Effects of Magnesium Supplementation on Vascular Structure and Function in Hypertensive Patients (MG600)

This study has been completed.
Sponsor:
Collaborators:
Rio de Janeiro State Research Supporting Foundation (FAPERJ)
Conselho Nacional de Desenvolvimento Científico e Tecnológico
Information provided by (Responsible Party):
Mario Fritsch Neves, Rio de Janeiro State University
ClinicalTrials.gov Identifier:
NCT01151683
First received: June 25, 2010
Last updated: January 4, 2013
Last verified: January 2013
  Purpose

Introduction: Magnesium has been the target for many experimental and clinical studies due to the negative correlation between its serum and intracellular levels and the prevalence of hypertension and other cardiovascular diseases.

Objective: To evaluate the effects of magnesium supplementation in hypertensive patients who are under diuretic treatment, including correlation of clinical and nutritional parameters with structural and functional aspects of the macrocirculation.

Methods: A prospective, randomized, double blind, placebo controlled study will be performed in hypertensive patients, aged between 40 and 65 years-old, in regular use of thiazidic diuretic as antihypertensive monotherapy,. The patients will be divided in two main groups according to supplementation with placebo or magnesium chelate 300mg twice a day (total of 600mg magnesium element per day). Before and after 3 and 6 months of supplementation, the patients will be submitted to clinical and nutritional evaluation, biochemical analysis, including intracellular magnesium measurement, and study of the macrocirculation with ambulatory blood pressure monitoring, analysis of flow-mediated dilation of brachial artery, measurement of carotid intima-media thickness, and carotid-femoral and carotid-radial pulse wave velocity to estimate central and peripheral arterial stiffness.

Analysis: Data will be expressed as mean±epm. Statistical analysis will be performed using software Prism® (GraphPad, version 5.0). Continuous variables in each group will be compared using "t test", and P<0.05 will be considered statistically significant.


Condition Intervention Phase
Hypertension
Endothelial Dysfunction
Dietary Supplement: magnesium
Dietary Supplement: placebo
Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Investigator)
Primary Purpose: Supportive Care
Official Title: Effects of Magnesium Supplementation on Vascular Structure and Function in Hypertensive Patients

Resource links provided by NLM:


Further study details as provided by Rio de Janeiro State University:

Primary Outcome Measures:
  • Improvement of vascular function [ Time Frame: six months ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Improvement of vascular structure and blood pressure [ Time Frame: six months ] [ Designated as safety issue: No ]

Enrollment: 52
Study Start Date: March 2010
Study Completion Date: November 2012
Primary Completion Date: November 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Magnesium
Magnesium chelate 600 mg per day
Dietary Supplement: magnesium
Magnesium chelate, 300mg (2 capsules of 150mg) twice a day, per oral Total of 600mg per day
Other Name: Mg supplement
Placebo Comparator: Placebo
Placebo 4 capsules per day
Dietary Supplement: placebo
Two capsules of placebo per oral twice a day
Other Name: Inactive component

Detailed Description:

The main objective of this study is to evaluate whether magnesium supplementation is associated with improved blood pressure control and whether it has beneficial effects on the vascular structure and function in non-diabetic hypertensive patients who are receiving r diuretic therapy.

Patients will be evaluated in a prospective, randomized, double-blind study and will be admitted to the study if they reach all the inclusion criteria and no exclusion criteria.

In this study, magnesium chelate was chosen because of its better absorption rate. The dosages are different in many protocols but in this project the patients will receive 600 mg of magnesium element daily divided in 300 mg twice a day. The patients will be divided in two main groups according to supplementation with placebo or magnesium chelate 300mg twice a day (total of 600mg magnesium element per day). Before and after 3 and 6 months of supplementation, the patients will be submitted to clinical and nutritional evaluation, biochemical analysis, including intracellular magnesium measurement, and study of the macrocirculation with ambulatory blood pressure monitoring, analysis of flow-mediated dilation of brachial artery, measurement of carotid intima-media thickness, and carotid-femoral and carotid-radial pulse wave velocity to estimate central and peripheral arterial stiffness.

  Eligibility

Ages Eligible for Study:   40 Years to 65 Years
Genders Eligible for Study:   Female
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • Women aged between 40 and 65 years-old
  • Hypertension with mild blood pressure elevation:

    • Systolic BP between 140 and 159mmHg AND/OR
    • Diastolic BP between 90 and 99 mmHg
  • Antihypertensive monotherapy with daily use of thiazidic diuretic, at least in the last 30 days
  • Signature of the Informed Consent by the patient or his legal representative

Exclusion Criteria:

  • Evidences for secondary hypertension
  • Hypertension in stage 2, SBP ≥ 160mmHg and/or DBP ≥ 100mmHg, before the beginning of supplementation
  • Blood pressure > 180 x 100 mmHg in any phase of the study
  • Body mass index > 35 kg/m2
  • Diabetes Mellitus
  • Renal disease presenting glomerular filtration rate < 60ml/min
  • Coronary artery disease clinically evident with previous episode of myocardial infarction and/or myocardial revascularization
  • Clinical signs of heart failure
  • History of stroke
  • Any condition, disease or therapy that, under investigator's opinion, may influence objectives, results, or put in risk the safety of the patients.
  • Pregnancy
  • Patients should not be taking any mineral or vitamin supplements
  • Gastrointestinal conditions
  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT01151683

Locations
Brazil
Department of Clinical Medicine, State University of Rio de Janeiro
Rio de Janeiro, RJ, Brazil, 20551030
Sponsors and Collaborators
Rio de Janeiro State University
Rio de Janeiro State Research Supporting Foundation (FAPERJ)
Conselho Nacional de Desenvolvimento Científico e Tecnológico
Investigators
Principal Investigator: Mario F Neves, MD, PhD State University of Rio de Janeiro
  More Information

No publications provided

Responsible Party: Mario Fritsch Neves, Full Professor, Rio de Janeiro State University
ClinicalTrials.gov Identifier: NCT01151683     History of Changes
Other Study ID Numbers: MG600
Study First Received: June 25, 2010
Last Updated: January 4, 2013
Health Authority: Brazil: Ethics Committee

Keywords provided by Rio de Janeiro State University:
hypertension
endothelial dysfunction

Additional relevant MeSH terms:
Hypertension
Vascular Diseases
Cardiovascular Diseases

ClinicalTrials.gov processed this record on April 17, 2014