“Minimal-Advice” on Salt Intake: Results of a Multicentre Pilot Randomised Controlled Trial on Hypertensive Patients

Introduction: A strong and well-known association exists between salt consumption, potassium intake, and cardiovascular diseases. MINISAL-SIIA results showed high salt and low potassium consumption in Italian hypertensive patients. In addition, a recent Italian survey showed that the degree of knowledge and behaviour about salt was directly interrelated, suggesting a key role of the educational approach. Aim: The present multicentre randomised controlled trial study aimed to evaluate the efficacy of a short-time dietary educational intervention by a physician, only during the first visit, on sodium and potassium intake in hypertensive patients. Methods: Two-hundred-thirty hypertensive subjects participating in the MINISAL-SIIA study were enrolled for this study. After the randomisation, the participants were stratified into the educational intervention (EI) group (n = 109) and control group (C) (n = 121). Anthropometric indexes and blood pressure (BP) measurements were taken in the single-centre, and 24-hour urinary sodium (UrNa) and potassium (UrK) excretion were centrally measured. Results: After 3 months, there was a reduction in BP, UrNa, and body weight, and an increase in UrK in EI. By contrast, a lower decrease in BP was found in the C group, and a slight rise in UrNa and no substantial change in UrK were revealed. BP changes were positively and significantly associated with changes in UrNa only in EI. Conclusion: The main results of this trial indicate that a single brief educational intervention by a physician can lead to a reduction in salt intake and BP, and increased potassium consumption in hypertensive patients, without adverse effects. Trail registration: ClinicalTrial.gov registration number: NCT06651437.