Rationale for active vitamin D analog therapy in senile osteoporosis

PTH is a potent endogenous stimulator of bone resorption, and PTH secretion increases with age (i.e., secondary hyperparathyroidism). Accordingly, secondary hyperparathyroidism may contribute to the pathogenesis of senile osteoporosis. We postulate that there is a subgroup of elderly subjects who have elevated serum PTH because of 1,25(OH)2D3 deficiency/resistance or both. We believe that with appropriate vitamin D therapy (vitamin D, 1,25(OH)2D3 or 1α(OH)D3) and adequate calcium, much of the problem associated with secondary hyperparathyroidism seen in the senile osteoporotic patient can be effectively treated.