How Does Magnesium Status Influence Calcium Homeostasis?

This study is ongoing, but not recruiting participants.
Sponsor:
Collaborators:
Information provided by (Responsible Party):
University of Wisconsin, Madison
ClinicalTrials.gov Identifier:
NCT01593501
First received: May 4, 2012
Last updated: June 16, 2014
Last verified: June 2014
  Purpose

The investigators aim to recruit 60 women who have agreed to participate in an existing randomized, double-blind, placebo-controlled trial (Treatment of Vitamin D Insufficiency, HSC 2009-0055). In this trial, the investigators propose to evaluate the associations between magnesium intake, magnesium stores, fractional magnesium absorption and calcium homeostasis. The investigators will stratify 60 subjects in the sub-study, ensuring that approximately 20 subjects are randomized into each treatment arm (placebo, low-dose and high-dose vitamin D). The investigators already assess calcium homeostasis throughout the study by measuring bone mineral density, fractional calcium absorption, serum and urine calcium levels, among other tests. In the sub-study of 60 women, the investigators will evaluate whether habitually higher magnesium intake increases or decreases fractional calcium absorption. The investigators will evaluate the interplay between magnesium stores, vitamin D levels and serum parathyroid hormone levels. The investigators will directly assess magnesium stores using serum magnesium and 24-hour urine magnesium levels, and will measure magnesium absorption using the dual stable isotope approach.


Condition Intervention Phase
Magnesium Deficiency
Calcium Metabolism Disorders
Dietary Supplement: vitamin D3
Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Investigator)
Primary Purpose: Treatment
Official Title: How Does Magnesium Status Influence Calcium Homeostasis?

Resource links provided by NLM:


Further study details as provided by University of Wisconsin, Madison:

Primary Outcome Measures:
  • Evaluate the associations between magnesium intake, magnesium stores, fractional magnesium absorption and calcium homeostasis. [ Time Frame: 0-12 months ] [ Designated as safety issue: No ]
    To evaluate relationships between magnesium intake and fractional magnesium absorption at baseline and 12 months, among 60 women participating in HSC Protocol 2009-0055, and to assess whether vitamin D therapy influences magnesium absorption among these women. We will also evaluate whether data collected from less than 72 hours of urine following tracer administration permits accurate assessment of fractional magnesium absorption.


Secondary Outcome Measures:
  • Does vitamin D therapy have a differential impact on calcium absorption that is dependent on magnesium stores? [ Time Frame: 0-12 months ] [ Designated as safety issue: No ]
    To assess whether vitamin D therapy has a differential impact on calcium absorption, depending on magnesium stores. We will use data from all subjects participating in HSC Protocol 2009-0055 to evaluate whether magnesium status is a co-factor in the change in calcium absorption that occurs with vitamin D therapy.

  • Assessing relationships between magnesium status and bone mineral density. [ Time Frame: 0-12 months ] [ Designated as safety issue: No ]
  • Evaluate how magnesium status impacts the relationship between vitamin D levels and parathyroid hormone levels. [ Time Frame: 0-12 months ] [ Designated as safety issue: No ]

Estimated Enrollment: 60
Study Start Date: May 2012
Estimated Study Completion Date: September 2014
Estimated Primary Completion Date: September 2014 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: High dose vitamin D
50,000 IU vitamin D3 every 15 days, with a loading dose of 50,000 IU per day for the first 15 days of an approximate 365-day treatment.
Dietary Supplement: vitamin D3
pharmaceutical grade D3
Other Name: Cholecalciferol
Active Comparator: Low dose vitamin D
800 IU vitamin D3 every day of an approximate 365-day treatment.
Dietary Supplement: vitamin D3
pharmaceutical grade D3
Other Name: Cholecalciferol
Placebo Comparator: Placebo
A pill that looks like the low/high dose vitamin D pills, but contains no vitamin D. Given to preserve the double-blind nature of the study.
Dietary Supplement: vitamin D3
pharmaceutical grade D3
Other Name: Cholecalciferol

Detailed Description:

Use of serum magnesium isotopes to measure fractional magnesium absorption Four day food diaries to assess magnesium intake Standard urine and serum chemistries for remaining labs as noted above

  Eligibility

Ages Eligible for Study:   30 Years to 75 Years
Genders Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • participants eligible for the study "Treatment of vitamin D insufficiency" are eligible for participation in the current sub-study

Exclusion Criteria:

  • identical to those covered in HSC #2009-0055
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01593501

Locations
United States, Wisconsin
University of Wisconsin-Madison Hospital, Clinical Research Unit, Osteoporosis Research Center
Madison, Wisconsin, United States, 53705
Sponsors and Collaborators
University of Wisconsin, Madison
Investigators
Principal Investigator: Karen E Hansen, M.D., M.S. University of Wisconsin-Madison, Department of Medicine, Division of Rheumatology
  More Information

Additional Information:
Publications:
Responsible Party: University of Wisconsin, Madison
ClinicalTrials.gov Identifier: NCT01593501     History of Changes
Other Study ID Numbers: HSC #2011-0547, R01AG028739-01A2
Study First Received: May 4, 2012
Last Updated: June 16, 2014
Health Authority: United States: Institutional Review Board
United States: Federal Government

Keywords provided by University of Wisconsin, Madison:
vitamin D
cholecalciferol
bone mineral density
Magnesium deficiency
Calcium metabolism disorders

Additional relevant MeSH terms:
Metabolic Diseases
Magnesium Deficiency
Calcium Metabolism Disorders
Deficiency Diseases
Malnutrition
Nutrition Disorders
Vitamins
Vitamin D
Ergocalciferols
Cholecalciferol
Micronutrients
Growth Substances
Physiological Effects of Drugs
Pharmacologic Actions
Bone Density Conservation Agents

ClinicalTrials.gov processed this record on September 30, 2014