POTASSIUM-RICH SALT SUBSTITUTES IN KIDNEY TRANSPLANT RECIPIENTS

NCT07178964 | Not Yet Recruiting

• 1 other identifier: 20250138
• Study Type: interventional
• Target: 80
• Locations: 1 country
• Sites: 1

Brief Summary

Excessive sodium intake and inadequate potassium intake in the diet are known risk factors for the development of arterial hypertension and an increased risk of cardiovascular events. Data from randomized controlled trials show that the use of salt substitutes with reduced sodium and increased potassium content represent an effective way to reduce dietary sodium intake, blood pressure and the occurrence of cardiovascular events. Patients adhere well to the use of salt substitutes as they do not have to change their daily cooking and seasoning habits and the taste is comparable to that of regular salt. The World Health Organization (WHO) also suggests the use of salt substitutes as an acceptable strategy for reducing dietary salt intake and thus lowering blood pressure and the burden of cardiovascular disease. Recommendations for the use of salt substitutes are not uniform, primarily because of the potential risk of adverse events with increased potassium intake in some individuals, such as patients with advanced chronic kidney disease (CKD), patients receiving potassium-sparing diuretics, and patients receiving potassium supplements. Nephrology guidelines rarely comment on the use of potassium-rich salt substitutes or discourage their use in patients with advanced stage 4 and 5 CKD, with the exception of Chinese guidelines, which mention the use of potassium-rich salt substitutes in CKD patients not on dialysis depending on serum potassium levels. CKD patients have largely been excluded from clinical trials of potassium-rich salt substitutes, so there is insufficient data on their safety and efficacy in CKD patients. In this randomized controlled trial, we will investigate the effects of using potassium-enriched salt substitutes on blood pressure control and serum potassium levels in kidney transplant recipients. In the intervention group, patients will use potassium-enriched salt substitutes at home in a ratio of 75% sodium chloride and 25% potassium chloride instead of regular table salt (100% sodium chloride) for cooking and seasoning food. In the control group, patients will use regular salt at home for cooking and seasoning food. The intervention and control groups will each include 40 to 50 patients who will be monitored for 12 weeks. The study's main focus will be the change in serum potassium and blood pressure before and after the intervention. We expect to confirm the positive effects of potassium-enriched salt substitutes on blood pressure in kidney transplant recipients without causing undesirable hyperkalemia.

Conditions

Hypertension Arterial; Kidney Transplant

Outcome Measures

Primary Outcomes (1)

• Hyperkalemia

  Change in serum potassium in mmol/l after using potassium-enriched salt-substitutes for cooking and seasoning food at home for 12 weeks

  12 weeks.

Secondary Outcomes (11)

• Change in systolic blood pressure

  12 weeks

• Change in diastolic blood pressure

  12 weeks

• Change in average systolic 24-hour blood pressure

  12 weeks

• Change in average diastolic 24-hour blood pressure

  12 weeks

• Change in average daily systolic blood pressure

  12 weeks

Study Arms (2)

Potassium-enriched salt-substitute arm

EXPERIMENTAL

The patients in this arm will use potassium-enriched salt-substitutes for cooking and seasoning food in their home environment.

Other: Potassium-enriched salt-substitute

Regular table salt arm

SHAM COMPARATOR

The patients in this arm will use regular table salt for cooking and seasoning food in their home environment.

Other: Regular table salt

Interventions

Potassium-enriched salt-substitute OTHER

The patients in the experimental group will use potassium-enriched salt-substitutes for cooking and seasoning food in their home environment. Potassium-enriched salt-substitutes will contain 25% potassium chloride nad 75% sodium chloride.

Potassium-enriched salt-substitute arm

Regular table salt OTHER

Patients in this arm will use regular table salt (100 % sodium chloride) for cooking and seasoning food in their home environment.

Regular table salt arm

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• patients with a transplanted kidney ≥ 3 months post kidney-transplant
• a functioning transplanted kidney with estimated glomerular filtration rate (eGFR) according to CKD/EPI equation of at least 25 ml/min
• Elevated blood pressure/hypertension at the time of examination at the Kidney Transplantation Center outpatient clinic, determined by standardized blood pressure measurement (RR ≥ 130/80 mmHg)
• Age ≥ 18 years

You may not qualify if:

• eGFR according to CKD/EPI equation below 25 ml/min
• serum potassium \> 5 mmol/l
• history of unexplained hyperkalemia
• pregnancy or planning of pregnancy
• inability to provide informed consent or to participate in the study (mental retardation, psychiatric illness in an uncontrolled phase)
• multiple organ transplantation
• Consuming most of daily meals outside the home environment

Sponsors & Collaborators

• University Medical Centre Ljubljana: lead

Study Sites (1)

University Medical Centre Ljubljana

Ljubljana, 1000, Slovenia

Location

Related Publications (11)

• Chia YC, He FJ, Cheng MH, Shin J, Cheng HM, Sukonthasarn A, Wang TD, Van Huynh M, Buranakitjaroen P, Sison J, Siddique S, Turana Y, Verma N, Tay JC, Schlaich MP, Wang JG, Kario K; HOPE-Asia Network. Role of dietary potassium and salt substitution in the prevention and management of hypertension. Hypertens Res. 2025 Jan;48(1):301-313. doi: 10.1038/s41440-024-01862-w. Epub 2024 Oct 29.

