Effect of Salt Substitution on Cardiovascular Events and Death.

BACKGROUND: Salt substitutes with reduced sodium levels and increased potassium levels have been shown to lower blood pressure, but their effects on cardiovascular and safety outcomes are uncertain. METHODS: We conducted an open-label, cluster-randomized trial involving persons from 600 villages in rural China. The participants had a history of stroke or were 60 years of age or older and had high blood pressure. The villages were randomly assigned in a 1:1 ratio to the intervention group, in which the participants used a salt substitute (75% sodium chloride and 25% potassium chloride by mass), or to the control group, in which the participants continued to use regular salt (100% sodium chloride). The primary outcome was stroke, the secondary outcomes were major adverse cardiovascular events and death from any cause, and the safety outcome was clinical hyperkalemia. RESULTS: A total of 20,995 persons were enrolled in the trial. The mean age of the participants was 65.4 years, and 49.5% were female, 72.6% had a history of stroke, and 88.4% a history of hypertension. The mean duration of follow-up was 4.74 years. The rate of stroke was lower with the salt substitute than with regular salt (29.14 events vs. 33.65 events per 1000 person-years; rate ratio, 0.86; 95% confidence interval [CI], 0.77 to 0.96; P = 0.006), as were the rates of major cardiovascular events (49.09 events vs. 56.29 events per 1000 person-years; rate ratio, 0.87; 95% CI, 0.80 to 0.94; P<0.001) and death (39.28 events vs. 44.61 events per 1000 person-years; rate ratio, 0.88; 95% CI, 0.82 to 0.95; P<0.001). The rate of serious adverse events attributed to hyperkalemia was not significantly higher with the salt substitute than with regular salt (3.35 events vs. 3.30 events per 1000 person-years; rate ratio, 1.04; 95% CI, 0.80 to 1.37; P = 0.76). CONCLUSIONS: Among persons who had a history of stroke or were 60 years of age or older and had high blood pressure, the rates of stroke, major cardiovascular events, and death from any cause were lower with the salt substitute than with regular salt. (Funded by the National Health and Medical Research Council of Australia; SSaSS ClinicalTrials.gov number, NCT02092090.).

The potential for current sodium and potassium production to support a global switch to the use of potassium-enriched salt: a desktop research study.

OBJECTIVE: Switching regular salt (sodium chloride) to salt enriched with potassium chloride (25 % potassium chloride, 75 % sodium chloride) has been shown to reduce blood pressure and the risk of cardiovascular diseases. We sought to define the potential for the current production of sodium chloride and potassium chloride to support a global switch to the use of potassium-enriched salt. DESIGN: We summarised data from geological surveys, government reports and trade organisations describing the global production and supply of sodium chloride and potash (the primary source of potassium chloride) and compared this to potential requirements for potassium-enriched salt. SETTING: Global. PARTICIPANTS: Not applicable. RESULTS: Approximately 280 million tonnes of sodium chloride were produced in 2020 with China and the USA the main producers. Global production of potash from which potassium chloride is extracted was about forty-four million tonnes with Canada, Belarus, Russia and China providing 77 % of the world's supply. There were forty-eight countries in which potassium-enriched salt is currently marketed with seventy-nine different brands identified. Allowing for loss of salt between manufacture and consumption, a full global switch from regular salt to potassium-enriched salt would require about 9·7 million tonnes of sodium chloride to be replaced with 9·7 million tonnes of potassium chloride annually. CONCLUSIONS: Significant upscaling of the production of potassium chloride and the capacity of companies able to manufacture potassium-enriched salt, as well as a robust business case for the switch to potassium chloride, would be required.

Safety assessment for nail cosmetics: Framework for the estimation of systemic exposure through the nail plate.

All cosmetics products, including nail care products, must be evaluated for their safety. The assessment of systemic exposure is a key component of the safety assessment. However, data on the exposure, especially via ungual route (nail plate) are limited. Based on the physicochemical properties of human nails and permeability data of topical onychomycosis drugs, the nail plate is considered a good barrier to chemicals. We examine factors impacting penetration of nail care ingredients through the nail plate, including properties of the nails of the ingredients and formulations. The molecular weight, vapor pressure, logP, water solubility, and keratin binding, as well as formulations properties e.g., polymerization of acrylate monomers are considered important factors affecting penetration. To estimate systemic exposure of nail care ingredients through the nail plate, a standardized framework is applied that quantifies the impacts of these properties on penetration with an adjustment factor for each of these influencing properties. All the adjustment factors are then consolidated to derive an integrated adjustment factor which can be used for calculation of the systemic exposure dose for the ingredient. Several case studies are presented to reflect how this framework can be used in the exposure assessment for nail cosmetic products.

