Low Sodium Salt Prevents Stroke-ScienceDaily

Both increased sodium intake and decreased potassium intake are associated with increased risk of hypertension and cardiovascular disease and premature death.^3,4 Alternative salts that replace some of the normal salt sodium chloride with potassium chloride have been shown to lower blood pressure^Five However, their effects on heart disease, stroke, and death were uncertain. In addition, there was concern that it could cause hyperkalemia in people with chronic kidney disease that could lead to cardiac arrhythmias and sudden death.

The Salt Substitute and Stroke Study (SSaSS) compared the effects of sodium salt substitutes and conventional salts on stroke, cardiovascular events, mortality, and clinical hyperkalemia.⁶ SSaSS was an open cluster randomized trial that enrolled participants between April 2014 and January 2015. Participants were adults with a previous stroke or over 60 years of age and poorly controlled blood pressure.⁷

The test was conducted in 600 villages in rural areas of five provinces in China. Two counties within each state are selected to represent the level of socio-economic development of the province’s local counties. About 35 people were hired from each village, and a total of 20,995 people participated. Participants were cluster-randomized by village at a ratio of 1: 1 to the provision of salt substitutes or continued use of regular salt.

Participants in the intervention village will be given free salt substitutes (about 75% sodium chloride and 25% potassium chloride) instead of regular salt and should be used for all dishes, seasonings and food preservation. Was advised. They were also encouraged to use salt alternatives more sparingly than previously used salt to maximize sodium reduction. Sufficient alternative salt was provided to meet the needs of the entire household (about 20 g per person per day). Control Village participants continued their normal habits.

The average age of participants was 65.4 years, with 49.5% being female. About 72.6% had a history of stroke and 88.4% had a history of hypertension.

During an average follow-up of 4.74 years, more than 3,000 had strokes, more than 4,000 died, and more than 5,000 had major cardiovascular events.The risk of stroke was reduced with alternative salts compared to regular salts (29.14 vs. 33.65 per 1,000 patient years; rate ratio) [RR] 0.86; 95% confidence interval [CI] 0.77-0.96; p = 0.006).

For secondary outcomes, major cardiovascular events (non-fatal stroke, non-fatal acute coronary syndrome, vascular death) were reduced by alternative salts (49.09 vs. 56.29 per 1,000 patient years; RR 0.87; 95% CI 0.80-0.94). P <0.001) Similar to total mortality (39.27 vs. 44.61 per 1,000 patient years; RR 0.88; 95% CI 0.82-0.95; p <0.001).

In terms of safety, there was no increased risk of serious adverse events resulting from clinical hyperkalemia with salt substitutes compared to regular salts (3.35 vs. 3.30 per 1,000 patient years; RR 1.04). 95% CI 0.80-1.37; p = 0.76). No other risks were identified.

Professor Bruce Neal, a senior researcher at the George Global Health Institute in Sydney, Australia, said: And if alternative salts prove to be effective, it can avoid premature deaths of 461,000 people each year in China.⁸ We have now shown that it is effective, and these are benefits only for China. Salt alternatives can be used by billions of people with even greater benefits. “

“The test results are particularly exciting because salt substitution is one of the few practical ways to achieve the changes in salt that people eat. Other salt reduction interventions achieve large and lasting effects. I had a hard time. “

“Importantly, alternative salt is very easy to manufacture and not expensive. A kilo of regular salt that lasts for several months costs about US $ 1.08 in China. The price of one kilo of alternative salt is 1.62. / kg, “he said. “Adding large amounts of salt during cooking and cooking of food is primarily for low-income and disadvantaged people.⁹ This means that alternative salts may reduce health inequality associated with cardiovascular disease. “

Note

¹SSaSS: Salt Substitute and Stroke Studies on the Effects of Salt Substitutes on Cardiovascular Events and Death

²Tian M, et al. Effect of salt substitutes on cardiovascular events and death (SSaSS). N Engl J Med.. 10.1056 / NEJMoa2105675

³Cogswell ME, Mugavero K, Bowman BA, Frieden TR. Dietary Sodium and Cardiovascular Risk-Measurement is Important. N Engl J Med. 2016; 375: 580-586.

^FourAbrut, NJ, Hanson S, Gutierrez H, et al.. Impact of increased potassium intake on cardiovascular risk factors and disease: systematic review and meta-analysis. BMJ. 2013; 346: f1378.

^FiveGreer RC, Markland M, Anderson CAM, et al.. A substitute for potassium-rich salt as a means of lowering blood pressure. High blood pressure. 2020; 75: 266-274.

⁶Neal B, Tian M, Li N, et al.. Salt Substitution and Stroke Study (SSaSS) Rationale, Design, and Baseline Characteristics-Large Cluster Randomized Controlled Trials. This is Heart J. 2017; 188: 109-117.

⁷Uncontrolled blood pressure was defined as systolic blood pressure ≥140 mmHg when taking antihypertensive drugs and systolic blood pressure ≥160 mmHg when not taking antihypertensive drugs.

⁸Marklund M, Singh G, Greer R, et al.. Estimated overall population benefits and risks of sodium decline due to potassium-enriched salt substitution in China: Modeling study. BMJ.. 2020; 369: m824.

⁹Bhat S, Marklund M, Henry ME, et al.. A systematic review of dietary salt sources around the world. Adv Nutr.. 2020; 11: 677-686.