Stroke reduction with replacement of salt by a salt substitute
SSaSS: Salt Substitute and Stroke Study into the effect of salt substitutes on cardiovascular events and death
Presented at the ESC congress 2021 by: Prof. Bruce Neal, MD, PhD - Sydney, Australia
Introduction and methods
The Salt Substitute and Stroke Study (SSaSS) was an open, cluster-randomized study that compared the effect of a salt substitute (75% NaCl + 25% KCl) with regular salt (100% NaCl) on stroke, CV events, mortality and clinical hyperkalemia.
The trial was conducted in 600 villages in rural areas of China. A total of 20,995 adults with either previous stroke or aged ≥60 years with poorly controlled hypertension were enrolled in the study. Participants were cluster-randomized by village in a 1:1 ratio to receive a free salt substitute or continued use of regular salt. Participants that received the salt substitute were encouraged to use it for all cooking, food preservation and seasoning. To maximize sodium reduction, participants in the salt substitute group were also encouraged to use the salt substitute more sparingly that they usually used salt. Average age was 65.4 years, 49.5% were female, 72.6% had a history of stroke, and 88.4% had a history hypertension. The primary endpoint was stroke. Secondary outcomes included MACE (non-fatal stroke, non-fatal ACS, vascular death) and total mortality. Clinical hyperkalemia was investigated as a safety outcome. Average follow-up was 4.74 years. During follow-up ~3000 strokes, ~4000 deaths and ~5000 MACE were recorded.
- The risk of stroke was significantly reduced by 14% with the salt substitute compared to regular salt (rate ratio [RR] 0.86, 95%CI 0.77-0.96, P=0.006).
- MACE and total mortality were also significantly reduced with the salt substitute compared to regular salt (MACE: RR 0.87, 95%CI 0.80-0.94, P<0.001; total mortality: RR 0.88, 95%CI 0.82-0.95, P<0.001).
- There was no increased risk of serious adverse events attributed to clinical hyperkalemia with salt substitute compared to regular salt (RR 1.04, 95% 0.80-1.37, P=0.76).
Substitution of regular salt with the salt substitute reduced the risk of stroke, MACE and death. There was no increased risk of clinical hyperkalemia.
Prof. Bruce Neal said that the effects observed in this study are very likely generalizable to other populations, because the way that the human body manages sodium and potassium and the associations with blood pressure are highly constant across diverse populations around the world. He also said that almost everyone (except those with serious kidney disease) could safely switch to a salt substitute.
-Our reporting is based on the information provided at the ESC Congress –