NCT00949832

Vitamin D and Genetics in Nutritional Rickets

• Status: Completed
• Phase: Phase 4
• Study type: Interventional
• Enrollment: 109 (actual)
• Sponsor: Mayo Clinic · Academic / Other
• Sex: All
• Age: 6 Months – 16 Years
• Healthy volunteers: Accepted

Summary

The purpose of this study is: 1. To compare the response of rickets to calcium with and without vitamin D. 2. To assess whether vitamin D increases calcium absorption in calcium deficiency rickets. 3. To compare the response of children with and without rickets to orally administered vitamin D3 and vitamin D2 4. To identify mutations that influence calcium and vitamin D metabolism among families of children with rickets in Nigeria and Bangladesh. 5. To assess the functional status of the 25-hydroxylase enzyme in families possessing a 25-hydroxylase mutation.

Detailed description

Previous studies of Nigerian children with rickets demonstrated the superiority of calcium over vitamin D in producing healing. It is not known whether the addition of vitamin D to calcium will produce a better response to treatment than calcium alone in Nigerian children. A previous study suggested the possibility that vitamin D may augment the effect of calcium. We will compare the response of rickets to calcium with and without vitamin D. In addition, very little human data clearly demonstrates the effect of supplemental vitamin D on calcium absorption. We will assess whether oral vitamin D increases the already high calcium absorption even further. Recent published data indicate that the increase in serum 25-hydroxyvitamin D may be more sustained with vitamin D3 than with vitamin D2. We will compare the response of Nigerian children with and without rickets to orally administered vitamin D3 and vitamin D2. Because nutritional rickets tends to run in families, we will also examine amplified DNA for evidence of mutations that influence calcium and vitamin D metabolism among families of children with rickets in Nigeria and Bangladesh. Families possessing a recently identified 25-hydroxylase mutation will be given oral vitamin D2 and vitamin D3 to determine the functional status of the 25-hydroxylase enzyme.

Conditions

• Nutritional Rickets

Interventions

Type	Name	Description
DIETARY_SUPPLEMENT	Vitamin D + Calcium	Vitamin D 50,000 IU orally once monthly for 6 months; Calcium carbonate (as powdered limestone) 500 mg orally twice daily for 6 months
DIETARY_SUPPLEMENT	Calcium	Calcium carbonate (as powdered limestone) 500 mg orally twice daily for 6 months; Vitamin B complex (used as placebo) 1 tablet monthly for 6 months
DIETARY_SUPPLEMENT	Vitamin D2	50,000 IU given orally once
DIETARY_SUPPLEMENT	Vitamin D3	Vitamin D3 50,000 IU given orally once

Timeline

• Start date: 2004-01-01
• Primary completion: 2007-04-01
• Completion: 2007-04-01
• First posted: 2009-07-30
• Last updated: 2012-07-04

Locations

1 site across 1 country: Nigeria