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Characterization of Hyperparathyroidism and Vitamin D Deficiency in Obesity

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified July 2007 by Weill Medical College of Cornell University.
Recruitment status was:  Active, not recruiting
Information provided by:
Weill Medical College of Cornell University Identifier:
First received: February 6, 2006
Last updated: July 19, 2007
Last verified: July 2007

Obese persons are known to have elevated levels of parathyroid hormone (PTH) and low levels of vitamin D. These hormones are important in regulation of the body’s calcium stores and bone health. We would like to investigate these abnormalities and the accuracy of our current diagnostic tests by comparing results of standard assays for vitamin D and PTH to more specific tests, in obese subjects at baseline and as vitamin D is replaced. We will also compare two standard vitamin D replacement regimens to determine if one is more effective.

This is a pilot study with two parts: Part 1 will compare levels of PTH and vitamin D using two different assays in obese subjects who have normal vitamin D and those who do not. We plan to enroll 20 subjects who have normal vitamin D levels and 40 subjects who have vitamin D insufficiency. All subjects will fill out questionnaires about the amount of calcium and vitamin D in their diet, and their recent sunlight exposure. We will ask for blood samples so that we can measure levels of calcium, vitamin D, albumin, creatinine, glucose, insulin and the different forms of PTH.

Subjects who have vitamin D insufficiency will then be randomized to receive Vitamin D2 or Vitamin D3 in standard doses for eight weeks, in an open label trial. At four and eight weeks, these subjects will fill out the above questionnaires and have the blood tests repeated. For safety purposes, urine calcium will also be monitored.

Condition Intervention Phase
Vitamin D Deficiency
Secondary Hyperparathyroidism
Drug: Ergocalciferol
Drug: Cholecalciferol
Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Characterization of Hyperparathyroidism and Vitamin D Deficiency in Obesity

Resource links provided by NLM:

Further study details as provided by Weill Medical College of Cornell University:

Primary Outcome Measures:
  • Vitamin D (25OHD):RIA and HPLC
  • Parathyroid hormone (PTH):iPTH and 3rd generation RIA

Secondary Outcome Measures:
  • Parathyroid hormone carboxy terminal fragment levels PTH(7-84)
  • Ratio of PTH (1-84) to PTH (7-84)
  • Serum calcium level
  • Urine calcium level

Estimated Enrollment: 60
Study Start Date: February 2006
Estimated Study Completion Date: July 2007

Ages Eligible for Study:   18 Years to 65 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Obese subjects with body mass indices greater than 40 kg/m2 or 35 kg/m2 with other medical conditions secondary to obesity
  • Willingness to take vitamin D supplements
  • If baseline vitamin D level is >25 ng/ml subjects will be eligible for the control group
  • If baseline vitamin D level is <25 ng/ml subjects will be eligible for one of the two vitamin D replacement groups

Exclusion Criteria:

  • Hypercalcemia
  • Kidney disease
  • Liver disease
  • Malabsorption
  • Prior diagnosis of bone disease
  • Medical conditions requiring daily use of calcium, antacids, or medications known to affect bone metabolism or interact with vitamin D
  • Hypersensitivity to any formulation of vitamin D
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Please refer to this study by its identifier: NCT00288873

United States, New York
Weill Cornell Medical College
New York, New York, United States, 10021
Sponsors and Collaborators
Weill Medical College of Cornell University
Principal Investigator: Emily M Stein, M.D. Weill Medical College of Cornell University
  More Information

Publications automatically indexed to this study by Identifier (NCT Number): Identifier: NCT00288873     History of Changes
Other Study ID Numbers: 0509008122
Study First Received: February 6, 2006
Last Updated: July 19, 2007

Keywords provided by Weill Medical College of Cornell University:
Vitamin D deficiency
Secondary hyperparathyroidism

Additional relevant MeSH terms:
Vitamin D Deficiency
Hyperparathyroidism, Secondary
Nutrition Disorders
Body Weight
Signs and Symptoms
Parathyroid Diseases
Endocrine System Diseases
Deficiency Diseases
Vitamin D
Growth Substances
Physiological Effects of Drugs
Bone Density Conservation Agents processed this record on April 28, 2017