Conditions: Hypertension
Keywords: Potassium Magnesium Citrate DASH
Allocation: RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 30
Healthy volunteers: no

Brief summary:
In the DASH (Dietary Approaches to Stop Hypertension) trials, a diet rich in fruits, vegetables, nuts and dairy products, and limited in fat content, was shown to be useful in controlling hypertension. Key components of such a diet are potassium, magnesium and alkali, each of which has been implicated in lowering blood pressure. Whether a liquid formulation of potassium-magnesium citrate will result in equivalent BP effect as the DASH diet is unknown.

Detailed description:
The DASH diet is rich in potassium and magnesium. It is also high in alkali content, since the anions are provided mostly by citrate rather than chloride. Considerable data are already available in the literature invoking a protective role on hypertension of potassium, magnesium and alkali.

In this protocol, the investigators want to test the hypothesis that liquid potassium-magnesium citrate (KMgCit) as a pharmaceutical formulation could serve as a surrogate for the DASH diet, and would lower blood pressure among patients with pre- or Stage I hypertension on their customary diet.

Each subject will participate in all four phases, chosen in random order. The four phases will be: Placebo Phase (microcrystalline cellulose in water), Potassium Chloride Phase (potassium chloride powder in water), Potassium Citrate Phase (potassium citrate powder in water), KMgCit Phase (KMgCit powder in water) During each phase, subjects will receive one of the test drugs for 4 weeks, followed by at least 1 week of withdrawal. Change in 24 hr BP, office BP will be measured at baseline and after each phase. Central aortic blood pressure and carotid-femoral pulse wave velocity, -terminal-telopeptide (CTX), 24 hr urine electrolytes will be measured at 4 weeks in each phase.

Arms:
arm 1: Potassium magnesium citrate will be prepared by mixing potassium citrate, magnesium citrate and/or citric acid by Meta Pharm Development. The content of each sachet will be dissolved in 250 ml water and will be drunk with breakfast and again with dinner during the KMgCit Phase, to deliver 40 meq K, 20 meq Mg and 74 meq citrate per day for 4 weeks arm 2: A special sachet formulation containing 20 meq K/sachet will be made for the study by Meta Pharm Development. The contents of a sachet will be added to 250 ml water and drunk with breakfast and dinner, to deliver 40 meq K (as citrate) per day during the Potassium Citrate Phase for 4 weeks. arm 3: Potassium chloride will contain 20 meq KCl per sachet. During the Potassium Chloride Phase, subjects will dissolve the content of each sachet in 250 ml water and ingest it with breakfast and again with dinner, to deliver 40 meq K (as chloride) per day for 4 weeks arm 4: Placebo will comprise microcrystalline cellulose, equivalent in volume in each sachet as other test products. During the Placebo Phase, subjects will dissolve the entire content of a sachet in 250 ml water and drink it with breakfast and again with dinner for 4 weeks.

Interventions: intervention 1: Potassium chloride powder intervention 2: Potassium magnesium Citrate (KMgCit) intervention 3: Potassium citrate powder intervention 4: Placebo
Intervention descriptions: intervention 1: None intervention 2: None intervention 3: None intervention 4: None

Protocol document: