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

Dietary Salt-Related Knowledge, Attitudes, and Behaviors of New Zealand Adults Aged 18-65 Years

OBJECTIVE

To explore dietary salt-related knowledge, attitudes, and behaviors of New Zealand (NZ) adults aged 18-65 years and assess differences by demographic subgroups.

DESIGN

Cross-sectional online survey conducted between June 1, 2018 and August 31, 2018.

SETTING

Participants were recruited in shopping malls, via social media, and a market research panel.

PARTICIPANTS

English-speaking adults residing in NZ.

VARIABLES MEASURED

An amended version of The Pan American and World Health Organization Knowledge, Attitudes, and Behaviors standardized survey tool was used. Demographic data (age, sex, ethnicity, and educational attainment) were also collected.

ANALYSIS

Descriptive statistics reported. Chi-square test for independence to assess differences by demographics.

RESULTS

The survey was completed by 1,131 adults (mean age 36 ± 15 years; n = 876 [78%] female; n = 661 [78%] NZ European/other; n = 210 [19%] Asian; n =164 [15%] Māori). In addition, 865 participants (83%) knew the primary dietary source of salt; 406 (40%) knew the recommended salt intake; 946 (95%) believed food manufacturers are responsible for sodium reduction; 563 (55%) supported government regulations; and 259 (26%) used food labels. Females and NZ European/other participants reported more favorable salt-reducing behaviors, such as avoiding fast-food and packaged, ready-to-eat foods (P < 0.001).

CONCLUSIONS AND IMPLICATIONS

Improving salt-related knowledge, attitudes, and behaviors in NZ is particularly important for men, underserved populations, and adults aged 45-65 years. A multicomponent, national NZ salt reduction program based on research addressing engagement and effectiveness for at-risk groups is warranted.

Inequalities in Research on Food Environment Policies: An Evidence Map of Global Evidence from 2010-2020

There has been increasing pressure to implement policies for promoting healthy food environments worldwide. We conducted an evidence map to critically explore the breadth and nature of primary research from 2010-2020 that evaluated the effectiveness, cost-effectiveness, development, and implementation of mandatory and voluntary food environment policies. Fourteen databases and 2 websites were searched for "real-world" evaluations of international, national, and state level policies promoting healthy food environments. We documented the policy and evaluation characteristics, including the World Cancer Research Fund International NOURISHING framework's policy categories and 10 equity characteristics using the PROGRESS-Plus framework. Data were synthesized using descriptive statistics and visuals. We screened 27,958 records, of which 482 were included. Although these covered 70 countries, 81% of publications focused on only 12 countries (United States, United Kingdom, Australia, Canada, Mexico, Brazil, Chile, France, Spain, Denmark, New Zealand, and South Africa). Studies from these countries employed more robust quantitative methods and included most of the evaluations of policy development, implementation, and cost-effectiveness. Few publications reported on Africa (n = 12), Central and South Asia (n = 5), and the Middle East (n = 6) regions. Few also assessed public-private partnerships (PPPs, n = 31, 6%) compared to voluntary approaches by the private sector (n = 96, 20%), the public sector (n = 90, 19%), and mandatory approaches (n = 288, 60%). Most evaluations of PPPs reported on the same 2 partnerships. Only 50% of publications assessing policy effectiveness compared outcomes between population groups stratified by an equity characteristic, and this proportion has decreased over time. There are striking inequities in the origin, scope, and design of these studies, suggesting that research capacity and funding lies in the hands of a few expert teams worldwide. The small number of studies on PPPs questions the evidence base underlying the international push for PPPs to promote health. Policy evaluations should consider impacts on equity more consistently. This study was registered at PROSPERO as CRD42020170963.

Salt Reduction and Iodine Fortification Policies Are Compatible: Perspectives for Public Health Advocacy

Cardiovascular diseases account for almost 18 million deaths annually, the most of all non-communicable diseases. The reduction of dietary salt consumption is a modifiable risk factor. The WHO recommends a daily sodium intake of <2000 mg but average consumption exceeds this in many countries globally. Strategies proposed to aid effective salt reduction policy include product reformulation, front of pack labelling, behavioural change campaigns and establishing a low-sodium-supportive environment. Yet, salt for household and processed food use is, in countries wholly or partially adopting a universal salt iodisation policy, the principal vehicle for population-wide iodine fortification. With salt reduction policies in place, there is concern that iodine deficiency disorders may re-emerge. Recognising the urgency to tackle the rising prevalence of NCDs yet not risk the re-emergence and detrimental effect of inadequate iodine intakes, this review lays out the feasibility of integrating both salt reduction and salt iodine fortification strategies. Reducing the burden of health risks associated with an excessive sodium intake or inadequate iodine through population-tailored, cost-effective strategies involving salt is both feasible and achievable, and represents an opportunity to improve outcomes in public health.

