Clinical trial NCT02653560: Value of Liquid Potassium Magnesium Citrate in Controlling Hypertension
Official title: Value of Liquid Potassium Magnesium Citrate in Controlling Hypertension
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE4
Conditions: Hypertension
Keywords: Potassium
Magnesium
Citrate
DASH
Lead sponsor: University of Texas Southwestern Medical Center
Sponsor class: OTHER
First posted: 2016-01-12
Enrollment: 30
Sex: ALL
Minimum age (years): 21
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: TREATMENT

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.

Eligibility criteria: Inclusion Criteria:

* Patients with pre- or Stage I hypertension, with systolic blood pressure of 120-159 mm and diastolic of 80-99 mm
* Age \> 21 years of age

Exclusion Criteria:

* Diabetes mellitus,
* Renal impairment (serum creatinine \> 1.4 mg/dL),
* Any heart diseases such as congestive heart failure or sustained arrhythmia,
* Chronic NSAID use,
* Treatment with diuretics,
* Gastroesophageal reflux disease (GERD) requiring treatment with acid reducing agents or antacid more than once a week,
* Esophageal-gastric ulcer,
* Chronic diarrhea
* Hyperkalemia (serum \> 4.6 mmol/L for patients on Angiotensin converting enzyme (ACE) inhibitors or Angiotensin receptor blockers (ARB), serum K \> 5.0 for patient not on ACE inhibitors or ARBs)
* Liver function test above upper limit of normal range.
* Subjects who require any potassium supplement on a regular basis from any reasons
* Pregnancy
* History of major depression, bipolar disorder, or schizophrenia
* History of substance abuse.

Primary outcomes:
measure: 24-hour Average Systolic Blood Pressure
timeFrame: 4 weeks
Secondary outcomes:
Other outcomes:
Locations:
city: Dallas
country: United States
facility: University of Texas Southwestern Medical Center at Dallas
state: Texas
Study officials:
affiliation: UT Southwestern Medical Center
name: Wanpen Vongpatanasin, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: He FJ, Markandu ND, Coltart R, Barron J, MacGregor GA. Effect of short-term supplementation of potassium chloride and potassium citrate on blood pressure in hypertensives. Hypertension. 2005 Apr;45(4):571-4. doi: 10.1161/01.HYP.0000158264.36590.19. Epub 2005 Feb 21.
citation: Conlin PR, Erlinger TP, Bohannon A, Miller ER 3rd, Appel LJ, Svetkey LP, Moore TJ. The DASH diet enhances the blood pressure response to losartan in hypertensive patients. Am J Hypertens. 2003 May;16(5 Pt 1):337-42. doi: 10.1016/s0895-7061(03)00056-6.
citation: He FJ, Marciniak M, Carney C, Markandu ND, Anand V, Fraser WD, Dalton RN, Kaski JC, MacGregor GA. Effects of potassium chloride and potassium bicarbonate on endothelial function, cardiovascular risk factors, and bone turnover in mild hypertensives. Hypertension. 2010 Mar;55(3):681-8. doi: 10.1161/HYPERTENSIONAHA.109.147488. Epub 2010 Jan 18.
citation: Lin PH, Aickin M, Champagne C, Craddick S, Sacks FM, McCarron P, Most-Windhauser MM, Rukenbrod F, Haworth L; Dash-Sodium Collaborative Research Group. Food group sources of nutrients in the dietary patterns of the DASH-Sodium trial. J Am Diet Assoc. 2003 Apr;103(4):488-96. doi: 10.1053/jada.2003.50065.
citation: Lind L, Lithell H, Pollare T, Ljunghall S. Blood pressure response during long-term treatment with magnesium is dependent on magnesium status. A double-blind, placebo-controlled study in essential hypertension and in subjects with high-normal blood pressure. Am J Hypertens. 1991 Aug;4(8):674-9. doi: 10.1093/ajh/4.8.674.
citation: China Salt Substitute Study Collaborative Group. Salt substitution: a low-cost strategy for blood pressure control among rural Chinese. A randomized, controlled trial. J Hypertens. 2007 Oct;25(10):2011-8. doi: 10.1097/HJH.0b013e3282b9714b.
citation: Sellmeyer DE, Schloetter M, Sebastian A. Potassium citrate prevents increased urine calcium excretion and bone resorption induced by a high sodium chloride diet. J Clin Endocrinol Metab. 2002 May;87(5):2008-12. doi: 10.1210/jcem.87.5.8470.