Effect of an Inhibitor of Cholesterol Absorption on Vitamin D Levels

Study Overview
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Brief Summary
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Double-blind randomized controlled trial to evaluate the serum levels of 25(OH)D after a single oral dose of cholecalciferol 50,000 IU plus ezetimibe or placebo. Differences between the serum levels of 25(OH)D in response to cholecalciferol plus ezetimibe compared to cholecalciferol plus placebo.

Detailed Description
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Objectives: To evaluate the serum levels of 25(OH)D after a single oral dose of cholecalciferol 50,000 IU plus ezetimibe or placebo. Experimental design: Double-blind randomized controlled trial. Research location: Porto Alegre Clinical Hospital (HCPA), RS, Brazil. Participants: Medical residents of the HCPA. Intervention: The groups will be randomized to ezetimibe 10 mg for 5 days or placebo. On the fifth day, they should came after an overnight fast for blood tests collection [25(OH)D, PTH, calcium, albumin]. Next, all participants will receive orally a cholecalciferol 50,000 IU capsule and a snack containing 15g of fat. Participants will return 14 days after that for a second blood test. Statistical Analysis: Paired samples t-test or Wilcoxon signed rank-test will be used for comparing variables in two distinct moments (before cholecalciferol and 14 days after). The correlation between the numerical variables will be evaluated by the Spearman's correlation coefficient. A p value of less than 0.05 was considered statistically significant. Expected results: Differences between the serum levels of 25(OH)D in response to cholecalciferol plus ezetimibe compared to cholecalciferol plus placebo. Cost/benefit of the project: This is a low budget and minimal risks study that will contribute to a better understanding of the absorptive process of vitamin D and the effect of ezetimibe on its absorption.

Official Title
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Estudo clínico Randomizado, Controlado e Duplo-cego do Impacto da inibição de um Transportador de Membrana do Colesterol na absorção da Vitamina D

Conditions
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Vitamin D Deficiency

Intervention / Treatment
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* Drug: Ezetimibe
* Drug: Cholecalciferol
* Other: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Medical students of the HCPA Exclusion Criteria: Body mass index >+ 25 or < 18.5 kg/m2 Known liver, kidney or endocrine disease Known malabsorption Use of supplements of calcium and/or vitamin Danticonvulsants, barbiturates, or glucocorticoids Travel outside the Brazilian south region during the previous 120 days

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Factorial Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Placebo + Cholecalciferol<br>The groups will be randomized to ezetimibe or placebo. All participants will receive orally a cholecalciferol capsule. | Drug: Cholecalciferol<br>* All participants will receive orally a cholecalciferol 50,000 IU capsule and a snack containing 15g of fat. Participants will return 14 days after that for a second blood test.<br>* Other names: Vitamin D;Other: Placebo<br>* The groups will be randomized to ezetimibe 10 mg for 5 days or placebo. On the fifth day, they should came after an overnight fast for blood tests collection [25(OH)D, PTH, calcium, albumin]. Next, all participants will receive orally a cholecalciferol 50,000 IU capsule and a snack containing 15g of fat. Participants will return 14 days after that for a second blood test.<br>|
| Active Comparator: Ezetimibe + Cholecalciferol<br>The groups will be randomized to ezetimibe or placebo. All participants will receive orally a cholecalciferol capsule. | Drug: Ezetimibe<br>* The groups will be randomized to ezetimibe 10 mg for 5 days or placebo. On the fifth day, they should came after an overnight fast for blood tests collection [25(OH)D, PTH, calcium, albumin]. Next, all participants will receive orally a cholecalciferol 50,000 IU capsule and a snack containing 15g of fat. Participants will return 14 days after that for a second blood test.<br>Drug: Cholecalciferol<br>* All participants will receive orally a cholecalciferol 50,000 IU capsule and a snack containing 15g of fat. Participants will return 14 days after that for a second blood test.<br>* Other names: Vitamin D;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 25-hydroxyvitamin D | The groups will be randomized to ezetimibe 10 mg for 5 days or placebo. On the fifth day, they should came after an overnight fast for blood tests collection [25(OH)D, PTH, calcium, albumin]. Next, all participants will receive orally a cholecalciferol 50,000 IU capsule and a snack containing 15g of fat. Participants will return 14 days after that for a second blood test. | up to 24 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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vitamin D, absorption, ezetimibe