Cost-Effectiveness of Salt Substitute and Salt Supply Restriction in Eldercare Facilities: The DECIDE-Salt Cluster Randomized Clinical Trial

Importance

Salt substitution has been reported to be a cost-saving sodium reduction strategy that has not yet been replicated in different contexts.

Objective

To estimate the cost-effectiveness of sodium reduction strategies within the DECIDE-Salt trial.

Design, Setting, and Participants

The DECIDE-Salt trial cluster randomized in a 1:1:1:1 ratio 48 eldercare facilities in China into 4 groups for evaluation of 2 sodium reduction strategies for 2 years: 1 with both strategies, 2 with either strategy, and 1 with neither strategy. The trial was conducted from September 25, 2017, through October 24, 2020.

Interventions

The 2 intervention strategies were replacing regular salt with salt substitute and progressively restricting salt supply to kitchens.

Main Outcomes and Measures

The main outcomes included per-participant costs of intervention implementation and medical treatments for hypertension and major adverse cardiovascular events (MACEs) against mean reductions in systolic blood pressure, hypertension prevalence, MACE incidence, and mortality. The incremental cost-utility ratio was then assessed as the additional mean cost per quality-adjusted life-year gained. Analyses were conducted separately for each strategy, comparing groups assigned and not assigned the test strategy. Disease outcomes followed the intention-to-treat principle and adopted different models as appropriate. One-way and probabilistic sensitivity analyses were conducted to explore uncertainty, and data analyses were performed between August 13, 2022, and April 5, 2023.

Results

A total of 1612 participants (1230 males [76.3%]) with a mean (SD) age of 71.0 (9.5) years were enrolled. Replacing regular salt with salt substitute reduced mean systolic blood pressure by 7.14 (95% CI, 3.79-10.48) mm Hg, hypertension prevalence by 5.09 (95% CI, 0.37-9.80) percentage points, and cumulative MACEs by 2.27 (95% CI, 0.09-4.45) percentage points. At the end of the 2-year intervention, the mean cost was $25.95 less for the salt substitute group than the regular salt group due to substantial savings in health care costs for MACEs (mean [SD], $72.88 [$9.11] vs $111.18 [$13.90], respectively). Sensitivity analysis showed robust cost savings. By contrast, the salt restriction strategy did not show significant results. If the salt substitution strategy were rolled out to all eldercare facilities in China, 48 101 MACEs and 107 857 hypertension cases were estimated to be averted and $54 982 278 saved in the first 2 years.

Conclusions and Relevance

The findings of this cluster randomized clinical trial indicate that salt substitution may be a cost-saving strategy for hypertension control and cardiovascular disease prevention for residents of eldercare facilities in China. The substantial health benefit savings in preventing MACEs and moderate operating costs offer strong evidence to support the Chinese government and other countries in planning or implementing sodium intake reduction and salt substitute campaigns.

Trial Registration

ClinicalTrials.gov Identifier: NCT03290716.

Effects of Behavioral Interventions for Salt Reduction on Blood Pressure and Urinary Sodium Excretion: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Hypertension is a prevalent cardiovascular condition, with excessive sodium intake being a significant risk factor. Various studies have investigated measures to reduce salt intake, including integrated lifestyle interventions and health education. However, the effectiveness of behavioral interventions focused solely on salt reduction remains unclear. This systematic review and meta-analysis aimed to investigate the effects of a behavioral intervention based on salt reduction on blood pressure and urinary sodium excretion. A comprehensive search of the Cochrane Central Register of Controlled Trials, EMBASE, PubMed, and Web of Science was conducted to identify relevant literature. Study and intervention characteristics were extracted for descriptive synthesis, and the quality of the included studies was assessed. A total of 10 studies, comprising 4,667 participants (3,796 adults and 871 children), were included. The interventions involved the provision of salt-restriction spoons or devices, salt-reduction education, self-monitoring devices for urinary sodium, and salt-reduction cooking classes. Meta-analysis results showed that behavioral interventions focused on salt reduction significantly reduced systolic blood pressure (SBP) (-1.17 mmHg; 95% CI, -1.86 to -0.49), diastolic blood pressure (DBP) (-0.58 mmHg; 95% CI, -1.07 to -0.08) and urinary sodium excretion (-21.88 mmol/24 hours; 95% CI, -32.12 to -11.64). These findings suggest that behavioral change interventions centered on salt reduction can effectively lower salt intake levels and decrease blood pressure levels. However, to enhance effectiveness, behavioral interventions for salt reduction should be combined with other salt-reduction strategies.

Economic effects of dietary salt reduction policies for cardiovascular disease prevention in Japan: a simulation study of hypothetical scenarios

Objective

Reducing dietary salt intake is an essential population strategy for cardiovascular disease (CVD) prevention, but evidence on healthcare costs and outcomes is limited in Japan. We aimed to conduct a pilot economic evaluation under hypothetical scenarios of applying the salt reduction policies of England to Japan.

Methods

We examined salt reduction policies in England: media health promotion campaigns, front-of-pack labeling, and voluntary and mandatory reformulation with best-case and worst-case policy cost scenarios. We assumed that these policies were conducted in Japan for 10 years from 2019. We used published data on epidemiology and healthcare expenditures in Japan and the costs and effects of salt reduction policies in England, and defined the benefits as a decrease in national medical expenditures on CVD. We developed a Markov cohort simulation model of the Japanese population. To estimate the annual net benefits of each policy over 10 years, we subtracted monitoring and policy costs from the benefits. We adopted a health sector perspective and a 2% discount rate.

Results

The cumulative net benefit over 10 years was largest for mandatory reformulation (best case) at 2,015.1 million USD (with costs of USD 48.3 million and benefits of USD 2063.5 million), followed by voluntary reformulation (net benefit: USD 1,895.1 million, cost: USD 48.1 million, benefit: USD 1,943.2 million), mandatory reformulation (worst case, net benefit: USD 1,447.9 million, cost: USD 1,174.5 million, benefit: USD 2,622.3 million), labeling (net benefit: USD 159.5 million, cost: USD 91.6 million, benefit: USD 251.0 million), and a media campaign (net benefit: USD 140.5 million, cost: USD 110.5 million, benefit: USD 251.0 million). There was no change in the superiority or inferiority of policies when the uncertainty of model parameters was considered.

Conclusion

Mandatory reformulation with the best-case cost scenario might be economically preferable to the other alternatives in Japan. In future research, domestic data on costs and effects of salt reduction policies should be incorporated for model refinement.

Cost-Effectiveness Analysis of Personalized Hypertension Prevention

BACKGROUND

While a population-wide strategy involving lifestyle changes and a high-risk strategy involving pharmacological interventions have been described, the recently proposed personalized medicine approach combining both strategies for the prevention of hypertension has increasingly gained attention. However, a cost-effectiveness analysis has been hardly addressed. This study was set out to build a Markov analytical decision model with a variety of prevention strategies in order to conduct an economic analysis for tailored preventative methods.

METHODS

The Markov decision model was used to perform an economic analysis of four preventative strategies: usual care, a population-based universal approach, a population-based high-risk approach, and a personalized strategy. In all decisions, the cohort in each prevention method was tracked throughout time to clarify the four-state model-based natural history of hypertension. Utilizing the Monte Carlo simulation, a probabilistic cost-effectiveness analysis was carried out. The incremental cost-effectiveness ratio was calculated to estimate the additional cost to save an additional life year.

RESULTS

The incremental cost-effectiveness ratios (ICER) for the personalized preventive strategy versus those for standard care were -USD 3317 per QALY gained, whereas they were, respectively, USD 120,781 and USD 53,223 per Quality-Adjusted Life Year (QALY) gained for the population-wide universal approach and the population-based high-risk approach. When the ceiling ratio of willingness to pay was USD 300,000, the probability of being cost-effective reached 74% for the universal approach and was almost certain for the personalized preventive strategy. The equivalent analysis for the personalized strategy against a general plan showed that the former was still cost-effective.

CONCLUSIONS

To support a health economic decision model for the financial evaluation of hypertension preventative measures, a personalized four-state natural history of hypertension model was created. The personalized preventive treatment appeared more cost-effective than population-based conventional care. These findings are extremely valuable for making hypertension-based health decisions based on precise preventive medication.

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.

Development of a short-form Chinese health literacy scale for low salt consumption (CHLSalt-22) and its validation among hypertensive patients

Background

With the accelerated pace of people’s life and the changing dietary patterns, the number of chronic diseases is increasing and occurring at a younger age in today’s society. The speedily rising hypertensive patients have become one of the main risk factors for chronic diseases. People should focus on health literacy related to salt consumption and reach a better quality of life. Currently, there is a lack of local assessment tools for low salt consumption in mainland China.

Objective

To develop a short-form version of the Chinese Health Literacy Scale For Low Salt Consumption instrument for use in mainland China.

Methods

A cross-sectional design was conducted on a sample of 1472 people in Liaoxi, China. Participants completed a sociodemographic questionnaire, the Chinese version of the CHLSalt-22, the measuring change in restriction of salt (sodium) in the diet in hypertensives (MCRSDH-SUST), the Brief Illness Perception Questionnaire (BIPQ), and the Benefit-Finding Scales (BFS) to test the hypothesis. Exploratory factor analysis and confirmatory factor analyses were performed to examine the underlying factor structure of the CHLSalt-22. One month later, 37 patients who participated in the first test were recruited to evaluate the test-retest reliability.

