Effects of two 1-year calcium and vitamin D3 treatments on bone remodeling markers and femoral bone density in elderly women

The aim of this study was to compare the effects of a 1-year treatment with calcium and vitamin D3 combined in a tablet (Orocal®) with the effects of a reference treatment of calcium administered in a sachet (Ostram®) and vitamin D3 as a tablet (Devaron®) on bone remodeling markers and bone mineral density (BMD) in elderly women. The study population comprised 119 women ⩾70 years of age, 80% of whom were institutionalized. The women were randomly allocated to receive treatment for 1 year with elemental calcium 0.5 g and vitamin D3 400 IU combined in one chewable tablet taken twice daily (group 1) or elemental calcium 0.6 g (1 sachet) and vitamin D3 400 IU (1 chewable tablet) taken twice daily (group 2). BMD of the proximal femur was measured at four sites before and after the 1-year treatment period; serum 1–84 intact parathyroid hormone (PTH) concentration, serum 25-hydroxyvitamin D3 (25[OH]D3) concentration, and bone alkaline phosphatase activity were measured at baseline and after 6 and 12 months of treatment. At month 12, BMD had increased at all sites in patients in group 1; the increase was statistically significant at the trochanter (2.34%). In group 2, BMD had increased slightly at the femoral neck and decreased slightly at the other sites, without any statistically significant differences. BMD changes were not statistically different between the two groups except at the trochanter, where we observed a 2.34% increase in group 1 versus a 0.32% decrease in group 2. In group 1, PTH decreased significantly from baseline to month 6 (13%) and then did not change significantly from month 6 to month 12. In group 2 the decrease was not statistically significant. In addition, 25(OH)D3 increased significantly in the two groups from baseline to month 6 (group 1, 107%; group 2, 96%). This significant increase continued but became less marked from month 6 to month 12 (13% and 15%, respectively). Bone alkaline phosphatase values decreased significantly in both groups from baseline to month 6; however, this decrease was significantly greater in group 1 (35%) than in group 2 (22%). From month 6 to month 12, values remained constant in both groups. In this study, results with the calcium and vitamin D3 combination tablet were comparable to those of the separated calcium and vitamin D3 supplementation concerning parameters involved in senile osteoporosis. Densitometric data showed some prevention of age-related bone loss; biochemical data showed the correction of vitamin D3 deficiency and the reduction of PTH secretion, both of which are responsible for increased bone remodeling in the elderly. The results of this study confirm those of previous studies on the effects of calcium and vitamin D3 supplementation in institutionalized elderly patients.