model for the Tunisian population aged 35-94 years old over a 20-year time horizon. We compared the impact of specific treatments for stroke, lifestyle, and primary prevention on both IHD and stroke deaths. We then undertook extensive sensitivity analyses using both a probabilistic multivariate approach and simple linear regression (metamodeling).

RESULTS

The model forecast a dramatic mortality rise, with 111,134 IHD and stroke deaths (95% CI 106567 to 115048) predicted in 2025 in Tunisia. The salt reduction offered the potentially most powerful preventive intervention that might reduce IHD and stroke deaths by 27% (-30240 [-30580 to -29900]) compared with 1% for medical strategies and 3% for secondary prevention. The metamodeling highlighted that the initial development of a minor stroke substantially increased the subsequent probability of a fatal stroke or IHD death.

CONCLUSIONS

The primary prevention of cardiovascular disease via a reduction in dietary salt consumption appeared much more effective than secondary or tertiary prevention approaches. Our simple but comprehensive model offers a potentially attractive methodological approach that might now be extended and replicated in other contexts and populations.

Health Benefits and Cost-Effectiveness From Promoting Smartphone Apps for Weight Loss: Multistate Life Table Modeling

Background

Obesity is an important risk factor for many chronic diseases. Mobile health interventions such as smartphone apps can potentially provide a convenient low-cost addition to other obesity reduction strategies.

Objective

This study aimed to estimate the impacts on quality-adjusted life-years (QALYs) gained and health system costs over the remainder of the life span of the New Zealand population (N=4.4 million) for a smartphone app promotion intervention in 1 calendar year (2011) using currently available apps for weight loss.

Methods

The intervention was a national mass media promotion of selected smartphone apps for weight loss compared with no dedicated promotion. A multistate life table model including 14 body mass index–related diseases was used to estimate QALYs gained and health systems costs. A lifetime horizon, 3% discount rate, and health system perspective were used. The proportion of the target population receiving the intervention (1.36%) was calculated using the best evidence for the proportion who have access to smartphones, are likely to see the mass media campaign promoting the app, are likely to download a weight loss app, and are likely to continue using this app.

Results

In the base-case model, the smartphone app promotion intervention generated 29 QALYs (95% uncertainty interval, UI: 14-52) and cost the health system US $1.6 million (95% UI: 1.1-2.0 million) with the standard download rate. Under plausible assumptions, QALYs increased to 59 (95% UI: 27-107) and costs decreased to US $1.2 million (95% UI: 0.5-1.8) when standard download rates were doubled. Costs per QALY gained were US $53,600 for the standard download rate and US $20,100 when download rates were doubled. On the basis of a threshold of US $30,000 per QALY, this intervention was cost-effective for Māori when the standard download rates were increased by 50% and also for the total population when download rates were doubled.

Conclusions

In this modeling study, the mass media promotion of a smartphone app for weight loss produced relatively small health gains on a population level and was of borderline cost-effectiveness for the total population. Nevertheless, the scope for this type of intervention may expand with increasing smartphone use, more easy-to-use and effective apps becoming available, and with recommendations to use such apps being integrated into dietary counseling by health workers.

The impact of food reformulation on nutrient intakes and health, a systematic review of modelling studies

BACKGROUND

Unhealthy diet is a risk factor for adverse health outcomes. Reformulation of processed foods has the potential to improve population diet, but evidence of its impact is limited. The purpose of this review was to explore the impact of reformulation on nutrient intakes, health outcomes and quality of life; and to evaluate the quality of modelling studies on reformulation interventions.

METHODS

A systematic review of peer-reviewed articles published between January 2000 and December 2017 was performed using MEDLINE, ScienceDirect, Embase, Scopus, Cochrane, and the Centre for Reviews and Dissemination of the University of York. Additional studies were identified through informal searches on Google and specialized websites. Only simulation studies modelling the impact of food reformulation on nutrient intakes and health outcomes were included. Included articles were independently extracted by 2 reviewers using a standardized, pre-piloted data form, including a self-developed tool to assess study quality.

