Salt Reduction Initiatives around the World - A Systematic Review of Progress towards the Global Target

How is Indonesia coping with its epidemic of chronic noncommunicable diseases? A systematic review with meta-analysis

BACKGROUND

Chronic noncommunicable diseases (NCDs) have emerged as a huge global health problem in low- and middle-income countries. The magnitude of the rise of NCDs is particularly visible in Southeast Asia where limited resources have been used to address this rising epidemic, as in the case of Indonesia. Robust evidence to measure growing NCD-related burdens at national and local levels and to aid national discussion on social determinants of health and intra-country inequalities is needed. The aim of this review is (i) to illustrate the burden of risk factors, morbidity, disability, and mortality related to NCDs; (ii) to identify existing policy and community interventions, including disease prevention and management strategies; and (iii) to investigate how and why an inequitable distribution of this burden can be explained in terms of the social determinants of health.

METHODS

Our review followed the PRISMA guidelines for identifying, screening, and checking the eligibility and quality of relevant literature. We systematically searched electronic databases and gray literature for English- and Indonesian-language studies published between Jan 1, 2000 and October 1, 2015. We synthesized included studies in the form of a narrative synthesis and where possible meta-analyzed their data.

RESULTS

On the basis of deductive qualitative content analysis, 130 included citations were grouped into seven topic areas: risk factors; morbidity; disability; mortality; disease management; interventions and prevention; and social determinants of health. A quantitative synthesis meta-analyzed a subset of studies related to the risk factors smoking, obesity, and hypertension.

CONCLUSIONS

Our findings echo the urgent need to expand routine risk factor surveillance and outcome monitoring and to integrate these into one national health information system. There is a stringent necessity to reorient and enhance health system responses to offer effective, realistic, and affordable ways to prevent and control NCDs through cost-effective interventions and a more structured approach to the delivery of high-quality primary care and equitable prevention and treatment strategies. Research on social determinants of health and policy-relevant research need to be expanded and strengthened to the extent that a reduction of the total NCD burden and inequalities therein should be treated as related and mutually reinforcing priorities.

Food formulation and not processing level: Conceptual divergences between public health and food science and technology sectors

Observed changes in eating and drinking behaviors in economically developing countries are associated with increase of obesity and related chronic diseases. Researchers from field of public health (PH) have attributed this problem to food processing and have created new food classification systems to support their thesis. These classifications conceptually differ from processing level concepts in food science, and state to people that food processing is directly related to nutritional impact of food. Our work aims to compare the concept of food processing from the standpoint of food science and technology (FST) and public health and to discuss differences related to formulation or level of processing of products and their impact on nutritional quality. There is a misconception between food processing/unit operation/food technology and formulation or recipes. For the public health approach, classification is based on food products selection and the use of ingredients that results in higher consumption of sugar, sodium, fat, and additives, whereas in FST, processing level is based on the intensity and amount of unit operations to enhance shelf life, food safety, food quality, and availability of edible parts of raw materials. Nutritional quality of a product or preparation is associated with formulation/recipe and not with the level of processing, with few exceptions. The impact of these recommendations on the actual comprehension of food processing and quality must be considered by the population.

Rationale, design, and baseline characteristics of the Salt Substitute and Stroke Study (SSaSS)-A large-scale cluster randomized controlled trial

Lowering sodium intake with a reduced-sodium, added potassium salt substitute has been proved to lower blood pressure levels. Whether the same strategy will also reduce the risks of vascular outcomes is uncertain and controversial. The SSaSS has been designed to test whether sodium reduction achieved with a salt substitute can reduce the risk of vascular disease. The study is a large-scale, open, cluster-randomized controlled trial done in 600 villages across 5 provinces in China. Participants have either a history of stroke or an elevated risk of stroke based on age and blood pressure level at entry. Villages were randomized in a 1:1 ratio to intervention or continued usual care. Salt substitute is provided free of charge to participants in villages assigned to the intervention group. Follow-up is scheduled every 6months for 5years, and all potential endpoints are reviewed by a masked adjudication committee. The primary end point is fatal and nonfatal stroke, and the 2 secondary endpoints are total major cardiovascular events and total mortality. The study has been designed to provide 90% statistical power (with 2-sided α = .05) to detect a 13% or greater relative risk reduction for stroke. The power estimate assumes a primary outcome event rate of 3.5% per year and a systolic blood pressure difference of 3.0mm Hg between randomized groups. Recruitment is complete and there are 20,996 participants (about 35 per village) that have been enrolled. Mean age is 65years and 49% are female. There were 73% enrolled on the basis of a history of stroke. The trial is well placed to describe the effects of salt substitution on the risks of vascular disease and death and will provide important policy-relevant data.

Knowledge, attitudes and behaviours related to dietary salt among adults in the state of Victoria, Australia 2015

Background

Information on consumer’s knowledge, attitudes and behaviours (KABs) related to salt can be used to inform awareness and education campaigns and serve as a baseline measure to monitor changes in KABs over time. The aim of this study was to determine KABs related to salt intake among Victorian adults.

Methods

Cross-sectional survey conducted in Victorian adults aged 18–65 years. Participants were recruited from shopping centres located in Melbourne and Geelong and via online methods (Facebook and Consumer Research Panel) to complete an online survey assessing KABs related to dietary salt. Descriptive statistics (mean (SD) or n (%)) were used to report survey findings.

Results

A total of 2398 participants provided a valid survey (mean age 43 years (SD 13), 57% female). The majority (80%) were born in Australia and 63% were the main household grocery shopper. The majority (89%) were aware of the health risks associated with a high salt intake. Eighty three percent believed that Australians eat too much salt. Three quarters (75%) correctly identified salt from processed foods as being the main source of salt in the diet. Less than a third (29%) of participants believed their own individual salt intake exceeded dietary recommendations and only 28% could correctly identify the maximum recommended daily intake for salt. Just under half (46%) of participants were concerned about the amount of salt in food. Almost two thirds (61%) of participants believed that there should be laws which limit the amount of salt added to manufactured foods and 58% agreed that it was difficult to find lower salt options when eating out.

