Popular drugs for osteoporosis appear to pose a risk for unusual fractures. Bisphosphonates such as Actonel, alendronate, Boniva, Fosamax and Reclast have been promoted to prevent hip and spine fractures in people with weakened bones. A new study suggests, however, that such drugs may also increase the risk of unusual femur fractures. In these cases, the thigh bone breaks straight across like a piece of chalk. This can happen when person is walking. The only advance warning may be aches in the thigh.
Swiss researchers analyzed data on people with such atypical fractures. They found that the longer the patients had taken bisphosphonates, the higher their risk for these rare but serious breaks. Those who took these medications for over five years had more than 100 times the risk of an atypical femur fracture. The absolute risk remains very low, and an accompanying editorial recommends that doctors continue to prescribe bisphosphonates for people with osteoporosis. A recent warning from the FDA suggests that these drugs may need to be reevaluated after three to five years of use.
[Archives of Internal Medicine, online, May 21, 2012]