Vitamin D, Insulin Sensitivity, and Vascular Associations in Adolescents

Serum 25-hydroxyvitamin D, Vascular Functioning, and Insulin Sensitivity in Adolescent Girls [The DIVA Study (Vitamin D, Insulin, and Vascular Associations)] (Pediatric Physician Training in Translational Research)

Status

Completed

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT01041365

Acronym

DIVA

Enrollment

Registered

2009-12-31

Start date

2009-12-31

Completion date

2013-12-31

Last updated

2014-01-14

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Arterial Stiffness, Flow-mediated Dilation, Insulin Sensitivity

Keywords

insulin sensitivity, vascular function, flow-mediated dilation, arterial stiffness, ethnicity, adolescents, females, glucose tolerance, diabetes, hypertension, cardiovascular

Brief summary

The overall objectives of this study are to examine the relationships between circulating vitamin D, insulin sensitivity, and multiple indices of vascular function and to examine whether vitamin D deficiency in AA is responsible for ethnic differences in insulin sensitivity and hypertension in AA and EA, as well as mechanisms underlying the association between insulin resistance and blood pressure. We hypothesize that 1) serum 25(OH)D is associated with insulin sensitivity and vascular functioning, independent of adiposity, 2) lower insulin sensitivity and vascular functioning in AA relative to EA is due to lower circulating 25(OH)D in AA, and 3) the relationship between insulin resistance and vascular dysfunction is mediated by 25(OH)D. Acronyms: African American (AA), European American (EA), Serum 25-hydroxy vitamin D (25()H)D, Body mass index (BMI), Alabama (AL).

Interventions

None listed

Study design

Observational model

COHORT

Time perspective

CROSS_SECTIONAL

Eligibility

Sex/Gender

FEMALE

Age

14 Years to 18 Years

Healthy volunteers

Yes

Inclusion criteria

* African American or Caucasian ethnicity * Ages 14-18 yrs * Healthy

Exclusion criteria

* BMI-for age and -sex higher than 95th centile on the Centers for Disease Control and Prevention Growth Charts * Use of medication(s) known to influence body composition, vascular function, or glucose metabolism * Pregnancy * Diabetes or any chronic diseases

Design outcomes

Primary

Measure	Time frame
Insulin Sensitivity	Cross sectional study: at the first study visit

Secondary

Measure	Time frame
Vascular Function	Cross sectional study: at the second study visit, within 2 weeks of first study visit

Countries

United States

Outcome results