Results

The CHLSalt-22 demonstrated adequate internal consistency, good test-retest reliability, satisfactory construct validity, convergent validity and discriminant validity. The CHLSalt-22 count scores were correlated with age, sex, body mass index (BMI), education level, income, occupation, the Measuring Change in Restriction of Salt (sodium) in Diet in Hypertensives (MCRSDH-SUST), the Brief Illness Perception Questionnaire (BIPQ), and the Benefit-Finding Scales (BFS).

Conclusion

The results indicate that the Chinese Health Literacy Scale For Low Salt Consumption (CHLSalt-22) version has good reliability and validity and can be considered a tool to assess health literacy related to salt consumption in health screenings.

Dietary Patterns of 479 Indonesian Adults and Their Associations with Sodium and Potassium Intakes Estimated by Two 24-h Urine Collections

The excess sodium (Na) intake and insufficient potassium (K) intake are frequently observed all over the world, including Indonesia. This study explored the dietary patterns of Indonesian people and evaluated their associations with Na and K intakes. Na and K intakes were assessed by repeated 24-h urine collection. The dietary patterns of the previous month were extracted by factor analysis using the Indonesian Food Frequency Questionnaire. The participants were community-dwelling Indonesian men and women (n = 479) aged 20 years and over. We identified four dietary patterns in each sex. After controlling for confounding factors, the high quantile of ‘Noodle, oil, and salty sea products’ pattern was associated with the high Na intake in both men and women (p = 0.02 and <0.001, respectively). The ‘Meat, vegetable, oil, and fruit’ pattern statistically significantly contributed to the high K intake in men (p = 0.04), but not in women (p = 0.26). The ‘Vegetable, non-oil, and milk’ pattern in men and ‘Meat, vegetable, and fruit’ pattern in women were associated with low Na:K ratios (p = 0.03 and 0.01, respectively). Neither ‘bread’ nor ‘fish’ appeared as a major determinant of any dietary patterns in this population. The ‘Noodle, oil, and salty sea products’ pattern should be avoided to reduce sodium intake.

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.

Preliminary Experiment on the Effect of 18% Substitute Salt on Home Blood Pressure Variability in Hypertensives

At present, the effect of substitute salt in reducing sodium intake and blood pressure is relatively clear. The present study is a phase I clinical trial involving 43 hypertensives in which the effect of 18% sodium substitute salt on the home blood pressure variability (BPV) was observed for 8 weeks with weekly follow-up. Finally, 4 patients were lost, and 39 patients completed the intervention and were included in the analysis. Daily home blood pressure and weekly adverse events were collected. The systolic blood pressure (SBP) in the morning (-10.0 mmHg, 95% CI: -16.5 to -3.5, P = 0.003), SBP at night (-10.2 mmHg, 95% CI: -16.1 to -4.3, P = 0.001), and diastolic blood pressure (DBP) at night (-4.0 mmHg, 95% CI: -7.1 to -0.8, P = 0.014) decreased significantly. Also, there was no statistically significant change in morning (F = 1.137, P = 0.352) and night diastolic (F = 0.344, P = 0.481) BPV and morning systolic BPV (F = 0.663, P = 0.930) over time during the intervention period, except for that night systolic BPV had a downward trend (F = 2.778, P = 0.016) and had decreased 2.04 mmHg (95% CI: 0.84 to 3.23, P = 0.001) after intervention. The use of 18% of the substitute salt did not increase BPV during the intervention and even may decrease it, which indicates its control effects on blood pressure. This study is the first one to observe the effect of 18% sodium substitute salt on the home blood pressure variability, providing a basis for further experiments.

Protocol for the economic evaluation of the China Salt Substitute and Stroke Study (SSaSS)

INTRODUCTION

Cardiovascular diseases (CVDs) are the leading causes of death and disability worldwide. Reducing dietary salt consumption is a potentially cost-effective way to reduce blood pressure and the burden of CVD. To date, economic evidence has focused on sodium reduction in food industry or processed food with blood pressure as the primary outcome. This study protocol describes the planned within-trial economic evaluation of a low-sodium salt substitute intervention designed to reduce the risk of stroke in China.

METHODS AND ANALYSES

The economic evaluation will be conducted alongside the Salt Substitute and Stroke Study: a 5-year large scale, cluster randomised controlled trial. The outcomes of interest are quality of life measured using the EuroQol-5-Dimensions and major adverse cardiovascular events. Costs will be estimated from a healthcare system perspective and will be sought from the routinely collected data available within the New Rural Cooperative Medical Scheme. Cost-effectiveness and cost-utility analyses will be conducted, resulting in the incremental cost-effectiveness ratio expressed as cost per cardiovascular event averted and cost per quality-adjusted life year gained, respectively.

ETHICS AND DISSEMINATION

The trial received ethics approval from the University of Sydney Ethics Committee (2013/888) and Peking University Institutional Review Board (IRB00001052-13069). Informed consent was obtained from each study participant. Findings of the economic evaluation will be published in a peer-reviewed journal and presented at international conferences.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Registry (NCT02092090).

