COVID-19 is an emerging, rapidly evolving situation.
Get the latest public health information from CDC:

Get the latest research information from NIH:
Working… Menu

Vitamin D Retrospective Study and Role With Disease

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT01798030
Recruitment Status : Active, not recruiting
First Posted : February 25, 2013
Last Update Posted : May 18, 2020
Information provided by (Responsible Party):
Alice S. Ryan, PhD, Baltimore VA Medical Center

Brief Summary:
Vitamin D deficiency is associated with a heightened risk for developing type 2 diabetes, hypertension, and osteopenia/osteoporosis. Vitamin D is made in the skin when it is exposed to sunlight and it is also obtained from the diet and dietary supplements. Older people, individuals with high skin pigmentation, obese and sedentary individuals have low levels of Vitamin D because pigmentation blocks Vitamin D production in the skin, aging and physical inactivity are associated with reduced exposure to sunlight, and obesity is associated with the storage of Vitamin D in fat preventing its utilization by muscle, bone and other tissues that require its metabolic action. These conditions are also associated with heightened risk for developing type 2 diabetes, glucose intolerance, hypertension, and osteopenia/osteoporosis in older and obese individuals. This is particularly heightened in older women who tend to have increased body fat, are more physically inactive and are at high risk for central obesity and its metabolic consequences of diabetes, hypertension and osteoporosis.

Condition or disease Intervention/treatment
Vitamin D Status Glucose Tolerance Blood Pressure Bone Mineral Density Hyperlipidemia Other: Vitamin D

Detailed Description:

The heightened prevalence of obesity in aging especially in postmenopausal women suggests that interventions to raise Vitamin D levels might be preventive of these diseases. Investigators have completed studies of the effects of weight loss and exercise interventions in approximately 400 older women and men over the last 15 years, many of whom are obese. Investigators have data on glucose tolerance, blood pressure and bone density in these studies and stored plasma in which investigators can analyze Vitamin D levels. Vitamin D may be an important risk factor for these metabolic diseases and the availability of these samples for Vitamin D analysis will allow investigators to perform a cross-sectional study to address relationships of Vitamin D levels to glucose intolerance and diabetes, hypertension/blood pressure status, bone mineral density, the degree of obesity, and physical activity status measured as maximal aerobic capacity and accelerometry in these older men and women.

The results of this study have the potential to impact clinical practice in the prevention and treatment of diabetes, hypertension, and osteopenia/osteoporosis. This would circumvent the current dilemma for prevention of these chronic diseases through treatment of obesity, as these data would provide immediate prospects for changing the recommended doses of Vitamin D beneficial for reducing risk for these diseases.

The purpose of this study is to 1) determine the prevalence of Vitamin D deficiency in obese, older men and postmenopausal women and 2) the association of Vitamin D levels to glucose tolerance, blood pressure, bone mineral density, and hyperlipidemia, as well as association with Vitamin D receptor gene polymorphisms affecting metabolic responses to Vitamin D.

Layout table for study information
Study Type : Observational
Actual Enrollment : 362 participants
Observational Model: Other
Time Perspective: Retrospective
Official Title: Association of Vitamin D With Diabetes, Osteoporosis and Cardiovascular Risk
Study Start Date : November 2009
Estimated Primary Completion Date : November 2020
Estimated Study Completion Date : December 2020

Resource links provided by the National Library of Medicine

Drug Information available for: Vitamin D

Group/Cohort Intervention/treatment
Vitamin D
Specimen analysis
Other: Vitamin D
N/A, frozen specimen study

Primary Outcome Measures :
  1. Vitamin D [ Time Frame: Day 1 ]
    Vitamin D level ng/dl

Other Outcome Measures:
  1. IGF-1 [ Time Frame: Day 1 ]
    Insulin like growth factor

  2. IGF binding proteins [ Time Frame: Day 1 ]
    Insulin Growth Factor Binding protein levels

  3. PTH [ Time Frame: Day 1 ]
    Parathyroid Hormone levels

Biospecimen Retention:   Samples With DNA
Vitamin D, IGF-1, and PTH levels will be measured in coded plasma samples belonging to the PI and collaborating Investigators within the GRECC that are stored in our freezers (from previously approved studies: HP-00040261,HP-00040975, HP-00041166 and HP-00041199) . The Nutrition Obesity research center genetics core will determine Vitamin D receptor polymorphisms on de-identified samples. No clinical information will accompany the samples.

Information from the National Library of Medicine

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, Learn About Clinical Studies.

Layout table for eligibility information
Ages Eligible for Study:   45 Years to 85 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population
obese, older men and postmenopausal women

Inclusion Criteria: 45-85 years of age

Exclusion Criteria: none


Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT01798030

Layout table for location information
United States, Maryland
Baltimore VAMC
Baltimore, Maryland, United States, 21201
Sponsors and Collaborators
Baltimore VA Medical Center
Layout table for investigator information
Principal Investigator: Alice S Ryan, PhD Baltimore VAMC
Publications automatically indexed to this study by Identifier (NCT Number):
Layout table for additonal information
Responsible Party: Alice S. Ryan, PhD, Professor, Baltimore VA Medical Center Identifier: NCT01798030    
Other Study ID Numbers: 43973
First Posted: February 25, 2013    Key Record Dates
Last Update Posted: May 18, 2020
Last Verified: May 2020
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No
Keywords provided by Alice S. Ryan, PhD, Baltimore VA Medical Center:
Vitamin D
Cardiovascular Risk
Additional relevant MeSH terms:
Layout table for MeSH terms
Metabolic Diseases
Lipid Metabolism Disorders
Vitamin D
Growth Substances
Physiological Effects of Drugs
Bone Density Conservation Agents