Conclusions

The findings of this study serve as a baseline assessment of KABs related to salt intake in Victorian adults and can be used to assess changes in salt related KABs over time. Public concern about salt is low as many people remain unaware of their own salt intake. An increased awareness of the excessive amount of salt consumed and increased availability of lower salt foods are likely to reduce population salt intake.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-017-4451-0) contains supplementary material, which is available to authorized users.

Systematic review of dietary salt reduction policies: Evidence for an effectiveness hierarchy?

BACKGROUND

Non-communicable disease (NCD) prevention strategies now prioritise four major risk factors: food, tobacco, alcohol and physical activity. Dietary salt intake remains much higher than recommended, increasing blood pressure, cardiovascular disease and stomach cancer. Substantial reductions in salt intake are therefore urgently needed. However, the debate continues about the most effective approaches. To inform future prevention programmes, we systematically reviewed the evidence on the effectiveness of possible salt reduction interventions. We further compared "downstream, agentic" approaches targeting individuals with "upstream, structural" policy-based population strategies.

METHODS

We searched six electronic databases (CDSR, CRD, MEDLINE, SCI, SCOPUS and the Campbell Library) using a pre-piloted search strategy focussing on the effectiveness of population interventions to reduce salt intake. Retrieved papers were independently screened, appraised and graded for quality by two researchers. To facilitate comparisons between the interventions, the extracted data were categorised using nine stages along the agentic/structural continuum, from "downstream": dietary counselling (for individuals, worksites or communities), through media campaigns, nutrition labelling, voluntary and mandatory reformulation, to the most "upstream" regulatory and fiscal interventions, and comprehensive strategies involving multiple components.

RESULTS

After screening 2,526 candidate papers, 70 were included in this systematic review (49 empirical studies and 21 modelling studies). Some papers described several interventions. Quality was variable. Multi-component strategies involving both upstream and downstream interventions, generally achieved the biggest reductions in salt consumption across an entire population, most notably 4g/day in Finland and Japan, 3g/day in Turkey and 1.3g/day recently in the UK. Mandatory reformulation alone could achieve a reduction of approximately 1.45g/day (three separate studies), followed by voluntary reformulation (-0.8g/day), school interventions (-0.7g/day), short term dietary advice (-0.6g/day) and nutrition labelling (-0.4g/day), but each with a wide range. Tax and community based counselling could, each typically reduce salt intake by 0.3g/day, whilst even smaller population benefits were derived from health education media campaigns (-0.1g/day). Worksite interventions achieved an increase in intake (+0.5g/day), however, with a very wide range. Long term dietary advice could achieve a -2g/day reduction under optimal research trial conditions; however, smaller reductions might be anticipated in unselected individuals.

CONCLUSIONS

Comprehensive strategies involving multiple components (reformulation, food labelling and media campaigns) and "upstream" population-wide policies such as mandatory reformulation generally appear to achieve larger reductions in population-wide salt consumption than "downstream", individually focussed interventions. This 'effectiveness hierarchy' might deserve greater emphasis in future NCD prevention strategies.

The Sodium Content of Processed Foods in South Africa during the Introduction of Mandatory Sodium Limits

Background: In June 2016, the Republic of South Africa introduced legislation for mandatory limits for the upper sodium content permitted in a wide range of processed foods. We assessed the sodium levels of packaged foods in South Africa during the one-year period leading up to the mandatory implementation date of the legislation. Methods: Data on the nutritional composition of packaged foods was obtained from nutrition information panels on food labels through both in-store surveys and crowdsourcing by users of the HealthyFood Switch mobile phone app between June 2015 and August 2016. Summary sodium levels were calculated for 15 food categories, including the 13 categories covered by the sodium legislation. The percentage of foods that met the government’s 2016 sodium limits was also calculated. Results: 11,065 processed food items were included in the analyses; 1851 of these were subject to the sodium legislation. Overall, 67% of targeted foods had a sodium level at or below the legislated limit. Categories with the lowest percentage of foods that met legislated limits were bread (27%), potato crisps (41%), salt and vinegar flavoured snacks (42%), and raw processed sausages (45%). About half (49%) of targeted foods not meeting the legislated limits were less than 25% above the maximum sodium level. Conclusion: Sodium levels in two-thirds of foods covered by the South African sodium legislation were at or below the permitted upper levels at the mandatory implementation date of the legislation and many more were close to the limit. The South African food industry has an excellent opportunity to rapidly meet the legislated requirements.

A systematic review of economic evaluations of population-based sodium reduction interventions

OBJECTIVE

To summarise evidence describing the cost-effectiveness of population-based interventions targeting sodium reduction.

METHODS

A systematic search of published and grey literature databases and websites was conducted using specified key words. Characteristics of identified economic evaluations were recorded, and included studies were appraised for reporting quality using the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) checklist.

RESULTS

Twenty studies met the study inclusion criteria and received a full paper review. Fourteen studies were identified as full economic evaluations in that they included both costs and benefits associated with an intervention measured against a comparator. Most studies were modelling exercises based on scenarios for achieving salt reduction and assumed effects on health outcomes. All 14 studies concluded that their specified intervention(s) targeting reductions in population sodium consumption were cost-effective, and in the majority of cases, were cost saving. Just over half the studies (8/14) were assessed as being of 'excellent' reporting quality, five studies fell into the 'very good' quality category and one into the 'good' category. All of the identified evaluations were based on modelling, whereby inputs for all the key parameters including the effect size were either drawn from published datasets, existing literature or based on expert advice.

CONCLUSION

Despite a clear increase in evaluations of salt reduction programs in recent years, this review identified relatively few economic evaluations of population salt reduction interventions. None of the studies were based on actual implementation of intervention(s) and the associated collection of new empirical data. The studies universally showed that population-based salt reduction strategies are likely to be cost effective or cost saving. However, given the reliance on modelling, there is a need for the effectiveness of new interventions to be evaluated in the field using strong study designs and parallel economic evaluations.

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.

