Active clinical trials for "Vitamin D Deficiency"

The objectives of this study are 1) to assess the prevalence of vitamin D deficiency in a group of sub elite athletes and 2) to identify seasonal changes in vitamin D status and the effect that supplementation may have during the course of a year. The study is a double blinded parallel study design.

Previous studies suggested that vitamin D deficiency is highly prevalent in cirrhotic patients and is related to the degree of liver dysfunction as well as mortality. In gastrointestinal disorders, vitamin D absorption can be highly reduced. We herein aim to investigate the efficacy of oral vitamin D supplementation in cirrhotic patients with vitamin D insufficiency.

Vitamin D plays a key role in keeping normal mineral balance and maintaining bone health. There is accumulating evidence linking deficient vitamin D status with both type 1 and type 2 diabetes. The purpose of this study is to evaluate the effect of high dose vitamin D supplementation (120000 units per month)for 6 months on glucose homeostasis and glycemic control,in vitamin D deficient patients with non-optimally controlled type 2 diabetes mellitus.

Extra-renal sources of 1, 25-dihydroxyvitamin D can be increased to normal serum 1, 25-dihydroxyvitamin D levels in chronic kidney disease patients after administration of high dose 25-hydroxyvitamin D. The investigators observed that 1, 25-dihydroxyvitamin D concentrations were significantly increased after 3 months of omega-3 FA supplementation compared to baseline levels without 25-hydroxyvitamin D administration in dialysis patients. In this study, the investigators hypothesized that omega-3 FA and 25-hydroxyvitamin D supplementations may increase 1, 25-dihydroxyvitamin D concentrations much more compared to 25-hydroxyvitamin D supplementation only in hemodialysis patients with insufficient or deficient 25-hydroxyvitamin D levels.

It is hypothesised that the efficacy and safety of Vitamin D2 soft capsule to treat the Chronic Kidney Disease Mineral and Bone Disease (CKD-MBD) are equal to 1,25(OH)2 Vitamin D3 (Rocaltrol) in the patients with CKD stage 3-5.

It is well known that postmenopausal women are at risk for osteoporosis. The study hypothesis is that vitamin D deficiency (≤17.5nmol/L) is frequently associated with osteomalacia and will cause low BMD estimation in DXA scan due to insufficient bone mineralization. We assume that among these postmenopausal women, Vitamin D treatment will improve bone mineralization and will cause a rapid increase in BMD. According to the results, bisphosphonates therapy may be an unnecessary treatment. The objective of this study is to evaluate the impact of severe vitamin D deficiency and its correction on Bone Mineral Density (BMD) in postmenopausal women.

Type 2 diabetes (T2D) is an increasingly common and serious condition. Studies show that low vitamin D levels are associated with increased diabetes risk and that vitamin D may protect against diabetes by reducing chronic inflammation and improving insulin sensitivity and insulin secretion. However, no studies have been able to show that vitamin D actually reduces post-prandial blood glucose levels, the most clinically relevant marker of diabetes. Previously the investigators have shown that cheddar cheese and low-fat cheese can be fortified with high levels of vitamin D and that this cheese is at least as a effective as vitamin D supplements in raising blood vitamin D levels. The main purpose of this study is to see whether vitamin D enriched cheese can improve oral glucose tolerance (reduce blood glucose 2 hours after consuming a drink containing 75g sugar) in people who have low vitamin D levels and are at risk for developing T2D. Other aims are to determine the effect of vitamin D may on insulin sensitivity, insulin secretion, markers of inflammation, blood cholesterol levels, and safety markers such as urinary calcium excretion.

Vitamin D is essential to bone health. In Canada, it is obtained by sunlight exposure of the skin (between April and October) or by a few foods such as fatty fish, eggs or fortified milk and margarine. This study has 3 main goals which are to determine if Veteran's have enough vitamin D stored in their body, if adding a supplement of 2000 IU/d is enough to correct low vitamin D stores and, if specially formulated foods using an approved vitamin D supplement, are appropriate to maintain vitamin D stores in relation with functional and cognitive status. Initially, a 2000 IU supplement of vitamin D will be provided for 8 weeks. After this period, the participants will be randomly separated into 3 groups (Group A, B or C) for a period of 24 weeks. Group A will receive their usual menu. Group B will receive their usual menu with 1 portion of food containing 500 IU of added vitamin D. Group C will receive their usual menu with 1 portion of food containing 1000 IU of added vitamin D. Food intake will be assessed every 8 weeks and blood samples will be taken every 4 weeks to monitor change in blood concentration of vitamin D and other indicators of bone health. The investigators will document weight and height, hand grip strength, the mid-arm and mid-calf circumferences, the capacity to perform activities of daily living, the number of prescriptions and changes in health condition. The investigators will also take an X-ray the tibia and upper arm to document the amount and quality of bones in those regions. A total of 60 veterans of Ste-Anne's Hospital will participate in this study. Knowing more about vitamin D status and intake will help in confirming the required vitamin D recommendations for the elderly men living in long-term care institutions.

This study aims to answer the question whether oral vitamin D supplementation can decrease lung complications in children and adolescents with sickle cell disease. Lung complications are the leading causes of morbidity and of death in sickle cell disease. Infections and increased inflammation play important roles in the development of the lung problems in sickle cell disease. Emerging evidence shows that vitamin D helps the immune system to fight infection and to control inflammation and could potentially help prevent respiratory complications in patients with sickle cell disease. The investigators hypothesize that oral vitamin D3, 100,000 IU (2.5 mg), given once a month to a group of children and adolescents with sickle cell disease, will reduce the rate of respiratory events (infection, asthma exacerbation and acute chest syndrome) compared to the rate in a group given standard dose oral vitamin D3, 12,000 IU (0.3 mg) given once a month. Funding Source - U.S. Food & Drug Administration, Office of Orphan Products Development

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.