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Vascular and Metabolic Effects of Vitamin D Supplementation Associated With Lifestyle Management in Obese Adolescents

Phase 4
Completed
Conditions
Obesity
Interventions
Other: Normal control
Drug: Placebo
Other: 3 months lifestyle and dietary management
Registration Number
NCT02400151
Lead Sponsor
Centre Hospitalier Universitaire de Nīmes
Brief Summary

The main objective of this study is to analyze in a population of obese adolescents, the effect of vitamin D3 supplementation in addition to lifestyle and dietary management on vascular function assessed by the change between M0 and M3 of endothelium-dependent vasorelaxation measured at the brachial artery (Flow-Mediated Dilation).

Detailed Description

The secondary objectives of this study are:

A. To analyze in obese adolescents, the effect of the addition of vitamin D3 supplementation on metabolic and vascular function.

B. To compare the relationships between food intake, metabolic, inflammatory, oxidative stress and vitamin D status, and vascular dysfunction between obese and normal weight subjects.

C. To evaluate the effects of sun exposure variations on relationships described in Objective B by comparing the observed parameters at baseline and at the end of the three month follow-up period, in non-supplemented obese adolescents and adolescents of normal weight.

D. To identify biomarkers (metabolic signatures) in obese adolescents associated with vitamin D deficiency and vascular function.

E. To evaluate in obese adolescents, the effects of vitamin D supplementation on the metabolome (metabolic signature).

F. To evaluate the effects of lifestyle and dietary management on these biomarkers (in the "control group").

For these targets (A to F), all teenagers will be classified according to three levels of skin pigmentation.

G. Establish a biobank of samples taken at baseline and at 3 months.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
49
Inclusion Criteria
  • The patient's legal representatives must have given their informed and signed consent
  • The patient must be insured or beneficiary of a health insurance plan
  • Sexual maturation of at least Tanner stage 2

Inclusion criteria for the patient population

  • The subject has a body mass index corresponding to grade 2 obesity according to the curves described by Rolland-Cachera et al (1991)
  • Absence of at least 5% of total weight over the last 3 months

Inclusion criteria for the control population

  • The subject has a body mass index < 90th percentile
Exclusion Criteria
  • The patient is participating in another study
  • The patient is in an exclusion period determined by a previous study
  • The patient is under judicial protection
  • The patient's legal representative(s) refuse(s) to sign the consent
  • It is impossible to correctly inform the patient or his/her legal representative(s)
  • The patient has a contraindication for physical activity (joint, heart or other)
  • The subject does at least 3 hours of extracurricular physical activity per week
  • The subject has a concomitant illness, a history of first-degree cardiovascular disease, abnormal glucose tolerance (pre-diabetes or diabetes).
  • Active smoking
  • Known dyslipidemia (particularly hypercholesterolemia).
  • The subject regularly takes food and vitamin supplements and refuses to stop taking these during the study (in case of disruption of these supplements, a wash-out stopping period of 3 weeks is required).
  • BMI corresponding to a grade 1 obesity according to the Rolland-Cachera et al. (1991) curves.
  • Secondary or known genetic obesity.
  • Known hypersensitivity to vitamin D.
  • Hypercalcemia, hypercalciuria, calcium lithiasis

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Non-Obese groupNormal controlNon-obese patients will be recruited and frequency matched to obese groups according to sex and level of sexual maturation. Intervention: Normal control
Obese group, Vitamin D3 months lifestyle and dietary managementSubjects randomized to this group will receive vitamin D supplementation. They are recruited from the St Pierre Institute at Palavas-les-Flots, France. Intervention: 3 months lifestyle and dietary management Intervention: Vitamin D supplementation
Obese group, placeboPlaceboSubjects randomized to this group will receive a placebo supplement. They are recruited from the St Pierre Institute at Palavas-les-Flots, France. Intervention: 3 months lifestyle and dietary management Intervention: Placebo
Obese group, placebo3 months lifestyle and dietary managementSubjects randomized to this group will receive a placebo supplement. They are recruited from the St Pierre Institute at Palavas-les-Flots, France. Intervention: 3 months lifestyle and dietary management Intervention: Placebo
Obese group, Vitamin DVitamin D supplementationSubjects randomized to this group will receive vitamin D supplementation. They are recruited from the St Pierre Institute at Palavas-les-Flots, France. Intervention: 3 months lifestyle and dietary management Intervention: Vitamin D supplementation
Primary Outcome Measures
NameTimeMethod
Change from baseline in Flow Mediated Dilation (%) at the brachial artery3 months
Secondary Outcome Measures
NameTimeMethod
Change from baseline in brachial compliance (mm^2mmHg^-1)3 months
Change from baseline in Isoprostanes (ng*L^-1)3 months
Change from baseline in nitrite-nitrate (µmol*L^-1)3 months
Change from baseline in PAI-1 (µmol*L^-1)3 months
Metabolomic profile3 months
Change from baseline in Nitrate Mediated Dilation (%) at the brachial artery3 months
Change from baseline in arterial wave speed (m*s^-1)3 months
Usual Vitamin D intake according to food questionnaireBaseline
Change from baseline in adiponectin (pg*mL^-1)3 months
Change from baseline in serum calcium levels (mmol*L^-1)3 months
Change from baseline in Homeostatic model assessment Insulin Resistance3 months
Change from baseline in the ratio Low Density Lipoprotein/High Density Lipoprotein3 months
Change from baseline in Triglyceride levels3 months
Change from baseline in SuperOxyde Dismutase (U*gHb^-1)3 months
Change from baseline in TNF-alpha (pg*mL^-1)3 months
Change from baseline in carotid compliance (mm^2mmHg^-1)3 months
Change from baseline in blood 25(OH)D levels (mmol*L^-1)3 months
Change from baseline in blood parathyroid hormone levels (mmol*L^-1)3 months
Change from baseline in High sensitivity C-reactive protein (pg*mL^-1)3 months
Change from baseline in leptin (pg*mL^-1)3 months
Change from baseline in IL-6 (pg*mL^-1)3 months
Change from baseline in blood total protein levels (g*L^-1)3 months
Change from baseline in Acetylcholine-Cutaneous Blood Flow peak3 months
Change from baseline in Sodium nitroprussiate-Cutaneous Blood Flow peak (%)3 months
Change from baseline in Insulin-Cutaneous Blood Flow peak (%)3 months

Trial Locations

Locations (2)

CHRU de Nîmes - Hôpital Universitaire Carémeau

🇫🇷

Nîmes Cedex 09, France

Institut Saint Pierre

🇫🇷

Palavas-Les-Flots, France

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