Long-Term Use of Osteoporosis Drug May Increase Fracture Risk

Several recent studies have investigated fracture risk in people who have been taking a specific type of osteoporosis medication for more than four years.  The drug, called bisphosphonates, sold under the trade names Fosamax, Boniva, Actonel, and others, may not be best used for lengthy periods of time.

Two studies were presented at this month's American Academy of Orthopaedic Surgeons Annual Meeting in New Orleans.  These studies both found that while these drugs may help prevent fracture and increase bone for several years, their long-term use should be re-evaluated.  The concern is that over time, the bisphosphonate medications may cause the bone to become more brittle, and prone to specific types of fractures.  One specific fracture that has been linked to long-term use of bisphosphonates is a spiral femur fracture, or a fracture of the thigh bone.

The image to the right is of an elderly woman who had been diagnosed with osteoporosis after a hip fracture about a decade ago.  The patient has been treated with three screws to fix her hip fracture (see the top of the image), and placed on a bisphosphonate medication to treat her thinning bone.  Recently, she twisted her leg while turning in her house, and felt a crack in her thigh and fell to the ground.  The x-ray shows a new fracture in the shaft of the thigh bone (femur).  It is this type of unusual injury that may become more likely in individuals taking bisphosphonates for many years.

Does this mean that bisphosphonates are bad?  Absolutely not!  In fact, they are one of the best tools to help fight osteoporosis.  Furthermore, these studies are small investigations, and may not truely reflect a problem with long-term use of bisphosphonate medications. However, bisphosphonates may be best used for a finate time period, and then other medications may be better.  Trying to better understand how bisphosphonate medications change bone strength over time is the goal of current research.  As we learn more about bisphosphonates, more specific recommendations may be forthcoming.  For now, if you have been recommended to take bisphosphonate medications, discuss this with your doctor.  If you have been on these medications for more than four years, it may be worthwhile to discuss the long-term implications of these drugs, and whether or not you should be switched to another osteoporosis medication.

Addendum (3/18/2010): The Food and Drug Administration (FDA) has issued a statement regarding the concerns of unusual femur fractures reported in patients taking oral bisphophonate medications for lengthy time periods.  They state that at this time, there is no clear connection between oral bisphosphonates and subtrochanteric femur fractures.  Furthermore, the National Osteoporosis Foundation finds that the benefits of these medications outweigh the risk of these unusual complications.  For more information, read the statement from the National Osteoporosis Foundation.

Related: All About Osteoporosis | Osteoporosis Drugs | Bone Density Testing

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_{"Long-Term Use of Osteoporosis Drugs Linked to Fractures" Business Week, March 11, 2010.}

_{Image © Jonathan Cluett, M.D.}