Cost-Effectiveness of a Household Salt Substitution Intervention: Findings From 20 995 Participants of the Salt Substitute and Stroke Study.

BACKGROUND: SSaSS (Salt Substitute and Stroke Study), a 5-year cluster randomized controlled trial, demonstrated that replacing regular salt with a reduced-sodium, added-potassium salt substitute reduced the risks of stroke, major adverse cardiovascular events, and premature death among individuals with previous stroke or uncontrolled high blood pressure living in rural China. This study assessed the cost-effectiveness profile of the intervention. METHODS: A within-trial economic evaluation of SSaSS was conducted from the perspective of the health care system and consumers. The primary health outcome assessed was stroke. We also quantified the effect on quality-adjusted life-years (QALYs). Health care costs were identified from participant health insurance records and the literature. All costs (in Chinese yuan [¥]) and QALYs were discounted at 5% per annum. Incremental costs, stroke events averted, and QALYs gained were estimated using bivariate multilevel models. RESULTS: Mean follow-up of the 20 995 participants was 4.7 years. Over this period, replacing regular salt with salt substitute reduced the risk of stroke by 14% (rate ratio, 0.86 [95% CI, 0.77-0.96]; P=0.006), and the salt substitute group had on average 0.054 more QALYs per person. The average costs (¥1538 for the intervention group and ¥1649 for the control group) were lower in the salt substitute group (¥110 less). The intervention was dominant (better outcomes at lower cost) for prevention of stroke as well as for QALYs gained. Sensitivity analyses showed that these conclusions were robust, except when the price of salt substitute was increased to the median and highest market prices identified in China. The salt substitute intervention had a 95.0% probability of being cost-saving and a >99.9% probability of being cost-effective. CONCLUSIONS: Replacing regular salt with salt substitute was a cost-saving intervention for the prevention of stroke and improvement of quality of life among SSaSS participants.

The value of process evaluation for public health interventions: field-case studies for non-communicable disease prevention and management in five countries.

Complex interventions are needed to effectively tackle non-communicable diseases. However, complex interventions can contain a mix of effective and ineffective actions. Process evaluation (PE) in public health research is of great value as it could clarify the mechanisms and contextual factors associ-ated with variation in the outcomes, better identify effective components, and inform adaptation of the intervention. The aim of this paper is to demonstrate the value of PE through five case studies that span the research cycle. The interven-tions include using digital health, salt reduction strategies, use of fixed dose combinations, and task shifting. Insights of the methods used, and the implications of the PE findings to the project, were discussed. PE of complex interventions can refute or confirm the hypothesized mechanisms of action, thereby enabling intervention refinement, and identifying implementation strategies that can address local contextual needs, so as to improve service delivery and public health outcomes.

Impact of Beijing healthcare reform on the curative care expenditure of outpatients with noncommunicable diseases based on SHA2011 and interrupted time series analysis.

BACKGROUND: To analyse the changes in curative care expenditure (CCE) associated with noncommunicable diseases (NCDs) before and after the Beijing healthcare reform, thus providing a reference for the healthcare system. METHODS: A total of 60 medical institutions were selected using multistage stratified cluster random sampling in Beijing, China. The records of approximately 100 million outpatients with NCDs in 2016-2018 were extracted. System of Health Accounts 2011 (SHA2011) was used to estimate the CCE. The segmented regression model was established to observe both the instant change and the slope change of intervention in interrupted time series analysis (ITSA). The study was conducted from December 2019 to May 2020 in Beijing, China. RESULTS: From SHA2011, we found that the CCE for outpatients with NCDs in Beijing were 58.59, 61.46 and 71.96 billion RMB in 2016, 2017 and 2018, respectively. The CCE continued to rise at all hospital levels, namely, tertiary, secondary, and community-level hospitals. However, the proportion of CCE in tertiary hospitals decreased. From ITSA, we can also conclude that the CCE showed a significant increasing trend change at the three hospital levels after the intervention. The drug proportion showed a significant decreasing trend change in secondary and tertiary hospitals. CONCLUSIONS: Beijing healthcare reform does have an impact on the CCE of NCDs.