Review of behaviour change interventions to reduce population salt intake

Background

Excess salt intake is a major cause of raised blood pressure—the leading risk factor for death and disability worldwide. Although behaviour change interventions such as awareness campaigns and health education programs are implemented to reduce salt intake, their effectiveness is unclear. This global systematic review investigates the impact of population-level behaviour change interventions that aim to reduce salt intake.

Methods

A search for published and grey literature was conducted using PubMed, Cochrane Library, Embase, Web of Science, Sage, Scopus, OpenGrey, Google Scholar and other relevant organizations’ websites. Studies were included if 1) published between 2005 and 2015; 2) the education or awareness-raising interventions were aimed at the population or sub-population and 3) salt intake and/or salt-related behaviours were outcome measures. Study and intervention characteristics were extracted for the descriptive synthesis and study quality was assessed.

Results

Twenty two studies involving 41,448 participants were included. Most were conducted in high income countries (n = 16), targeting adults (n = 21) in the general population (n = 16). Behaviour change interventions were categorised as health education interventions (n = 14), public awareness campaigns (n = 4) and multi-component interventions (including both health education and awareness campaigns, n = 4). 19 of the 22 studies demonstrated significant reductions in estimated salt intake and/or improvement in salt-related behaviours. All studies showed high risk of bias in one or more domains. Of the 10 higher quality studies, 5 found a significant effect on salt intake or salt behaviours based on the more objective outcome assessment method.

Conclusion

Based on moderate quality of evidence, population-level behaviour change interventions can improve salt-related behaviours and/or reduce salt intake. However, closer analysis of higher quality studies show inconsistent evidence of the effectiveness and limited effect sizes suggest the implementation of education and awareness-raising interventions alone are unlikely to be adequate in reducing population salt intake to the recommended levels. A framework which guides rigorous research and evaluation of population-level interventions in real-world settings would help understand and support more effective implementation of interventions to reduce salt intake.

Innovative Approaches to Hypertension Control in Low- and Middle-Income Countries

Elevated blood pressure, a major risk factor for ischemic heart disease, heart failure, and stroke, is the leading global risk for mortality. Treatment and control rates are very low in low- and middle-income countries. There is an urgent need to address this problem. The Global Alliance for Chronic Diseases sponsored research projects focus on controlling hypertension, including community engagement, salt reduction, salt substitution, task redistribution, mHealth, and fixed-dose combination therapies. This paper reviews the rationale for each approach and summarizes the experience of some of the research teams. The studies demonstrate innovative and practical methods for improving hypertension control.

Estimated reductions in cardiovascular and gastric cancer disease burden through salt policies in England: an IMPACTNCD microsimulation study

OBJECTIVE

To estimate the impact and equity of existing and potential UK salt reduction policies on primary prevention of cardiovascular disease (CVD) and gastric cancer (GCa) in England.

DESIGN

A microsimulation study of a close-to-reality synthetic population. In the first period, 2003-2015, we compared the impact of current policy against a counterfactual 'no intervention' scenario, which assumed salt consumption persisted at 2003 levels. For 2016-2030, we assumed additional legislative policies could achieve a steeper salt decline and we compared this against the counterfactual scenario that the downward trend in salt consumption observed between 2001 and 2011 would continue up to 2030.

SETTING

Synthetic population with similar characteristics to the non-institutionalised population of England.

PARTICIPANTS

Synthetic individuals with traits informed by the Health Survey for England.

MAIN MEASURE

CVD and GCa cases and deaths prevented or postponed, stratified by fifths of socioeconomic status using the Index of Multiple Deprivation.

RESULTS

Since 2003, current salt policies have prevented or postponed ∼52 000 CVD cases (IQR: 34 000-76 000) and 10 000 CVD deaths (IQR: 3000-17 000). In addition, the current policies have prevented ∼5000 new cases of GCa (IQR: 2000-7000) resulting in about 2000 fewer deaths (IQR: 0-4000). This policy did not reduce socioeconomic inequalities in CVD, and likely increased inequalities in GCa. Additional legislative policies from 2016 could further prevent or postpone ∼19 000 CVD cases (IQR: 8000-30 000) and 3600 deaths by 2030 (IQR: -400-8100) and may reduce inequalities. Similarly for GCa, 1200 cases (IQR: -200-3000) and 700 deaths (IQR: -900-2300) could be prevented or postponed with a neutral impact on inequalities.

CONCLUSIONS

Current salt reduction policies are powerfully effective in reducing the CVD and GCa burdens overall but fail to reduce the inequalities involved. Additional structural policies could achieve further, more equitable health benefits.

Inadequate dietary intake of minerals: prevalence and association with socio-demographic and lifestyle factors

This cross-sectional, population-based study aimed to estimate the prevalence of dietary mineral inadequacies among residents in urban areas of Sao Paulo, to identify foods contributing to mineral intake and to verify possible associations between socio-demographic and lifestyle factors and mineral intake. Data were obtained from the 2008 Health Survey of Sao Paulo (n 1511; mean age 43·6 (sd 23·2), range 14–97 years). Dietary intake of minerals was measured using two 24-h dietary recalls. Socio-demographic and lifestyle data were collected. The prevalence of inadequate intake was estimated according to Dietary Reference Intakes methods. Associations between mineral intake and baseline factors were determined using multiple linear regression. Na, Ca and Mg showed the highest dietary inadequacies. Some age/sex groups had lower intakes of P, Zn, Cu and Se. Rice, beans and bread were the main foods contributing towards mineral intake. Female sex was negatively associated with K, Na, P, Mg, Zn and Mn intakes. All age groups were positively associated with the intakes of K, P, Mg and Mn. Family income above one minimum wage was positively associated with Se intake. Living in a household whose head completed ≥10 years of education was positively associated with Ca and negatively associated with Na intake. Former smoker status was negatively associated with Ca intake. Current smoker status was inversely associated with K, Ca, P and Cu intakes. Sufficient physical activity was positively associated with K, Ca and Mg intakes. Overall, the intakes of all major minerals were inadequate and were influenced by socio-demographic and lifestyle factors.

Cost effectiveness of a government supported policy strategy to decrease sodium intake: global analysis across 183 nations

OBJECTIVE

 To quantify the cost effectiveness of a government policy combining targeted industry agreements and public education to reduce sodium intake in 183 countries worldwide.

