Potassium Supplementation to Reduce Blood Pressure

NCT05412654 | Completed DMC

• 1 other identifier: 221579
• Study Type: interventional
• Target: 40
• Locations: 1 country
• Sites: 1

Brief Summary

The aim of this study is to conduct a definitive trial to assess the efficacy of consuming 1L/day of water rich in potassium to reduce blood pressure in mild to moderately hypertensive adults. The objective is to assess the potential effect of the intervention on reducing systolic blood pressure. This study will comprise of a 4 week, double-blind, parallel randomised controlled trial. Participants will be adults with systolic blood pressure measurements of 130mmHg or greater. The intervention comprises advice to consume bottled water rich in potassium. The comparator will be regular bottled mineral water.This study will recruit 40 people with elevated systolic blood pressure (≥130mmHg) who are not regularly taking antihypertensive medication.

Conditions

Prehypertension

Keywords

Potassium; Blood pressure; Systolic; Randomised

Outcome Measures

Primary Outcomes (1)

• Seated home measured systolic blood pressure mm/Hg

  Blood pressure will me monitored by the participant at home, after detailed instruction are provided by trained researchers over Zoom. Measurements will be taken in duplicate, in the morning and again in the evening (4 times a day total) and the average values will be taken.

  Blood pressure will be taken at three time points through out the 4 weeks.

Secondary Outcomes (2)

• Seated home measured diastolic blood pressure

  Blood pressure will be taken at three time points through out the 4 weeks

• Qualitative semi-structured, part open ended survey of acceptability of trial and reported barriers

  This survey will be administered on the final visit at week 4 of the trial.

Study Arms (2)

High potassium water

EXPERIMENTAL

All participants will be provided with bottled water for the duration of the 4 week intervention to consume 1L/day. The intervention group will receive high potassium water. Participants will be instructed to consume 1 bottle (500 mL) within 2 hours after waking up and 1 bottle (500 mL) within 2 hours before going to bed (total 1L/day). Participants will continue with the same diet and exercise patterns in their daily life similar to before participating in the study, for the whole length of the intervention.

Dietary Supplement: High potassium water

Low potassium control water

PLACEBO COMPARATOR

All participants will be provided with bottled water for the duration of the 4 week intervention to consume 1L/day. The control group will receive regular bottled mineral water. Participants will be instructed to consume 1 bottle (500 mL) within 2 hours after waking up and 1 bottle (500 mL) within 2 hours before going to bed (total 1L/day). Participants will continue with the same diet and exercise patterns in their daily life similar to before participating in the study, for the whole length of the intervention.

Dietary Supplement: Control low potassium water

Interventions

High potassium water DIETARY_SUPPLEMENT

High potassium water Potassium 6.2 mg/100ml

High potassium water

Control low potassium water DIETARY_SUPPLEMENT

Control water Potassium 0.2 mg/100ml

Low potassium control water

Eligibility Criteria

• Age: 20 Years - 64 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Willing and able to provide informed consent
• Between 20 to 64 years old
• English speaking
• Adults who are not receiving antihypertensive pharmacological treatment
• Recent (within 6 months) and latest systolic blood pressure measurement ≥130mmHg and/or diastolic ≥85 mmHg
• Have access to internet and equipment for video calling
• Able to post samples and equipment to OxBCNH
• Physically able to take own body measurements and blood pressure

You may not qualify if:

• Participation in another research study
• Unable to read and understand the instructions provided in English
• Unable to comply with experimental procedures or not follow testing safety guidelines
• People with cardiovascular conditions: heart attack or stroke within the last 3 months, heart failure of grade II New York Heart Association and more severe, or prolonged QT syndrome, angina, arrhythmia or atrial fibrillation.
• Uncontrolled type 2 diabetes (HbA1c\> 9%)
• Type 2 diabetes controlled using exogenous insulin
• Previous or current diagnosis of diabetes complications such as nephropathy, retinopathy and neuropathy.
• People with type 1 diabetes
• Currently on any medication that may lead to hyperkalemia or fluid retention
• Currently being assessed for diagnosis of hypertension (not receiving treatment for high blood pressure)
• Already on clinician/HCP supervised diet or restricted diet
• They are planning on going away from home (holiday or other) during the 4 week intervention period and will not be able to take water during this time.
• Currently prescribed antihypertensive medications, or have been in the last 6 weeks
• Chronic kidney disease stage 1 (G1A2 or G1A3), 2 (G2A2 or G2A3), 3a, 3b, 4 or 5 based on UKKA (we will ask whether participants have been diagnosed with kidney disease by a clinician based on this criteria)
• They are planning to go on a diet or begin taking supplements containing potassium during the intervention

Sponsors & Collaborators

• Oxford Brookes University: lead
• Suntory Beverage & Food Limited: collaborator

Study Sites (1)

Oxford Brookes University

Oxford, Oxfordshire, ox30bp, United Kingdom

Location

MeSH Terms

Conditions

Prehypertension; Systolic Murmurs

Condition Hierarchy (Ancestors)

Vascular Diseases; Cardiovascular Diseases; Heart Murmurs; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Senior Lecturer in Nutrition

Model Details: Double blinded randomised controlled trial

Study Record Dates

• First Submitted: May 31, 2022
• First Posted: June 9, 2022
• Study Start: July 30, 2022
• Primary Completion: December 1, 2023
• Study Completion: December 1, 2023
• Last Updated: April 4, 2024

Record last verified: 2024-04

Data Sharing

• IPD Sharing: Will not share

Locations

GB (1)