Sodium Reduction: How Big Might the Risks and Benefits Be?

Cardiovascular diseases are the leading cause of death worldwide and raised blood pressure is the leading risk for these conditions. Excess sodium intake clearly elevates blood pressure though the association of sodium intake with cardiovascular outcomes has been disputed. Nonetheless, it was estimated that in 2017 excess dietary sodium caused between 1.4 and 5.4 million deaths. Key underlying assumptions for those estimates were that the association between sodium intake and cardiovascular disease is direct and linear, and that a daily consumption level of 2.0 g of sodium minimised risk. Recent data indicating that reported U-shaped associations of sodium with risk are the result of confounding provide strong support for the first assumption. Cardiovascular risks may, however, continue to decline below intake levels of 2.0 g per day. Further, because excess sodium intake appears to drive a progressive rise in blood pressure with age, the magnitude of the disease burden avoidable by sodium reduction may have been under-estimated. Regardless, health benefits will only be achieved if safe, effective and scalable interventions can be defined and none have been identified to date. Salt substitution, which switches regular salt for a reduced-sodium, added-potassium alternative offers a significant opportunity. Falls in blood pressure with salt substitution are comparable to single-drug therapy and salt substitutes are low cost, simple to use, well-tolerated and could be applied community-wide. Data that prove clinical benefits and exclude risks will be required to support widespread use. An ongoing large-scale randomised trial of the effects of salt substitution on stroke, major cardiovascular events and death will complete soon and define the role of salt substitutes in public health.

Interim effects of salt substitution on urinary electrolytes and blood pressure in the China Salt Substitute and Stroke Study (SSaSS).

The Salt Substitute and Stroke Study is an ongoing 5-year large-scale cluster randomized trial investigating the effects of potassium-enriched salt substitute compared to usual salt on the risk of stroke. The study involves 600 villages and 20,996 individuals in rural China. Intermediate risk markers were measured in a random subsample of villages every 12 months over 3 years to track progress against key assumptions underlying study design. Measures of 24-hour urinary sodium, 24-hour urinary potassium, blood pressure and participants' use of salt substitute were recorded, with differences between intervention and control groups estimated using generalized linear mixed models. The primary outcome of annual event rate in the two groups combined was determined by dividing confirmed fatal and non-fatal strokes by total follow-up time in the first 2 years. The mean differences (95% CI) were -0.32 g (-0.68 to 0.05) for 24-hour urinary sodium, +0.77 g (+0.60 to +0.93) for 24-hour urinary potassium, -2.65 mmHg (-4.32 to -0.97) for systolic blood pressure and +0.30 mmHg (-0.72 to +1.32) for diastolic blood pressure. Use of salt substitute was reported by 97.5% in the intervention group versus 4.2% in the control group (P<.0001). The overall estimated annual event rate for fatal and non-fatal stroke was 3.2%. The systolic blood pressure difference and the annual stroke rate were both in line with the statistical assumptions underlying study design. The trial should be well placed to address the primary hypothesis at completion of follow-up.

Inpatient Cost of Stroke in Beijing: A Descriptive Analysis.

BACKGROUND: Stroke has been the leading cause of death in China and contributed almost one-third to stroke deaths worldwide. The rising cost of stroke treatment is of great concern, but has not been thoroughly studied. This study aimed to analyze stroke in-hospital charges by subtypes, age, and sex and investigate potential factors associated with the cost of per stay. METHODS: The research was a retrospective observational study based on patients with a primary diagnosis of stroke from 31 hospitals in Beijing. Characteristics of total treatment cost and cost of per stay were analyzed. The potential influences on hospital charges were explored using a stepwise multiple regression model. RESULTS: A total of 16,111 stroke in-patient admissions were identified among which 8.3% was subarachnoid hemorrhage, 22.4% intracerebral hemorrhage, and 69.1% cerebral infarction. The average length of stay (LoS) was 14.5 (11.9) days. The cost of per stay was USD 4,423.9 (6,684.4) among which the out-of-pocket expenses were USD 1,640.2 (3,118.0). Stroke type, age, medical insurance, treatment results, and hospital level were significantly associated with the cost of stroke (p < 0.001). CONCLUSION: Hospitalization cost of stroke was substantial. These findings provide health policymakers and healthcare professionals with evidence to help guide future spending.

