[Diphosphonates in the treatment of osteoporosis]

The efficacy of diphosphonates in the treatment of diseases with increased osteoclastic bone resorption has been clearly demonstrated. Recent results show that these substances are also effective in the treatment of osteoporosis. Intermittent application of the first generation bisphosphonate, etidronate, up to three years is free of risk, stabilizes trabecular bone density after two years and seems to decrease the progression of deformations of the vertebral column in women with postmenopausal osteoporosis and vertebral fractures. In order to prove this benefit clearly, further studies of longer duration are needed. Continuous application of the second generation bisphosphonate, pamidronate, leads to an increased density of vertebral bodies in osteoporotic patients up to four years and a decreased frequency of new vertebral fractures. These results must however still be confirmed by controlled studies with more patients. There are also indications that a continuous treatment with pamidronate is able to prevent the steroid-induced bone loss. There are on the contrary no results about the effect of bisphosphonates on the fracture rate of peripheral bones and only limited results about the use of bisphosphonates in the prevention of postmenopausal bone loss. Before bisphosphonates can be offered as an alternative solution to hormone substitution therapy, we still need extensive studies about efficacy and safety.