RESULTS

A total of 33 studies met the selected inclusion criteria, with 20, 5 and 3 studies addressing sodium, sugar and fats reformulation respectively, and 5 studies addressing multiple nutrients. Evidence on the positive effects of reformulation on consumption and health was stronger for sodium interventions, less conclusive for sugar and fats. Study features were highly heterogeneous including differences in methods, the type of policy implemented, the extent of the reformulation, and the spectrum of targeted foods and nutrients. Nonetheless, partial between-study comparisons show a consistent relationship between percentages reformulated and reductions in individual consumption. Positive results are also shown for health outcomes and quality of life measures, although comparisons across studies are limited by the heterogeneity in model features and reporting. Study quality was often compromised by short time-horizons, disregard of uncertainty and time dependencies, and lack of model validation.

CONCLUSIONS

Reformulation models highlight relevant improvements in diets and population health. While models are valuable tools to evaluate reformulation interventions, comparisons are limited by non-homogeneous designs and assumptions. The use of validated models and extensive scenario analyses would improve models' credibility, providing useful insights for policy-makers.

REVIEW REGISTRATION

A research protocol was registered within the PROSPERO database (ID number CRD42017057341).

Development of nutritional risk assessment platform in Korea

Risk assessment has been used to prevent health problems associated with eating habits in response to increased interest in a balanced diet. For nutritional risk assessment (NRA), it is important to 1) consider personal nutrition status based on year-round dietary intake, 2) organize core datasets such as food composition, intake, and health based guidance value (HBGV) datasets with public confidence, and 3) assess and predict the effects by using the computerized NRA tool. Our research staff constructed an integrated database system by compiling and organizing core datasets produced sporadically by different organizations and with different formats and developed a nutritional exposure and risk assessment system called Nutri-Risk (NUTRItional RISK assessment platform), which contained the database. Nutri-Risk is not only capable of NRA, but also contains additional data service functions. Here, the compilations and organization of an integrated database are outlined. In addition, the overall architectures of Nutri-Risk and dietary modeling are described and predictive simulation functions to support the regulatory decisions related to nutritional fortification or reduction policy were demonstrated.

Modelling impacts of food industry co-regulation on noncommunicable disease mortality, Portugal

Objective

To model the reduction in premature deaths attributed to noncommunicable diseases if targets for reformulation of processed food agreed between the Portuguese health ministry and the food industry were met.

Methods

The 2015 co-regulation agreement sets voluntary targets for reducing sugar, salt and trans-fatty acids in a range of products by 2021. We obtained government data on dietary intake in 2015–2016 and on population structure and deaths from four major noncommunicable diseases over 1990–2016. We used the Preventable Risk Integrated ModEl tool to estimate the deaths averted if reformulation targets were met in full. We projected future trends in noncommunicable disease deaths using regression modelling and assessed whether Portugal was on track to reduce baseline premature deaths from noncommunicable diseases in the year 2010 by 25% by 2025, and by 30% before 2030.

Findings

If reformulation targets were met, we projected reductions in intake in 2015–2016 for salt from 7.6 g/day to 7.1 g/day; in total energy from 1911 kcal/day to 1897 kcal/day due to reduced sugar intake; and in total fat (% total energy) from 30.4% to 30.3% due to reduced trans-fat intake. This consumption profile would result in 248 fewer premature noncommunicable disease deaths (95% CI: 178 to 318) in 2016. We projected that full implementation of the industry agreement would reduce the risk of premature death from 11.0% in 2016 to 10.7% by 2021.

Conclusion

The co-regulation agreement could save lives and reduce the risk of premature death in Portugal. Nevertheless, the projected impact on mortality was insufficient to meet international targets.