A qualitative evaluation of a simplified cardiovascular management program in Tibet, China.

BACKGROUND: The simplified cardiovascular management (SimCard Study) program was a cluster randomized controlled trial conducted in Tibet, China to evaluate a multifaceted intervention consisting of appropriate medication prescriptions and lifestyle recommendations delivered by village doctors. The intervention was effective in improving the management of cardiovascular diseases in resource-limited settings. The aim of this qualitative study was to examine stakeholder feedback and to inform future research and scaling up. METHOD: A total of 28 face-to-face individual interviews were conducted. The interviews were conducted in 6 out of 14 intervention villages by 2 interviewers who speak the local language. Participants included 18 community members at high risk of CVD, 6 village doctors, 2 local project coordinators, and 2 county officials. Interview guides were used to facilitate the interview covering the focus of perceived usefulness and content of the intervention, fidelity to the intervention, and potential scalability of the intervention. Qualitative interviews were coded using thematic analysis. RESULTS: The average age of the participants was 41 years and 70% were female. Our findings showed that the intervention was delivered according to the protocol and was described as a useful program for CVD management by both high-risk individuals and village doctors. However, lack of knowledge among high-risk individuals, insufficient availability of healthcare providers, inadequate financial incentive, and incomplete infrastructure such as difficulty in transportation and cell phone signal were identified as the main barriers to successful implementation and scale-up. CONCLUSION: The intervention was implemented in line with the protocol and provided substantial benefits for relevant community members and health professionals. However, multiple health system barriers need to be addressed for successful scale-up in rural China. TRIAL REGISTRATION: Unique identifier: NCT01503814 . Registered 11 December 2011.

Sodium and potassium content of 24 h urinary collections: a comparison between field- and laboratory-based analysers.

OBJECTIVE: Measurement of mean population Na and K intakes typically uses laboratory-based assays, which can add significant logistical burden and costs. A valid field-based measurement method would be a significant advance. In the current study, we used 24 h urine samples to compare estimates of Na, K and Na:K ratio based upon assays done using the field-based Horiba twin meter v. laboratory-based methods. DESIGN: The performance of the Horiba twin meter was determined by comparing field-based estimates of mean Na and K against those obtained using laboratory-based methods. The reported 95 % limits of agreement of Bland-Altman plots were calculated based on a regression approach for non-uniform differences. SETTING: The 24 h urine samples were collected as part of an ongoing study being done in rural China. SUBJECTS: One hundred and sixty-six complete 24 h urine samples were qualified for estimating 24 h urinary Na and K excretion. RESULTS: Mean Na and K excretion were estimated as 170·4 and 37·4 mmol/d, respectively, using the meter-based assays; and 193·4 and 43·8 mmol/d, respectively, using the laboratory-based assays. There was excellent relative reliability (intraclass correlation coefficient) for both Na (0·986) and K (0·986). Bland-Altman plots showed moderate-to-good agreement between the two methods. CONCLUSIONS: Na and K intake estimations were moderately underestimated using assays based upon the Horiba twin meter. Compared with standard laboratory-based methods, the portable device was more practical and convenient.

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.

Examining the Use and Application of the WHO Integrated People-Centred Health Services Framework in Research Globally - a Systematic Scoping Review.

Introduction: The World Health Organisation (WHO) accepted the Integrated People-centred Health Services (IPCHS) framework in 2016 as an essential component for achieving universal health coverage in fragmented health systems. We aimed to examine the empirical applications of the WHO IPCHS framework to guide its use in strengthening health-service research. Methods: Academic databases and the IPCHS website were searched for relevant articles published between 2016 and July 2023. Two reviewers independently screened and extracted data on the study design, setting, IPCHS framework components, and facilitators and barriers to implementing the IPCHS strategies. Descriptive and content analyses were conducted. Results: Six studies were identified using the IPCHS framework. Studies have examined a combination of the five IPCHS strategies. All studies reported building strong primary care-based systems and coordinating care for individuals. Continued relationships and trust, co-production of health programmes, diversity of health care team, and technology were major facilitators, while low health literacy, lack of primary setting capacity and healthcare workforce were principal barriers to IPCHS implementation. Conclusion: This scoping review offers an overview of IPCHS strategies employed in healthcare research. Generally, the IPCHS framework remains underutilised in primary research. These results offer guidance for future research to support effective healthcare delivery.

