Vitamin D and Vascular Health in Children
Vitamin D and Vascular Function in Obese Children
Studieoversigt
Status
Status
Betingelser
Betingelser
Intervention / Behandling
Intervention / Behandling
Detaljeret beskrivelse
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.
Undersøgelsestype
Undersøgelsestype
Tilmelding (Faktiske)
Tilmelding
Fase
Fase
- Ikke anvendelig
Kontakter og lokationer
Studiesteder
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-
Pennsylvania
-
Pittsburgh, Pennsylvania, Forenede Stater, 15213
- Primary Care Center, Children's Hospital of Pittsburgh of UPMC
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-
Deltagelseskriterier
Berettigelseskriterier
Berettigelseskriterier
Aldre berettiget til at studere
Tager imod sunde frivillige
Køn, der er berettiget til at studere
Beskrivelse
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.
Studieplan
Hvordan er undersøgelsen tilrettelagt?
Design detaljer
- Primært formål: Behandling
- Tildeling: Randomiseret
- Interventionel model: Parallel tildeling
- Maskning: Firedobbelt
Antal våben
Våben og indgreb
Deltagergruppe / ArmDeltagergruppe / Arm |
Intervention / BehandlingIntervention / Behandling |
|---|---|
|
Aktiv komparator: Vitamin D3 2000 IU
Vitamin D3 2000 IU tablet once daily by mouth for 6 months
|
Tablet form
Andre navne:
|
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Aktiv komparator: Vitamin D3 1000 IU
Vitamin D3 1000 IU tablet by mouth once daily for 6 months
|
Tablet form
Andre navne:
|
|
Placebo komparator: Vitamin D3 600 IU
Vitamin D3 600 IU tablet by mouth once daily for 6 months
|
Tablet form
Andre navne:
|
Hvad måler undersøgelsen?
Primære resultatmål
Primære resultatmål
Resultatmål |
Foranstaltningsbeskrivelse |
Tidsramme |
|---|---|---|
|
Flow-mediated Dilation (FMD) Percentage
Tidsramme: 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.
|
6 months
|
Sekundære resultatmål
Sekundære resultatmål
Resultatmål |
Foranstaltningsbeskrivelse |
Tidsramme |
|---|---|---|
|
Pulse-wave Velocity (PWV)
Tidsramme: 6 months
|
PWV is a measure of arterial stiffness.
Higher values of PWV indicate greater degree of arterial stiffness.
|
6 months
|
|
Augmentation Index at Heart Rate of 75 Beats/Min (AIx-75)
Tidsramme: 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
Tidsramme: 6 months
|
a measure of cardiometabolic health
|
6 months
|
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Central Diastolic Blood Pressure
Tidsramme: 6 months
|
a measure of cardiometabolic health
|
6 months
|
|
Systemic Systolic Blood Pressure
Tidsramme: 6 months
|
a measure of cardiometabolic health
|
6 months
|
|
Systemic Diastolic Blood Pressure
Tidsramme: 6 months
|
a measure of cardiometabolic health
|
6 months
|
|
Fasting Blood Glucose
Tidsramme: 6 months
|
a measure of cardiometabolic health
|
6 months
|
|
1/Fasting Insulin Ratio
Tidsramme: 6 months
|
1/fasting insulin ratio is a measure of insulin sensitivity.
Increases in 1/fasting insulin ratio indicate improvements in insulin sensitivity.
|
6 months
|
Andre resultatmål
Andre resultatmål
Resultatmål |
Foranstaltningsbeskrivelse |
Tidsramme |
|---|---|---|
|
Body Mass Index (BMI)
Tidsramme: 6 months
|
a surrogate measure of adiposity
|
6 months
|
Samarbejdspartnere og efterforskere
Sponsor
Sponsor
Samarbejdspartnere
Samarbejdspartnere
Efterforskere
Efterforskere
- Ledende efterforsker: Kumaravel Rajakumar, MD, MS, University of Pittsburgh, Children's Hospital of Pittsburgh of UPMC
Publikationer og nyttige links
Datoer for undersøgelser
Studer store datoer
Studiestart (Faktiske)
Studiestart
Primær færdiggørelse (Faktiske)
Primær færdiggørelse
Studieafslutning (Faktiske)
Studieafslutning
Datoer for studieregistrering
Først indsendt
Først indsendt
Først indsendt, der opfyldte QC-kriterier
Først indsendt, der opfyldte QC-kriterier
Først opslået (Skøn)
Først opslået
Opdateringer af undersøgelsesjournaler
Sidste opdatering sendt (Faktiske)
Sidste opdatering sendt
Sidste opdatering indsendt, der opfyldte kvalitetskontrolkriterier
Sidste opdatering indsendt, der opfyldte kvalitetskontrolkriterier
Sidst verificeret
Sidst verificeret
Mere information
Begreber relateret til denne undersøgelse
Yderligere relevante MeSH-vilkår
Andre undersøgelses-id-numre
Andre undersøgelses-id-numre
- PRO12100034
- R01HL112985 (U.S. NIH-bevilling/kontrakt)
- 5R01HL112985-05 (U.S. NIH-bevilling/kontrakt)
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