The cost-effectiveness of government actions to reduce sodium intake through salt substitutes in Vietnam

Background

Dietary sodium reduction is recommended to reduce the burden of cardiovascular disease. In Vietnam food products including salt, fish sauce and bot canh contribute to ~ 70% of dietary sodium intake. Reduced sodium versions of these products can be produced by replacing some of the sodium chloride with potassium chloride. We aimed to assess the cost-effectiveness of three alternative approaches to introducing reduced sodium products onto the market with a view to lowering population sodium intake in Vietnam.

Methods

The three salt substitution strategies included voluntary, subsidised and regulatory approaches targeting salt, fish sauce and bot canh products. Costs were modelled using the WHO-CHOICE methodology. A Markov cohort model was developed to evaluate the cost-effectiveness of each strategy versus no intervention from the government perspective. The model linked each intervention strategy to assumed changes in levels of sodium intake and then to systolic blood pressure. Changes in SBP were linked to a probability of ischaemic heart disease or stroke. The model followed people over their lifetime to assess average costs and quality adjusted life years (QALYs) gained for each strategy.

Results

The voluntary salt substitution strategy was assumed to require no investment by government. Following ramp up (years 6+), the average annual costs for the subsidised and regulatory strategies were 21,808,968,902 ₫ (US$ 977,354) and 12,949,953,247 ₫ (US$ 580,410) respectively. Relative to no intervention, all three salt substitution strategies were found to be cost-effective. Cost savings were driven by reductions in strokes (32,595; 768,384; 2,366,480) and ischaemic heart disease (IHD) events (22,830; 537,157; 1,648,590) for the voluntary, subsidised & regulatory strategies, respectively. The voluntary strategy was least cost-effective (− 3445 ₫ US$ -0.15; 0.009 QALYs gained) followed by the subsidised strategy (− 43,189 ₫ US$ -1.86; 0.022 QALYs gained) and the regulatory strategy delivered the highest cost savings and health gains (− 243,530 ₫ US$ -10.49; 0.074 QALYs gained).

Conclusion

This research shows that all three modelled salt substitution strategies would be good value for money relative to no intervention in Vietnam. The subsidised alternative would require the highest level of government investment; however the implementation costs will be exceeded by healthcare savings assuming a reasonable time horizon is considered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13690-021-00540-4.

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.

A Systematic Review of Cost-Effectiveness Studies of Interventions With a Personalized Nutrition Component in Adults

OBJECTIVES

Important links between dietary patterns and diseases have been widely applied to establish nutrition interventions. However, knowledge about between-person heterogeneity regarding the benefits of nutrition intervention can be used to personalize the intervention and thereby improve health outcomes and efficiency. We performed a systematic review of cost-effectiveness analyses (CEAs) of interventions with a personalized nutrition (PN) component to assess their methodology and findings.

METHODS

A systematic search (March 2019) was performed in 5 databases: EMBASE, Medline Ovid, Web of Science, Cochrane CENTRAL, and Google Scholar. CEAs involving interventions in adults with a PN component were included; CEAs focusing on clinical nutrition or undernutrition were excluded. The CHEERS checklist was used to assess the quality of CEAs.

RESULTS

We identified 49 eligible studies among 1792 unique records. Substantial variation in methodology was found. Most studies (91%) focused only on psychological concepts of PN such as behavior and preferences. Thirty-four CEAs were trial-based, 13 were modeling studies, and 4 studies were both trial- and model-based. Thirty-two studies used quality-adjusted life year as an outcome measure. Different time horizons, comparators, and modeling assumptions were applied, leading to differences in costs/quality-adjusted life years. Twenty-eight CEAs (49%) concluded that the intervention was cost-effective, and 75% of the incremental cost-utility ratios were cost-effective given a willingness-to-pay threshold of $50 000 per quality-adjusted life year.

CONCLUSIONS

Interventions with PN components are often evaluated using various types of models. However, most PN interventions have been considered cost-effective. More studies should examine the cost-effectiveness of PN interventions that combine psychological and biological concepts of personalization.

Estimation of salt intake assessed by 24-h urinary sodium level among adults speaking different dialects from the Chaoshan region of southern China

OBJECTIVE

Dietary salt intake may vary depending on different lifestyles. We aimed to estimate the different salt intakes and evaluate the knowledge and self-awareness about salt among people speaking the Teochew, Teochew-Hakka and Hakka dialects in the Chaoshan region of southern China.

DESIGN

The study followed a cluster sampling of residents in Chaoshan region. General characteristics, lifestyles, health status as well as knowledge and self-awareness related to salt intake were investigated using a questionnaire. Anthropometric variables as well as Na and K excretion in a 24-h urine collection were measured.

SETTING

Chaoshan region of China.

PARTICIPANTS

Four hundred fifteen adults who spoke only one of these three dialects.

