Vitamin D metabolites – relation to age, menopause and endometriosis

We investigated the influence of menopause, age and sex on vitamin D metabolism in a large group of healthy women (n = 113) and men (n = 108) and in a group of early postmenopausal women (n = 124). Furthermore, we studied the vitamin D metabolism in 42 women with endometriosis. The vitamin D metabolites did not show dependence on age or on duration of menopause. The serum concentrations of vitamin D metabolites did not differ in normal men and women. There were highly significant seasonal oscillations for 25(OH)D and 24,25(OH)2D3 but not for 1,25(OH)2D. Women with endometriosis had significantly elevated serum 1,25(OH)2D compared to the normal women. Our study indicates that ageing is not associated with a significant depletion of 25(OH)D, 24,25(OH)2D or 1,25(OH)2D in normal men and women up to the age of 75 years. Furthermore, changes in vitamin D metabolism seem not to be an important factor in early postmenopausal bone loss. Our results on patients with endometriosis indicate that these patients may have some calcium-metabolic disturbances.