Vitamin D Deficiency clinical trials at UC Health
4 in progress, 2 open to eligible people
open to eligible people ages 18 years and up
The purpose of this study is to compare the effects of two different forms of vitamin D supplements (vitamin D3 and 25-hyrdroxyvitamin D3 [25(OH)D3]) on vitamin D levels in the blood, and on markers of skeletal and immune health. This study is designed as a pilot study. A multi-ethnic cohort of 48 patients will be included (12 Caucasian, 12 African American, 12 Hispanic/Latino, 12 Asian/Asian American). Potential study candidates will undergo a screening visit during which a medical history will be taken, a physical exam performed, a dietary questionnaire administered, and blood collected. The purpose of the screening visit is to identify vitamin D-deficient (25-hydroxyvitamin D <20 ng/ml) individuals who are candidates for vitamin D supplementation. Eligible patients will then be randomly assigned to receive either vitamin D3 (2400 IU/day) or 25(OH)D3 (20 mcg/day) for 16 weeks. After initiating supplementation, study patients will return for follow-up visits at weeks 4, 8, and 16. At each visit, blood will be collected to assess vitamin D levels in the blood, as well as markers of skeletal and immune function. Participation in this study will therefore involve a total of 5 visits (1 screening visit, 1 randomization visit during which participants will receive their study supplements, 3 follow-up visits). After all data is collected, changes in vitamin D levels in the blood following supplementation with either vitamin D3 versus 25(OH)D3 will be determined, and correlated to markers of calcium balance and immune function. Knowledge gained from this study may have a significant impact on how vitamin D status is defined, and how vitamin D repletion is administered.
open to eligible females ages 18-45
Open-label randomized clinical trial assessing the efficacy of Metformin versus Vitamin D in improving symptoms of depressed mood in polycystic ovary syndrome.
“This study will test if supplementing high dose vitamin D will correct severely low vitamin D levels in adults 65-90 years old.”
Sorry, not yet accepting patients
This Phase II randomized clinical trial aims to test if supplementation with high dose oral vitamin D will successfully correct vitamin D insufficiency, compared to treatment with standard (RDA) dose vitamin D in a diverse community-based elderly cohort. The effect of high-dose vs. standard-dose vitamin D on altering cognitive trajectories will also be assessed and data will be expected to be used in designing a potential definitive Phase III trial in elderly groups at risk for dementia. A total of 180 elderly persons with longitudinal biomarkers, neuropsychological testing and brain MRI scans will be enrolled, with 152 (~50 with MCI, 50 with mild AD and 50 with no cognitive impairment) expected to complete the 3½-year study. One-half of each diagnostic group will be randomized to treatment with high-dose vitamin D3 (4,000 IU daily) or to standard dose Vitamin D (600 IU capsule daily + ~200 IU dietary = ~800 IU total/day). Longitudinal MRI analyses will provide an estimate of the treatment effect size on brain atrophy rate. Vitamin D receptor genotype polymorphisms and their impact on response to oral supplementation will also be examined. If vitamin D supplementation improves cognitive outcome, this could have a large impact on the public health, since low vitamin D status is a common, readably treatable condition which may provide a novel window to prevent dementia and AD. Furthermore, the higher prevalence of AD and dementia in African Americans and Latinos could be partially attributable to vitamin D insufficiency.
at UC Davis
Sorry, currently not accepting new patients, but might later
We would like to determine if vitamin D insufficiency exists in different ethnic groups, if it has an effect on bone mass and muscle function, if it has an impact on the function of the cells of the immune system, and if the functioning level of these systems can be improved by stabilizing the vitamin D levels to within normal limits.