DESIGN

 Global modeling study.

SETTING

 183 countries.

POPULATION

 Full adult population in each country.

INTERVENTION

 A "soft regulation" national policy that combines targeted industry agreements, government monitoring, and public education to reduce population sodium intake, modeled on the recent successful UK program. To account for heterogeneity in efficacy across countries, a range of scenarios were evaluated, including 10%, 30%, 0.5 g/day, and 1.5 g/day sodium reductions achieved over 10 years. We characterized global sodium intakes, blood pressure levels, effects of sodium on blood pressure and of blood pressure on cardiovascular disease, and cardiovascular disease rates in 2010, each by age and sex, in 183 countries. Country specific costs of a sodium reduction policy were estimated using the World Health Organization Noncommunicable Disease Costing Tool. Country specific impacts on mortality and disability adjusted life years (DALYs) were modeled using comparative risk assessment. We only evaluated program costs, without incorporating potential healthcare savings from prevented events, to provide conservative estimates of cost effectiveness MAIN OUTCOME MEASURE:  Cost effectiveness ratio, evaluated as purchasing power parity adjusted international dollars (equivalent to the country specific purchasing power of US$) per DALY saved over 10 years.

RESULTS

 Worldwide, a 10% reduction in sodium consumption over 10 years within each country was projected to avert approximately 5.8 million DALYs/year related to cardiovascular diseases, at a population weighted mean cost of I$1.13 per capita over the 10 year intervention. The population weighted mean cost effectiveness ratio was approximately I$204/DALY. Across nine world regions, estimated cost effectiveness of sodium reduction was best in South Asia (I$116/DALY); across the world's 30 most populous countries, best in Uzbekistan (I$26.08/DALY) and Myanmar (I$33.30/DALY). Cost effectiveness was lowest in Australia/New Zealand (I$880/DALY, or 0.02×gross domestic product (GDP) per capita), although still substantially better than standard thresholds for cost effective (<3.0×GDP per capita) or highly cost effective (<1.0×GDP per capita) interventions. Most (96.0%) of the world's adult population lived in countries in which this intervention had a cost effectiveness ratio <0.1×GDP per capita, and 99.6% in countries with a cost effectiveness ratio <1.0×GDP per capita.

CONCLUSION

 A government "soft regulation" strategy combining targeted industry agreements and public education to reduce dietary sodium is projected to be highly cost effective worldwide, even without accounting for potential healthcare savings.

Knowledge, attitudes and perception on dietary salt reduction of two communities in Grahamstown, South Africa

INTRODUCTION

Dietary salt reduction has been identified as a cost effective way of addressing the global burden of non-communicable diseases (NCDs), particularly cardiovascular diseases. The World Health Organization has recommended three main strategies for achieving population-wide salt reduction in all member states: food reformulation, policies and consumer awareness campaigns. In 2013, the South African Ministry of Health announced the mandatory salt reduction legislation for the food manufacturing sector. These were set to come into effect on 30 June 2016. This decision was influenced by the need to reduce the incidence of NCDs and the fact that processed food is the source of 54% of the salt consumed in the South African diet. However, with discretionary salt also being a significant contributor, there is need for consumer awareness campaigns. The aim of this study was to assess the knowledge, attitudes and practices of guardians and cooks at two non-governmental organisations based in Grahamstown, South Africa, towards dietary salt reduction.

METHOD

Data was collected through observation and explorative, voice-recorded semi-structured interviews and transcribed data was analysed using NVivo®.

RESULTS

At both centres, salt shakers were not placed on the tables during mealtimes. Only 14% the participants perceived their personal salt intake to be a little. No participants were aware of the recommended daily salt intake limit or the relationship between salt and sodium. Only five out of the 19 participants had previously received information on dietary salt reduction from sources such as healthcare professionals and the media.

CONCLUSION

The results from the first phase of this study highlighted gaps in the participants' knowledge, attitudes and practices towards dietary salt reduction. The aim of the second phase of the research is to design and implement a context specific and culturally appropriate educational intervention on dietary salt reduction.

Leveraging ongoing research to evaluate the health impacts of South Africa's salt reduction strategy: a prospective nested cohort within the WHO-SAGE multicountry, longitudinal study

INTRODUCTION

Attempting to curb the rising epidemic of hypertension, South Africa implemented legislation in June 2016 mandating maximum sodium levels in a range of manufactured foods that contribute significantly to population salt intake. This natural experiment, comparing two African countries with and without salt legislation, will provide timely information on the impact of legislative approaches addressing the food supply to improve blood pressure in African populations. This article outlines the design of this ongoing prospective nested cohort study.

METHODS AND ANALYSIS

Baseline sodium intake was assessed in a nested cohort of the WHO Study on global AGEing and adult health (WHO-SAGE) wave 2 (2014-2015), a multinational longitudinal study on the health and well-being of adults and the ageing process. The South African cohort consisted of randomly selected households (n=4030) across the country. Spot and 24-hour urine samples are collected in a random subsample (n=1200) and sodium, potassium, creatinine and iodine analysed. Salt behaviour and sociodemographic data are captured using face-to-face interviews, alongside blood pressure and anthropometric measures. Ghana, the selected control country with no formal salt policy, provided a nested subsample (n=1200) contributing spot and 24-hour urine samples from the SAGE Ghana cohort (n=5000). Follow-up interviews and urine collection (wave 3) in both countries will take place in 2017 (postlegislation) to assess change in population-level sodium intake and blood pressure.

ETHICS AND DISSEMINATION

SAGE was approved by the WHO Ethics Review Committee (reference number RPC149) with local approval from the North-West University Human Research Ethics Committee and University of the Witwatersrand Human Research Ethics Committee (South Africa), and University of Ghana Medical School Ethics and Protocol Review Committee (Ghana). The results of the study will be published in peer-reviewed international journals, presented at national and international conferences, and summarised as research and policy briefs.

