The bisphosphonates: risks and benefits of long term use

Bisphosphonates are widely used globally as the main treatment for osteoporosis. Both safety and efficacy have only been rigorously evaluated in studies of relatively short duration (3-5 years), with smaller extension studies. The evidence for benefit beyond five years in intervention studies is limited and does not include proven efficacy against nonvertebral fractures. Observational studies suggest a sustained benefit against hip fractures. Bisphosphonates are stored in the skeleton for months to years, depending on the degree of bone turnover and the binding properties of the bisphosphonate in question. The effects of continued treatment on bone strength is not known but there are concerns that osteonecrosis of the jaw and atypical femur fractures may stem from long term bisphosphonate use.

► Bisphosphonates have cumulative effects and release from the skeleton is slow. ► Little data on the long term benefits and harms of bisphosphonate treatment. ► Treatment beyond 5 years may prevent vertebral fractures in high risk patients. ► Skeletal complications could arise from long term bisphosphonate use. ► Optimum duration of treatment probably depends on patient risk factor profile.