The purpose of this study is to determine the effect of potassium chloride and potassium bicarbonate on blood pressure and also to determine whether increasing potassium intake has beneficial effects on the surrogate markers of target organ damage in cardiovascular disease, as well as on bone health.

Condition	Intervention	Phase
Hypertension	Behavior: Potassium supplementation	Phase III

Further Study Details: 

Primary Outcomes: Blood pressure and markers of target organ damage and bone health at 4 weeks of potassium supplementation.
Secondary Outcomes: Comparisons among different treatments in blood pressure and markers of target organ damage and bone health.
Expected Total Enrollment:  45

Randomised trials have shown that increasing potassium intake lowers blood pressure. However, most previous trials used potassium chloride. Whereas, potassium in fruits and vegetables is not a chloride salt, but a mixture of potassium phosphate, sulphate, citrate, and many organic anions, most of which are precursors of potassium bicarbonate. It is unclear whether non-chloride salt of potassium has greater or lesser effect on blood pressure compared to potassium chloride.

Experimental studies in animals and epidemiological studies in humans suggest that a high potassium intake may have beneficial effects on the cardiovascular system and the kidney, independent of its effect on blood pressure, and also reduce the risk of osteoporosis.

We propose to carry out a randomised double-blind trial to compare potassium bicarbonate with potassium chloride looking at their effect on blood pressure, and also to determine whether these potassium salts have beneficial effects on the cardiovascular system, kidney and bone health.

Comparisons: potassium chloride vs potassium bicarbonate vs placebo.

Ages Eligible for Study:  18 Years   -   75 Years,  Genders Eligible for Study:  Both

Criteria

Inclusion Criteria:

• Patients with untreated essential hypertension (sitting systolic blood pressure between 140 and 170 mmHg and/or sitting diastolic blood pressure between 90 and 105 mmHg);
• Age 18 - 75 years.

Exclusion Criteria:

• Individuals younger than 18 or older than 75 years;
• Individuals with impaired renal function with plasma creatinine greater than 120 umol/L for non-blacks or 150 umol/L for blacks;
• Individuals with chronic diarrhea, or history of peptic ulcer;
• Individuals with baseline plasma potassium values greater than 5.0 mmol/L;
• Individuals with severe hypertension i.e. blood pressure > 170/105 mmHg;
• Individuals with diabetes mellitus;
• Individuals with any secondary cause of hypertension;
• Individuals with malignancy or liver disease;
• Individuals with ischaemic heart disease or heart failure;
• Females who are pregnant or breast feeding or on the oral contraceptive pill.

Please refer to this study by ClinicalTrials.gov identifier  NCT00160368

Feng J He, PhD      0044-20-8725-5375    fhe@sgul.ac.uk
Graham A MacGregor, MD      0044-20-8725-5774    gmacgregor@sgul.ac.uk

United Kingdom
      St. George''''s University of London,, London,  SW17 0RE,  United Kingdom; Recruiting

Study chairs or principal investigators

Graham A MacGregor, MD,  Principal Investigator,  St George''''s, University of London   

Study ID Numbers:  CH/FR/04.0012
Last Updated:  September 11, 2005
Record first received:  September 8, 2005
ClinicalTrials.gov Identifier:  NCT00160368
Health Authority: United Kingdom: Research Ethics Committee
ClinicalTrials.gov processed this record on 2005-09-13