Effectiveness of a Communication for Behavioral Impact (COMBI) Intervention to Reduce Salt Intake in a Vietnamese Province Based on Estimations From Spot Urine Samples

This study evaluated the effectiveness of the Communication for Behavioral Impact (COMBI)-Eat Less Salt intervention conducted in Viet Tri, Vietnam. The behavior change intervention was implemented in four wards and four communes for one year, which included mass media communication, school interventions, community programs, and focus on high-risk groups. Mean sodium excretion was estimated from spot urine samples using different equations. A subsample provided 24-hour urine to validate estimates from spot urine. Information about salt-related knowledge and behaviors was also collected. There were 513 participants at both baseline and follow-up. Mean sodium excretion estimated from spot urines fell significantly from 8.48 g/d at baseline to 8.05 g/d at follow-up (P=.001). All spot equations demonstrated a significant reduction in sodium levels; however, the change was smaller than the measured 24-hour urine. Participants showed improved knowledge and behaviors following the intervention. The COMBI intervention was effective in lowering average population salt intake and improving knowledge and behaviors.

Global, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks, 1990-2015: a systematic analysis for the Global Burden of Disease Study 2015

BACKGROUND

The Global Burden of Diseases, Injuries, and Risk Factors Study 2015 provides an up-to-date synthesis of the evidence for risk factor exposure and the attributable burden of disease. By providing national and subnational assessments spanning the past 25 years, this study can inform debates on the importance of addressing risks in context.

METHODS

We used the comparative risk assessment framework developed for previous iterations of the Global Burden of Disease Study to estimate attributable deaths, disability-adjusted life-years (DALYs), and trends in exposure by age group, sex, year, and geography for 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks from 1990 to 2015. This study included 388 risk-outcome pairs that met World Cancer Research Fund-defined criteria for convincing or probable evidence. We extracted relative risk and exposure estimates from randomised controlled trials, cohorts, pooled cohorts, household surveys, census data, satellite data, and other sources. We used statistical models to pool data, adjust for bias, and incorporate covariates. We developed a metric that allows comparisons of exposure across risk factors-the summary exposure value. Using the counterfactual scenario of theoretical minimum risk level, we estimated the portion of deaths and DALYs that could be attributed to a given risk. We decomposed trends in attributable burden into contributions from population growth, population age structure, risk exposure, and risk-deleted cause-specific DALY rates. We characterised risk exposure in relation to a Socio-demographic Index (SDI).

FINDINGS

Between 1990 and 2015, global exposure to unsafe sanitation, household air pollution, childhood underweight, childhood stunting, and smoking each decreased by more than 25%. Global exposure for several occupational risks, high body-mass index (BMI), and drug use increased by more than 25% over the same period. All risks jointly evaluated in 2015 accounted for 57·8% (95% CI 56·6-58·8) of global deaths and 41·2% (39·8-42·8) of DALYs. In 2015, the ten largest contributors to global DALYs among Level 3 risks were high systolic blood pressure (211·8 million [192·7 million to 231·1 million] global DALYs), smoking (148·6 million [134·2 million to 163·1 million]), high fasting plasma glucose (143·1 million [125·1 million to 163·5 million]), high BMI (120·1 million [83·8 million to 158·4 million]), childhood undernutrition (113·3 million [103·9 million to 123·4 million]), ambient particulate matter (103·1 million [90·8 million to 115·1 million]), high total cholesterol (88·7 million [74·6 million to 105·7 million]), household air pollution (85·6 million [66·7 million to 106·1 million]), alcohol use (85·0 million [77·2 million to 93·0 million]), and diets high in sodium (83·0 million [49·3 million to 127·5 million]). From 1990 to 2015, attributable DALYs declined for micronutrient deficiencies, childhood undernutrition, unsafe sanitation and water, and household air pollution; reductions in risk-deleted DALY rates rather than reductions in exposure drove these declines. Rising exposure contributed to notable increases in attributable DALYs from high BMI, high fasting plasma glucose, occupational carcinogens, and drug use. Environmental risks and childhood undernutrition declined steadily with SDI; low physical activity, high BMI, and high fasting plasma glucose increased with SDI. In 119 countries, metabolic risks, such as high BMI and fasting plasma glucose, contributed the most attributable DALYs in 2015. Regionally, smoking still ranked among the leading five risk factors for attributable DALYs in 109 countries; childhood underweight and unsafe sex remained primary drivers of early death and disability in much of sub-Saharan Africa.

INTERPRETATION

Declines in some key environmental risks have contributed to declines in critical infectious diseases. Some risks appear to be invariant to SDI. Increasing risks, including high BMI, high fasting plasma glucose, drug use, and some occupational exposures, contribute to rising burden from some conditions, but also provide opportunities for intervention. Some highly preventable risks, such as smoking, remain major causes of attributable DALYs, even as exposure is declining. Public policy makers need to pay attention to the risks that are increasingly major contributors to global burden.

FUNDING

Bill & Melinda Gates Foundation.

Population-level interventions in government jurisdictions for dietary sodium reduction

BACKGROUND

Excess dietary sodium consumption is a risk factor for high blood pressure, stroke and cardiovascular disease. Currently, dietary sodium consumption in almost every country is too high. Excess sodium intake is associated with high blood pressure, which is common and costly and accounts for significant burden of disease. A large number of jurisdictions worldwide have implemented population-level dietary sodium reduction initiatives. No systematic review has examined the impact of these initiatives.

OBJECTIVES

• To assess the impact of population-level interventions for dietary sodium reduction in government jurisdictions worldwide.• To assess the differential impact of those initiatives by social and economic indicators.

SEARCH METHODS

We searched the following electronic databases from their start date to 5 January 2015: the Cochrane Central Register of Controlled Trials (CENTRAL); Cochrane Public Health Group Specialised Register; MEDLINE; MEDLINE In Process & Other Non-Indexed Citations; EMBASE; Effective Public Health Practice Project Database; Web of Science; Trials Register of Promoting Health Interventions (TRoPHI) databases; and Latin American Caribbean Health Sciences Literature (LILACS). We also searched grey literature, other national sources and references of included studies.This review was conducted in parallel with a comprehensive review of national sodium reduction efforts under way worldwide (Trieu 2015), through which we gained additional information directly from country contacts.We imposed no restrictions on language or publication status.

