Effect of salt substitution on community-wide blood pressure and hypertension incidence

Nat Med. 2020 Mar;26(3):374-378. doi: 10.1038/s41591-020-0754-2. Epub 2020 Feb 17.

Abstract

Replacement of regular salt with potassium-enriched substitutes reduces blood pressure in controlled situations, mainly among people with hypertension. We report on a population-wide implementation of this strategy in a stepped-wedge cluster randomized trial (NCT01960972). The regular salt in enrolled households was retrieved and replaced, free of charge, with a combination of 75% NaCl and 25% KCl. A total of 2,376 participants were enrolled in 6 villages in Tumbes, Peru. The fully adjusted intention-to-treat analysis showed an average reduction of 1.29 mm Hg (95% confidence interval (95% CI) (-2.17, -0.41)) in systolic and 0.76 mm Hg (95% CI (-1.39, -0.13)) in diastolic blood pressure. Among participants without hypertension at baseline, in the time- and cluster-adjusted model, the use of the salt substitute was associated with a 51% (95% CI (29%, 66%)) reduced risk of developing hypertension compared with the control group. In 24-h urine samples, there was no evidence of differences in sodium levels (mean difference 0.01; 95% CI (0.25, -0.23)), but potassium levels were higher at the end of the study than at baseline (mean difference 0.63; 95% CI (0.78, 0.47)). Our results support a case for implementing a pragmatic, population-wide, salt-substitution strategy for reducing blood pressure and hypertension incidence.

Publication types

  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Blood Pressure / drug effects*
  • Case-Control Studies
  • Diastole
  • Female
  • Follow-Up Studies
  • Humans
  • Hypertension / epidemiology*
  • Hypertension / physiopathology*
  • Hypertension / urine
  • Incidence
  • Male
  • Peru / epidemiology
  • Potassium / urine
  • Residence Characteristics*
  • Sodium / urine
  • Sodium Chloride, Dietary / adverse effects*
  • Surveys and Questionnaires
  • Systole

Substances

  • Sodium Chloride, Dietary
  • Sodium
  • Potassium