Vitamin D and Vascular Health in Children
Vitamin D and Vascular Function in Obese Children
Studie Overzicht
Toestand
Conditie
Interventie / Behandeling
Gedetailleerde beschrijving
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.
In terms of reporting of results, the following pre-specified outcomes are included in the primary manuscript (PubMed PMID:31950134 -- see Reference section for citation details)
- Waist Circumference
- Serum High Density Lipoprotein (HDL) Cholesterol
- Serum Triglycerides
- Inflammatory markers (Plasma TNF-alpha, high-sensitivity C-reactive protein, and IL-6)
- Adiopkines (Plasma Leptin and Adiponectin)
Plasma nitric oxide metabolites were not measured.
Studietype
Inschrijving (Werkelijk)
Fase
- Niet toepasbaar
Contacten en locaties
Studie Locaties
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Pennsylvania
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Pittsburgh, Pennsylvania, Verenigde Staten, 15213
- Primary Care Center, Children's Hospital of Pittsburgh of UPMC
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Deelname Criteria
Geschiktheidscriteria
Leeftijden die in aanmerking komen voor studie
Accepteert gezonde vrijwilligers
Geslachten die in aanmerking komen voor studie
Beschrijving
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.
Studie plan
Hoe is de studie opgezet?
Ontwerpdetails
- Primair doel: Behandeling
- Toewijzing: Gerandomiseerd
- Interventioneel model: Parallelle opdracht
- Masker: Verviervoudigen
Wapens en interventies
Deelnemersgroep / Arm |
Interventie / Behandeling |
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Actieve vergelijker: Vitamin D3 2000 IU
Vitamin D3 2000 IU tablet once daily by mouth for 6 months
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Tablet form
Andere namen:
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Actieve vergelijker: Vitamin D3 1000 IU
Vitamin D3 1000 IU tablet by mouth once daily for 6 months
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Tablet form
Andere namen:
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Placebo-vergelijker: Vitamin D3 600 IU
Vitamin D3 600 IU tablet by mouth once daily for 6 months
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Tablet form
Andere namen:
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Wat meet het onderzoek?
Primaire uitkomstmaten
Uitkomstmaat |
Maatregel Beschrijving |
Tijdsspanne |
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Flow-mediated Dilation (FMD) Percentage
Tijdsspanne: 6 months
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Brachial artery flow-mediated dilation percentage is a measure of endothelial function.
FMD percentage calculation is based on baseline brachial artery diameter(brachialADbase) and change in brachial artery diameter (brachialADchange) during post-occlusive reactive hyperemia.
FMD% was determined using the formula (brachialADchange/brachialADbase) x 100.
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6 months
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Secundaire uitkomstmaten
Uitkomstmaat |
Maatregel Beschrijving |
Tijdsspanne |
|---|---|---|
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Pulse-wave Velocity (PWV)
Tijdsspanne: 6 months
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PWV is a measure of arterial stiffness.
Higher values of PWV indicate greater degree of arterial stiffness.
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6 months
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Augmentation Index at Heart Rate of 75 Beats/Min (AIx-75)
Tijdsspanne: 6 months
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AIx-75 is a measure of arterial stiffness. AIx was measured through radial arterial tonometry using SphygmoCor. Radial pulse waveform are analyzed through an automatic software function to determine aortic pulse waveform and aortic or central systolic (cSBP) and diastolic blood pressure (cDBP), and these measurements are further analyzed automatically to calculate AIx. AIx is a composite measure of the magnitude of wave reflection and arterial stiffness in all conduit arteries which affect the timing of the wave reflection. AIx = P2-P1/cSBP-cDBP, where P1 is the height of the incident pressure wave form during systole, P2 is the height of the reflected wave added to the incident wave, cSBP is the aortic systolic BP, and cDBP is the aortic diastolic BP. AIx adjusted to heart rate of 75 beats/min (AIx-75) is a validated index of arterial stiffness, with higher values indicating higher degree of arterial stiffness. |
6 months
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Central Systolic Blood Pressure
Tijdsspanne: 6 months
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a measure of cardiometabolic health
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6 months
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Central Diastolic Blood Pressure
Tijdsspanne: 6 months
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a measure of cardiometabolic health
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6 months
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Systemic Systolic Blood Pressure
Tijdsspanne: 6 months
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a measure of cardiometabolic health
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6 months
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Systemic Diastolic Blood Pressure
Tijdsspanne: 6 months
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a measure of cardiometabolic health
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6 months
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Fasting Blood Glucose
Tijdsspanne: 6 months
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a measure of cardiometabolic health
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6 months
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1/Fasting Insulin Ratio
Tijdsspanne: 6 months
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1/fasting insulin ratio is a measure of insulin sensitivity.
Increases in 1/fasting insulin ratio indicate improvements in insulin sensitivity.
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6 months
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Andere uitkomstmaten
Uitkomstmaat |
Maatregel Beschrijving |
Tijdsspanne |
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Body Mass Index (BMI)
Tijdsspanne: 6 months
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a surrogate measure of adiposity
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6 months
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Medewerkers en onderzoekers
Sponsor
Onderzoekers
- Hoofdonderzoeker: Kumaravel Rajakumar, MD, MS, University of Pittsburgh, Children's Hospital of Pittsburgh of UPMC
Publicaties en nuttige links
Studie record data
Bestudeer belangrijke data
Studie start (Werkelijk)
Primaire voltooiing (Werkelijk)
Studie voltooiing (Werkelijk)
Studieregistratiedata
Eerst ingediend
Eerst ingediend dat voldeed aan de QC-criteria
Eerst geplaatst (Schatting)
Updates van studierecords
Laatste update geplaatst (Werkelijk)
Laatste update ingediend die voldeed aan QC-criteria
Laatst geverifieerd
Meer informatie
Termen gerelateerd aan deze studie
Aanvullende relevante MeSH-voorwaarden
Andere studie-ID-nummers
- PRO12100034
- R01HL112985 (Subsidie/contract van de Amerikaanse NIH)
- 5R01HL112985-05 (Subsidie/contract van de Amerikaanse NIH)
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