SELECTION CRITERIA

We included population-level initiatives (i.e. interventions that target whole populations, in this case, government jurisdictions, worldwide) for dietary sodium reduction, with at least one pre-intervention data point and at least one post-intervention data point of comparable jurisdiction. We included populations of all ages and the following types of study designs: cluster-randomised, controlled pre-post, interrupted time series and uncontrolled pre-post. We contacted study authors at different points in the review to ask for missing information.

DATA COLLECTION AND ANALYSIS

Two review authors extracted data, and two review authors assessed risk of bias for each included initiative.We analysed the impact of initiatives by using estimates of sodium consumption from dietary surveys or urine samples. All estimates were converted to a common metric: salt intake in grams per day. We analysed impact by computing the mean change in salt intake (grams per day) from pre-intervention to post-intervention.

MAIN RESULTS

We reviewed a total of 881 full-text documents. From these, we identified 15 national initiatives, including more than 260,000 people, that met the inclusion criteria. None of the initiatives were provided in lower-middle-income or low-income countries. All initiatives except one used an uncontrolled pre-post study design.Because of high levels of study heterogeneity (I² > 90%), we focused on individual initiatives rather than on pooled results.Ten initiatives provided sufficient data for quantitative analysis of impact (64,798 participants). As required by the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) method, we graded the evidence as very low due to the risk of bias of the included studies, as well as variation in the direction and size of effect across the studies. Five of these showed mean decreases in average daily salt intake per person from pre-intervention to post-intervention, ranging from 1.15 grams/day less (Finland) to 0.35 grams/day less (Ireland). Two initiatives showed mean increase in salt intake from pre-intervention to post-intervention: Canada (1.66) and Switzerland (0.80 grams/day more per person. The remaining initiatives did not show a statistically significant mean change.Seven of the 10 initiatives were multi-component and incorporated intervention activities of a structural nature (e.g. food product reformulation, food procurement policy in specific settings). Of those seven initiatives, four showed a statistically significant mean decrease in salt intake from pre-intervention to post-intervention, ranging from Finland to Ireland (see above), and one showed a statistically significant mean increase in salt intake from pre-intervention to post-intervention (Switzerland; see above).Nine initiatives permitted quantitative analysis of differential impact by sex (men and women separately). For women, three initiatives (China, Finland, France) showed a statistically significant mean decrease, four (Austria, Netherlands, Switzerland, United Kingdom) showed no significant change and two (Canada, United States) showed a statistically significant mean increase in salt intake from pre-intervention to post-intervention. For men, five initiatives (Austria, China, Finland, France, United Kingdom) showed a statistically significant mean decrease, three (Netherlands, Switzerland, United States) showed no significant change and one (Canada) showed a statistically significant mean increase in salt intake from pre-intervention to post-intervention.Information was insufficient to indicate whether a differential change in mean salt intake occurred from pre-intervention to post-intervention by other axes of equity included in the PROGRESS framework (e.g. education, place of residence).We identified no adverse effects of these initiatives.The number of initiatives was insufficient to permit other subgroup analyses, including stratification by intervention type, economic status of country and duration (or start year) of the initiative.Many studies had methodological strengths, including large, nationally representative samples of the population and rigorous measurement of dietary sodium intake. However, all studies were scored as having high risk of bias, reflecting the observational nature of the research and the use of an uncontrolled study design. The quality of evidence for the main outcome was low. We could perform a sensitivity analysis only for impact.

AUTHORS' CONCLUSIONS

Population-level interventions in government jurisdictions for dietary sodium reduction have the potential to result in population-wide reductions in salt intake from pre-intervention to post-intervention, particularly if they are multi-component (more than one intervention activity) and incorporate intervention activities of a structural nature (e.g. food product reformulation), and particularly amongst men. Heterogeneity across studies was significant, reflecting different contexts (population and setting) and initiative characteristics. Implementation of future initiatives should embed more effective means of evaluation to help us better understand the variation in the effects.

The chemical, microbial, sensory and technological effects of intermediate salt levels as a sodium reduction strategy in fresh pork sausages

BACKGROUND

The reduction of sodium in processed meat products is synonymous with the use of salt replacers. Rarely has there been an assessment of the use of intermediate salt levels as a sodium reduction strategy in itself. In this study, 1 and 1.5% salt levels were compared with 0 and 2% controls in fresh pork sausages for effects on chemical, microbial, sensory and technological stability.

RESULTS

Although significant (P < 0.001 to P < 0.01) differences were found between the 0 and 2% controls, no significant differences could be detected between the 2, 1.5 and 1% added NaCl treatments for the following: total bacteria counts on days 3, 6 and 9; TBARS of pork sausages stored at 4 °C on days 6 and 9 and stored at -18 °C on days 90 and 180; taste, texture and overall liking during sensory evaluation; and % cooking loss, % total loss and % refrigeration loss. Consumers were able to differentiate between the 2 and 1% added NaCl treatments in terms of saltiness.

CONCLUSION

This study indicated that salt reduction to intermediate levels can be considered a sodium reduction strategy in itself but that further research with regards to product safety is needed. © 2015 Society of Chemical Industry.

Salt Intakes, Knowledge, and Behavior in Samoa: Monitoring Salt-Consumption Patterns Through the World Health Organization's Surveillance of Noncommunicable Disease Risk Factors (STEPS)

This project measured population salt intake in Samoa by integrating urinary sodium analysis into the World Health Organization's (WHO's) STEPwise approach to surveillance of noncommunicable disease risk factors (STEPS). A subsample of the Samoan Ministry of Health's 2013 STEPS Survey collected 24-hour and spot urine samples and completed questions on salt-related behaviors. Complete urine samples were available for 293 participants. Overall, weighted mean population 24-hour urine excretion of salt was 7.09 g (standard error 0.19) to 7.63 g (standard error 0.27) for men and 6.39 g (standard error 0.14) for women (P=.0014). Salt intake increased with body mass index (P=.0004), and people who added salt at the table had 1.5 g higher salt intakes than those who did not add salt (P=.0422). A total of 70% of the population had urinary excretion values above the 5 g/d cutoff recommended by the WHO. A reduction of 30% (2 g) would reduce average population salt intake to 5 g/d, in line with WHO recommendations. While challenging, integration of salt monitoring into STEPS provides clear logistical and cost benefits and the lessons communicated here can help inform future programs.

