Vitamin D and Vascular Health in Children
Vitamin D and Vascular Function in Obese Children
Aperçu de l'étude
Statut
Les conditions
Intervention / Traitement
Description détaillée
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.
Type d'étude
Inscription (Réel)
Phase
- N'est pas applicable
Contacts et emplacements
Lieux d'étude
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Pennsylvania
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Pittsburgh, Pennsylvania, États-Unis, 15213
- Primary Care Center, Children's Hospital of Pittsburgh of UPMC
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Critères de participation
Critère d'éligibilité
Âges éligibles pour étudier
Accepte les volontaires sains
Sexes éligibles pour l'étude
La description
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.
Plan d'étude
Comment l'étude est-elle conçue ?
Détails de conception
- Objectif principal: Traitement
- Répartition: Randomisé
- Modèle interventionnel: Affectation parallèle
- Masquage: Quadruple
Armes et Interventions
Groupe de participants / Bras |
Intervention / Traitement |
|---|---|
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Comparateur actif: Vitamin D3 2000 IU
Vitamin D3 2000 IU tablet once daily by mouth for 6 months
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Tablet form
Autres noms:
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Comparateur actif: Vitamin D3 1000 IU
Vitamin D3 1000 IU tablet by mouth once daily for 6 months
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Tablet form
Autres noms:
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Comparateur placebo: Vitamin D3 600 IU
Vitamin D3 600 IU tablet by mouth once daily for 6 months
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Tablet form
Autres noms:
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Que mesure l'étude ?
Principaux critères de jugement
Mesure des résultats |
Description de la mesure |
Délai |
|---|---|---|
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Flow-mediated Dilation (FMD) Percentage
Délai: 6 months
|
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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Mesures de résultats secondaires
Mesure des résultats |
Description de la mesure |
Délai |
|---|---|---|
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Pulse-wave Velocity (PWV)
Délai: 6 months
|
PWV is a measure of arterial stiffness.
Higher values of PWV indicate greater degree of arterial stiffness.
|
6 months
|
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Augmentation Index at Heart Rate of 75 Beats/Min (AIx-75)
Délai: 6 months
|
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
Délai: 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
Délai: 6 months
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a measure of cardiometabolic health
|
6 months
|
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Systemic Systolic Blood Pressure
Délai: 6 months
|
a measure of cardiometabolic health
|
6 months
|
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Systemic Diastolic Blood Pressure
Délai: 6 months
|
a measure of cardiometabolic health
|
6 months
|
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Fasting Blood Glucose
Délai: 6 months
|
a measure of cardiometabolic health
|
6 months
|
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1/Fasting Insulin Ratio
Délai: 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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Autres mesures de résultats
Mesure des résultats |
Description de la mesure |
Délai |
|---|---|---|
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Body Mass Index (BMI)
Délai: 6 months
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a surrogate measure of adiposity
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6 months
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Collaborateurs et enquêteurs
Parrainer
Collaborateurs
Les enquêteurs
- Chercheur principal: Kumaravel Rajakumar, MD, MS, University of Pittsburgh, Children's Hospital of Pittsburgh of UPMC
Publications et liens utiles
Dates d'enregistrement des études
Dates principales de l'étude
Début de l'étude (Réel)
Achèvement primaire (Réel)
Achèvement de l'étude (Réel)
Dates d'inscription aux études
Première soumission
Première soumission répondant aux critères de contrôle qualité
Première publication (Estimation)
Mises à jour des dossiers d'étude
Dernière mise à jour publiée (Réel)
Dernière mise à jour soumise répondant aux critères de contrôle qualité
Dernière vérification
Plus d'information
Termes liés à cette étude
Mots clés
Termes MeSH pertinents supplémentaires
Autres numéros d'identification d'étude
- PRO12100034
- R01HL112985 (Subvention/contrat des NIH des États-Unis)
- 5R01HL112985-05 (Subvention/contrat des NIH des États-Unis)
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