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Vitamin D and Vascular Health in Children

This study is currently recruiting participants. (see Contacts and Locations)
Verified March 2017 by University of Pittsburgh
National Heart, Lung, and Blood Institute (NHLBI)
Office of Dietary Supplements (ODS)
Information provided by (Responsible Party):
Kumaravel Rajakumar, University of Pittsburgh Identifier:
First received: February 20, 2013
Last updated: March 9, 2017
Last verified: March 2017
In this study, we will test the central hypothesis that enhancement of vitamin D status in obese and overweight children will improve their vascular health and their cardiovascular disease (CVD) and metabolic syndrome risk profile.

Condition Intervention
Vitamin D Deficiency
Dietary Supplement: Vitamin D3

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Participant, Care Provider, Investigator, Outcomes Assessor
Primary Purpose: Treatment
Official Title: Vitamin D and Vascular Function in Obese Children

Resource links provided by NLM:

Further study details as provided by University of Pittsburgh:

Primary Outcome Measures:
  • brachial artery flow-mediated dilation (FMD) [ Time Frame: 6 months ]
    measure of vascular endothelial function

Secondary Outcome Measures:
  • pulse-wave velocity (PWV) [ Time Frame: 6 months ]
    measure of arterial stiffness

  • fasting glucose/fasting insulin ratio [ Time Frame: 6 months ]
    Homeostasis Model of Assessment - Insulin Resistance (HOMA-IR) as a surrogate estimate of insulin sensitivity

Other Outcome Measures:
  • blood pressure, waist circumference, HDL cholesterol, triglycerides, and fasting blood glucose [ Time Frame: 6 months ]
    components of metabolic syndrome

  • inflammatory markers [ Time Frame: 6 months ]
  • adipokines [ Time Frame: 6 months ]
  • nitric oxide metabolites [ Time Frame: 6 months ]

Estimated Enrollment: 252
Study Start Date: August 2013
Estimated Study Completion Date: October 2018
Estimated Primary Completion Date: January 2018 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Vitamin D3 2000 IU
Vitamin D3 2000 IU tablet once daily by mouth for 6 months
Dietary Supplement: Vitamin D3
Tablet form
Other Name: Cholecalciferol
Active Comparator: Vitamin D3 1000 IU
Vitamin D3 1000 IU tablet by mouth once daily for 6 months
Dietary Supplement: Vitamin D3
Tablet form
Other Name: Cholecalciferol
Placebo Comparator: Vitamin D3 600 IU
Vitamin D3 600 IU tablet by mouth once daily for 6 months
Dietary Supplement: Vitamin D3
Tablet form
Other Name: Cholecalciferol

Detailed Description:
Our primary objective is to determine, in obese and overweight children aged 10 to 18 years with vitamin D deficiency (defined as serum 25-hydroxyvitamin D <20 ng/mL), the efficacy of enhanced vitamin D3 supplementation in improving vascular endothelial function, arterial stiffness, insulin sensitivity, and metabolic syndrome risk status; and to assess whether these effects are dose-dependent. As a secondary objective, we will examine the vitamin D supplementation-induced effect on adipokines and inflammatory markers relevant to CVD risk. In a double-masked, controlled trial, we will randomize 252 eligible children to receive either 600 IU (conventional supplementation), or 1000 IU or 2000 IU (enhanced supplementation) of vitamin D3 daily for 6 months.

Ages Eligible for Study:   10 Years to 18 Years   (Child, Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Eligible subjects will be 10 to 18 years of age;
  • obese or overweight (BMI ≥85th %tile);
  • otherwise healthy, and
  • have a serum 25(OH)D concentration <20 ng/mL

Children taking multivitamins should be able to hold off their multivitamins during the course of the study.

Exclusion Criteria:

Children will be excluded if they

  • (a) have hepatic or renal disease, metabolic rickets, malabsorptive disorders, primary hyperparathyroidism, hyperthyroidism, or other chronic disorders that could affect vitamin D metabolism;
  • (b) are receiving treatment with anticonvulsants, systemic glucocorticoids, pharmacologic doses of vitamin D (≥1000 IU of vitamin D2 or D3 daily), antihypertensives, vasoactive drugs, antilipidemics, metformin, antipsychotics, or other oral insulin regulators;
  • (c) have cholelithiasis or urolithiasis;
  • (d) have type 1 or type 2 diabetes; or
  • (e) have a condition or underlying abnormality that could compromise the safety of the subject.

Post-menarchial girls with a positive pregnancy test at randomization, or subjects found during the screening phase to have hypercalcemia (serum calcium >10.8 mg/dL) or significant fasting hyperglycemia (fasting blood glucose ≥ 125 mg/dL) will also be excluded.

  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01797302

Contact: Flora Olabopo, BS 412-692-8737
Contact: Kumaravel Rajakumar, MD, MS 412-692-5415

United States, Pennsylvania
Primary Care Center, Children's Hospital of Pittsburgh of UPMC Recruiting
Pittsburgh, Pennsylvania, United States, 15213
Principal Investigator: Kumaravel Rajakumar, MD, MS         
Sponsors and Collaborators
University of Pittsburgh
National Heart, Lung, and Blood Institute (NHLBI)
Office of Dietary Supplements (ODS)
Principal Investigator: Kumaravel Rajakumar, MD, MS University of Pittsburgh, Children's Hospital of Pittsburgh of UPMC
  More Information

Responsible Party: Kumaravel Rajakumar, Associate Professor of Pediatrics, University of Pittsburgh Identifier: NCT01797302     History of Changes
Other Study ID Numbers: PRO12100034
R01HL112985 ( US NIH Grant/Contract Award Number )
5R01HL112985-05 ( US NIH Grant/Contract Award Number )
Study First Received: February 20, 2013
Last Updated: March 9, 2017

Keywords provided by University of Pittsburgh:
Vitamin D Deficiency
Vascular Function
Insulin resistance
metabolic syndrome

Additional relevant MeSH terms:
Vitamin D Deficiency
Deficiency Diseases
Nutrition Disorders
Vitamin D
Growth Substances
Physiological Effects of Drugs
Bone Density Conservation Agents processed this record on May 23, 2017