Active clinical trials for "Vitamin D Deficiency"

Total 25(OH)D is currently used as a biomarker of vitamin D status. However, there is some debate as to whether total 25(OH)D is the best marker to use. It has been suggested that free vitamin D may be better because it may be more biologically available. There are also some uncertainties about how we treat vitamin D deficiency. A single dose is attractive because it is certain that the patient has had the dose and there is no requirement for ongoing compliance, but it is still not clear what the best dose is to give. Also, recent studies have highlighted that high dose vitamin D supplementation may increase the risk of falling in older populations. The investigators believe that studying how free vitamin D responds to different bolus doses is the best way address some of the current research gaps, including what is the best biomarker of vitamin D status, what is the mechanism of vitamin D toxicity and what is a safe bolus dose to treat deficiency. The investigators will study changes in total and free 25(OH)D, and also clinical response, to three different bolus doses of vitamin D (50 000IU, 150 000IU and 500 000IU) in 84 vitamin D deficient postmenopausal women, over a three month period with 5 study visits. A concurrent control group of 28 vitamin D sufficient postmenopausal women will also be recruited. This will allow the investigators to determine how total and free vitamin D change with bolus dosing and whether there is a disproportionate rise in free 25(OH)D with higher doses that may lead to hypercalcemia and falls.

There is a high prevalence of vitamin D deficiency in Switzerland. In indoor-athletes as well as wheelchair users, vitamin D deficiency occurs even more often. It is well established that vitamin D deficiency has a negative effect on health. However, vitamin D supplementation in individuals with a vitamin D deficiency has a positive effect on muscle performance. In recently published studies with able-bodied subjects, it has been shown that a normal vitamin D level (>75nmol/L) can only be achieved with a high-dose supplementation of vitamin D. The aim of this study is to examine the effect of vitamin D supplementation on exercise performance in wheelchair athletes with vitamin D deficiency . All participants with a vitamin D deficiency are assigned to the intervention group and treated with 6000 IU of vitamin D3 daily over a period of 12 weeks. All participants who have a normal vitamin D level will receive placebo treatment (control group). The physical performance is measured three times at baseline, after six weeks and 12 weeks. The measurements include a Wingate and a dynamometer test.

The purpose of this study is to see whether giving a Vitamin D supplement to vitamin D deficient obese children and adolescents will decrease the risk of getting diabetes (Disease in which the person has high blood sugar). The number of vitamin D deficiency in U.S. children and teenagers has grown dramatically over the past 30 years. There are some reports suggesting that vitamin D supplementation in adults with pre diabetes (blood glucose higher than normal) and vitamin D treatment will prevent diabetes.

To test the hypothesis that vitamin D treatment during 12 weeks to palliative cancer patients can decrease opioid consumption, fatigue and infectious burden and increase quality of life.

Screening the prevalence of vitamin D deficiency among Egyptian hemodialysis patients on a single center (Ain Shams University hospital). Assessing the effect of the native type of vitamin D (Cholecalciferol) on replenishing its deficiency via extra-renal vitamin D receptors (VDR), among Egyptian hemodialysis patients. Assessing the effect of cholecalciferol on vascular calcification among Egyptian hemodialysis patients. Assessing the effect of cholecalciferol on Blood pressure, parathyroid hormone.

The study evaluates the effect of oral vitamin D supplementation on the severity of psoriasis measured by Psoriasis Area Severity Index (PASI) in adults with lower vitamin D levels. Half of the participants will receive vitamin D, while the other half receive placebo.

The main objective of this study is to find a correlation between vitamin D deficiency and stress fracture occurrences in athletes who participate in high-risk activities. These high-risk athletes undergo elevated bone turnover, which requires adequate levels of vitamin D in order to support bone health. It is hypothesized that providing supplemental treatment to athletes showing lower than normal serum vitamin D levels will decrease the occurrence of stress fractures. By recording the dates and specific occurrences of fractures, it may be possible to correlate injury rates with seasons, providing more supportive data to pre-existing literature. This area of research is lacking in the quantity of prospective studies. Previous studies primarily focus on adolescent, elder, or military recruit populations. While literature has shown that vitamin D plays an important role in bone health, there are no previous studies that directly examine vitamin D deficiency and supplemental treatment in conditioned collegiate athlete populations. This study will add to the existing knowledge and will provide a more specific analysis for athletes.

Two-thirds of the US population, particularly African Americans (AA), is at risk for inadequate or deficient 25-hydroxy-vitamin D (25(OH)VD). Epidemiological studies demonstrate an association between better health outcomes and higher blood levels of 25(OH)VD . Randomized controlled clinical trials have shown that, while supraphysiological high doses of VD are needed to achieve adequate blood levels of 25(OH)VD, not all subjects respond to them. Recent studies have also questioned the therapeutic effects of high-dose VD supplementation. Severe VD deficiency has been associated independently with the future risk of mild cognitive impairment (MCI) and dementia. A reduction in GSH and an increase in the oxidative stress levels of serum, erythrocytes, and circulating lymphocytes has been observed in MCI and Alzheimer disease, findings similar to those in VD deficient persons. Scholarly reviews conclude that excess oxidative stress is one of the major risk factors for AD and support a potential therapeutic role for L-cysteine (LC, a GSH precursor) and vitamin D (VD) supplementation in the treatment of Alzheimer disease symptoms. This application presents the investigators' design for a randomized, double-blind, placebo-controlled clinical trial to test the hypothesis that supplementation with VD in combination with L-cysteine (LC) is more successful at optimizing the statuses of 25(OH)VD [biological signatures] and simultaneously decreasing TNF-α, IR [functional or clinical outcomes], and oxidative stress, suggesting a better therapeutic approach compared with supplementation with VD alone in AA subjects.

Children with Down's syndrome (DS) are more liable to vitamin D deficiency. Treating this deficiency with supplements is associated with the risk of intoxication due to increased intestinal absorption or decreased vitamin D metabolism. The aim of the study was to compare the effect of two exercise intensities on the modulation of vitamin D and Parathormone (PTH) levels in children with DS.

Hypovitaminosis D is common in the adult population, it affects at least 1 billion people worldwide, and in particular 80% of the French population according to the National Institute for Public Health Surveillance. Hypovitaminosis D is accompanied or complicated by deleterious health manifestations such as bone, immune and cancer diseases, neuromuscular disorders and a propensity to fall, for example. Hypovitaminosis D has also been associated with more complicated care pathways (increase in the severity of the reason for hospitalization, length of hospitalization, risk of in-hospital death). Prevention of these clinical events depends on correcting vitamin D status. In sick, dependent or fragile adults, natural intakes are generally insufficient. It is indeed accepted that hypovitaminosis D may not be treated effectively by dietary measures or by simple exposure to the sun in French latitudes. Drug supplementation is therefore necessary, with the objective of achieving a target concentration of circulating 25-hydroxyvitamin D (25 (OH) D) of 75 nmol / L (30 ng / mL) in this population. Vitamin D supplementation, when properly conducted, corrects hypovitaminosis D, and has been associated with improved prognosis, especially life-saving, in therapeutic trials versus placebo. Such results lead the investigators to suggest that the identification and correction of hypovitaminosis D in hospitalized patients could represent a simple, effective and inexpensive strategy for improving hospital care pathways. In this perspective, the first step is to determine the prevalence, severity and clinical profile of hospitalized patients with hypovitaminosis D, as well as their course of care. To the investigators knowledge, there are no large-scale studies based on real-life data on this subject.