Vitamin D and Immune Mechanisms of Hypertension in Type 2 Diabetics (VDIM)

This trial will evaluate whether a particular type of circulating white blood cell, monocytes, from type 2 diabetics with high blood pressure and vitamin D deficiency vs. sufficiency will induce hormones that increase blood pressure.

Study Overview

• Status: Active, not recruiting
• Conditions: Hypertension; Diabetes Mellitus, Type 2; Vitamin D Deficiency
• Intervention / Treatment: Diagnostic test: Blood draw

Detailed Description

More than half of patients with type 2 diabetes mellitus develop hypertension, which doubles their risk for cardiovascular disease. Inflammation plays a role in the development of these diseases, and monocytes, a type of white blood cell, may be critical. This study will isolate monocytes from blood samples of patients with type 2 diabetes and high blood pressure who have either high levels of vitamin D or low levels of vitamin D, and determine what their effects are on stimulating production in kidney cells of a hormone that increases blood pressure.

• Study Type: Observational
• Enrollment (Estimated): 40

Contacts and Locations

Study Locations

• United States
  • Missouri
    • St Louis, Missouri, United States, 63110
      • Washington University
    • St Louis, Missouri, United States, 63110
      • Barnes-Jewish & Washington University Diabetes Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 25 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: N/A

• Sampling Method: Non-Probability Sample

Study Population

T2DM patients with hypertension

Description

Inclusion Criteria:

• Type 2 diabetes (T2DM)
• Age: 25-80 years old
• Vitamin 25(OH)D3 levels <20 or >30 ng/ml.
• HbA1c: 5.5%-9.5%
• Blood Pressure: <160/100 mm Hg on BP lowering medications and
• Blood Pressure: >120/80 to 160/100 mmHg without BP lowering medications

Exclusion Criteria:

• Recent weight loss of more than 5% within 3 months prior to screening
• Current Pregnancy
• Hypercalcemia
• Previous heart attack and stroke
• Heart failure
• Atrial fibrillation
• Heavy alcohol consumption
• Extreme diets (Atkins, South Beach)
• Chronic renal failure: stage 4 or worse
• >2 + proteinuria on urine sample
• Chronic diseases known to affect immunity

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Vitamin D Deficient; Type 2 diabetics with high blood pressure and 25-hydroxyvitamin D levels of <20 ng/ml	Diagnostic test: Blood draw; Blood will be drawn to isolate monocytes after 2 weeks off of blood pressure lowering medications.
Vitamin D Sufficient; Type 2 diabetics with high blood pressure and 25-hydroxyvitamin D levels of >30 ng/ml	Diagnostic test: Blood draw; Blood will be drawn to isolate monocytes after 2 weeks off of blood pressure lowering medications.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Renin production by monocytes	Blood will be collected for isolation of monocytes. These cells will then be cultured to determine whether there is monocyte stimulation of a hormone that induces high blood pressure (renin) in kidney cells.	2 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Renin production by monocyte media	Blood will be collected for isolation of monocytes. The media from these cells will then be added to culture to determine whether there is stimulation of a hormone that induces high blood pressure (renin) in kidney cells.	2 weeks

Collaborators and Investigators

• Sponsor: Washington University School of Medicine
• Investigators: Study Director: Carlos Bernal-Mizrachi, MD, Washington University School of Medicine

Study record dates

Study Major Dates

• Study Start (Actual): September 1, 2017
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): December 31, 2026

Study Registration Dates

• First Submitted: October 23, 2017
• First Submitted That Met QC Criteria: November 15, 2017
• First Posted (Actual): November 20, 2017

Study Record Updates

• Last Update Posted (Estimated): December 24, 2025
• Last Update Submitted That Met QC Criteria: December 17, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Endocrine System Diseases; Vascular Diseases; Cardiovascular Diseases; Nutrition Disorders; Metabolic Diseases; Glucose Metabolism Disorders; Diabetes Mellitus; Avitaminosis; Deficiency Diseases; Malnutrition; Nutritional and Metabolic Diseases; Hypertension; Diabetes Mellitus, Type 2; Vitamin D Deficiency; Investigative Techniques; Specimen Handling; Clinical Laboratory Techniques; Diagnostic Techniques and Procedures; Diagnosis; Punctures; Surgical Procedures, Operative; Blood Specimen Collection
• Other Study ID Numbers: 201707063

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No