View clinical trials related to Vitamin D Deficiency.
Filter by:Research Title: The effect of vitamin D replacement on airway reactivity, allergy and inflammatory mediators in exhaled breath condensate in vitamin D deficient asthmatic children. Introduction: Vitamin D seems to play a role in allergic and asthmatic reactions as an immunomodulator. Asthma disease involves inflammatory process in the lower respiratory tract and airway hyperreactivity. Aim: To assess the effect of Vitamin D replacement on airway reactivity, and allergy and inflammatory mediators in exhaled breath condensate in vitamin D deficient asthmatic children. Design: Double blind placebo control prospective study comparing the effect of Vitamin D replacement and placebo on airway reactivity, allergy and inflammatory mediators in exhaled breath condensate in asthmatic pediatric population with vitamin D deficiency. Participant selection: The study group will consist of pediatric patients (age 6-18 years) followed and treated at the Pediatric Pulmonary Unit at the investigators hospital. Patients with mild-moderate asthma with low or insufficient vitamin D levels that are currently not receiving anti-inflammatory treatment will be recruited. Sample size: 60 participants in the two groups (30 receiving Vitamin D and 30 receiving placebo). Intervention: Vitamin D (14000 units) or placebo will be provided in a similar appearance preparation once weekly for 6 weeks between visit two and three. Three visits will be conducted. Each subject will undergo evaluation including a respiratory questionnaire (visit 1), methacholine challenge test with determination of PC20 (visit 1 or 2 and visit 3), exhaled nitric oxide (eNO) (visit 2, 3), and exhaled breath condensate (EBC) (visit 2,3). Venous blood will be analyzed for complete blood count + eosinophils (visit 1, 3), IGE levels (visit 1, 3), and Vitamin D levels (visit 1, 3). Prick skin test for inhaled allergens will be performed (visit 2, 3). Primary end point: Airway reactivity as assessed by methacholine challenge test. Secondary outcome parameters: All other parameters are the secondary end points.
This study seeks to determine if vitamin D3 absorption in healthy adults will be enhanced in the presence of a meal and if the enhancement will be greater when the meal is low as opposed to high in fat content. The enhancement will result from increased vitamin D absorption. The investigators will test this hypothesis by pursuing the following aims in a 3-mo trial in which up to 70 healthy men and women will be randomized to one of the following meal conditions under which they will take a monthly oral dose of 50,000 IU of vitamin D3: no meal (fasting), a low fat meal, or a high fat meal. The Primary Aim is to identify the meal condition (fasting, low-fat, or high-fat meal) under which the 25OHD3 response to supplemental vitamin D3 is greatest and most consistent. The Secondary Aim is to determine whether vitamin D3 absorption is affected by the meal condition and to determine whether the absorption of vitamin D3 predicts the longer-term 25OHD3 response to supplementation.
Healthy subjects with low Vitamin D levels will be randomly assigned to either Vitamin D replacement or placebo for a period of 8 weeks. Insulin sensitivity will be measured before and after the intervention, and the changes will be compared between the two groups. This will help us understand if Vitamin D replacement improves insulin sensitivity. Serum Retinol Binding Protein 4 levels will also be measured to see if changes in insulin sensitivity are mediated by RBP4.
This is a research study to look at vitamin D deficiency (low levels) in men and women with HIV. As part of your regular medical care, you will be screened for vitamin D deficiency. If your levels are low, and you choose to start using vitamin D supplements, the investigators would like to take some blood before and after you start using vitamin D to see how this affects your levels of HIV, T cells, cholesterol, and other blood levels. The investigators will provide you with vitamin D supplements for the first 24 weeks (6 months) of the study. If you and your physician decide that you should continue taking vitamin D supplements after that time, you will be responsible for purchasing your own vitamin D supplements.
The investigators proposed a pilot study preparatory to developing a randomized trial of vitamin D for the prevention of TB infection. The specific aims are presented below: 1. To recruit subjects, obtain consent, distribute vitamin D supplements to the children in the schools, obtain blood samples and transport them to the United States. 2. To test the hypothesis that daily vitamin D supplementation will increase plasma levels of 25(OH)D, and restore TLR-induced antimicrobial activity in monocytes/macrophages tested in vitro.