Understanding Gaps in the Hypertension and Diabetes Care Cascade: Systematic Scoping Review.

BACKGROUND: Hypertension and diabetes are global health challenges requiring effective management to mitigate their considerable burden. The successful management of hypertension and diabetes requires the completion of a sequence of stages, which are collectively termed the care cascade. OBJECTIVE: This scoping review aimed to describe the characteristics of studies on the hypertension and diabetes care cascade and identify potential interventions as well as factors that impact each stage of the care cascade. METHODS: The method of this scoping review has been guided by the framework by Arksey and O'Malley. We systematically searched MEDLINE, Embase, and Web of Science using terms pertinent to hypertension, diabetes, and specific stages of the care cascade. Articles published after 2011 were considered, and we included all studies that described the completion of at least one stage of the care cascade of hypertension and diabetes. Study selection was independently performed by 2 paired authors. Descriptive statistics were used to elucidate key patterns and trends. Inductive content analysis was performed to generate themes regarding the barriers and facilitators for improving the care cascade in hypertension and diabetes management. RESULTS: A total of 128 studies were included, with 42.2% (54/128) conducted in high-income countries. Of them, 47 (36.7%) focused on hypertension care, 63 (49.2%) focused on diabetes care, and only 18 (14.1%) reported on the care of both diseases. The majority (96/128, 75.0%) were observational in design. Cascade stages documented in the literature were awareness, screening, diagnosis, linkage to care, treatment, adherence to medication, and control. Most studies focused on the stages of treatment and control, while a relative paucity of studies examined the stages before treatment initiation (76/128, 59.4% vs 52/128, 40.6%). There was a wide spectrum of interventions aimed at enhancing the hypertension and diabetes care cascade. The analysis unveiled a multitude of individual-level and system-level factors influencing the successful completion of cascade sequences in both high-income and low- and middle-income settings. CONCLUSIONS: This review offers a comprehensive understanding of hypertension and diabetes management, emphasizing the pivotal factors that impact each stage of care. Future research should focus on upstream cascade stages and context-specific interventions to optimize patient retention and care outcomes.

The Guidelines for use and promotion of low sodium salt in China.

AIM: Both excessive intake of sodium and inadequate intake of potassium are associated with blood pressure elevation and subsequent increase in the risk of cardiovascular disease, which accounts for the largest number of deaths in China and worldwide. Low sodium salt, a mixture of mainly sodium chloride and potassium chloride, has shown its great potential as a promising population strategy for sodium intake reduction through multiple large-scale, multicenter, randomized controlled trials among populations including patients with cardiovascular disease, individuals with and without hypertension, older and younger adults, and men and women in China and other countries. This Guidelines aims to provide expert recommendations for promotion and use of low sodium salt in China, based on the current available scientific evidence regarding the effectiveness, safety, cost-effectiveness, and acceptability of low sodium salts in various population groups and different application scenarios. The suggestions to key stakeholders are also made. METHODS: A working group, an expert review committee and an advisory committee were established to be responsible for formulating the guidelines' scope and key questions to be addressed, for searching, synthesizing, and evaluating research evidence, proposing and reviewing the recommendations. The consensus on the final recommendations was reached using the GRADE grid method. RESULTS: The working group summarized current available evidence of salt substitution regarding its effectiveness, safety, cost-effectiveness, acceptability, availability, suitability, etc. The Guidelines provided six recommendations advising different populations how to use low sodium salt, four recommendations on the application of low sodium salts in different scenarios, and five suggestions for key stakeholders to promote salt substitution. CONCLUSION: The first evidence-based guidelines on promotion and use of low sodium salts covers all key questions in relevance and would play a critical role in prevention and control of hypertension and cardiovascular disease in China and worldwide.

Effectiveness of Multifaceted Strategies to Increase Influenza Vaccination Uptake: A Cluster Randomized Trial.

