Vitamin D Supplementation Requirement in Obese Subjects

Sponsor

Winthrop University Hospital (Other)

Overall Status

Completed

CT.gov ID

NCT00996866

Collaborator

(none)

Enrollment

Location

Arms

Duration (Months)

0.7

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

Vitamin D deficiency is common in obese patients. Most of vitamin D supplementation studies were done with non-obese subjects. This study looks at vitamin D supplementation requirements in obese patients as compared to non-obese subjects. This study also looks at changes in vitamin D level in obese patients undergoing medical weight loss. It is thought that obese patients have vitamin D deficiency through storage of vitamin D in the fat compartment not readily available for blood measurement. The investigators' hypothesis is that with medical weight loss vitamin D levels will increase in obese subjects.

Condition or Disease	Intervention/Treatment	Phase
Vitamin D Deficiency	Drug: Vitamin D3 Drug: placebo	N/A

Detailed Description

We intend to study changes in serum 25(OH)D level with calorie restricted weight loss in obese subjects. This will be a double dummy, placebo controlled randomized trial. Subjects whose serum 25(OH)D level is below 80 nmol/L will be assigned randomly to either the vitamin D supplemented or the placebo group. Those who are assigned to the placebo group will be weighed on a weekly basis and serum 25(OH)D level will be followed every 8 weeks for a minimum of 16 weeks and extended to the duration of weight loss along with serum calcium level. Changes in serum 25(OH)D level will be obtained with weight loss through restricted caloric intake.

To study the 25(OH)D dose-response curve with vitamin D supplementation in obese subjects, vitamin D supplemented group will receive initial daily vitamin D3 supplementation dose based on their baseline serum 25(OH)D level as described in Methods and Procedures section. Serum 25(OH)D levels will be drawn at 8 weeks and adjustments to the dose will be made based on the an algorithm to achieve serum 25(OH)D levels between 80 and 140 nmol/L. The dose-response curve obtained at 8 weeks will be compared to the one already established with non-obese subjects. Serum 25(OH)D level will be obtained at 16 weeks and compared with the data available from non-obese subjects.

Study Design

Study Type:

Interventional

Actual Enrollment :

23 participants

Allocation:

Randomized

Intervention Model:

Parallel Assignment

Masking:

Triple (Participant, Care Provider, Investigator)

Primary Purpose:

Treatment

Official Title:

Vitamin D Supplementation Requirement in Obese Subjects

Study Start Date :

Dec 1, 2008

Actual Primary Completion Date :

Jun 1, 2011

Actual Study Completion Date :

Aug 1, 2011

Arms and Interventions

Arm	Intervention/Treatment
Placebo Comparator: Placebo Half of subjects will be randomized to the placebo group.	Drug: placebo The placebo group will receive sugar pills appearing similar to the vitamin D capsules.
Active Comparator: Vitamin D3 This is the study group that receives Vitamin D supplementation.	Drug: Vitamin D3 Vitamin D supplementation will follow an algorithm for initial vitamin D dosing and for dose changes. Subjects will receive 100 ug/day of vitamin D3 if their 25(OH)D level is less than 50nmol/L and 50 ug/day if their 25(OH)D level is between 50 and 80 ug/day.

Arm

Intervention/Treatment

Placebo Comparator: Placebo

Half of subjects will be randomized to the placebo group.

Drug: placebo

The placebo group will receive sugar pills appearing similar to the vitamin D capsules.

Active Comparator: Vitamin D3

This is the study group that receives Vitamin D supplementation.

Drug: Vitamin D3

Vitamin D supplementation will follow an algorithm for initial vitamin D dosing and for dose changes. Subjects will receive 100 ug/day of vitamin D3 if their 25(OH)D level is less than 50nmol/L and 50 ug/day if their 25(OH)D level is between 50 and 80 ug/day.

Outcome Measures

Primary Outcome Measures

Mean level of 25(OH)D during calorie restricted weight loss from the placebo group. [baseline and at 8 weeks]

Secondary Outcome Measures

Dose response curve (the 'slope' i.e. the ratio of ∆ 25(OH)D/ initial vitamin D3 dose) in vitamin D supplemented group. [8 weeks]

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 65 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Inclusion Criteria:

Healthy men or women between the ages of 18 and 70 years old who are enrolled in our Weight Management Program with baseline BMI > 30 Kg/m2.

Exclusion Criteria:

Pregnancy,
Serum 25(OH)D level greater than 80 nmol/L,
Hypercalcemia (serum calcium level greater than the upper limit of normal),
Recent surgery or illness,
Those with chronic use of medications that influence calcium/vitamin D metabolism such as anti-convulsants, lithium and steroids. Thiazide diuretics for hypertension will be acceptable.
Subjects with sarcoidosis will be excluded.
Those who do not qualify to participate in the Weight Management Program will be excluded. They include subjects with active substance abuse and unstable cardiac disease.

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Winthrop University Hospital	Mineola	New York	United States	11501

Sponsors and Collaborators

Winthrop University Hospital

Investigators

Principal Investigator: John Aloia,, MD, Winthrop-Unviersity Hospital

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

Responsible Party:

Winthrop University Hospital

ClinicalTrials.gov Identifier:

NCT00996866

Other Study ID Numbers:

08028

First Posted:

Oct 16, 2009

Last Update Posted:

Dec 15, 2014

Last Verified:

Dec 1, 2014

Additional relevant MeSH terms:

Vitamin D Deficiency

Vitamin D

Cholecalciferol

Study Results

No Results Posted as of Dec 15, 2014