Vitamin D Supplementation, Upper Respiratory Tract Infections, Immune and Physical Functions in Adolescent Swimmers
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 82
- 试验地点
- 4
- 主要终点
- URI frequency
研究概览
简要总结
Background: The medical and economic burden of upper respiratory tract infections (URTIs) is extremely high, while prevention and treatment options are limited. Therefore, there is a constant need for new methods in order to significantly decrease such morbidity. Extensive evidence shows that vitamin D is associated with respiratory health, including in the prevention and treatment of URTIs. Competitive swimmers have a high prevalence of URTIs, and can serve as a model for research in this field.
The study hypothesis is that vitamin D supplementation to young swimmers with low vitamin D levels will reduce the frequency, length, and severity of URTIs and their accompanying functional impairment, while improving cellular immune function and physical function.
Methods: After screening 100 competitive adolescent swimmers to obtain ~60 with low serum levels of vitamin D, this study group will be randomized to receive either vitamin D supplementation (2000 IU/d) or placebo, given in a double blinded fashion for three months. Participants will fill a daily questionnaire regarding frequency, length and severity of URTIs symptoms and functional impairment. Blood will be drawn to evaluate changes in vitamin D status (25(OH)D) and immune function among study participants at the beginning of the study and after supplementation. Physical function on land and in water will also be assessed.
Expected results: Increase in serum 25(OH)D levels following supplementation will significantly decrease the frequency, length and severity of URTI's and their functional impairment, while enhancing the cellular immune system function and physical capacity.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Prevention
- 盲法
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 12 Years 至 18 Years（Child, Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •members of swimming team
- •training at least 15 hours/week
- •low vitamin D plasma levels (<30 ng/ml)
- •signed consent forms
排除标准
- •chronic health conditions
- •taking prescription medications
- •taking diet supplementations
结局指标
主要结局
URI frequency
时间窗: 3 months
URI frequency will be measured in both groups, starting 4 weeks after initiating the suplementation. Analysis will also assess differences by sex or initial vitamin D levels, as well as by immune function changes.
URI duration
时间窗: 3 months
URI duration will be measured in both groups, starting 4 weeks after initiating the suplementation. Analysis will also assess differences by sex or initial vitamin D levels, as well as by immune function changes.
UTI severity
时间窗: 3 months
URI severity will be measured in both groups, starting 4 weeks after initiating the suplementation. Analysis will also assess differences by sex or initial vitamin D levels, as well as by immune function changes.
次要结局
- plasma vitamin D levels(3 months)
- immune system function(3 months)
- physical function(3 months)
研究者
Gal Raz-Dubnov MD, MSc
senior physician
Sheba Medical Center