Determining the Effects of Race, Skin Colour and Genotype on the Response to Vitamin D Therapy
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 60
- 试验地点
- 2
- 主要终点
- Increase in serum 25 hydroxyvitaminD (25OHD) levels
研究概览
简要总结
The investigators want to make sure that people get the right dose of Vitamin D treatment. They will therefore investigate how skin colour, body mass index, ethnicity, vitamin D binding protein and genetic variation affect the response to a standard course of vitamin D in young adults, as a prelude to further studies in younger children.
详细描述
The Department of Health and the Chief Medical Officer have identified vitamin D deficiency as a key area of interest and concern for public health.
The main function of vitamin D is to enable dietary calcium to be absorbed from the intestine. Low levels of vitamin D can lead to diseases of bone such as rickets and osteomalacia and are linked to a higher risk of fracturing bones in older women with osteoporosis.
Vitamin D levels may be affected by the skin colour, body mass index (BMI), lifestyle or environment in which someone lives, and by their genetic makeup. Vitamin D levels tend to be lower in people with higher BMI and / or darker coloured skin or if the skin is covered by clothing because a lot of vitamin D is made from the action of sunlight on natural chemicals in the skin.
Vitamin D does occur naturally in the diet in foods like oily fish, and also vitamin D can be given as a supplement either on its own or as part of a multivitamin tablet.
There is natural variation from one person to another in how well the system controlling vitamin D blood levels works. Vitamin D circulates bound to a carrier protein, vitamin D binding protein (VDBP). When vitamin D levels are measured, both vitamin D bound to the protein and "free" vitamin D are measured.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Diagnostic
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 25 Years（Adult）
- 性别
- Male
- 接受健康志愿者
- 是
入选标准
- •Healthy young male adults aged 18 25 years
- •Free from any condition affecting bone health, general nutrition, growth and glucose metabolism.
排除标准
- •Subjects with any chronic illness involving the liver and kidney
- •Use of steroids, anticonvulsants or any medication that might affect calcium and vitamin D metabolism.
- •Potential participants who have made plans to travel abroad during the study period.
结局指标
主要结局
Increase in serum 25 hydroxyvitaminD (25OHD) levels
时间窗: Participants will be followed for the duration of the study, an expected average of 4 weeks
Increase in serum 25OHD levels by at least 25 nmol/L in the majority of the participants, 4 weeks after administration of 150,000 units of vitamin D, according to genotype and ethnicity.
次要结局
- Determine if dark skin colour or South Asian heritage reduces the increase in serum 25OHD.(Participants will be followed for the duration of the study, an expected average of 4 weeks)
- Change in serum calculated free vitamin D(Participants will be followed for the duration of the study, an expected average of 4 weeks)
- Determine if variation in Group specific component(GC) genotype is associated with variation in the increase in serum 25OHD.(Participants will be followed for the duration of the study, an expected average of 4 weeks)
- Determine the extent of parathyroid hormone (PTH) suppression in relation to overall increases in total and free serum 25OHD(Participants will be followed for the duration of the study, an expected average of 4 weeks)