Vitamin D Deficiency in Adolescent Girls

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
Sherri-Ann M. Burnett-Bowie, Massachusetts General Hospital
ClinicalTrials.gov Identifier:
NCT01180946
First received: August 11, 2010
Last updated: November 1, 2013
Last verified: November 2013
  Purpose

Fibroblast growth factor 23 (FGF23) is a newly discovered hormone which regulates phosphate and vitamin D levels. In this study, we are looking at what the normal levels of FGF23 are in adolescent girls and how these levels vary with other hormonal measurements. We will also be looking at whether vitamin D supplementation in adolescents who are deficient in vitamin D alters the levels of FGF23 and other factors including insulin resistance.


Condition Intervention
Healthy
Vitamin D Deficiency
Dietary Supplement: ergocalciferol
Other: placebo pill

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Basic Science
Official Title: Vitamin D Deficiency in Adolescent Girls

Resource links provided by NLM:


Further study details as provided by Massachusetts General Hospital:

Primary Outcome Measures:
  • change in FGF23 level with vitamin D repletion [ Time Frame: baseline and 16 weeks ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • change in bone turnover markers with vitamin D repletion [ Time Frame: baseline and 16 weeks ] [ Designated as safety issue: No ]
  • change in mineral metabolism factors with vitamin D repletion [ Time Frame: baseline and 16 weeks ] [ Designated as safety issue: Yes ]
  • change in insulin sensitivity with vitamin D repletion [ Time Frame: baseline and 16 weeks ] [ Designated as safety issue: No ]

Enrollment: 90
Study Start Date: September 2010
Study Completion Date: April 2013
Primary Completion Date: April 2013 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Ergocalciferol
Weekly ergocalciferol for 16 weeks
Dietary Supplement: ergocalciferol
ergocalciferol (a dietary form of vitamin D). 50,000 units by mouth once a week for 16 weeks.
Other Name: vitamin D
Placebo Comparator: Placebo
Placebo pill. Note that all subjects in this arm will receive vitamin D repletion at the conclusion of the study.
Other: placebo pill
placebo pill once weekly for 16 weeks. At the end of the study, subjects in this arm will receive vitamin D repletion

Detailed Description:

Fibroblast growth factor 23 (FGF23) is a newly discovered hormone. Its primary function is to regulate phosphate metabolism, which it does both by directly regulating phosphate excretion through the kidney as well as by regulating vitamin D activity. What controls FGF23 levels is still under investigation; potential factors include dietary phosphate intake and vitamin D levels.

In this pilot study, we aim to investigate what the normal levels of FGF23 are in healthy girls and how these are related to other measurements of bone and mineral metabolism. Since vitamin D deficiency is very common in healthy girls, we expect a subset of the subjects in this study to be vitamin D deficient. We will then randomize these girls to vitamin D repletion or placebo and follow changes in FGF23 levels. Vitamin D deficiency has also been implicated in insulin resistance which is a precursor to diabetes. We will therefore also look at changes in insulin resistance with vitamin D repletion.

  Eligibility

Ages Eligible for Study:   9 Years to 18 Years
Genders Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • healthy girls aged 9-18 years

Exclusion Criteria:

  • significant cardiac, hepatic, oncologic, or psychiatric disease
  • a history of malabsorption, kidney stones, hypoparathyroidism, or growth hormone deficiency
  • pregnancy
  • diabetes mellitus
  • BMI>/= 99th percentile for age and sex
  • fracture within the preceding 3 months
  • hypogonadism (no pubertal development by age 12, absence of menarche by age 14)
  • serum calcium <8 mg/dl or >11 mg/dl
  • radiographic evidence of rickets
  • use of medications know to affect serum phosphate levels including phosphate-binding antacids, sodium etidronate, calcitonin, excessive doses of vitamin D (>1000 units per day), excessive doses of vitamin D (>20,000 units/day), calcitriol, growth hormone, or anti-convulsants.
  • use of hormonal birth control
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01180946

Locations
United States, Massachusetts
Massachusetts General Hospital
Boston, Massachusetts, United States, 02114
Sponsors and Collaborators
Massachusetts General Hospital
Investigators
Principal Investigator: Sherri-Ann Burnett-Bowie, MD, MPH Massachusetts General Hospital
  More Information

Publications:
Responsible Party: Sherri-Ann M. Burnett-Bowie, Assistant Professor of Medicine, Massachusetts General Hospital
ClinicalTrials.gov Identifier: NCT01180946     History of Changes
Other Study ID Numbers: 2010-P-001126/1
Study First Received: August 11, 2010
Last Updated: November 1, 2013
Health Authority: United States: Institutional Review Board

Keywords provided by Massachusetts General Hospital:
FGF23
FGF-23
vitamin D
vitamin D deficiency
insulin resistance
Healthy volunteers

Additional relevant MeSH terms:
Vitamin D Deficiency
Avitaminosis
Deficiency Diseases
Malnutrition
Nutrition Disorders
Ergocalciferols
Vitamin D
Vitamins
Bone Density Conservation Agents
Physiological Effects of Drugs
Pharmacologic Actions
Micronutrients
Growth Substances

ClinicalTrials.gov processed this record on July 20, 2014