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The Effects of Sodium and Potassium on Blood Pressure, Vascular Function and Renal Function (KaNa)

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ClinicalTrials.gov Identifier: NCT01575041
Recruitment Status : Completed
First Posted : April 10, 2012
Last Update Posted : August 10, 2012
Sponsor:
Collaborator:
Information provided by (Responsible Party):

Study Description
Brief Summary:
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.

Condition or disease Intervention/treatment
Hypertension Blood Pressure Vascular Function Renal Function Dietary Supplement: Sodium Drug: Potassium Drug: Placebo

Detailed Description:
This is a randomized, double-blind, placebo controlled cross-over feeding study.

Study Design

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 40 participants
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary Purpose: Basic Science
Official Title: Study on the Effects of Sodium and Potassium on Blood Pressure, Vascular Function and Renal Function in Untreated (Pre)Hypertensive Subjects
Study Start Date : January 2012
Primary Completion Date : July 2012
Study Completion Date : August 2012

Resource links provided by the National Library of Medicine

U.S. FDA Resources

Arms and Interventions

Arm Intervention/treatment
Active Comparator: Sodium
For 4 weeks subjects will consume 3 grams of sodium by the intake of capsules on top of a low-sodium (2 grams of sodium), low-potassium (2 grams of potassium) diet
Dietary Supplement: Sodium
Sodium Chloride (provided by Microz, Geleen, Netherlands): 8 capsules per day which equals a sodium intake of 3 grams.
Active Comparator: Potassium
For 4 weeks subjects will consume 3 grams of potassium by the intake of capsules on top of a low-sodium (2 grams of sodium), low-potassium (2 grams of potassium) diet.
Dietary Supplement: Sodium
Sodium Chloride (provided by Microz, Geleen, Netherlands): 8 capsules per day which equals a sodium intake of 3 grams.
Drug: Potassium
Potassium Chloride (provided by Microz, Geleen, Netherlands): 8 capsules per day which equals a potassium intake of 3 grams.
Placebo Comparator: Placebo
For 4 weeks subjects will consume placebo capsules (content: cellulose) on top of a low-sodium low-potassium diet
Dietary Supplement: Sodium
Sodium Chloride (provided by Microz, Geleen, Netherlands): 8 capsules per day which equals a sodium intake of 3 grams.
Drug: Placebo
Placebo (cellulose, provided by Microz, Geleen, Netherlands): 8 capsules per day.


Outcome Measures

Primary Outcome Measures :
  1. 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. [ 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) ]
    Ultra-sonography (brachial artery) + Picus system


Secondary Outcome Measures :
  1. Change in blood pressure comparing (1) high sodium, low potassium intake and (2) low sodium, high potassium intake with low sodium, low potassium intake. [ 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) ]

    Includes:

    Office BP (Dinamap, 4 consecutive measurements with 2-min intervals) ABPM (Spacelab; 1x24h, at baseline, week 5, week 9, week 13)


  2. 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. [ 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) ]

    Device: SphygmoCor (tonometry)

    Parameters: Pulse Wave Velocity and at baseline, week 5, week 9 and week 13


  3. Change in vasomotion comparing (1) high sodium, low potassium intake and (2) low sodium, high potassium intake with low sodium, low potassium intake. [ 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) ]
    Device: PeriFlux 5000 (Perimed, Sweden0

  4. 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. [ 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) ]
    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

  5. Change in renal function comparing (1) high sodium, low potassium intake and (2) low sodium, high potassium intake with low sodium, low potassium intake. [ 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) ]
    eGFR, serum creatinine (at screening also used as safety parameter)

  6. 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. [ 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) ]
    Total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, insulin and glucose (at screening also used as safety parameter)

  7. Liver function parameters [ 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) ]
    Montoring liver function parameters for safety: includes ALAT, ASAT and ɣ-GT

  8. 24-hour urinary mineral excretions [ 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) ]
    Sodium and potassium (as compliance markers)

  9. 24-hour excretion of protein, albumin and creatinine [ 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) ]
    In addition, protein is assessed in spot urine during screening using a dipstick test

  10. Adverse events [ Time Frame: Every day ]
    Patient diary for occasions of illness, hospitalizations, medication use and other information on potential side effects

  11. Anthropometric measurements [ 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) ]
    Body weight (weekly), height (only at baseline), waist circumference (baseline and every 4 weeks)

  12. Heart rate [ 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) ]
    Dinamap, 4 consecutive measurements with 2-min intervals

  13. Food frequency questionnaire [ Time Frame: Screening ]
  14. 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. [ 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) ]
    Device: SphygmoCor (tonometry)


Eligibility Criteria

Information from the National Library of Medicine

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Ages Eligible for Study:   40 Years to 90 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • (Pre)hypertension, defined as office SBP: 130-159 mmHg;
  • No use of antihypertensive, lipid-lowering, anticoagulant or other cardiovascular medication;
  • Age at start of the ≥ 40 years;
  • Apparently healthy:

    • No reported current or previous metabolic diseases
    • No history of cardiovascular diseases
    • No history of renal, liver or thyroid diseases
    • No history of gastrointestinal diseases
    • No diabetes mellitus
    • Fasting laboratory parameters within normal range: renal function (serum creatinine, ureum), liver function (ALAT, ASAT, ɣ-GT) and serum glucose.

Exclusion Criteria:

  • Body mass index > 40 kg/m²;
  • Smoking
  • Secondary hypertension;
  • Weight loss or weight gain of 5 kg or more during the last 2 months;
  • Usage of non-steroidal anti-inflammatory drugs (aspirin, ibuprofen, naproxen) and not able or willing to stop taking them from at least 4 weeks prior to the study.
  • Medical treatment that may affect blood pressure and not able (or willing) to stop taking them;
  • Women taking oral contraceptives or estrogen replacement therapy
  • Taking nutritional supplements and unwilling to discontinue;
  • Women lactating, pregnant or intend to become pregnant during study;
  • Reported dietary habits: medically prescribed diet, slimming diet;
  • Reported alcohol consumption > 21 units/w (female subjects) or >28 units/w (male subjects);
  • Unable or unwilling to consume one meal every workday at the university, or to consume the prescribed study diet for 13 weeks;
  • Problems with consuming the supplements or following the study guidelines;
  • Unwilling to undergo home or office blood pressure measurements;
  • Recent blood donation i.e. 1 month (male subjects) or 2 months (female subjects) prior to the study and planned donation during the study period;
  • Reported intense sporting activities > 10 h/w;
  • Not agreeing to be informed about unexpected and medically relevant personal test-results
  • Participation in another biomedical trial less than 2 months before the start of the study or at the same time;
  • No informed consent signed.
Contacts and Locations

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01575041


Locations
Netherlands
Wageningen University
Wageningen, Netherlands, 6703 HD
Sponsors and Collaborators
Wageningen University
Top Institute Food and Nutrition
Investigators
Principal Investigator: Johanna M Geleijnse, PhD Wageningen University, Division of Human Nutrition
More Information

Additional Information:
Responsible Party: Wageningen University
ClinicalTrials.gov Identifier: NCT01575041     History of Changes
Other Study ID Numbers: KaNa-trial
First Posted: April 10, 2012    Key Record Dates
Last Update Posted: August 10, 2012
Last Verified: August 2012

Keywords provided by Wageningen University:
sodium
salt
potassium
blood pressure
flow-mediated dilatation
endothelial function
renal function
controlled feeding study
dietary intervention