Less sodium, more potassium => lower CV risk

[Eddy Edson]

Big new study firms up the connection between reducing sodium/increasing potassium intake and reducing CV risk.

https://www.nejm.org/doi/full/10.1056/NEJMoa2105675

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. opens in new tab.)


Quick take video:

Salt Substitution and Cardiovascular Events and Death | NEJM

Quick Take Video Summary from The New England Journal of Medicine — Salt Substitution and Cardiovascular Events and Death

www.nejm.org

 

[Eddy Edson]

Seems like the intervention increased potassium more than it reduced sodium, so I guess the headline here is more like "increasing potassium reduces CV risk".

https://twitter.com/x/status/1440407939055902725

 

[Gwynn]

Really interesting to me. I will look into it further. Thank you

 

[trophywench]

I frequently have had low serum sodium and OK potassium which causes the GP and D consultant consternation so don't think I should be messing about with my intake of either thanks. I've got to die of something anyway so unless somebody actually tells me I need to do X or Y pdq I'm happy to keep me as I am.

 

[Gwynn]

Hmm just been looking around the internet. It's not as clear cut as it could be.

However, interestingly, they use pottasium chloride as a preferred means of execution in America. Although I suspect in a rather large dose.

Not sure I should be meddling with it, except pottasium enriched, or is it called sodium reduced salt can be purchased in most supermarkets and I have yet to hear of anyone being harmed by any of these products. So maybe its ok.

Looking at the foods that I currently and commonly eat I consume plenty of pottasium already. So I guess its a non issue for me.

Interestingly both my pulse and blood pressure are always on the lower side. And my pulse has been very low more recently, down to below 43 bpm on occasion. But no other effects seen. Probably a duff sensor unit.

 

[mikeyB]

The use of potassium chloride in killing people uses concentrations about a hundred times higher than you could get even with the most salt loving people. It just stops the heart. The only folk who should avoid this salt substitute are those with a touch of renal failure, or, indeed with full bore renal failure.