Implementing effective salt reduction programs and policies in low- and middle-income countries: learning from retrospective policy analysis in Argentina, Mongolia, South Africa and Vietnam.

OBJECTIVE: To understand the factors influencing the implementation of salt reduction interventions in low- and middle-income countries (LMIC). DESIGN: Retrospective policy analysis based on desk reviews of existing reports and semi-structured stakeholder interviews in four countries, using Walt and Gilson's 'Health Policy Triangle' to assess the role of context, content, process and actors on the implementation of salt policy. SETTING: Argentina, Mongolia, South Africa and Vietnam. PARTICIPANTS: Representatives from government, non-government, health, research and food industry organisations with the potential to influence salt reduction programmes. RESULTS: Global targets and regional consultations were viewed as important drivers of salt reduction interventions in Mongolia and Vietnam in contrast to local research and advocacy, and support from international experts, in Argentina and South Africa. All countries had population-level targets and written strategies with multiple interventions to reduce salt consumption. Engaging industry to reduce salt in foods was a priority in all countries: Mongolia and Vietnam were establishing voluntary programs, while Argentina and South Africa opted for legislation on salt levels in foods. Ministries of Health, the WHO and researchers were identified as critical players in all countries. Lack of funding and technical capacity/support, absence of reliable local data and changes in leadership were identified as barriers to effective implementation. No country had a comprehensive approach to surveillance or regulation for labelling, and mixed views were expressed about the potential benefits of low sodium salts. CONCLUSIONS: Effective scale-up of salt reduction programs in LMIC requires: (1) reliable local data about the main sources of salt; (2) collaborative multi-sectoral implementation; (3) stronger government leadership and regulatory processes and (4) adequate resources for implementation and monitoring.

Mean population salt intake estimated from 24-h urine samples and spot urine samples: a systematic review and meta-analysis.

BACKGROUND: Estimating equations based on spot urine samples have been identified as a possible alternative approach to 24-h urine collections for determining mean population salt intake. This review compares estimates of mean population salt intake based upon spot and 24-h urine samples. METHODS: We systematically searched for all studies that reported estimates of daily salt intake based upon both spot and 24-h urine samples for the same population. The associations between the two were quantified and compared overall and in subsets of studies. RESULTS: A total of 538 records were identified, 108 were assessed as full text and 29 were included. The included studies involved 10,414 participants from 34 countries and made 71 comparisons available for the primary analysis. Overall average population salt intake estimated from 24-h urine samples was 9.3 g/day compared with 9.0 g/day estimated from the spot urine samples. Estimates based upon spot urine samples had excellent sensitivity (97%) and specificity (100%) at classifying mean population salt intake as above or below the World Health Organization maximum target of 5 g/day. Compared with the 24-h samples, estimates based upon spot urine overestimated intake at lower levels of consumption and underestimated intake at higher levels of consumption. CONCLUSIONS: Estimates of mean population salt intake based upon spot urine samples can provide countries with a good indication of mean population salt intake and whether action on salt consumption is required.

Reliable Quantification of the Potential for Equations Based on Spot Urine Samples to Estimate Population Salt Intake: Protocol for a Systematic Review and Meta-Analysis.

BACKGROUND: Methods based on spot urine samples (a single sample at one time-point) have been identified as a possible alternative approach to 24-hour urine samples for determining mean population salt intake. OBJECTIVE: The aim of this study is to identify a reliable method for estimating mean population salt intake from spot urine samples. This will be done by comparing the performance of existing equations against one other and against estimates derived from 24-hour urine samples. The effects of factors such as ethnicity, sex, age, body mass index, antihypertensive drug use, health status, and timing of spot urine collection will be explored. The capacity of spot urine samples to measure change in salt intake over time will also be determined. Finally, we aim to develop a novel equation (or equations) that performs better than existing equations to estimate mean population salt intake. METHODS: A systematic review and meta-analysis of individual participant data will be conducted. A search has been conducted to identify human studies that report salt (or sodium) excretion based upon 24-hour urine samples and spot urine samples. There were no restrictions on language, study sample size, or characteristics of the study population. MEDLINE via OvidSP (1946-present), Premedline via OvidSP, EMBASE, Global Health via OvidSP (1910-present), and the Cochrane Library were searched, and two reviewers identified eligible studies. The authors of these studies will be invited to contribute data according to a standard format. Individual participant records will be compiled and a series of analyses will be completed to: (1) compare existing equations for estimating 24-hour salt intake from spot urine samples with 24-hour urine samples, and assess the degree of bias according to key demographic and clinical characteristics; (2) assess the reliability of using spot urine samples to measure population changes in salt intake overtime; and (3) develop a novel equation that performs better than existing equations to estimate mean population salt intake. RESULTS: The search strategy identified 538 records; 100 records were obtained for review in full text and 73 have been confirmed as eligible. In addition, 68 abstracts were identified, some of which may contain data eligible for inclusion. Individual participant data will be requested from the authors of eligible studies. CONCLUSIONS: Many equations for estimating salt intake from spot urine samples have been developed and validated, although most have been studied in very specific settings. This meta-analysis of individual participant data will enable a much broader understanding of the capacity for spot urine samples to estimate population salt intake.

Developing a national salt reduction strategy for Mongolia.

BACKGROUND: The increase in prevalence of risk factors such as hypertension has contributed to an incremental rise in non-communicable diseases (NCDs) in Mongolia over recent decades, such that they now account for 80% of all deaths in the country. Salt reduction is one of the most cost-effective interventions to reduce the burden of NCDs. METHODS: In 2011, the Ministry of Health (MOH) instigated the development of a national salt reduction strategy for Mongolia. As part of a 2-week national consultation and training program on salt reduction, it established an inter-sectoral working party and organized a series of bilateral meetings and visits to factories. Actions arising included a baseline survey of population salt consumption patterns and the implementation of a series of pilot salt reduction initiatives. RESULTS: The results of the baseline assessment revealed that average daily intake of salt, based on 24 hour urine samples from a representative national sample (n=1,027), was 11.06±5.99 g in 2011, more than double the World Health Organization (WHO) five grams recommendation. Moreover, while most participants knew that salt was bad for health, few were taking efforts to reduce intake, and many were consuming highly salty meals and tea; salt in tea alone was estimated to contribute 30% of daily salt intake. A pilot Pinch Salt intervention to reduce salt consumption of factory workers was undertaken in Ulaanbaatar (UB) city between 2012 and 2013, and was associated with a reduction of 2.8 g of salt intake. Ongoing food industry initiatives have led to significant reductions in salt levels in bread, and companies producing processed meat have indicated a willingness to reduce salt. Relevant stakeholders have also supported the campaign by participating in annual World Salt Awareness Week events. The activities to date have demonstrated the potential for action and there is now a need scale these up to a national level to ensure that Mongolia is in a strong position to achieve a 30% reduction in population salt intake by 2025. The main goal of the Mongolian national salt reduction strategy is to create a social, economic and legal environment that supports salt reduction, including by influencing food supply, increasing partnerships between government and relevant stakeholders, and creating an enabling environment to support improved consumer choices. The strategy will be implemented from 2015 to 2025, with an interim review of progress in 2020. CONCLUSIONS: Given that Mongolia has one of the highest rates of stroke in the world, which is strongly associated with population-wide blood pressure (BP) levels, the addition of a population-based stroke surveillance program would provide a reliable direct assessment of the impact of these salt reduction initiatives on the health of the Mongolian people. The results from this research would likely be widely generalizable to other populations experiencing similar lifestyle transitional changes.