RESULTS

The salt intake of adults who spoke the Teochew, Teochew-Hakka and Hakka dialects was 7·19 (interquartile range (IQR) 5·29-10·17), 9·03 (IQR 6·62-11·54) and 10·12 (IQR 7·61-12·82) g/d, respectively, with significant differences between Teochew and Teochew-Hakka speakers and between Teochew and Hakka speakers (both P < 0·05). The Na:K ratio for adults who spoke the three dialects was 3·00 (IQR 2·00-4·11), 3·50 (IQR 2·64-4·82) and 4·52 (IQR 3·35-5·97), respectively, and differed significantly among the groups (all P < 0·05). Multiple linear regression analysis showed increased Na:K ratio associated with hypertension (β = 0·71, P = 0·043) in Hakka speakers. Knowledge and self-awareness about salt intake were poor in this population.

CONCLUSIONS

Salt intake was closely related to lifestyles and was higher than the upper limit (5 g/d) recommended by the WHO in adults of Chaoshan, especially those speaking the Hakka dialect.

The role of dietary salt and alcohol use reduction in the management of hypertension

Introduction: Despite the improved treatment protocol of hypertension, the magnitude of the disease and its related burden remains raised. Hypertension makes up the leading cause of stroke, kidney disease, arterial disease, eye disease, and cardiovascular disease (CVD) growth. Areas covered: This review provides the overview of the role of dietary salt and alcohol use reduction in the management of hypertension, a brief history of alcohol, the vascular endothelium functions, the effects of alcohol use on blood pressure (BP), the mechanisms of alcohol, brief history of salt, the effects of dietary salt intake on BP, and the mechanisms of salt. Expert opinion: Studies found that high dietary salt intake and heavy alcohol consumption have a major and huge impact on BP while both of them have been identified to increase BP. Also, they raise the risk of hypertension-related morbidity and mortality in advance. On the other way, the dietary salt and alcohol use reduction in the management of hypertension are significant in the control of BP and its related morbidity and mortality. Further, studies suggested that the dietary salt and alcohol use reductions are the cornerstone in the management of hypertension due to their significance as part of comprehensive lifestyle modifications.

Systematic Review on International Salt Reduction Policy in Restaurants

As the catering sector has increasingly contributed to population-level salt intake, many countries have begun developing salt-reduction strategies for restaurants. This paper aims to provide an overview of global salt reduction policies in restaurants. Scientific papers and website materials were systematically searched from Web of Science, Science Direct, and PubMed, as well as official websites of government departments and organizations. A total of 78 full-text papers and grey literature works were included. From 58 countries and regions, 62 independent policies were identified, 27 of which were mandatory (3 with fines). The most common strategy was menu labeling, which was a component of 40 policies. Target setting (n = 23) and reformulation (n = 13) of dishes were also widely implemented. Other salt-reduction strategies included education campaign, chef training, toolkits delivery, table salt removal, media campaign, and government assistance such as free nutrition analysis and toolkits distribution. Most policies focused on chain restaurants. Evaluations of these policies were limited and showed inconsistent results, and more time is needed to demonstrate the clear long-term effects. Attention has been paid to salt reduction in restaurants around the world but is still at its early stage. The feasibility and effectiveness of the strategies need to be further explored.

Gender differences and determinants of prevalence, awareness, treatment and control of hypertension among adults in China and Sweden

Background

Failure to promote early detection and better management of hypertension will contribute to the increasing burden of cardiovascular diseases. This study aims to assess the gender differences in the prevalence, awareness, treatment and control of hypertension, together with its associated factors, in China and Sweden.

Methods

We used data from two cross-sectional studies: the Västerbotten Intervention Program in northern Sweden (n = 25,511) and the Shanghai survey in eastern China (n = 25,356). We employed multivariable logistic regression to examine the socio-demographics, lifestyle behaviours, and biological factors associated with the prevalence, awareness, treatment and control of hypertension.

Results

Men had a higher prevalence of hypertension (43% in Sweden, 39% in China) than their female counterparts (29 and 36%, respectively). In Sweden, men were less aware of, less treated for, and had less control over their hypertension than women. Chinese men were more aware of, had similar levels of treatment for, and had less control over their hypertension compared to women. Awareness and control of hypertension was lower in China compared to Sweden. Only 33 and 38% of hypertensive Chinese men and women who were treated reached the treatment goals, compared with a respective 48 and 59% in Sweden. Old age, impaired glucose tolerance or diabetes, a family history of hypertension or cardiovascular diseases, low physical activity and overweight or obesity were found to increase the odds of hypertension and its diagnosis.

Conclusions

This study shows the age and gender differences in the prevalence, awareness, treatment and control of hypertension among adults in China and Sweden. Multisectoral intervention should be developed to address the increasing burden of sedentary lifestyle, overweight and obesity and diabetes, all of which are linked to the prevention and control of hypertension. Development and implementation of the gender- and context-specific intervention for the prevention and control of hypertension facilitates understanding with regard to the implementation barriers and facilitators.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-020-09862-4.

