How Does Magnesium Status Influence Calcium Homeostasis?
试验速览
- 阶段
- 4 期
- 状态
- 已完成
- 入组人数
- 39
- 试验地点
- 1
- 主要终点
- Evaluate the associations between magnesium intake, magnesium stores, fractional magnesium absorption and calcium homeostasis.
研究概览
简要总结
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.
详细描述
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
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Double (Participant, Investigator)
入排标准
- 年龄范围
- 30 Years 至 75 Years（Adult, Older Adult）
- 性别
- Female
- 接受健康志愿者
- 是
入选标准
- •participants eligible for the study "Treatment of vitamin D insufficiency" are eligible for participation in the current sub-study
排除标准
- •identical to those covered in HSC #2009-0055
研究组 & 干预措施
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.
干预措施: vitamin D3 (Dietary Supplement)
Low dose vitamin D
800 IU vitamin D3 every day of an approximate 365-day treatment.
干预措施: vitamin D3 (Dietary Supplement)
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.
干预措施: vitamin D3 (Dietary Supplement)
结局指标
主要结局
Evaluate the associations between magnesium intake, magnesium stores, fractional magnesium absorption and calcium homeostasis.
时间窗: 0-12 months
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.
次要结局
- Assessing relationships between magnesium status and bone mineral density.(0-12 months)
- Evaluate how magnesium status impacts the relationship between vitamin D levels and parathyroid hormone levels.(0-12 months)
- Does vitamin D therapy have a differential impact on calcium absorption that is dependent on magnesium stores?(0-12 months)