Logo: to the web site of Uppsala University

Background: Salt substitution (ie, replacement of table and cooking salt with potassium-enriched salt substitutes) is a promising strategy to reduce blood pressure and prevent cardiovascular disease, particularly in countries like India where there is high sodium intake, mainly from discretionary salt, and low potassium intake. Life-threatening hyperkalemia from increased potassium intake is a postulated concern for individuals with chronic kidney disease.

Methods: We used comparative risk assessment models to estimate the number of (1) cardiovascular deaths averted due to blood pressure reductions; (2) potential hyperkalemia-related deaths from increased potassium intake in individuals with advanced chronic kidney disease; and (3) net averted deaths from nationwide salt substitution in India. We evaluated a conservative scenario, based on a large, long-term pragmatic trial in rural China; and an optimistic scenario informed by our recent trial in India. Sensitivity analyses were conducted to assess the robustness of the findings.

Results: In the conservative scenario, a nationwide salt substitution intervention was estimated to result in approximate to 214 000 (95% uncertainty interval, 92 764-353 054) averted deaths from blood pressure reduction in the total population and approximate to 52 000 (22 961-80 211) in 28 million individuals with advanced chronic kidney disease, while approximate to 22 000 (15 221-31 840) hyperkalemia-deaths might be caused by the intervention. The corresponding estimates for the optimistic scenario were approximate to 351 000 (130 470-546 255), approximate to 66 000 (24 925-105 851), and approximate to 9000 (4251-14 599). Net benefits were consistent across sensitivity analyses.

Conclusions: Modeling nationwide salt substitution in India consistently estimated substantial net benefits, preventing around 8% to 14% of annual cardiovascular deaths. Even allowing for potential hyperkalemia risks there were net benefits estimated for individuals with chronic kidney disease.