Effect of Vitamin D Supplementation on Endothelial Function in Obese Adolescents
试验速览
- 阶段
- 1 期
- 状态
- 已完成
- 发起方
- Mayo Clinic
- 入组人数
- 19
- 试验地点
- 2
- 主要终点
- Flow Mediated Dilatation (FMD)
研究概览
简要总结
Vitamin D deficiency has been linked to endothelial dysfunction in adults. Obese adolescents have a high prevalence of Vitamin D deficiency as well as evidence of endothelial dysfunction. Our hypothesis is that supplementation of Vitamin D deficient adolescents with Vitamin D would lead to improvement in endothelial dysfunction.
详细描述
Subjects had a brief screening visit with one of the study team members. Past medical history, current medications and a brief dietary history was taken. The dietary history was taken to assess calcium intake in a day and was obtained via the validated Short Calcium questionnaire. Blood pressure, heart rate as well as height,weight, waist and hip circumference measurement was obtained by study staff. In addition, a brief physical examination to determine Tanner stage was also completed. This involved examination of both breasts and genitalia for adolescent female and only genitalia in males. A physical activity questionnaire (IPAQ) was also administered by the study staff at this visit. A blood draw of 5 ml to measure plasma 25(OH) D, calcium, phosphorus was obtained as part of the screening visit. For girls who had started menstruating, a urine pregnancy test was also obtained.
After the screening visit eligible subjects had baseline biochemical tests and an endothelial function assessment. Study participants received a pill container with six total pills of vitamin cholecalciferol (D3) (1 pill = 50,000 IU), with directions to take two pills once a month (100,000 IU) at the same time for a period of 3 months. Compliance was assessed at the 3 month visit by counting the number of pills remaining in the container.
At 1 month, the subjects had tests for serum calcium and 25 hydroxy vitamin D levels. A urine test for random calcium to creatinine ratio was also obtained.
At 2 months, the serum calcium, 25 hydroxy vitamin D levels, and calcium to creatinine ratio tests were repeated.
At the end of 3 months, biochemical tests and an endothelial function assessment were repeated. Medical history, questionnaires, and the physical exam were also repeated.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Prevention
- 盲法
- None
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
- •Age 12-18 years
- •BMI >95% for age and gender
- •25 (OH) D levels less than 30 ng/ml
排除标准
- •25 (OH) D levels >30 ng/mL
- •Serum calcium >10.4 mg/dL
- •Serum phosphorus > 4.7 mg/dl
- •Pregnancy or nursing
- •Current cancer
- •Patients on vitamin D3 supplementation exceeding 400 IU/day
- •Hypertension defined as Blood Pressure over the 95th percentile for age, gender and height
- •Dietary calcium intake exceeding 1500 mg/day
- •Hepatic or renal disorders
- •Type 1 or type 2 diabetes mellitus
- •Subjects receiving insulin, metformin, or oral hypoglycemic medications
- •Subjects with malabsorption disorders (celiac disease, cystic fibrosis, inflammatory bowel disease)
结局指标
主要结局
Flow Mediated Dilatation (FMD)
时间窗: baseline, 3 months
Endothelial function was assessed by FMD, via a high-resolution Doppler ultrasonography examination of the right brachial artery. FMD was calculated as the maximal percentage increase in brachial artery diameter (BAD) from baseline after the release of cuff occlusion.
次要结局
- Triglycerides(baseline, 3 months)
- Serum Parathyroid Hormone (PTH)(baseline, 3 months)
- Body Mass Index(baseline, 3 months)
- Total Cholesterol(baseline, 3 months)
- Calcium Intake Per Day(baseline, 3 months)
- Homeostatic Model Assessment of Insulin Resistance Index (HOMA-IR)(baseline, 3 months)
- High Sensitivity C-reactive Protein (Hs-CRP)(baseline, 3 months)
- Reactive Hyperemia Index (RHI)(baseline, 3 months)
- 25-hydroxy Vitamin D (25[OH]D) Levels(baseline, 3 months)
- International Physical Activity Questionnaire (IPAQ) Short Form Score(baseline, 3 months)
- Fasting Insulin(baseline, 3 months)
- Low-density Lipoprotein Cholesterol (LDL) Cholesterol Levels(baseline, 3 months)
- Fasting Glucose(baseline, 3 months)
- Urine Calcium to Creatinine Ratio(baseline, 3 months)
- High Density Lipoprotein (HDL) Cholesterol Levels(baseline, 3 months)