Serum vitamin D metabolites in younger and elderly postmenopausal women

Summary Previous investigations have suggested that a lower-than-normal serum 1,25(OH)₂D is found in elderly women with postmenopausal osteoporosis. We examined the fundamental aspects of this theory by investigating serum vitamin D metabolites infour representative samples of Caucasian women. These included 44 early postmenopausal women divided intotwo subgroups: fast bone losers, that is, bone loss>3%/year (n=20), and “physiological” bone loss (n=24); and 28 70-year-old women divided intotwo subgroups: with and without osteoporotic fractures. Serum 1,25(OH)₂D concentrations were virtually the same in all groups thus contradicting the previous reports of low 1,25(OH)₂D in elderly women. Furthermore, mean 25OHD and 24,25(OH)₂D did not differ between the groups. We conclude that 1,25(OH)₂D is unlikely to be significant in the development or treatment of a majority of women with postmenopausal osteoporosis.