Cost-effectiveness analysis of population salt reduction interventions to prevent cardiovascular disease in Cameroon: mathematical modelling study

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.

Estimated Impact of Achieving the Australian National Sodium Reduction Targets on Blood Pressure, Chronic Kidney Disease Burden and Healthcare Costs: A Modelling Study

Excess sodium intake raises blood pressure which increases the risk of chronic kidney disease (CKD). We aimed to estimate the impact of reduced sodium intake on future CKD burden in Australia. A multi-cohort proportional multistate lifetable model was developed to estimate the potential impact on CKD burden and health expenditure if the Australian Suggested Dietary Target (SDT) and the National Preventive Health Strategy 2021-2030 (NPHS) sodium target were achieved. Outcomes were projected to 2030 and over the lifetime of adults alive in 2019. Achieving the SDT and NPHS targets could lower population mean systolic blood pressure by 2.1 mmHg and 1.7 mmHg, respectively. Compared to normal routines, attaining the SDT and NPHS target by 2030 could prevent 59,220 (95% UI, 53,140-65,500) and 49,890 (44,377-55,569) incident CKD events, respectively, while postponing 568 (479-652) and 511 (426-590) CKD deaths, respectively. Over the lifetime, this generated 199,488 health-adjusted life years (HALYs) and AUD 644 million in CKD healthcare savings for the SDT and 170,425 HALYs and AUD 514 million for the NPHS. CKD due to hypertension and CKD due to other/unspecified causes were the principal contributors to the HALY gains. Lowering sodium consumption in Australia could deliver substantial CKD health and economic benefits.

Avoidable burden of stomach cancer and potential gains in healthy life years from gradual reductions in salt consumption in Vietnam, 2019-2030: a modelling study

OBJECTIVE

Excess salt consumption is causally linked with stomach cancer, and salt intake among adults in Vietnam is about twice the recommended levels. The aim of this study was to quantify the future burden of stomach cancer that could be avoided from population-wide salt reduction in Vietnam.

DESIGN

A dynamic simulation model was developed to quantify the impacts of achieving the 2018 National Vietnam Health Program (8 g/d by 2025 and 7 g/d by 2030) and the WHO (5 g/d) salt reduction policy targets. Data on salt consumption were obtained from the Vietnam 2015 WHO STEPS survey. Health outcomes were estimated over 6-year (2019-2025), 11-year (2019-2030) and lifetime horizons. We conducted one-way and probabilistic sensitivity analyses.

SETTING

Vietnam.

PARTICIPANTS

All adults aged ≥ 25 years (61 million people, 48·4 % men) alive in 2019.

RESULTS

Achieving the 2025 and 2030 national salt targets could result in 3400 and 7200 fewer incident cases of stomach cancer, respectively, and avert 1900 and 4800 stomach cancer deaths, respectively. Achieving the WHO target by 2030 could prevent 8400 incident cases and 5900 deaths from stomach cancer. Over the lifespan, this translated to 344 660 (8 g/d), 411 060 (7 g/d) and 493 633 (5 g/d) health-adjusted life years gained, respectively.

CONCLUSIONS

A sizeable burden of stomach cancer could be avoided, with gains in healthy life years if national and WHO salt targets were attained. Our findings provide impetus for policy makers in Vietnam and Asia to intensify salt reduction strategies to combat stomach cancer and mitigate pressure on the health systems.

Cost-effectiveness of a Household Salt Substitution Intervention: Findings From 20,995 Participants of the Salt Substitute and Stroke Study (SSaSS)

Background:: The Salt Substitute and Stroke Study (SSaSS) ─ a five-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 prior 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 healthcare system and consumers. The primary health outcome assessed was stroke and we also quantified effects on quality-adjusted life years (QALYs). Healthcare costs were identified from participant health insurance records and the literature. All costs (Chinese Yuan - CNY ¥) 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% confidence interval 0.77 to 0.96; p=0.006) and the salt substitute group had on average 0.054 more QALYs per person. The average costs (CNY ¥1,538 for the intervention group and CNY ¥1,649 for the control group) were lower in the salt substitute group (CNY ¥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 greater than 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 amongst the SSaSS participants.

Sodium and Health: Old Myths and a Controversy Based on Denial

Purpose of Review

The scientific consensus on which global health organizations base public health policies is that high sodium intake increases blood pressure (BP) in a linear fashion contributing to cardiovascular disease (CVD). A moderate reduction in sodium intake to 2000 mg per day helps ensure that BP remains at a healthy level to reduce the burden of CVD.

Recent Findings

Yet, since as long ago as 1988, and more recently in eight articles published in the European Heart Journal in 2020 and 2021, some researchers have propagated a myth that reducing sodium does not consistently reduce CVD but rather that lower sodium might increase the risk of CVD. These claims are not well-founded and support some food and beverage industry’s vested interests in the use of excessive amounts of salt to preserve food, enhance taste, and increase thirst. Nevertheless, some researchers, often with funding from the food industry, continue to publish such claims without addressing the numerous objections. This article analyzes the eight articles as a case study, summarizes misleading claims, their objections, and it offers possible reasons for such claims.

Summary

Our study calls upon journal editors to ensure that unfounded claims about sodium intake be rigorously challenged by independent reviewers before publication; to avoid editorial writers who have been co-authors with the subject paper’s authors; to require statements of conflict of interest; and to ensure that their pages are used only by those who seek to advance knowledge by engaging in the scientific method and its collegial pursuit. The public interest in the prevention and treatment of disease requires no less.

Dietary Salt Reduction, Prevalence of Hypertension and Avoidable Burden of Stroke in Vietnam: Modelling the Health and Economic Impacts

Dietary salt reduction has been recommended as a cost-effective population-wide strategy to prevent cardiovascular disease. The health and economic impact of salt consumption on the future burden of stroke in Vietnam is not known.

Objective: To estimate the avoidable incidence of and deaths from stroke, as well as the healthy life years and healthcare costs that could be gained from reducing salt consumption in Vietnam.

Methods: This was a macrosimulation health and economic impact assessment study. Data on blood pressure, salt consumption and stroke epidemiology were obtained from the Vietnam 2015 STEPS survey and the Global Burden of Disease study. A proportional multi-cohort multistate lifetable Markov model was used to estimate the impact of achieving the Vietnam national salt targets of 8 g/day by 2025 and 7 g/day by 2030, and to the 5 g/day WHO recommendation by 2030. Probabilistic sensitivity analysis was conducted to quantify the uncertainty in our projections.

Results: If the 8 g/day, 7 g/day, and 5 g/day targets were achieved, the prevalence of hypertension could reduce by 1.2% (95% uncertainty interval [UI]: 0.5 to 2.3), 2.0% (95% UI: 0.8 to 3.6), and 3.5% (95% UI: 1.5 to 6.3), respectively. This would translate, respectively, to over 80,000, 180,000, and 257,000 incident strokes and over 18,000, 55,000, and 73,000 stroke deaths averted. By 2025, over 56,554 stroke-related health-adjusted life years (HALYs) could be gained while saving over US$ 42.6 million in stroke healthcare costs. By 2030, about 206,030 HALYs (for 7 g/day target) and 262,170 HALYs (for 5 g/day target) could be gained while saving over US$ 88.1 million and US$ 122.3 million in stroke healthcare costs respectively.

Conclusion: Achieving the national salt reduction targets could result in substantial population health and economic benefits. Estimated gains were larger if the WHO salt targets were attained and if changes can be sustained over the longer term. Future work should consider the equity impacts of specific salt reduction programs.