Healthcare Expenditure and Productivity Cost Savings from Reductions in Cardiovascular Disease and Type 2 Diabetes Associated with Increased Intake of Cereal Fibre among Australian Adults: A Cost of Illness Analysis

An ageing population and growing prevalence of chronic diseases including cardiovascular disease (CVD) and type 2 diabetes (T2D) are putting increased pressure on healthcare expenditure in Australia. A cost of illness analysis was conducted to assess the potential savings in healthcare expenditure and productivity costs associated with lower prevalence of CVD and T2D resulting from increased intake of cereal fibre. Modelling was undertaken for three levels of increased dietary fibre intake using cereal fibre: a 10% increase in total dietary fibre; an increase to the Adequate Intake; and an increase to the Suggested Dietary Target. Total healthcare expenditure and productivity cost savings associated with reduced CVD and T2D were calculated by gender, socioeconomic status, baseline dietary fibre intake, and population uptake. Total combined annual healthcare expenditure and productivity cost savings of AUD$17.8 million-$1.6 billion for CVD and AUD$18.2 million-$1.7 billion for T2D were calculated. Total savings were generally larger among adults of lower socioeconomic status and those with lower dietary fibre intakes. Given the substantial healthcare expenditure and productivity cost savings that could be realised through increases in cereal fibre, there is cause for the development of interventions and policies that encourage an increase in cereal fibre intake in Australia.

Identification of differences in health impact modelling of salt reduction

We examined whether specific input data and assumptions explain outcome differences in otherwise comparable health impact assessment models. Seven population health models estimating the impact of salt reduction on morbidity and mortality in western populations were compared on four sets of key features, their underlying assumptions and input data. Next, assumptions and input data were varied one by one in a default approach (the DYNAMO-HIA model) to examine how it influences the estimated health impact. Major differences in outcome were related to the size and shape of the dose-response relation between salt and blood pressure and blood pressure and disease. Modifying the effect sizes in the salt to health association resulted in the largest change in health impact estimates (33% lower), whereas other changes had less influence. Differences in health impact assessment model structure and input data may affect the health impact estimate. Therefore, clearly defined assumptions and transparent reporting for different models is crucial. However, the estimated impact of salt reduction was substantial in all of the models used, emphasizing the need for public health actions.

Cost-effectiveness of salt reduction to prevent hypertension and CVD: a systematic review

Objective

To analyse and compare the cost-effectiveness of different interventions to reduce salt consumption.

Design

A systematic review of published cost-effectiveness analyses (CEA) and cost-utility analyses (CUA) was undertaken in the databases EMBASE, MEDLINE (PubMed), Cochrane and others until July 2016. Study selection was limited to CEA and CUA conducted in member countries of the Organisation for Economic Co-operation and Development (OECD) in English, German or French, without time limit. Outcomes measures were life years gained (LYG), disability-adjusted life years (DALY) and quality-adjusted life years (QALY). Relevant aspects in modelling were analysed and compared. Quality assessments were conducted using the Drummond and Jefferson/British Medical Journalchecklist.

Setting

OECD member countries.

Subjects

Mainly adults.

Results

Fourteen CEA and CUA were included in the review which analysed different strategies: salt reduction or substitution in processed foods, taxes, labelling, awareness campaigns and targeted dietary advice. Fifty-nine out of sixty-two scenarios were cost-saving. The incremental cost-effectiveness ratio in international dollars (Intl.$; 2015) was particularly low for taxes, a salt reduction by food manufacturers and labelling (<−3072 Intl.$/QALY, −6187 Intl.$/LYG and <584 Intl.$/DALY over the time horizon compared with the status quo or no intervention). Targeted dietary advice was rather not cost-effective (24 600 Intl.$/QALY and >303 900 Intl.$/DALY). However, only six studies analysed cost-effectiveness from a societal perspective and quality assessments showed flaws in conducting and a lack of transparency in reporting.

