Vitamin D Supplementation Reduces Renin-Angiotensin System Activity in Obesity
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.
|Obesity Vitamin D Deficiency Hypertension||Dietary Supplement: Vitamin D (cholecalciferol)|
|Study Design:||Intervention Model: Single Group Assignment
Masking: No masking
Primary Purpose: Other
|Official Title:||Vitamin D Deficiency Augments Renin-Angiotensin System Activity in Obesity|
- The Change in the Mean Arterial Blood Pressure in Response to an Infusion of Angiotensin II [ Time Frame: baseline and 1 month following vitamin D3 therapy ]
- The Change in Renal Blood Flow in Response to an Infusion of Angiotensin II [ Time Frame: baseline and 1 month following vitamin D3 therapy ]
|Study Start Date:||February 2010|
|Study Completion Date:||September 2011|
|Primary Completion Date:||September 2011 (Final data collection date for primary outcome measure)|
Experimental: Vitamin D3
15000IU of vitamin D3 daily: open-label, single-arm
Dietary Supplement: Vitamin D (cholecalciferol)
cholecalciferol 15,000 IU daily for 30 days
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.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01068418
|United States, Massachusetts|
|Brigham and Women's Hospital|
|Boston, Massachusetts, United States, 02115|
|Principal Investigator:||Jonathan S Williams, MD, MMSc||Brigham and Women's Hospital|
|Study Director:||Anand Vaidya, MD||Brigham and Women's Hospital|