Osteoporosis is a growing problem for women. Biphosphate drugs such as Alendronate have proven effective at increasing bone mineral density by decreasing bone breakdown. In certain clinical situations a 24-hour urinary calcium excretion measurement is recommended to determine the level of calcium supplementation needed by women on drug therapy with alendronate or similar.
A study published this January in the Gynecology and Endocrinology journal investigated the usefulness of a 24-hour urinary calcium. The study attempted to find a correlation between urinary calcium excretion and increase in bone mineral density following one year of treatment with alendronate.
A total of 64 women were enrolled in the study. The women were postmenopausal, had a previous diagnosis of osteoporosis, using HRT (hormone replacement therapy), and were prescribed alendronate for osteoporosis. Bone mineral density was measured at baseline. Women were also taking calcium supplements, but these amounts were not recorded. After one year 24 hour urinary calcium excretion was measured as well as repeat bone mineral density.
The results found no correlation between urinary calcium excretion and change in bone mineral density. Bone mineral density did increase in both the spine and femur after one year of treatment with alendronate. The authors suggest that urinary calcium excretion may be more related to calcium supplementation and dietary intake.
In conclusion, there appears to be no clinical relevance to a 24-hour urinary calcium excretion to determine the level of calcium supplementation for women on biphosphate therapy for osteoporosis.
Posted by Kristopher Foster on March 6, 2006 10:10 AM
