Fluorides and bisphosphonates in the treatment of osteoporosis

The therapeutic aim in osteoporosis to maintain or increase bone mass can be achieved by inhibition of osteoclastic resorption (antiresorptive treatment), stimulation of osteoblastic formation (anabolic treatment), or a combination of both strategies. Antiresorptive therapy of osteoporosis with the nitrogen-containing bisphosphonates alendronate and risedronate is regarded today as evidence-based medicine. A significant reduction in the number of patients with new vertebral fractures has been documented already after 1 year. Anabolic therapy with fluoride was studied less extensively. The low price of fluoride salts and the lack of a patent protection may have contributed to this deficit in large studies. However, several recent medium-sized trials with a low-dose fluoride regimen consistently show a continuous increase in bone density and also a decrease in the rate of new fracture events. In our own pilot study with intermittent etidronate/fluoride therapy, we found significantly additive effects on bone mineral density. A larger trial with this therapeutic strategy using fractures as the primary endpoint would be of great interest.