Personalized Vitamin D Supplementation in European and African Americans
3 other identifiers
interventional
169
1 country
2
Brief Summary
The proposed study is a randomized, double-blind, controlled, multi-center clinical trial of six months of daily oral vitamin D3 (cholecalciferol). This study will randomize 334 community-dwelling post-menopausal women of European and African descent (\~167 from each ancestry) in a 1:1 ratio between the control arm and the dosing algorithm arm using stratified block randomization with a block size of six and stratification by site (ancestry). The sample size of 334 includes 10% over-recruitment to allow for loss to follow-up. The European ancestry women will be seen in the Madison clinic and the African ancestry women will be seen in the Milwaukee clinic. The proposed study will focus on post-menopausal women because this is the subset of the population that both Dr. Engelman's and Dr. Binkley's preliminary data are drawn from. Moreover, 25(OH)D concentrations are typically lower in women and in older individuals, since production of vitamin D in the skin following sun exposure decreases with age. Therefore, this group of individuals is likely to benefit the most from vitamin D supplementation, especially when personalized based on biology using the proposed dosing algorithm.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for not_applicable
Started Oct 2015
Longer than P75 for not_applicable
2 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
January 22, 2015
CompletedFirst Posted
Study publicly available on registry
February 12, 2015
CompletedStudy Start
First participant enrolled
October 30, 2015
CompletedPrimary Completion
Last participant's last visit for primary outcome
May 3, 2019
CompletedStudy Completion
Last participant's last visit for all outcomes
May 3, 2019
CompletedResults Posted
Study results publicly available
November 13, 2020
CompletedDecember 1, 2020
November 1, 2020
3.5 years
January 22, 2015
October 21, 2020
November 13, 2020
Conditions
Outcome Measures
Primary Outcomes (1)
Efficacy of the Dosing Algorithm in Achieving Total 25(OH)D as Measured by the Percentage of Participants Ending With Concentrations of 35-50 ng/mL
To validate the proposed vitamin D3 dosing algorithm, a vitamin D panel consisting of serum concentrations of vitamin D3 (cholecalciferol; an indicator of vitamin D3 absorption), 25(OH)D3, 25(OH)D2, the C3-epimer of 25(OH)D3 and 24,25(OH)2D as well as an assay to directly measure free serum 25(OH)D will be run on all the blood samples collected at the baseline, 3 month and 6 month visits.
3 and 6 months
Study Arms (2)
Control Group
ACTIVE COMPARATORThe control group will receive 2500 IU of vitamin D3 daily.
Dosing Algorithm Group
EXPERIMENTALThe dosing algorithm group will initially receive 1000, 2500, or 4000 IU of vitamin D3 daily based on the baseline 25(OH)D. This group's dosing may be adjusted at the 3-month visit.
Interventions
Gelcaps containing 1000, 2500, and 4000 IU of vitamin D3 will be obtained from Tischon corporation (Westbury, NY). The gelcaps will be protected from light and not stored above 25° C. Participants will be instructed to take their vitamin D3 gelcaps with supper daily. Compliance with study supplementation will be documented by pill count at the time of each study visits.
Eligibility Criteria
You may qualify if:
- Healthy, community-dwelling postmenopausal woman of self-reported European (Madison site) or African (Milwaukee site) descent
- Able and willing to sign informed consent
- Baseline serum 25(OH)D concentration of 10.0-29.9 ng/mL
- Willing to not alter the amount of their baseline vitamin D supplementation during the course of this study
- Willing to use sunscreen (SPF ≥15) when sun exposure of \>15 minutes is expected during the months of May through September
You may not qualify if:
- Diagnosis of kidney or liver disease (organs that metabolize vitamin D)
- Current hypercalcemia (serum calcium ≥ 10.5 mg/dL) or other disorders that may affect vitamin D metabolism and predispose to hypercalcemia, i.e., sarcoidosis, active tuberculosis or other granulomatous disease.
- Other chronic diseases or conditions potentially affecting vitamin D metabolism or absorption (inflammatory bowel disease, cystic fibrosis, ulcerative colitis, and malabsorptive surgery)
- History of nephrolithiasis
- Current use of medications that affect vitamin D metabolism (glucocorticoids, anticonvulsants, antifungals, and HIV/AIDS medications)
- History of any form of cancer within the past two years with the exception of basal or squamous cell skin lesions, in situ tumors or thyroid cancer
- Terminal illness/on hospice
- Severe end-organ disease (e.g., cardiovascular, pulmonary, etc.), which may limit the ability to complete the study
- Treatment with high dose vitamin D (≥50,000 IU weekly) or any active metabolites of vitamin D, e.g., calcitriol, within six months of screening; current use of multiple vitamins and other vitamin D supplements will be allowed.
- Use of tanning beds or salons or unwillingness to utilize sunscreen during periods of sun exposure of 15 minutes or longer from May through September
- Planned trips/vacations likely to be associated with substantial amounts of sun exposure during the course of the study (i.e., more than 500 miles south of Madison/Milwaukee)
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- University of Wisconsin, Madisonlead
- Medical College of Wisconsincollaborator
Study Sites (2)
University of Wisconsin Osteoporosis Clinical Research Program
Madison, Wisconsin, 53705, United States
Medical College of Wisconsin
Milwaukee, Wisconsin, 53226, United States
MeSH Terms
Conditions
Interventions
Condition Hierarchy (Ancestors)
Intervention Hierarchy (Ancestors)
Results Point of Contact
- Title
- Dr. Corinne D. Engleman
- Organization
- University of Wisconsin
Study Officials
- PRINCIPAL INVESTIGATOR
Corinne Engelman, PhD
University of Wisconsin, Madison
Publication Agreements
- PI is Sponsor Employee
- Yes
Study Design
- Study Type
- interventional
- Phase
- not applicable
- Allocation
- RANDOMIZED
- Masking
- DOUBLE
- Who Masked
- PARTICIPANT, INVESTIGATOR
- Purpose
- TREATMENT
- Intervention Model
- PARALLEL
- Sponsor Type
- OTHER
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
January 22, 2015
First Posted
February 12, 2015
Study Start
October 30, 2015
Primary Completion
May 3, 2019
Study Completion
May 3, 2019
Last Updated
December 1, 2020
Results First Posted
November 13, 2020
Record last verified: 2020-11