Effect of vitamin D and calcium supplementation on bone turnover in institutionalized adults with Down's Syndrome.

Objective: To assess the status of vitamin D and the effects of calcium and vitamin D3 supplementation on the bone metabolism in a group of adults with Down's syndrome (DS).

Design: Randomized, parallel, controlled and open clinical trial.

Setting: Institution for mentally handicapped: Fundación Uliazpi, Diputación Foral de Guipúzcoa, San Sebastián, Spain.

Subjects: A total of 23 persons with DS, residents at the Uliazpi Foundation were recruited and all completed the study.

Intervention: In all, 12 participants were randomly allocated to receive 1 g of calcium and 800 IU of vitamin D once daily for 1 year while 11 were assigned to the control group, receiving no supplementation.

Results: We found no differences between groups regarding serum calcium and phosphorous levels. The remaining parameters showed differences between the two groups consistent with a beneficial effect of the intervention: serum levels of parathyroid hormone, osteocalcin and crosslaps diminished while serum 25 OH vitamin D3 level increased.

Conclusions: The results obtained allow to include people with DS as a risk group with regards to vitamin D deficit, which that can be corrected with vitamin D and calcium supplementation, and giving rise to an improvement of the biochemical markers related to the phospho-calcium metabolism and bone remodelling.