US Food Industry Progress During the National Salt Reduction Initiative: 2009-2014

OBJECTIVES

To assess the US packaged food industry's progress from 2009 to 2014, when the National Salt Reduction Initiative had voluntary, category-specific sodium targets with the goal of reducing sodium in packaged and restaurant foods by 25% over 5 years.

METHODS

Using the National Salt Reduction Initiative Packaged Food Database, we assessed target achievement and change in sales-weighted mean sodium density in top-selling products in 61 food categories in 2009 (n = 6336), 2012 (n = 6898), and 2014 (n = 7396).

RESULTS

In 2009, when the targets were established, no categories met National Salt Reduction Initiative 2012 or 2014 targets. By 2014, 26% of categories met 2012 targets and 3% met 2014 targets. From 2009 to 2014, the sales-weighted mean sodium density declined significantly in almost half of all food categories (43%; 26/61 categories). Overall, sales-weighted mean sodium density declined significantly (by 6.8%; P < .001).

CONCLUSIONS

National target setting with monitoring through a partnership of local, state, and national health organizations proved feasible, but industry progress was modest.

PUBLIC HEALTH IMPLICATIONS

The US Food and Drug Administration's proposed voluntary targets will be an important step in achieving more substantial sodium reductions.

Achieving the WHO sodium target: estimation of reductions required in the sodium content of packaged foods and other sources of dietary sodium

BACKGROUND

Excess sodium intake is one of the top 2 dietary risk factors contributing to the global burden of disease. As such, many countries are now developing national sodium reduction strategies, a key component of which is a sodium reduction model that includes sodium targets for packaged foods and other sources of dietary sodium.

OBJECTIVE

We sought to develop a sodium reduction model to determine the reductions required in the sodium content of packaged foods and other dietary sources of sodium to reduce adult population salt intake by ∼30% toward the optimal WHO target of 5 g/d.

DESIGN

Nationally representative household food-purchasing data for New Zealand were linked with branded food composition information to determine the mean contribution of major packaged food categories to total population sodium consumption. Discretionary salt use and the contribution of sodium from fresh foods and foods consumed away from the home were estimated with the use of national nutrition survey data. Reductions required in the sodium content of packaged foods and other dietary sources of sodium to achieve a 30% reduction in dietary sodium intakes were estimated.

RESULTS

A 36% reduction (1.6 g salt or 628 mg Na) in the sodium content of packaged foods in conjunction with a 40% reduction in discretionary salt use and the sodium content of foods consumed away from the home would reduce total population salt intake in New Zealand by 35% (from 8.4 to 5.5 g/d) and thus meet the WHO 2025 30% relative reduction target. Key reductions required include a decrease of 21% in the sodium content of white bread, 27% for hard cheese, 42% for sausages, and 54% for ready-to-eat breakfast cereals.

CONCLUSIONS

Achieving the WHO sodium target in New Zealand will take considerable efforts by both food manufacturers and consumers and will likely require a national government-led sodium reduction strategy.

State-level and community-level salt reduction initiatives: a systematic review of global programmes and their impact

BACKGROUND

High-salt diets are linked to elevated blood pressure, a major risk factor for cardiovascular diseases, particularly stroke. State and community salt reduction strategies may complement nationally led initiatives and contribute to achieving global salt reduction targets. We aim to systematically review such interventions and document reported impact where programmes have been evaluated.

METHODS

Electronic databases were searched up to June 2015 using terms 'salt' or 'sodium' and 'state' and 'community' in combination with 'campaign', 'initiative', 'project', 'strategy', 'intervention' or 'programme'. Data from evaluated and unevaluated interventions were included. Studies were analysed in relation to intervention components and outcome measures and appraised for quality using a Cochrane Risk-of-Bias Tool.

RESULTS

39 state and community programmes were identified. Settings varied from whole communities (n=23), state-owned buildings (n=5), schools (n=7), workplaces (n=3) and correctional facilities (n=1). Strategies included nutrition education programmes, public education campaigns, changes to the food environment, other 'novel' approaches and multifaceted approaches. Of the 28 studies that evaluated intervention effectiveness, significant reductions were observed in terms of salt intake from dietary assessment (n=7), urinary sodium excretion (n=8), blood pressure (n=11) and sodium in foods (n=9). Six studies reported positive changes in consumer knowledge, attitudes and behaviours. All but two studies had some methodological limitations.

CONCLUSIONS

State and community salt reduction programmes may be effective in a range of settings but more robust evaluation methods are needed. Scaling up these efforts in coordination with national initiatives could provide the most effective and sustainable approach to reducing population salt intake.

Salt Reduction Interventions in Sub-Saharan Africa: A Systematic Review

BACKGROUND

Salt intake is associated with hypertension, the leading risk factor for cardiovascular disease. To promote population-level salt reduction, the World Health Organization recommends intervention around three core pillars: Reformulation of processed foods, consumer awareness, and environmental changes to increase availability and affordability of healthy food. This review investigates salt reduction interventions implemented and evaluated in sub-Saharan Africa (SSA).

METHODS

MEDLINE and google scholar electronic databases were searched for articles meeting inclusion criteria. Studies that reported evaluation results of a salt intervention in SSA were identified. Titles and abstracts were screened, and articles selected for full-text review. Quality of included articles was assessed, and a narrative synthesis of the findings undertaken. PROSPERO registration number CRD42015019055.

RESULTS

Seven studies representing four countries-South Africa, Nigeria, Ghana, and Tanzania-were included. Two examined product reformulation, one in hypertensive patients and the other in normotensive volunteers. Four examined consumer awareness interventions, including individualised counselling and advisory health sessions delivered to whole villages. One study used an environmental approach by offering discounts on healthy food purchases. All the interventions resulted in at least one significantly improved outcome measure including reduction in systolic blood pressure (BP), 24 hour urinary sodium excretion, or mean arterial BP.