  PMID: 39472546 BACKGROUND

• Romero-Gonzalez G, Rodriguez-Chitiva N, Canameras C, Paul-Martinez J, Urrutia-Jou M, Troya M, Soler-Majoral J, Graterol Torres F, Sanchez-Baya M, Calabia J, Bover J. Albuminuria, Forgotten No More: Underlining the Emerging Role in CardioRenal Crosstalk. J Clin Med. 2024 Jan 29;13(3):777. doi: 10.3390/jcm13030777.

  PMID: 38337471 BACKGROUND

• Xu X, Zeng L, Jha V, Cobb LK, Shibuya K, Appel LJ, Neal B, Schutte AE. Potassium-Enriched Salt Substitutes: A Review of Recommendations in Clinical Management Guidelines. Hypertension. 2024 Mar;81(3):400-414. doi: 10.1161/HYPERTENSIONAHA.123.21343. Epub 2024 Jan 29.

  PMID: 38284271 BACKGROUND

• Natale P, Mooi PK, Palmer SC, Cross NB, Cooper TE, Webster AC, Masson P, Craig JC, Strippoli GF. Antihypertensive treatment for kidney transplant recipients. Cochrane Database Syst Rev. 2024 Jul 31;7(7):CD003598. doi: 10.1002/14651858.CD003598.pub3.

  PMID: 39082471 BACKGROUND

• Visser WJ, Gritter M, Hoorn EJ. Dietary Potassium in Chronic Kidney Disease: Do Not Restrict the Evidence. J Ren Nutr. 2021 Nov;31(6):552-553. doi: 10.1053/j.jrn.2020.12.012. Epub 2021 Mar 12. No abstract available.

  PMID: 33715954 BACKGROUND

• Daneshzad E, Hatami SE, Sobhani S, Ghoreshi B, Khonsari NM, Shahrestanaki E, Pezeshki M, Kiaee ZF, Assar O, Qorbani M. Effects of potassium-enriched salt substitutes on blood pressure in Iranian hypertensive patients: the protocol for a randomised, double-blind controlled trial. BMJ Open. 2025 Jun 25;15(6):e090472. doi: 10.1136/bmjopen-2024-090472.

  PMID: 40562554 BACKGROUND

• Tsai YC, Tsao YP, Huang CJ, Tai YH, Su YC, Chiang CE, Sung SH, Chen CH, Cheng HM. Effectiveness of salt substitute on cardiovascular outcomes: A systematic review and meta-analysis. J Clin Hypertens (Greenwich). 2022 Sep;24(9):1147-1160. doi: 10.1111/jch.14562.

  PMID: 36196475 BACKGROUND

• Bernabe-Ortiz A, Sal Y Rosas VG, Ponce-Lucero V, Cardenas MK, Carrillo-Larco RM, Diez-Canseco F, Pesantes MA, Sacksteder KA, Gilman RH, Miranda JJ. 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.

  PMID: 32066973 BACKGROUND

• Eleftheriadis G, Naik MG, Osmanodja B, Halleck F, Schrezenmeier E, Liefeldt L, Choi M, Bachmann F, Avaniadi DP, von Hoerschelmann E, Lucht C, Zaks M, Duettmann W, Budde K. Office or home versus 24-h blood pressure measurement in stable kidney transplant recipients. Nephrol Dial Transplant. 2024 Oct 30;39(11):1890-1899. doi: 10.1093/ndt/gfae076.

  PMID: 38549427 BACKGROUND

• Tantisattamo E, Molnar MZ, Ho BT, Reddy UG, Dafoe DC, Ichii H, Ferrey AJ, Hanna RM, Kalantar-Zadeh K, Amin A. Approach and Management of Hypertension After Kidney Transplantation. Front Med (Lausanne). 2020 Jun 16;7:229. doi: 10.3389/fmed.2020.00229. eCollection 2020.

  PMID: 32613001 BACKGROUND

• Speer C, Benning L, Morath C, Zeier M, Frey N, Opelz G, Dohler B, Tran TH; Collaborative Transplant Study. Blood Pressure Goals and Outcomes in Kidney Transplant Recipients in an Analysis of the Collaborative Transplant Study. Kidney Int Rep. 2024 Dec 6;10(3):780-790. doi: 10.1016/j.ekir.2024.12.004. eCollection 2025 Mar.

  PMID: 40225383 BACKGROUND

MeSH Terms

Conditions

Hypertension

Condition Hierarchy (Ancestors)

Vascular Diseases; Cardiovascular Diseases

Study Officials

• Tanja Belcic Mikic, MD, PhD, FEBTM

  University Medical Centre Ljubljana

  PRINCIPAL INVESTIGATOR

• Miha Arnol, Professor, MD, PhD, FEBTM

  University Medical Centre Ljubljana

  STUDY DIRECTOR

Central Study Contacts

Tanja Belcic Mikic, MD, PhD, FEBTM

CONTACT

+386 1 522 2751; tanja.belcic.mikic@kclj.si

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: MD, PhD, FEBTM

Study Record Dates

• First Submitted: September 10, 2025
• First Posted: September 17, 2025
• Study Start: October 1, 2025
• Primary Completion (Estimated): June 30, 2026
• Study Completion (Estimated): September 30, 2026
• Last Updated: September 17, 2025

Record last verified: 2025-09

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF, CSR, ANALYTIC CODE
• Time Frame: 30.09.2026-30.09.2027

Locations

SL (1)