Clinical trial NCT05412654: Potassium Supplementation to Reduce Blood Pressure
Official title: Testing the Potential Effect of a Potassium-rich Water Intervention on Blood Pressure in Mild to Moderately Hypertensive Adults: a Double-blind Randomised Controlled Trial
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Prehypertension
Keywords: Potassium
Blood pressure
Systolic
Randomised
Lead sponsor: Oxford Brookes University
Sponsor class: OTHER
Collaborators: name: Suntory Beverage & Food Limited
First posted: 2022-06-09
Enrollment: 40
Sex: ALL
Minimum age (years): 20
Maximum age (years): 64
Standard ages: ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: Double blinded randomised controlled trial
Primary purpose: TREATMENT

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.


Eligibility criteria: Inclusion Criteria:

* 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

Exclusion Criteria:

* 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
* Pregnant women (including women suspected of being pregnant) and breast-feeding woman.

Primary outcomes:
measure: Seated home measured systolic blood pressure mm/Hg
timeFrame: Blood pressure will be taken at three time points through out the 4 weeks.
Secondary outcomes:
measure: Seated home measured diastolic blood pressure
timeFrame: Blood pressure will be taken at three time points through out the 4 weeks
measure: Qualitative semi-structured, part open ended survey of acceptability of trial and reported barriers
timeFrame: This survey will be administered on the final visit at week 4 of the trial.
Other outcomes:
Locations:
city: Oxford
country: United Kingdom
facility: Oxford Brookes University
state: Oxfordshire
Study officials:
References: