Vitamin D Deficiency
Conditions
Keywords
Hypovitaminosis D, Free 25-hydroxyvitamin D, Total 25-hydroxyvitamin D
Brief summary
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.
Interventions
DRUGVitamin D
2400 IU/day by mouth for 16 weeks
DRUG25(OH)D3
20 micrograms/day by mouth for 16 weeks
Sponsors
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
University of California, Los Angeles
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Age \> 18 * 25D \< 20 mg/ml
Exclusion criteria
* Age \< 18 * 25D \> 20 ng/ml at time of screening * Clear signs of infection at time of screening (coughing, sneezing, wheezing, frequency, dysuria) * History of conditions that would influence intestinal absorption of vitamin D3 or 25OHD3 supplements * History of nephrolithiasis, primary hyperparathyroidism, or other metabolic bone disease * History of chronic kidney disease (defined as CrCl \< 30 ml/min) * History of rheumatologic or autoimmune conditions * History of sarcoidosis * History of active or latent tuberculosis * History of HIV * History of hyperthyroidism * History of chronic glucocorticoid use defined as the equivalent of 5 mg of prednisone per day for more than 2 months within the last 6 months * History of use of medications known to affect calcium/vitamin D metabolism, bone metabolism, and immune response * Hypercalcemia * Hypercalcinuria
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Change in total serum 25D | 16 weeks |
Secondary
| Measure | Time frame |
|---|---|
| Change in serum total 1,25D | 16 weeks |
| Change in total free 1,25D | 16 weeks |
| Change in serum calcium | 16 weeks |
| Change in serum free 25D | 16 weeks |
| Change in serum iPTH | 16 weeks |
| Change in serum bone turnover markers | 16 weeks |
| Change in markers of immune function | 16 weeks |
| Change in urinary calcium | 16 weeks |
Countries
United States
Outcome results
None listed