This is a randomized, double-blind, multicenter, 6-month follow-up trial of low (400 IU/day) versus high (4000 IU/day) dose vitamin D supplementation in individuals with pre- and early stage 1 hypertension and vitamin D deficiency. A total of 530 participants (265 participants per treatment arm) will be randomized between 3 sites. Approximately 2,250 participants will be screened between the 3 sites. Vital signs, 24-hour ambulatory blood pressure monitoring, clinical laboratory safety tests and adverse event assessments will be performed to evaluate the effectiveness of the two doses of vitamin D on blood pressure. Blood samples will be stored for future biomarker assessments. The total duration of the study is anticipated to be 18 months, assuming a 12 month enrollment period.
Adequate vitamin D is essential for proper infant growth and development. However, human milk is low in vitamin D, and most infants do not receive recommended supplementation. Our aim is to assess the feasibility of providing adequate vitamin D to breastfed infants through maternal vitamin D supplementation. Forty non-pregnant, lactating women at least 18 years of age with exclusively breastfed infants between the ages of 1 and 6 months will be randomized to receive oral vitamin D as either 5,000 IU daily for 28 days or 150,000 IU as a single dose. Maternal serum calcium, phosphorus, vitamin D and 25(OH)D; maternal urinary calcium; maternal milk vitamin D and 25(OH)D will be measured on days 0, 1, 3, 7, 14, and 28 of the study; and infant serum vitamin D and 25(OH)D will be measured on days 0 and 28.
Experimental and human data suggests that vitamin D could protect against breast cancer. Overweight/obese individuals are at increased risk of low vitamin D levels. Vitamin D may reduce production of fat tissue, thereby reducing weight gain, which would result in lower levels of adipose-derived hormones and other breast cancer risk factors.The purpose of this study is to test the effect of vitamin D supplementation on the response to a weight loss (diet + exercise) intervention and select breast cancer risk factors in overweight and obese postmenopausal women with low blood vitamin D levels.
This is a double-blind placebo controlled pilot study to determine if vitamin D supplementation in hemodialysis (HD) patients will improve physical function and cognition. HD patients have a high prevalence of vitamin D deficiency, cognitive impairment, and physical impairment. Despite standard clinical care with active IV vitamin D during dialysis, HD patients still have markedly low levels of nutritional or dietary vitamin D. IV treatment with vitamin D during dialysis is aimed at treating HD related bone disease. Recent literature shows that oral or nutritional vitamin D has multiple extra-skeletal effects including improvement in cognition and physical function. In this study, the investigators plan to administer oral vitamin D to vitamin D deficient HD patients already receiving standard care with IV vitamin D therapy. Patients will be randomized to receive either placebo or 50,000 IU of vitamin D (cholecalciferol) weekly for 6 months. The investigators' specific aims are to 1) Assess the benefits of correcting nutritional vitamin D deficiency on cognitive and physical function in HD patients receiving routine standard of care, 2) Assess the feasibility of recruiting HD patients for this study, and 3) Evaluate the proposed regimen for safely and effectively increasing nutritional vitamin D levels with oral supplementation. The investigators anticipate that correction of nutritional vitamin D deficiency to optimal levels will improve the high prevalence of cognitive impairment and physical impairment in this population. These results will be used as evidence to support a larger study aimed at treating nutritional vitamin D deficiency in all patients receiving HD. These results may also contribute to a change in current guidelines which place little emphasis on the monitoring and treatment of nutritional vitamin D levels in HD patients. These results are important for the Veteran dialysis population since many of them are required to perform high-level cognitive tasks such as management of complex medical regimens and physical tasks such as orchestrating independent transportation to and from HD sessions and multiple physician appointments.
Vitamin D deficiency is wide spread in South Asian population and is contributing to burden of disease in this region including Pakistan. The relative importance of vitamin D deficiency, mutation in its receptor and maternal and child health has not been established in Pakistan and population based studies are required to explore and avert the maternal and Neonatal complications and consequences of Vitamin D deficiency The trial will evaluate the effectiveness of Vitamin D supplementation to pregnant women and their Infants. It will be a double blind placebo controlled trial, which will be conducted in a rural district of Pakistan.