Importance: Influenza vaccination rates remain low among primary school students and vary by school in Beijing, China. Theory-informed, multifaceted strategies are needed to improve influenza vaccination uptake. Objective: To evaluate the effectiveness of multifaceted strategies in improving influenza vaccination uptake among primary school students. Design, Setting, and Participants: This cluster randomized trial was conducted from September 2022 to May 2023 across primary schools in Beijing, China. Schools were allocated randomly in a 1:1 ratio to multifaceted strategies or usual practice. Schools were deemed eligible if the vaccination rates in the 2019 to 2020 season fell at or below the district-wide average for primary schools. Eligible participants included students in grades 2 and 3 with no medical contraindications for influenza vaccination. Intervention: The multifaceted strategies intervention involved system-level planning and coordination (eg, developing an implementation blueprint, building social norms, and enhancing supervision), school-level training and educating school implementers (eg, conducting a 1-hour training and developing educational materials), and individual-level educating and reminding students and parents (eg, conducting educational activities and sending 4 reminders about vaccination). Main Outcomes and Measures: The primary outcomes were influenza vaccination uptake at school reported by school clinicians as well as overall vaccine uptake either at school or outside of school as reported by parents at 3 months. Generalized linear mixed models were used for analysis. Results: A total of 20 schools were randomized. One intervention school and 2 control schools did not administer vaccination on school grounds due to COVID-19, resulting in a total of 17 schools (9 intervention and 8 control). There was a total of 1691 students aged 7 to 8 years (890 male [52.6%]; 801 female [47.4%]) including 915 in the intervention group and 776 in the control group. Of all participants, 848 (50.1%) were in grade 2, and 1209 (71.5%) were vaccinated in the 2021 to 2022 season. Participants in the intervention and control groups shared similar characteristics. At follow-up, of the 915 students in the intervention group, 679 (74.5%) received a vaccination at school, and of the 776 students in the control group, 556 (71.7%) received a vaccination at school. The overall vaccination rates were 76.0% (695 of 915 students) for the intervention group and 71.3% (553 of 776 students) for the control group. Compared with the control group, there was significant improvement of vaccination uptake at school (odds ratio, 1.40; 95% CI, 1.06-1.85; P = .02) and overall uptake (odds ratio, 1.49; 95% CI, 1.12-1.99; P = .01) for the intervention group. Conclusions and Relevance: In this study, multifaceted strategies showed modest effectiveness in improving influenza vaccination uptake among primary school students, which provides a basis for the implementation of school-located vaccination programs of other vaccines in China, and in other countries with comparable programs. Trial registration: Chinese Clinical Trial Registry: ChiCTR2200062449.

Secondary Analysis of the Salt Substitute and Stroke Study (SSaSS): Effects of Potassium-Enriched Salt on Cardiac Outcomes.

BACKGROUND: The SSaSS (Salt Substitute and Stroke Study) has shown that use of a potassium-enriched salt lowers the risk of stroke, total cardiovascular events, and premature death. The effects on cause-specific cardiac outcomes are reported here. METHODS: SSaSS was an unblinded, cluster-randomised trial assessing the effects of potassium-enriched salt compared with regular salt among 20 995 Chinese adults with established stroke and older age and uncontrolled hypertension. Post hoc efficacy analyses were performed using an intention-to-treat method and a hierarchical Poisson regression model adjusting for clustering to obtain rate ratios and 95% CIs. We assessed acute coronary syndrome, heart failure, arrhythmia, and sudden death. RESULTS: Over a mean 4.74 years follow-up, there were 695 acute coronary syndrome events, 454 heart failure events, 230 arrhythmia events, and 1133 sudden deaths recorded. The rates of events were lower in potassium-enriched salt group for all outcomes but CIs were wide for most: acute coronary syndrome (6.32 versus 7.65 events per 1000 person-years; rate ratio, 0.80 [95% CI, 0.65-0.99]); heart failure (9.14 versus 11.32 events per 1000 person-years; rate ratio, 0.88 [95% CI, 0.60-1.28]); arrhythmia (4.43 versus 6.20 events per 1000 person-years; rate ratio, 0.59 [95% CI, 0.35-0.98]); and sudden death (11.01 versus 11.76 events per 1000 person-years; rate ratio, 0.94 [95% CI, 0.82-1.07]; all P>0.05 with adjustment for multiple comparisons). CONCLUSIONS: These results suggest that use of potassium-enriched salt is more likely to prevent than cause cardiac disease but the post hoc nature of these analyses precludes definitive conclusions. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02092090.

