The Effect of Vitamin D Supplementation on Markers for Cardiovascular Disease and Diabetes: an Individual Participant Data Meta-analysis of Randomized Controlled Trials
试验速览
- 阶段
- 不适用
- 发起方
- 入组人数
- 2,945
- 主要终点
- HbA1c
研究概览
简要总结
This meta-analysis will be conducted to study the effect on vitamin D supplements on markers for cardiovascular disease and diabetes using individual participant data from 12 RCTs. Given that previous data suggest that vitamin D supplementation might be most effective in those individuals with very low 25-hydroxyvitamin D (25(OH)D) and potentially harmful in those achieving very high levels after vitamin D supplementation, this meta-analyses will be performed in subgroups according 25(OH)D levels.
详细描述
Large randomized controlled trials (RCTs) are currently on-going to evaluate non-skeletal effects of vitamin D supplementation in the general older population. The results of these studies can be expected in 2017 to 2020 and while they will report important data, they may still leave knowledge gaps on the effects of vitamin D on clinically relevant surrogate parameters in specific groups. Recent data indicate that the association of vitamin D status and outcome is U- or reverse J-shaped and may be modified by the presence of certain risk factors or genetic variations of the vitamin D receptor.
This work is part of the European Union-project 'Food-based solutions for eradication of vitamin D deficiency and health promotion throughout the life cycle' (ODIN). This individual patient meta-analysis of existing high quality vitamin D RCTs aims to evaluate whether there are beneficial or harmful vitamin D effects on surrogate parameters for clinical outcomes (i.e. blood pressure, lipids, parathyroid hormone (PTH), fasting blood glucose and glycated haemoglobin (HbA1c)). With data from almost 3000 randomized subjects from 12 RCTs that are available within this consortium, the investigators will have sufficient power to detect clinically relevant effects of vitamin D supplementation on risk factors for cardiovascular disease.
Subgroup analyses will investigate effect modifiers to evaluate whether certain groups of individuals experience pronounced or attenuated effects from vitamin D supplementation. Given that previous data suggest that vitamin D supplementation might be most effective in those individuals with very low 25(OH)D and potentially harmful in those achieving very high levels after vitamin D supplementation, this individual patient data meta-analyses will be performed in subgroups with serum 25(OH)D levels <30, 40, and 50 nmol/L and >100, 125 and 150 nmol/L. 25(OH)D levels will be re-measured to ensure comparability.
研究设计
- 研究类型
- Observational
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Availability of quality bio-banked samples for uniform 25(OH)D re-measurement
- •Prospective data on one or more of the outcomes
- •Willingness to collaborate
排除标准
- •Trials among pregnant women, children, or performed in patient populations.
结局指标
主要结局
HbA1c
时间窗: Participants were followed for the duration of the intervention period (range 8 weeks - 1 year, depending on the RCT in which they are participating)
(Main outcome of diabetic markers)
Blood pressure
时间窗: Participants were followed for the duration of the intervention period (range 8 weeks - 1 year, depending on the RCT in which they are participating)
Systolic and diastolic (Main outcome of cardiovascular markers)
次要结局
- High-density lipoproteins (HDL) cholesterol(Participants were followed for the duration of the intervention period (range 8 weeks - 1 year, depending on the RCT in which they are participating))
- Fasting glucose(Participants were followed for the duration of the intervention period (range 8 weeks - 1 year, depending on the RCT in which they are participating))
- Triglycerides(Participants were followed for the duration of the intervention period (range 8 weeks - 1 year, depending on the RCT in which they are participating))
- C-peptide(Participants were followed for the duration of the intervention period (range 8 weeks - 1 year, depending on the RCT in which they are participating))
- Two-hour glucose(Participants were followed for the duration of the intervention period (range 8 weeks - 1 year, depending on the RCT in which they are participating))
- Low-density lipoproteins (LDL) cholesterol(Participants were followed for the duration of the intervention period (range 8 weeks - 1 year, depending on the RCT in which they are participating))
- Total cholesterol(Participants were followed for the duration of the intervention period (range 8 weeks - 1 year, depending on the RCT in which they are participating))
- Parathyroid hormone (PTH)(Participants were followed for the duration of the intervention period (range 8 weeks - 1 year, depending on the RCT in which they are participating))
- Fasting insulin(Participants were followed for the duration of the intervention period (range 8 weeks - 1 year, depending on the RCT in which they are participating))
研究者
Karin Swart
PhD
Amsterdam UMC, location VUmc