Conclusions

A population-wide salt reduction could be cost-effective in prevention of hypertension and CVD in OECD member countries. However, comparability between study results is limited due to differences in modelling, applied perspectives and considered data.

The Science of Salt: A regularly updated systematic review of the implementation of salt reduction interventions (March-August 2016)

This review aims to identify, summarize, and appraise studies reporting on the implementation of salt reduction interventions that were published between March and August 2016. Overall, 40 studies were included: four studies evaluated the impact of salt reduction interventions, while 36 studies were identified as relevant to the design, assessment, and implementation of salt reduction strategies. Detailed appraisal and commentary were undertaken on the four studies that measured the impact of the interventions. Among them, different evaluation approaches were adopted; however, all demonstrated positive health outcomes relating to dietary salt reduction. Three of the four studies measured sodium in breads and provided consistent evidence that sodium reduction in breads is feasible and different intervention options are available. None of the studies were conducted in low- or lower middle-income countries, which stresses the need for more resources and research support for the implementation of salt reduction interventions in these countries.

Effect of 25% Sodium Reduction on Sales of a Top-Selling Bread in Remote Indigenous Australian Community Stores: A Controlled Intervention Trial

Reducing sodium in the food supply is key to achieving population salt targets, but maintaining sales is important to ensuring commercial viability and maximising clinical impact. We investigated whether 25% sodium reduction in a top-selling bread affected sales in 26 remote Indigenous community stores. After a 23-week baseline period, 11 control stores received the regular-salt bread (400 mg Na/100 g) and 15 intervention stores received the reduced-salt version (300 mg Na/100 g) for 12-weeks. Sales data were collected to examine difference between groups in change from baseline to follow-up (effect size) in sales (primary outcome) or sodium density, analysed using a mixed model. There was no significant effect on market share (-0.31%; 95% CI -0.68, 0.07; p = 0.11) or weekly dollars ($58; -149, 266; p = 0.58). Sodium density of all purchases was not significantly reduced (-8 mg Na/MJ; -18, 2; p = 0.14), but 25% reduction across all bread could significantly reduce sodium (-12; -23, -1; p = 0.03). We found 25% salt reduction in a top-selling bread did not affect sales in remote Indigenous community stores. If achieved across all breads, estimated salt intake in remote Indigenous Australian communities would be reduced by approximately 15% of the magnitude needed to achieve population salt targets, which could lead to significant health gains at the population-level.

The Eatwell Guide: Modelling the Health Implications of Incorporating New Sugar and Fibre Guidelines

OBJECTIVE

To model population health impacts of dietary changes associated with the redevelopment of the UK food-based dietary guidelines (the 'Eatwell Guide').

METHOD

Using multi-state lifetable methods, we modelled the impact of dietary changes on cardiovascular disease, diabetes and cancers over the lifetime of the current UK population. From this model, we determined change in life expectancy and disability-adjusted life years (DALYs) that could be averted.

RESULTS

Changing the average diet to that recommended in the new Eatwell Guide, without increasing total energy intake, could increase average life expectancy by 5.4 months (95% uncertainty interval: 4.7 to 6.2) for men and 4.0 months (3.4 to 4.6) for women; and avert 17.9 million (17.6 to 18.2) DALYs over the lifetime of the current population. A large proportion of the health benefits are from prevention of type 2 diabetes, with 440,000 (400,000 to 480,000) new cases prevented in men and 340,000 (310,000 to 370,000) new cases prevented in women, over the next ten years. Prevention of cardiovascular diseases and colorectal cancer is also large. However, if the diet recommended in the new Eatwell Guide is achieved with an accompanying increase in energy intake (and thus an increase in body mass index), around half the potential improvements in population health will not be realised.

CONCLUSIONS

The dietary changes required to meet recommendations in the Eatwell Guide, which include eating more fruits and vegetables and less red and processed meats and dairy products, are large. However, the potential population health benefits are substantial.