Effectiveness and Feasibility of Taxing Salt and Foods High in Sodium: A Systematic Review of the Evidence

Diets high in salt are a leading risk for death and disability globally. Taxing unhealthy food is an effective means of influencing what people eat and improving population health. Although there is a growing body of evidence on taxing products high in sugar, and unhealthy foods more broadly, there is limited knowledge or experience of using fiscal measures to reduce salt consumption. We searched peer-reviewed databases [MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and the Cochrane Database of Systematic Reviews] and gray literature for studies published between January 2000 and October 2019. Studies were included if they provided information on the impact on salt consumption of: taxes on salt; taxes on foods high in salt, and taxes on unhealthy foods defined to include foods high in salt. Studies were excluded if their definition of unhealthy foods did not specify high salt or sodium. We found 18 relevant studies, including 15 studies reporting the effects of salt taxes through modeling (8), real-world evaluation (4), experimental design (2), or review of cost-effectiveness (1); 6 studies providing information relevant to country implementation of salt taxes; and 2 studies reporting stakeholder perceptions toward salt taxation. Although there is some evidence on the potential effectiveness and cost-effectiveness of salt taxation, especially from modeling studies, uptake of salt taxation is limited in practice. Some modeling studies suggested that food taxes can have unintended outcomes such as reduced consumption of healthy foods, or increased consumption of unhealthy, untaxed substitutes. In contrast, modeling studies that combined taxes for unhealthy foods with subsidies found that the benefits were increased. Modeling suggests that taxing all foods based on their salt content is likely to have more impact than taxing specific products high in salt given that salt is pervasive in the food chain. However, the limited experience we found suggests that policy-makers favor taxing specific products.

Curtis C, Frieden TR, Cobb LK. Priority Actions to Advance Population Sodium Reduction

High sodium intake is estimated to cause approximately 3 million deaths per year worldwide. The estimated average sodium intake of 3.95 g/day far exceeds the recommended intake. Population sodium reduction should be a global priority, while simultaneously ensuring universal salt iodization. This article identifies high priority strategies that address major sources of sodium: added to packaged food, added to food consumed outside the home, and added in the home. To be included, strategies needed to be scalable and sustainable, have large benefit, and applicable to one of four measures of effectiveness: (1) Rigorously evaluated with demonstrated success in reducing sodium; (2) suggestive evidence from lower quality evaluations or modeling; (3) rigorous evaluations of similar interventions not specifically for sodium reduction; or (4) an innovative approach for sources of sodium that are not sufficiently addressed by an existing strategy. We identified seven priority interventions. Four target packaged food: front-of-pack labeling, packaged food reformulation targets, regulating food marketing to children, and taxes on high sodium foods. One targets food consumed outside the home: food procurement policies for public institutions. Two target sodium added at home: mass media campaigns and population uptake of low-sodium salt. In conclusion, governments have many tools to save lives by reducing population sodium intake.

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.

Innovative Implementation Strategies for Hypertension Control in Low- and Middle-Income Countries: a Narrative Review

PURPOSE OF REVIEW

This review summarizes the most recent and innovative implementation strategies for hypertension control in low- and middle-income countries (LMICs).

RECENT FINDINGS

Implementation strategies from Latin America, Africa, and Asia were organized across three levels: community, health system, and policy/population. Multicomponent interventions involving task-shifting strategies, with or without mobile health tools, had the most supporting evidence, with policy or population-level interventions having the least, focused only on salt reduction with mixed results. More research is needed to better understand how context affects intervention implementation. There is an emerging evidence base for implementation strategies for hypertension control and CVD risk reduction in LMICs at the community and health system levels, but further research is needed to determine the most effective policy and population-level strategies. How to best account for local context in adapting and implementing these evidence-based interventions in LMICs still remains largely unknown. Accelerating the translation of this implementation research into policy and practice is imperative to improve health and save lives globally.

Can cost-effectiveness results be combined into a coherent league table? Case study from one high-income country

BACKGROUND

Doubts exist around the value of compiling league tables for cost-effectiveness results for health interventions, primarily due to methods differences. We aimed to determine if a reasonably coherent league table could be compiled using published studies for one high-income country: New Zealand (NZ).

METHODS

Literature searches were conducted to identify NZ-relevant studies published in the peer-reviewed journal literature between 1 January 2010 and 8 October 2017. Only studies with the following metrics were included: cost per quality-adjusted life-year or disability-adjusted life-year or life-year (QALY/DALY/LY). Key study features were abstracted and a summary league table produced which classified the studies in terms of cost-effectiveness.

