Vitamin D Supplementation Reduces Renin-Angiotensin System Activity in Obesity

Not Applicable

Completed

• Conditions: Hypertension; Vitamin D Deficiency; Obesity
• Interventions: Dietary Supplement: Vitamin D (cholecalciferol)

• Registration Number: NCT01068418
• Lead Sponsor: Brigham and Women's Hospital

Brief Summary

Hypothesis: Vitamin D supplementation lower renin-angiotensin system activity in obesity.

Specific Aim: To investigate whether Vitamin D supplementation in obesity improves the vascular sensitivity to angiotensin II.

Detailed Description

Vitamin D deficiency and obesity are international epidemics that have both been associated with increased activity of the renin-angiotensin system (RAS). Because increased RAS activity is associated with cardiovascular disease, interventions to lower RAS will have favorable public health impacts.

This study aims to evaluate whether the supplementation of Vitamin D in obese subjects will lower local tissue RAS activity. RAS activity will be evaluated by cross-sectional measurement of RAS components and by quantifying the vascular response to an infusion of angiotensin II. Subjects will be studied while Vitamin D deficient, and will return for repeat study following Vitamin D supplementation, for comparison.

Study Timeline

• Study Start: 2010-02
• Study First Submitted: 2010-02-11
• Study First Submitted QC: 2010-02-12
• Study First Posted: 2010-02-15
• Primary Completion: 2011-09
• Study Completion: 2011-09
• Results First Submitted: 2016-12-22
• Results First Submitted QC: 2016-12-22
• Results First Posted: 2017-02-14
• Status Verified: 2017-03
• Last Update Submitted: 2017-03-01
• Last Update Posted: 2017-03-30

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 26

Inclusion Criteria

• age < 65,
• Cr < 1.6,
• 25-hydroxyvitamin D < 25 ng/mL,
• BMI > 30 kg/m2,
• stage I hypertension.

Exclusion Criteria

• diabetes,
• coronary heart disease,
• heart failure,
• renal failure,
• liver failure,
• hyperparathyroidism,
• granulomatous disease.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Vitamin D3	Vitamin D (cholecalciferol)	15000IU of vitamin D3 daily: open-label, single-arm

Primary Outcome Measures

Name	Time	Method
The Change in the Mean Arterial Blood Pressure in Response to an Infusion of Angiotensin II	baseline and 1 month following vitamin D3 therapy

Secondary Outcome Measures

Name	Time	Method
The Change in Renal Blood Flow in Response to an Infusion of Angiotensin II	baseline and 1 month following vitamin D3 therapy

Trial Locations

Locations (1)

Brigham and Women's Hospital; 🇺🇸 Boston, Massachusetts, United States