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Vitamin D and Vascular Health in Children

10. juni 2020 opdateret af: Kumaravel Rajakumar, University of Pittsburgh

Vitamin D and Vascular Function in Obese Children

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.

Studieoversigt

Status

Afsluttet

Betingelser

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)

  1. Waist Circumference
  2. Serum High Density Lipoprotein (HDL) Cholesterol
  3. Serum Triglycerides
  4. Inflammatory markers (Plasma TNF-alpha, high-sensitivity C-reactive protein, and IL-6)
  5. Adiopkines (Plasma Leptin and Adiponectin)

Plasma nitric oxide metabolites were not measured.

Undersøgelsestype

Interventionel

Tilmelding (Faktiske)

225

Fase

  • Ikke anvendelig

Kontakter og lokationer

Dette afsnit indeholder kontaktoplysninger for dem, der udfører undersøgelsen, og oplysninger om, hvor denne undersøgelse udføres.

Studiesteder

    • Pennsylvania
      • Pittsburgh, Pennsylvania, Forenede Stater, 15213
        • Primary Care Center, Children's Hospital of Pittsburgh of UPMC

Deltagelseskriterier

Forskere leder efter personer, der passer til en bestemt beskrivelse, kaldet berettigelseskriterier. Nogle eksempler på disse kriterier er en persons generelle helbredstilstand eller tidligere behandlinger.

Berettigelseskriterier

Aldre berettiget til at studere

10 år til 18 år (Barn, Voksen)

Tager imod sunde frivillige

Ja

Køn, der er berettiget til at studere

Alle

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

Dette afsnit indeholder detaljer om studieplanen, herunder hvordan undersøgelsen er designet, og hvad undersøgelsen måler.

Hvordan er undersøgelsen tilrettelagt?

Design detaljer

  • Primært formål: Behandling
  • Tildeling: Randomiseret
  • Interventionel model: Parallel tildeling
  • Maskning: Firedobbelt

Våben og indgreb

Deltagergruppe / Arm
Intervention / Behandling
Aktiv komparator: Vitamin D3 2000 IU
Vitamin D3 2000 IU tablet once daily by mouth for 6 months
Tablet form
Andre navne:
  • Cholecalciferol
Aktiv komparator: Vitamin D3 1000 IU
Vitamin D3 1000 IU tablet by mouth once daily for 6 months
Tablet form
Andre navne:
  • Cholecalciferol
Placebo komparator: Vitamin D3 600 IU
Vitamin D3 600 IU tablet by mouth once daily for 6 months
Tablet form
Andre navne:
  • Cholecalciferol

Hvad måler undersøgelsen?

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

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
Central Systolic Blood Pressure
Tidsramme: 6 months
a measure of cardiometabolic health
6 months
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

Resultatmål
Foranstaltningsbeskrivelse
Tidsramme
Body Mass Index (BMI)
Tidsramme: 6 months
a surrogate measure of adiposity
6 months

Samarbejdspartnere og efterforskere

Det er her, du vil finde personer og organisationer, der er involveret i denne undersøgelse.

Efterforskere

  • Ledende efterforsker: Kumaravel Rajakumar, MD, MS, University of Pittsburgh, Children's Hospital of Pittsburgh of UPMC

Publikationer og nyttige links

Den person, der er ansvarlig for at indtaste oplysninger om undersøgelsen, leverer frivilligt disse publikationer. Disse kan handle om alt relateret til undersøgelsen.

Datoer for undersøgelser

Disse datoer sporer fremskridtene for indsendelser af undersøgelsesrekord og resumeresultater til ClinicalTrials.gov. Studieregistreringer og rapporterede resultater gennemgås af National Library of Medicine (NLM) for at sikre, at de opfylder specifikke kvalitetskontrolstandarder, før de offentliggøres på den offentlige hjemmeside.

Studer store datoer

Studiestart (Faktiske)

1. august 2013

Primær færdiggørelse (Faktiske)

13. august 2018

Studieafslutning (Faktiske)

13. august 2018

Datoer for studieregistrering

Først indsendt

20. februar 2013

Først indsendt, der opfyldte QC-kriterier

20. februar 2013

Først opslået (Skøn)

22. februar 2013

Opdateringer af undersøgelsesjournaler

Sidste opdatering sendt (Faktiske)

24. juni 2020

Sidste opdatering indsendt, der opfyldte kvalitetskontrolkriterier

10. juni 2020

Sidst verificeret

1. juni 2020

Mere information

Begreber relateret til denne undersøgelse

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Kliniske forsøg med Vitamin D3

Abonner