RESULTS

A total of 21 cost-effectiveness studies which met the inclusion criteria were identified. There were some large methodological differences between the studies, particularly in the time horizon (1 year to lifetime) but also discount rates (range 0 to 10%). Nevertheless, we were able to group the incremental cost-effectiveness ratios (ICERs) into general categories of being reported as cost-saving (19%), cost-effective (71%), and not cost-effective (10%). The median ICER (adjusted to 2017 NZ$) was ~ $5000 per QALY/DALY/LY (~US$3500). However, for some interventions, there is high uncertainty around the intervention effectiveness and declining adherence over time.

CONCLUSIONS

It seemed possible to produce a reasonably coherent league table for the ICER values from different studies (within broad groupings) in this high-income country. Most interventions were cost-effective and a fifth were cost-saving. Nevertheless, study methodologies did vary widely and researchers need to pay more attention to using standardised methods that allow their results to be included in future league tables.

A self-monitoring urinary salt excretion level measurement device for educating young women about salt reduction: A parallel randomized trial involving two groups

To prevent and treat hypertension, it is important to restrict salt in one's diet since adolescence. However, an effective salt-reduction education system has yet to be established. Besides accurate evaluation, we believe that the frequent usage of a measurement device may motivate individuals to avoid high salt intake. The present study evaluated the use of a urinary salt excretion measurement device for salt-reduction education in a parallel randomized trial of two groups. The sample comprised 100 university students who provided consent to participate. A survey with 24-hour home urine collection and blood pressure measurement was conducted. Participants in the self-monitoring group measured their own urinary salt excretion level for 4 weeks, using the self-measurement device. Analyses were conducted on 51 participants in the control group and 49 in the self-monitoring group. At baseline, there was no significant difference between the two groups in terms of their characteristics and 24-hour urinary salt excretion levels. After intervention, 24-hour urinary sodium/potassium ratio showed no change in the control group [baseline score: 4.1 ± 1.5; endline score: 4.2 ± 2.0; P = 0.723], but it decreased significantly in the self-monitoring group [baseline score: 4.0 ± 1.7; endline score: 3.5 ± 1.4; P = 0.044]. This change was significant even after adjusting for baseline and endline differences between groups using analysis of covariance (P = 0.045). The self-monitoring urinary salt excretion measurement device improved the 24-hour urinary sodium/potassium ratio. The device is a useful and practical tool for educating young individuals about dietary salt reduction.

Salt-Related Knowledge, Attitudes, and Behaviors on Efate Island, Vanuatu

In Vanuatu, mean salt intake exceeds the recommended maximum daily intake, and contributes to the high proportion of deaths attributable to cardiovascular diseases. Understanding salt-related knowledge, attitudes, and behaviors of the Vanuatu population can inform appropriate interventions. This cross-sectional study was conducted as part of the 2016–2017 Vanuatu Salt Survey. In total, 753 participants aged between 18 and 69 years from rural and urban communities on the Island of Efate were included. Demographic and clinical data were collected and a salt-related knowledge, attitudes, and behaviors survey was administered. Knowledge relating to the need to reduce salt consumption was high, but reported behaviors did not reflect this knowledge. A total of 83% of participants agreed that too much salt could cause health problems, and 86% reported that it was “very important” to lower the amount of salt in the diet. However, more than two-thirds of the population reported always/often adding salt to food during cooking/meal preparation and at the table, and always/often consuming processed foods high in salt. Strategic, targeted, and sustained behavior change programs in parallel with interventions to change the food environment to facilitate healthier choices should be key components of a salt reduction program. Actions should implemented as part of a comprehensive strategy to prevent and control non-communicable diseases in Vanuatu.

Sodium Levels of Processed Meat in Australia: Supermarket Survey Data from 2010 to 2017

High sodium intake increases blood pressure and consequently increases the risk of cardiovascular diseases. In Australia, the best estimate of sodium intake is 3840 mg sodium/day, almost double the World Health Organization (WHO) guideline (2000 mg/day), and processed meats contribute approximately 10% of daily sodium intake to the diet. This study assessed the median sodium levels of 2510 processed meat products, including bacon and sausages, available in major Australian supermarkets in 2010, 2013, 2015 and 2017, and assessed changes over time. The median sodium content of processed meats in 2017 was 775 mg/100 g (interquartile range (IQR) 483⁻1080). There was an 11% reduction in the median sodium level of processed meats for which targets were set under the government's Food and Health Dialogue (p < 0.001). This includes bacon, ham/cured meat products, sliced luncheon meat and meat with pastry categories. There was no change in processed meats without a target (median difference 6%, p = 0.450). The new targets proposed by the current government's Healthy Food Partnership capture a larger proportion of products than the Food and Health Dialogue (66% compared to 35%) and a lower proportion of products are at or below the target (35% compared to 54%). These results demonstrate that voluntary government targets can drive nutrient reformulation. Future efforts will require strong government leadership and robust monitoring and evaluation systems.