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

Importance: Salt substitution has been reported to be a cost-saving sodium reduction strategy that has not yet been replicated in different contexts. Objective: To estimate the cost-effectiveness of sodium reduction strategies within the DECIDE-Salt trial. Design, Setting, and Participants: The DECIDE-Salt trial cluster randomized in a 1:1:1:1 ratio 48 eldercare facilities in China into 4 groups for evaluation of 2 sodium reduction strategies for 2 years: 1 with both strategies, 2 with either strategy, and 1 with neither strategy. The trial was conducted from September 25, 2017, through October 24, 2020. Interventions: The 2 intervention strategies were replacing regular salt with salt substitute and progressively restricting salt supply to kitchens. Main Outcomes and Measures: The main outcomes included per-participant costs of intervention implementation and medical treatments for hypertension and major adverse cardiovascular events (MACEs) against mean reductions in systolic blood pressure, hypertension prevalence, MACE incidence, and mortality. The incremental cost-utility ratio was then assessed as the additional mean cost per quality-adjusted life-year gained. Analyses were conducted separately for each strategy, comparing groups assigned and not assigned the test strategy. Disease outcomes followed the intention-to-treat principle and adopted different models as appropriate. One-way and probabilistic sensitivity analyses were conducted to explore uncertainty, and data analyses were performed between August 13, 2022, and April 5, 2023. Results: A total of 1612 participants (1230 males [76.3%]) with a mean (SD) age of 71.0 (9.5) years were enrolled. Replacing regular salt with salt substitute reduced mean systolic blood pressure by 7.14 (95% CI, 3.79-10.48) mm Hg, hypertension prevalence by 5.09 (95% CI, 0.37-9.80) percentage points, and cumulative MACEs by 2.27 (95% CI, 0.09-4.45) percentage points. At the end of the 2-year intervention, the mean cost was $25.95 less for the salt substitute group than the regular salt group due to substantial savings in health care costs for MACEs (mean [SD], $72.88 [$9.11] vs $111.18 [$13.90], respectively). Sensitivity analysis showed robust cost savings. By contrast, the salt restriction strategy did not show significant results. If the salt substitution strategy were rolled out to all eldercare facilities in China, 48 101 MACEs and 107 857 hypertension cases were estimated to be averted and $54 982 278 saved in the first 2 years. Conclusions and Relevance: The findings of this cluster randomized clinical trial indicate that salt substitution may be a cost-saving strategy for hypertension control and cardiovascular disease prevention for residents of eldercare facilities in China. The substantial health benefit savings in preventing MACEs and moderate operating costs offer strong evidence to support the Chinese government and other countries in planning or implementing sodium intake reduction and salt substitute campaigns. Trial Registration: ClinicalTrials.gov Identifier: NCT03290716.

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.

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

INTRODUCTION: Cardiovascular diseases (CVDs) are the leading causes of death and disability worldwide. Reducing dietary salt consumption is a potentially cost-effective way to reduce blood pressure and the burden of CVD. To date, economic evidence has focused on sodium reduction in food industry or processed food with blood pressure as the primary outcome. This study protocol describes the planned within-trial economic evaluation of a low-sodium salt substitute intervention designed to reduce the risk of stroke in China. METHODS AND ANALYSES: The economic evaluation will be conducted alongside the Salt Substitute and Stroke Study: a 5-year large scale, cluster randomised controlled trial. The outcomes of interest are quality of life measured using the EuroQol-5-Dimensions and major adverse cardiovascular events. Costs will be estimated from a healthcare system perspective and will be sought from the routinely collected data available within the New Rural Cooperative Medical Scheme. Cost-effectiveness and cost-utility analyses will be conducted, resulting in the incremental cost-effectiveness ratio expressed as cost per cardiovascular event averted and cost per quality-adjusted life year gained, respectively. ETHICS AND DISSEMINATION: The trial received ethics approval from the University of Sydney Ethics Committee (2013/888) and Peking University Institutional Review Board (IRB00001052-13069). Informed consent was obtained from each study participant. Findings of the economic evaluation will be published in a peer-reviewed journal and presented at international conferences. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT02092090).

Multifunctionality assessment of the land use system in rural residential areas: Confronting land use supply with rural sustainability demand.

By applying an integrated framework, we developed a new way to quantify the multifunctionality of rural residential land: analyzing the reciprocal relationships between the structure and function of land use, as well as identifying the demand of rural sustainability for residential land functions. In the assessment of the rural residential land functions from the supply and demand perspectives by establishing an indicators system, the results show that there are five substantial functions of rural residential land, i.e., residential, public service, industrial, commercial and ecological function, and a potential function. Unbalanced development patterns between function supply and demand are clearly observed at multilevel: at the regional level, demand exceeding supply refers to the public service, commercial, and ecological function, especially for ecological function; at the town level, the spatial pattern of the difference is closely linked with topographic features; the inferior and complex topographic condition always is associated with inadequate function supply. Strategies based on the arrangements of rural residential land use structure, including function conversion and function enhancement, have been adopted to balance the supply and demand of land functions. Together, alternative strategies (e.g., industrial allocation, population introduction, and location choices) also need to be recognized by policymakers to achieve rural sustainable development.

Validation and Assessment of Three Methods to Estimate 24-h Urinary Sodium Excretion from Spot Urine Samples in High-Risk Elder Patients of Stroke from the Rural Areas of Shaanxi Province.

Background: 24-h urine collection is regarded as the "gold standard" for monitoring sodium intake at the population level, but ensuring high quality urine samples is difficult to achieve. The Kawasaki, International Study of Sodium, Potassium, and Blood Pressure (INTERSALT) and Tanaka methods have been used to estimate 24-h urinary sodium excretion from spot urine samples in some countries, but few studies have been performed to compare and validate these methods in the Chinese population. Objective: To compare and validate the Kawasaki, INTERSALT and Tanaka formulas in predicting 24-h urinary sodium excretion using spot urine samples in 365 high-risk elder patients of strokefrom the rural areas of Shaanxi province. Methods: Data were collected from a sub-sample of theSalt Substitute and Stroke Study. 365 high-risk elder patients of stroke from the rural areas of Shaanxi province participated and their spot and 24-h urine specimens were collected. The concentrations of sodium, potassium and creatinine in spot and 24-h urine samples wereanalysed. Estimated 24-h sodium excretion was predicted from spot urine concentration using the Kawasaki, INTERSALT, and Tanaka formulas. Pearson correlation coefficients and agreement by Bland-Altman method were computed for estimated and measured 24-h urinary sodium excretion. Results: The average 24-h urinary sodium excretion was 162.0 mmol/day, which representing a salt intake of 9.5 g/day. Three predictive equations had low correlation with the measured 24-h sodium excretion (r = 0.38, p < 0.01; ICC = 0.38, p < 0.01 for the Kawasaki; r = 0.35, p < 0.01; ICC = 0.31, p < 0.01 for the INTERSALT; r = 0.37, p < 0.01; ICC = 0.34, p < 0.01 for the Tanaka). Significant biases between estimated and measured 24-h sodium excretion were observed (all p < 0.01 for three methods). Among the three methods, the Kawasaki method was the least biased compared with the other two methods (mean bias: 31.90, 95% Cl: 23.84, 39.97). Overestimation occurred when the Kawasaki and Tanaka methods were used while the INTERSALT method underestimated 24-h sodium excretion. Conclusion: The Kawasaki, INTERSALT and Tanaka methods for estimation of 24-h urinary sodium excretion from spot urine specimens were inadequate for the assessment of sodium intake at the population level in high-risk elder patients of stroke from the rural areas of Shaanxi province, although the Kawasaki method was the least biased compared with the other two methods.