The contribution of sodium reduction and potassium increase to the blood pressure lowering observed in the Salt Substitute and Stroke Study.

The Salt Substitute and Stroke Study (SSaSS) demonstrated significant reductions in systolic blood pressure (SBP), and the risk of stroke, major cardiovascular events and total mortality with the use of potassium-enriched salt. The contribution of sodium reduction versus potassium increase to these effects is unknown. We identified four different data sources describing the association between sodium reduction, potassium supplementation and change in SBP. We then fitted a series of models to estimate the SBP reductions expected for the differences in sodium and potassium intake in SSaSS, derived from 24-h urine collections. The proportions of the SBP reduction separately attributable to sodium reduction and potassium supplementation were calculated. The observed SBP reduction in SSaSS was -3.3 mmHg with a corresponding mean 15.2 mmol reduction in 24-h sodium excretion and a mean 20.6 mmol increase in 24-h potassium excretion. Assuming 90% of dietary sodium intake and 70% of dietary potassium intake were excreted through urine, the models projected falls in SBP of between -1.67 (95% confidence interval: -4.06 to +0.73) mmHg and -5.33 (95% confidence interval: -8.58 to -2.08) mmHg. The estimated proportional contribution of sodium reduction to the SBP fall ranged between 12 and 39% for the different models fitted. Sensitivity analyses assuming different proportional urinary excretion of dietary sodium and potassium intake showed similar results. In every model, the majority of the SBP lowering effect in SSaSS was estimated to be attributable to the increase in dietary potassium rather than the fall in dietary sodium.

The effect of salt substitution on frequency and severity of headache: results from the SSaSS cluster-randomised controlled trial of 20,995 participants.

BACKGROUND: Headache is one of the most common neurological symptoms. Headache disorders are associated with a high global burden of disease. Prior studies indicate that short-to-medium term sodium reduction reduces headache symptom. This study evaluated the effects of long-term reduced-sodium, added-potassium salt on headache frequency and severity in rural China. METHODS: The Salt substitute and stroke study (SSaSS) was an open-label cluster-randomised trial in rural China designed to evaluate the effect of salt substitution on mortality and cardiovascular events. Participants included adults with a history of prior stroke and those aged ≥60 years with uncontrolled high blood pressure (BP). Villages were randomly assigned in a 1:1 ratio either to intervention with salt substitute (75% sodium chloride and 25% potassium chloride by mass) or to control with continued use of regular salt (100% sodium chloride). In this pre-specified analysis, between-group differences in headache frequency and severity were evaluated. The study was registered with ClinicalTrials.gov (identifier number: NCT02092090). RESULTS: A total of 20,995 participants were included in the trial (mean age 64.3 years, 51% female, mean follow-up 4.7 years). At final follow-up at the end of the study, headache outcome data including frequency and severity of headaches was available for 16,486 (98%) of 16,823 living participants. Overall, 4454/16,486 (27%) individuals reported having headache: 27.4% in the intervention group (2301/8386) vs 26.6% in the control group (2153/8100) (RR 1.04, 95% CI: 0.93, 1.16, p = 0.48). There was no difference in headache severity between intervention and control groups (p = 0.90). CONCLUSION: Long term salt substitution did not reduce the frequency or severity of headaches in this population.

Consumers' Perceptions of the Design of Front-of-Package Warning Labels-A Qualitative Study in China.

The warning label is identified as a simple front-of-package labeling format that assists consumers in making healthier food choices at the point of purchase. The color and/or shape of the design elements of the packaging labels can influence the understanding and purchase intention outcomes. This study aimed to explore the perceptions of consumers regarding differently designed warning labels (WLs) to identify a possibly suitable warning label design in the Chinese context. Using a qualitative approach, we collected data through 12 focus group discussions consisting of 116 participants residing in 6 provinces. Participants were selected by purposive sampling. Data were coded following inductive thematic analysis and summarized into three themes: (1) perceived preference for the appearance of the WLs, (2) perceived benefits of the WLs, and (3) suggestions for promoting the WLs. Participants preferred the black shield label showing a high content of the nutrients of concern (e.g., sodium, added sugar, and saturated fat) in both Chinese and English. Consumers generally agreed that the WLs were easy to understand and offered a simple method for choosing healthier foods. They anticipated that WLs could encourage the food industry to reformulate their products. Our study results will support the design and facilitate the use of WLs in China.