Vitamin D Supplementation in CAD and Postchallenge Hyperglycemia

Effects of Vitamin D Supplementation in Coronary Artery Disease Patients With Postchallenge Hyperglycemia and Vitamin D Deficiency on Endothelial Function and Insulin Sensitivity

The main aim of the investigation is to clarify, whether vitamin D supplementation in coronary artery disease patients with vitamin D deficiency and postchallenge hyperglycemia has an impact on endothelial dysfunction and parameters of insulin sensitivity and beta-cell function.

Study Overview

• Status: Terminated
• Conditions: Coronary Artery Disease; Vitamin D Deficiency; Postprandial Hyperglycemia
• Intervention / Treatment: Drug: vitamin D

Detailed Description

An improvement of endothelial dysfunction as a cardiovascular surrogate parameter could be translated in a reduced risk for future cardiovascular events, which is of major interest, since patients with postchallenge hyperglycemia face a significantly higher cardiovascular risk than patients with normal glucose tolerance. Furthermore an improvement in insulin sensitivity and/or beta-cell function would identify vitamin D as an important strategy for the prevention of type 2 diabetes. In consideration of the rapidly increasing prevalence of diabetes and the failure of current prevention strategies this could be an important, safe and cheap way to support ongoing lifestyle modifying programs. Our study of course investigates surrogate cardiovascular and insulin sensitivity parameters. Assuming a beneficial effect of vitamin D in our study, this concept would have to be proven in further large outcome as well as diabetes prevention trials.

• Study Type: Interventional
• Enrollment (Actual): 22
• Phase: Phase 3

Contacts and Locations

Study Locations

• Austria
  • Graz, Austria, 8036
    • Dept. of Internal Medicine, Medical University of Graz

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 40 years to 75 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age 40-75
• Postchallenge hyperglycemia (2h-whole blood glucose value in oral glucose tolerance test above 119 mg/dl, normal fasting glucose)
• Angiographically verified coronary artery disease (>50% stenosis)
• Serum 25-OH- vitamin D < 20 ng/ml in winter/spring/autumn and <25 ng/ml during june-september
• Stable antihypertensive therapy in the last 3 month

Exclusion Criteria:

• Acute coronary syndrome or cerebrovascular event within the previous 1 month
• BMI > 40 kg/m²
• Serum creatinine >2.5 times the upper limit of normal
• GOT or GPT > 3 times the upper limit of normal
• Heart failure > NYHA class II
• Uncontrolled hypertension (>160/100 mmHg)
• New onset of statins, ACE-inhibitors or ARBs within the previous 4 weeks
• History of urolithiasis
• Hypercalcaemia
• Major psychiatric disorders
• Ongoing treatment with spironolactone, canrenoate, eplerenone, amiloride, triamterene and aliskiren.
• Treatment with antipsychotic drugs
• Regular significant antioxidants, vitamins or protein supplementation
• Immunosuppressive therapy
• Glucocorticoid therapy
• Ongoing chemotherapy
• Pregnancy
• Any other disease with an estimated life expectancy below 1 year.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: vitamin D (Oleovit®); vitamin D drops	Drug: vitamin D; orally administered 2800 IU of vitamin D or placebo daily; Other Names: vitamin d (Oleovit®)
Placebo Comparator: Placebo; placebo drops	Drug: vitamin D; orally administered 2800 IU of vitamin D or placebo daily; Other Names: vitamin d (Oleovit®)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
endothelial dysfunction	Changes in endothelial dysfunction (peripheral artery tone (PAT) and biochemical)	1 year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
insulin resistance and beta-cell function	Changes in indices for insulin resistance and beta-cell function	1 year

Collaborators and Investigators

• Sponsor: Medical University of Graz
• Investigators: Principal Investigator: Thomas R. Pieber, MD, Medical University of Graz, Graz, Austria

Study record dates

Study Major Dates

• Study Start: June 1, 2010
• Primary Completion (Actual): November 1, 2012
• Study Completion (Actual): November 1, 2012

Study Registration Dates

• First Submitted: August 16, 2010
• First Submitted That Met QC Criteria: August 16, 2010
• First Posted (Estimate): August 17, 2010

Study Record Updates

• Last Update Posted (Estimate): April 17, 2015
• Last Update Submitted That Met QC Criteria: April 16, 2015
• Last Verified: April 1, 2015

More Information

Terms related to this study

• Keywords: insulin sensitivity; endothelial function
• Additional Relevant MeSH Terms: Heart Diseases; Cardiovascular Diseases; Vascular Diseases; Glucose Metabolism Disorders; Metabolic Diseases; Arteriosclerosis; Arterial Occlusive Diseases; Nutrition Disorders; Avitaminosis; Deficiency Diseases; Malnutrition; Hyperglycemia; Coronary Artery Disease; Myocardial Ischemia; Coronary Disease; Vitamin D Deficiency; Physiological Effects of Drugs; Micronutrients; Bone Density Conservation Agents; Calcium-Regulating Hormones and Agents; Vitamin D; Cholecalciferol; Vitamins; Ergocalciferols
• Other Study ID Numbers: ENM-DA012