CONCLUSIONS

More high quality studies on salt reduction interventions in the region are needed, particularly focused on consumer awareness and education in urban populations given the context of rapid urbanisation; and essentially, targeting product reformulation and environmental change, for greater promise for propagation across a vast, diverse continent.

Dietary sodium and iodine in remote Indigenous Australian communities: will salt-reduction strategies increase risk of iodine deficiency? A cross-sectional analysis and simulation study

Background

Excess salt intake is a global issue. Effective salt-reduction strategies are needed, however, as salt is a vehicle for iodine fortification, these strategies may also reduce iodine intake. This study examines the case of the remote Indigenous Australian population; we employed an innovative, objective method to assess sodium and iodine intakes against requirements and modelled the potential effects of salt-reduction strategies on estimated sodium and iodine intakes.

Design

Store-sales data were collected from 20 remote Indigenous community stores in 2012–14 representing the main source of food for 2 years for ~8300 individuals. Estimated average sodium and iodine intakes were compared against recommendations (nutrient reference values weighted to age and gender distribution). Linear programming was employed to simulate potential effects of salt-reduction strategies on estimated sodium and iodine intakes.

Results

Estimated average sodium intake was 2770 (range within communities 2410–3450) mg/day, far exceeding the population-weighted upper limit (2060 mg/day). Discretionary (added) salt, bread and processed meat were the biggest contributors providing 46 % of all sodium. Estimated average iodine intake was within recommendations at 206 (186–246) μg/day. The following scenarios enabled modelling of estimated average salt intake to within recommendations: 1) 67 % reduction in sodium content of bread and discretionary salt intake, 2) 38 % reduction in sodium content of all processed foods, 3) 30 % reduction in sodium content of all processed foods and discretionary salt intake. In all scenarios, simulated average iodine intakes remained within recommendations.

Conclusions

Salt intakes of the remote Indigenous Australian population are far above recommendations, likely contributing to the high prevalence of hypertension and cardiovascular mortality experienced by this population. Salt-reduction strategies could considerably reduce salt intake in this population without increasing risk of iodine deficiency at the population-level. These data add to the global evidence informing salt-reduction strategies and the evidence that these strategies can be synergistically implemented with iodine deficiency elimination programmes.

Trial registration

Australian New Zealand Clinical Trials Registry: ACTRN12613000694718.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-015-2686-1) contains supplementary material, which is available to authorized users.

Global, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks in 188 countries, 1990-2013: a systematic analysis for the Global Burden of Disease Study 2013

BACKGROUND

The Global Burden of Disease, Injuries, and Risk Factor study 2013 (GBD 2013) is the first of a series of annual updates of the GBD. Risk factor quantification, particularly of modifiable risk factors, can help to identify emerging threats to population health and opportunities for prevention. The GBD 2013 provides a timely opportunity to update the comparative risk assessment with new data for exposure, relative risks, and evidence on the appropriate counterfactual risk distribution.

METHODS

Attributable deaths, years of life lost, years lived with disability, and disability-adjusted life-years (DALYs) have been estimated for 79 risks or clusters of risks using the GBD 2010 methods. Risk-outcome pairs meeting explicit evidence criteria were assessed for 188 countries for the period 1990-2013 by age and sex using three inputs: risk exposure, relative risks, and the theoretical minimum risk exposure level (TMREL). Risks are organised into a hierarchy with blocks of behavioural, environmental and occupational, and metabolic risks at the first level of the hierarchy. The next level in the hierarchy includes nine clusters of related risks and two individual risks, with more detail provided at levels 3 and 4 of the hierarchy. Compared with GBD 2010, six new risk factors have been added: handwashing practices, occupational exposure to trichloroethylene, childhood wasting, childhood stunting, unsafe sex, and low glomerular filtration rate. For most risks, data for exposure were synthesised with a Bayesian meta-regression method, DisMod-MR 2.0, or spatial-temporal Gaussian process regression. Relative risks were based on meta-regressions of published cohort and intervention studies. Attributable burden for clusters of risks and all risks combined took into account evidence on the mediation of some risks such as high body-mass index (BMI) through other risks such as high systolic blood pressure and high cholesterol.

FINDINGS

All risks combined account for 57·2% (95% uncertainty interval [UI] 55·8-58·5) of deaths and 41·6% (40·1-43·0) of DALYs. Risks quantified account for 87·9% (86·5-89·3) of cardiovascular disease DALYs, ranging to a low of 0% for neonatal disorders and neglected tropical diseases and malaria. In terms of global DALYs in 2013, six risks or clusters of risks each caused more than 5% of DALYs: dietary risks accounting for 11·3 million deaths and 241·4 million DALYs, high systolic blood pressure for 10·4 million deaths and 208·1 million DALYs, child and maternal malnutrition for 1·7 million deaths and 176·9 million DALYs, tobacco smoke for 6·1 million deaths and 143·5 million DALYs, air pollution for 5·5 million deaths and 141·5 million DALYs, and high BMI for 4·4 million deaths and 134·0 million DALYs. Risk factor patterns vary across regions and countries and with time. In sub-Saharan Africa, the leading risk factors are child and maternal malnutrition, unsafe sex, and unsafe water, sanitation, and handwashing. In women, in nearly all countries in the Americas, north Africa, and the Middle East, and in many other high-income countries, high BMI is the leading risk factor, with high systolic blood pressure as the leading risk in most of Central and Eastern Europe and south and east Asia. For men, high systolic blood pressure or tobacco use are the leading risks in nearly all high-income countries, in north Africa and the Middle East, Europe, and Asia. For men and women, unsafe sex is the leading risk in a corridor from Kenya to South Africa.

INTERPRETATION

Behavioural, environmental and occupational, and metabolic risks can explain half of global mortality and more than one-third of global DALYs providing many opportunities for prevention. Of the larger risks, the attributable burden of high BMI has increased in the past 23 years. In view of the prominence of behavioural risk factors, behavioural and social science research on interventions for these risks should be strengthened. Many prevention and primary care policy options are available now to act on key risks.

FUNDING

Bill & Melinda Gates Foundation.