Effects of potassium-enriched salt substitutes on blood pressure in Iranian hypertensive patients: the protocol for a randomised, double-blind controlled trial.

Abstract

Potassium-enriched salt substitutes have favourable effects on blood pressure, but it has not been tested in Iran. The present protocol is a double-blinded, randomised-controlled trial designed to investigate the effects of potassium-enriched salt substitutes on blood pressure in Iranian hypertensive patients. The primary objectives are to determine the effects on systolic and diastolic blood pressure at 3 months and 6 months. The secondary objectives are to assess the effects on serum levels of potassium, sodium, urea and creatinine; the urinary ratio of sodium to potassium; participants' attitudes toward the use of salt or salt substitutes; the recurrence of hypertensive crisis; and the occurrence and/or reoccurrence of strokes, transient ischaemic attack and cardiovascular accidents. Eligible individuals will receive the usual salt (100% sodium chloride) in the control group or salt substitute (70% sodium chloride and 30% potassium chloride) in the intervention group. A total of 500 hypertensive participants aged 40-65 years will be recruited and randomised to intervention or control groups. Potassium-enriched salt substitution in Iran will be considered to improve CVD complications and prevent deaths. Continuous and categorical baseline characteristics will be tested using the independent t-test and χ² test. The effect of the intervention on primary and secondary outcomes will be assessed using the intention-to-treat method and two-way mixed ANOVA models. This study has been approved by Alborz University of Medical Sciences (0-0-103-6369) and has received ethics approval (IR.ABZUMS.REC.1402.293). We will publish our study findings for peer-reviewed publications, conference presentations and digital stories. IRCT20240121060757N1.