To determine the effect of (1) increased sodium intake and (2) increased potassium intake on blood pressure, vascular function and renal function in untreated (pre)hypertensive subjects.
This is a randomized, double-blind, placebo controlled cross-over feeding study.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
BASIC_SCIENCE
Masking
TRIPLE
Enrollment
40
Sodium Chloride (provided by Microz, Geleen, Netherlands): 8 capsules per day which equals a sodium intake of 3 grams.
Potassium Chloride (provided by Microz, Geleen, Netherlands): 8 capsules per day which equals a potassium intake of 3 grams.
Placebo (cellulose, provided by Microz, Geleen, Netherlands): 8 capsules per day.
Wageningen University
Wageningen, Netherlands
Change in Endothelium-dependent flow-mediated dilation comparing (1) high sodium, low potassium intake and (2) low sodium, high potassium intake with low sodium, low potassium intake.
Ultra-sonography (brachial artery) + Picus system
Time frame: Baseline at week 1 (t=0). After intervention period 1 at week 5 (t=1). After intervention period 2 at week 9 (t=2). After intervention period 3 at week 13 (t=3)
Change in blood pressure comparing (1) high sodium, low potassium intake and (2) low sodium, high potassium intake with low sodium, low potassium intake.
Includes: Office BP (Dinamap, 4 consecutive measurements with 2-min intervals) ABPM (Spacelab; 1x24h, at baseline, week 5, week 9, week 13)
Time frame: Screening. Baseline at week 1 (t=0). After intervention period 1 at week 5 (t=1). After intervention period 2 at week 9 (t=2). After intervention period 3 at week 13 (t=3)
Change in Pulse Wave Velocity comparing (1) high sodium, low potassium intake and (2) low sodium, high potassium intake with low sodium, low potassium intake.
Device: SphygmoCor (tonometry) Parameters: Pulse Wave Velocity and at baseline, week 5, week 9 and week 13
Time frame: Baseline at week 1 (t=0). After intervention period 1 at week 5 (t=1). After intervention period 2 at week 9 (t=2). After intervention period 3 at week 13 (t=3)
Change in vasomotion comparing (1) high sodium, low potassium intake and (2) low sodium, high potassium intake with low sodium, low potassium intake.
Device: PeriFlux 5000 (Perimed, Sweden0
Time frame: Baseline at week 1 (t=0). After intervention period 1 at week 5 (t=1). After intervention period 2 at week 9 (t=2). After intervention period 3 at week 13 (t=3)
Change in Biomarkers of endothelial function comparing (1) high sodium, low potassium intake and (2) low sodium, high potassium intake with low sodium, low potassium intake.
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Plasma analysis of endothelin-1, ADMA, MCP-1, sVCAM-1, sICAM-1, sE-selectin, sTM, CRP, SAA, IL-6, IL-8, TNF-α, vWF, nitric oxide
Time frame: Baseline at week 1 (t=0). After intervention period 1 at week 5 (t=1). After intervention period 2 at week 9 (t=2). After intervention period 3 at week 13 (t=3)
Change in renal function comparing (1) high sodium, low potassium intake and (2) low sodium, high potassium intake with low sodium, low potassium intake.
eGFR, serum creatinine (at screening also used as safety parameter)
Time frame: Screening. Baseline at week 1 (t=0). After intervention period 1 at week 5 (t=1). After intervention period 2 at week 9 (t=2). After intervention period 3 at week 13 (t=3)
Change in cardiovascular parameters in plasma comparing (1) high sodium, low potassium intake and (2) low sodium, high potassium intake with low sodium, low potassium intake.
Total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, insulin and glucose (at screening also used as safety parameter)
Time frame: Screening. Baseline at week 1 (t=0). After intervention period 1 at week 5 (t=1). After intervention period 2 at week 9 (t=2). After intervention period 3 at week 13 (t=3)
Liver function parameters
Montoring liver function parameters for safety: includes ALAT, ASAT and ɣ-GT
Time frame: Screening. Baseline at week 1 (t=0). After intervention period 1 at week 5 (t=1). After intervention period 2 at week 9 (t=2). After intervention period 3 at week 13 (t=3)
24-hour urinary mineral excretions
Sodium and potassium (as compliance markers)
Time frame: Screening. Baseline at week 1 (t=0). After intervention period 1 at week 5 (t=1). After intervention period 2 at week 9 (t=2). After intervention period 3 at week 13 (t=3)
24-hour excretion of protein, albumin and creatinine
In addition, protein is assessed in spot urine during screening using a dipstick test
Time frame: Screening. Baseline at week 1 (t=0). After intervention period 1 at week 5 (t=1). After intervention period 2 at week 9 (t=2). After intervention period 3 at week 13 (t=3)
Adverse events
Patient diary for occasions of illness, hospitalizations, medication use and other information on potential side effects
Time frame: Every day
Anthropometric measurements
Body weight (weekly), height (only at baseline), waist circumference (baseline and every 4 weeks)
Time frame: Screening. Baseline at week 1 (t=0). After intervention period 1 at week 5 (t=1). After intervention period 2 at week 9 (t=2). After intervention period 3 at week 13 (t=3)
Heart rate
Dinamap, 4 consecutive measurements with 2-min intervals
Time frame: Screening. Baseline at week 1 (t=0). After intervention period 1 at week 5 (t=1). After intervention period 2 at week 9 (t=2). After intervention period 3 at week 13 (t=3)
Food frequency questionnaire
Time frame: Screening
Change in Pulse Wave Analysis comparing (1) high sodium, low potassium intake and (2) low sodium, high potassium intake with low sodium, low potassium intake.
Device: SphygmoCor (tonometry)
Time frame: Baseline at week 1 (t=0). After intervention period 1 at week 5 (t=1). After intervention period 2 at week 9 (t=2). After intervention period 3 at week 13 (t=3)