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Phase 3 N=62 Randomized Double-blind Diagnostic

Improving the Understanding of the Response to Vitamin D Supplementation

Vitamin D Deficiency

Enrolled (actual)
62
Serious AEs
0.0%
Results posted
Nov 2016
Primary outcome: Primary: Change in Serum 25-hydroxy Vitamin D3 — 6.0; -0.8; 10.4; 0.3 ng/ml

Study Design & Population

Study type
Interventional
Phase
Phase 3
Interventions
cholecalciferol (Dietary_supplement); Placebo (Dietary_supplement)
Age
Adult, Older Adult · 50+ yrs
Sex
Female
Sponsor
University of Wisconsin, Madison
Primary completion
Dec 2014

Outcome Measures

OutcomeResultp-value
PRIMARY
Change in Serum 25-hydroxy Vitamin D3
6.0; -0.8; 10.4; 0.3
SECONDARY
Change in Parameters of the Vitamin D Assay Panel
6.7; -0.6; 6.7; -0.20; 0.3; -0.2

Summary

It is the investigators hypothesis that the current method of evaluating vitamin D status, measuring circulating 25-hydroxy vitamin D is not providing the full metabolic picture, and is therefore inadequate. The investigators liken this concept to the evolution of cholesterol where initially, total cholesterol was the only measurement, and have since determined the importance of HDL, LDL and triglycerides in evaluating patient status. Similarly, the investigators feel measurement of other vitamin D components such as sulfated vitamin D, circulating vitamin D3 and 3-epi 25-hydroxy vitamin D will offer more comprehensive information about a patient's vitamin D status. It is our overarching hypothesis that a "vitamin D assay panel," will enhance understanding of vitamin D status. It is our expectation that the enhanced understanding based on improved measurement capability will ultimately translate to improved definition of vitamin D status and need for supplementation on an individual level.

Eligibility Criteria

Inclusion Criteria

  • Healthy, community-dwelling ambulatory postmenopausal White, non-Hispanic women
  • Able and willing to sign informed consent
  • Baseline serum 25(OH)D concentration of 10-29 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

Exclusion Criteria

  • Presence of any measurable circulating 25(OH)D2 on screening measurement
  • Current hypercalcemia (serum calcium > 10.5 mg/dl) or untreated primary hyperparathyroidism
  • History of nephrolithiasis
  • Known risk factors for hypercalcemia, e.g., malignancy, tuberculosis, sarcoidosis
  • History of any form of cancer within the past five years with the exception of adequately treated squamous cell or basal cell skin carcinoma
  • Renal failure; defined as a calculated creatinine clearance (using the Cockroft-Gault approach) of ≤ 35 ml/minute
  • Severe end-organ disease, e.g., cardiovascular, hepatic, hematologic, pulmonary, etc., which might limit the ability to complete this study
  • Known metabolic bone disease, e.g., Paget's disease, osteomalacia
  • Treatment with any drug known to interfere with vitamin D metabolism, e.g., phenytoin, phenobarbital
  • 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
  • Use of tanning beds or salons or unwillingness to utilize sunscreen during periods of sun exposure of 15 minutes or longer
  • Planned trips/vacations likely to be associated with substantial amounts of sun exposure during the course of the study
View full record on ClinicalTrials.gov →

Data sourced from ClinicalTrials.gov (NCT01465178). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication.

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