In patients with a history of stroke, salt substitution is safe, and the risks of death and recurring stroke are reduced, a new cluster trial shows. Xiong Ding, MPH, of Wuhan University, Wuhan, China, and colleagues from China, Australia and the UK, presented these results in a manuscript published Wednesday online in JAMA: Cardiology. Patients who have a history of stroke are at greater risk for recurring stroke and death. Control of hypertension and blood pressure (BP) are significant contributors in this risk profile. Many trials have demonstrated how the reduction of dietary sodium and increasing dietary potassium can improve BP, but salt substitutes — specifically the partial replacement of sodium chloride with potassium chloride — have not yet been thoroughly studied in this patient population on a large scale. The investigators in this study examined the impacts salt versus salt substitutes on the occurrence of stroke and death in patients with a history of stroke. The Salt Substitute and Stroke Study (SSaSS) was an open label, cluster randomized trial conducted across 600 towns in northern China. Between November 2023 and August 2024, data were analyzed, and recurrent stroke was the primary outcome for this study. A total of 15,249 patients with self-reported prior stroke (mean age=64.1 years, 45.9% female) were included in the trial. Patients were assigned to the salt substitute group (75% sodium chloride, 25% potassium chloride by mass) or regular salt. The median follow-up was 61.2 months. Between the two groups, the mean difference in BP was –2.05 mm Hg (95% confidence interval [CI]: -3.03 to –1.08 mm Hg). Researchers recorded a total of 2,735 recurrent strokes (fatal=691, nonfatal=2,044) and 3,242 deaths. In the salt substitute group, recurrent stroke was significantly lower (rate ratio [RR]=0.86, 95% CI=0.77-0.95, p=0.005) compared with the salt group. Larger effects were observed on hemorrhagic stroke (relative reduction=30%, p=0.002). Additionally, death rates were lower in the salt substitute group compared with the salt group (RR=0.88, 95% CI=0.82-0.96, p=0.003), where stroke-related deaths had larger effects (relative reduction=21%, p=0.01). Hyperkalemia showed no between-group differences (RR=1.01, 95% CI=0.74-1.38, p=0.96). Overall, for patients with a history of stroke, rates of recurring stroke and mortality were reduced more in patients using dietary salt substitutes compared with patients using salt. Sources: Ding X, Zhang X, Huang L. Salt Substitution and Recurrent Stroke and Death: A Randomized Clinical Trial. JAMA Cardiol. 2025 Feb 5 (Article in Press). Image Credit: Sharif– stock.adobe.com