An interventional study of Vitamin D3 and Calcium Citrate (Citracal) in Osteoporosis and Aging, sponsored by Creighton University. Completed at 1 site in United States. Open to female participants aged 57 Years and older. Per ClinicalTrials.gov, last updated 2016-03-14.
Sponsored by Creighton University · Not applicable, Interventional, and Treatment
The purpose of this study is to examine the effects of several doses of vitamin D on hormones related to bone, calcium absorption, bone density and muscle strength.
The prevalence of osteoporosis is high in the United States, with about 10 million people over the age of 50 already having the disease and another 34 million at risk for developing it. Development of low-cost and effective strategies is important for preventing osteoporosis and reducing osteoporotic fractures. A simple inexpensive strategy to prevent osteoporosis is adequate nutrition with calcium and vitamin D. Serum 25OHD (25-hydroxyvitamin D) is now accepted as the objective measure of vitamin D nutrition. There is a growing understanding that serum 25OHD concentrations of at least 30-32 ng/ml are needed for optimal bone health at which serum parathyroid hormone (PTH) concentrations reach a minimum.
There are no systematic prospective dose response studies aimed at determining the optimum amount of vitamin D intake required to maintain optimum serum 25OHD levels in the population which will help in determining the estimated average requirement (EAR) and recommended dietary requirement (RDA) for vitamin D. More work to determine the RDA for vitamin D has been recommended by the Panel on Calcium and Related Nutrients of the Food and Nutrition Board. This study is aimed at filling the information gap by concentrating on the high risk group of postmenopausal women. We are testing the theory that increasing serum 25OHD to a level greater than 30 ng/ml will reduce serum PTH in the high risk group of vitamin D insufficient postmenopausal women with an adequate intake of calcium. We also believe that the dose of vitamin D that will achieve this level is approximately 4400IU per day, which is well above the suggested adequate intake of 400-600 ID recommended for the elderly.
In a one year double blind, randomized prospective clinical trial, we will examine the dose response effect of supplementation with different doses of vitamin D3 (400, 800, 1600, 2400, 3200, 4000, 4800IU/day) on the primary outcomes of serum 25OHD and PTH in 160 postmenopausal Caucasian and 160 African American women who have inadequate vitamin D levels in winter. We expect that the results from this study will add useful and important information about the RDA for vitamin D for postmenopausal women who are more susceptible to osteoporosis. The results from this study will also help in designing future clinical trials to study the effect of vitamin D, for example in preventing fractures, falls, cancer.
The main objective of the current proposal is to study the effect of increasing doses of vitamin D3 in the high risk group of postmenopausal Caucasian and African American women with hypovitaminosis D (serum 25OHD \<20 ng/ml) in winter in presence of sufficient calcium intake, in order to determine the Estimated Average Requirement (EAR) that covers 50% and the Recommended Daily allowance (RDA) covers 97.5% of population for vitamin D. We will use a serum 25OHD concentration equal >30 ng/ml and normalization of serum PTH as indicators of adequacy. We expect that the results from this proposal will add important information helpful in designing future larger clinical trials to determine the recommended dietary allowance (RDA) for vitamin D in other ethnic groups and designing clinical trials on the effect of vitamin D on falls and fractures.
We hypothesize that increasing serum 25OHD to a level greater than 30 ng/ml with vitamin D supplements in 97 percent of the study subjects will reduce serum PTH and bone markers to premenopausal range. We postulate that the RDA of vitamin D that will achieve a serum 25OHD of ≥ 30 ng/ml in 97.5% of women during winter is approximately 4400 IU/d and the EAR dose of vitamin D is between 800-1000 IU.
The specific aims of the proposal are,
Progress: Caucasian enrollment completed July 2008; African American enrollment completed May 2009
1,640 studies on the registry are indexed under Osteoporosis; 212 are open to participants now.
This study's enrollment of 273 is above the median of 95 across 1,133 interventional studies indexed under Osteoporosis.
Browse Osteoporosis studies →Creighton University is the lead sponsor of 126 studies on the registry; 4 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
vitamin D3 400 IU daily
Dietary Supplement: Vitamin D3 · Dietary Supplement: Calcium Citrate (Citracal)
vitamin D3 800 IU daily
Dietary Supplement: Vitamin D3 · Dietary Supplement: Calcium Citrate (Citracal)
vitamin D3 1600 IU daily
Dietary Supplement: Vitamin D3 · Dietary Supplement: Calcium Citrate (Citracal)
vitamin D3 2400 IU daily
Dietary Supplement: Vitamin D3 · Dietary Supplement: Calcium Citrate (Citracal)
vitamin D3 3200 IU daily
Dietary Supplement: Vitamin D3 · Dietary Supplement: Calcium Citrate (Citracal)
vitamin D3 4000 IU daily
Dietary Supplement: Vitamin D3 · Dietary Supplement: Calcium Citrate (Citracal)
vitamin D3 4800 IU daily
Dietary Supplement: Vitamin D3 · Dietary Supplement: Calcium Citrate (Citracal)
matched to vitamin D tablet
Dietary Supplement: Vitamin D3
Orally for one year
Orally for one year; dosage adjusted so that calcium intake is 1200-1400mg daily
Also known as: Citracal
Changes in Serum 25-hydroxyvitamin D (25OHD) and parathyroid hormone (PTH) levels
Time frame: Baseline, 6months,12 months
Calcium absorption
100mg calcium+ calcium45
Time frame: Baseline and 12 months
Serum/urine calcium
Time frame: Baseline and every 3 months
Bone markers
Time frame: Baseline, and 12 months
Bone density
spine,hip,total body,lateral
Time frame: Baseline and 12 months
Muscle strength
leg strength( Cybex),timed up and go,hand grip,chair stand,gait speed,quiet stance,postural stability( biodex),standing balance
Time frame: Baseline,6 months,12 months
Falls
questionnaire
Time frame: Baseline and every 3 months
Pulmonary function studies
FEV1
Time frame: baseline and final test
Genotyping
Time frame: one time
Molecular studies of peripheral leucocytes
Time frame: baseline and final test
Adult Depression Score
questionnaire
Time frame: baseline and 12 months
Physical Activity Scale form ( PASE)
questionnaire
Time frame: baseline,6 months,12 months
sun exposure
sun exposure form and skin color evaluation by a reflective meter (SmartProbe)
Time frame: baseline and every 3 months
Basic metabolic panel
Time frame: baseline and every 3 months
serum 1,25 dihydroxyvitamin D
Time frame: baseline and 12 months
quality of life
questionnaire
Time frame: baseline and 12 months
Plan to share: No
This study is completed, as verified in Mar 2016. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Creighton University