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Will doses of vitamin D up to 6000 IU reduce osteoporosis in black women - July 2010

Clinical Trail Vitamin D and Osteoporosis Prevention in Elderly African American Women (NIHD)


This study is not yet open for participant recruitment.

Verified by Winthrop University Hospital, June 2010

First Received: June 28, 2010 No Changes Posted

Sponsor:Winthrop University Hospital
ClinicalTrials.gov Identifier:NCT01153568
!! Purpose
Vitamin D is a hormone that is produced when sunlight is absorbed by the skin. Vitamin D insufficiency has been recognized as a problem in areas where sun exposure is limited, especially in the wintertime. In addition, the more pigmented the skin is, the less capable it is of utilizing sunlight to make vitamin D. Vitamin D plays an important role in helping the body absorb calcium and in building strong bones. It has also been shown to improve muscle function in the elderly. As we get older, our vitamin D levels in the blood go down and this may increase the risk for falls and fractures. If we can improve vitamin D status as we age, we may be able to improve muscle strength and decrease the risk of falls and fractures.
Vitamin DDietary Supplement: Vitamin D 3
Other: placeboPhase III

Study Type:Interventional
Study Design:Allocation: Randomized
Control: Placebo Control
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Prevention
Official Title:Vitamin D and Osteoporosis Prevention in Elderly African American Women: A 4-year Randomized, Double-blind, Placebo-controlled Study to Investigate the Effect of Vitamin D Status in Elderly African American Women

Detailed Description:


The long-term goal of this project is to develop strategies for the prevention of osteoporotic fractures in African Americans. Most intervention studies have excluded African Americans because of the erroneous belief that osteoporosis is not a major health problem in this population. In fact, the incidence rate of hip fracture in blacks is 50% of the rate in whites. Since longevity is increasing in the black population, osteoporotic fractures will become an even greater problem for this ethnic minority in the future. Furthermore, morbidity and mortality from osteoporotic fractures is greater in blacks. The elderly require higher intake of vitamin D to prevent bone loss resulting from secondary hyperparathyroidism. Calcium with sufficient vitamin D supplementation may decrease fractures in elderly white populations as a result of reduction in bone loss and falls (improved physical performance). The only fracture intervention study to include African Americans—the Women's Health Initiative—used an inadequate dose of vitamin D (400 IU), a dose unlikely to achieve the vitamin D status proposed by U.S. experts: serum 25 hydroxyvitamin D 25(OH)D concentration above 75 nmol/L. No calcium/vitamin D intervention studies on fall prevention or physical performance have included African Americans.

As a result of increased skin pigmentation, blacks synthesize less vitamin D from sun exposure. As a result, serum 25(OH)D levels are often in the "insufficient" range. This is accompanied by secondary hyperparathyroidism, but adult blacks have a relative skeletal resistance to PTH, so that they have lower bone turnover. They also have more efficient renal conservation of calcium starting in childhood. Addition of vitamin D3 to a calcium-sufficient African American postmenopausal population does not prevent bone loss. The calcium/vitamin D requirements of black adults may be lower than white adults through midlife. However, the elderly require more vitamin D to produce the higher 25(OH)D levels required to overcome the hyperparathyroidism associated with aging. The skeleton of elderly African Americans appears to be susceptible to the increasing parathyroid hormone levels of old age. Bone loss accelerates and bone turnover markers increase in elderly African Americans just as in whites. The specific aims of this project are to determine if dietary supplementation with calcium/vitamin D will safely reduce bone loss and bone turnover and improve physical performance in elderly African Americans. We will enroll 250 African American women in a four-year vitamin D3 intervention trial where serum 25(OH)D will be maintained at an optimum level above 75 nmol/L. Adequate calcium intake will be ensured. Functional markers of vitamin D including bone density, serum PTH, and bone turnover will be measured. The NIH Conference on Vitamin D and Health in the 21st Century, September 5-6, 2007 concluded that research in this population is a high priority.

Eligibility

Ages Eligible for Study: 70 Years and older
Genders Eligible for Study: Female
Accepts Healthy Volunteers: Yes

Criteria

Inclusion Criteria:

  1. Ambulatory women older than 70 years of age. Self declared as African Americans.
  2. 20 nmol/L < serum 25(OH)D level < 65 nmol/L.
  3. Willingness to take study drug and participate for four years in the trial.
  4. Willingness to refrain from the use of self-administered supplements during the trial.

  • Suspect they will have a hard time finding black women who will be willing to not supplement with vitamin D during the trial

Exclusion Criteria:

  1. Serum 25(OH)D levels ? 20 nmol/L or ? 65 nmol/L.
  2. BMD total hip below - 2.5 standard deviation (using NHANES III adult young white men and women as the point of reference) or history of osteoporotic fracture.
  3. Moderate to severe fracture in one or more vertebrae by Instant Vertebral Assessment on DXA.
  4. Treatment with HRT, SERMS, calcitonin, PTH, androgens, bisphosphonates, phosphate or anabolic steroids during 6 months prior to entry.
  5. Use of systemic corticosteroids (oral or IV) within the last year at an average dose of greater than 5 mg per day of oral prednisone or equivalent for a period of three months or more prior to screening.
  6. Hypercalcemia (serum calcium > 10.6 mg (dl) or history of primary hyperparathyroidism.
  7. History of chronic liver disease, chronic renal insufficiency, Parkinson's, metabolic bone disease, hema-tologic tumors, rheumatologic disease requiring steroids, malabsorption or new diagnosis or active treat-ment of cancer 12 months prior to inclusion.
  8. Use of medications that influence bone metabolism (e.g. anticonvulsants).
  9. Significant deviation from normal in either: history, physical examination or laboratory tests as evaluated by the Principle Investigator. Participants with a history of hypercalciuria, nephrolithiasis and active sarcoidosis will also be excluded.
  10. Participation in another investigational trial 30 days prior to screening.
  11. Spinal disease that affects interpretation of bone densitometry like scoliosis with a Cobb angle greater than 15o, history of surgery at lumbosacral spine.
  12. Bilateral hip replacement.
  13. Currently smoking more than 10 cigarettes daily.
  14. Body width on DXA > 25 cm.

Patients who are deemed unsafe to perform muscular function testing as evaluated by the investigator.

------ Study participants should live close to the study site, as this study requires multiple visits over a four year period.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01153568

Contacts

Contact: Jane S. Greensher, R.N. CCRC516 663 2772[email protected]
Contact: Catherine B New516 663 3380[email protected]


Locations
United States, New York
Winthrop University Hospital
Mineola, New York, United States, 11501

Sponsors and Collaborators

Winthrop University Hospital

Principal Investigator:John F. Aloia, MDWinthrop University Hospital

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