Osteoporosis drugs prevent common fractures but can raise the risk of ‘atypical’ breaks

Osteoporosis drugs known as bisphosphonates have pros and cons that should be carefully considered by doctors and their patients, according to a new study assessing their impact.

The medications, which include the brands Fosamax and Reclast, clearly reduce the risk of typical fractures caused by osteoporosis such as breaks in the hip and spine. However, the new study clarifies recent findings that the drugs increase the risk of other types of fractures. These so-called “atypical” fractures occur in the femur and in the bone just below the hip joint.

Canadian researchers examined 205,466 women age 68 and older with osteoporosis who took a bisphosphonate for several years and identified 716 women who had an atypical fracture. When compared with a control group of 3,580 women who had not taken bisphosphonates, the long-term use of the drugs was linked to 2.7 times higher odds of hospitalization for an atypical fracture. Overall, in women with five or more years of bisphosphonate use, an atypical fracture occurred in 0.13% of them in the subsequent year.

The study, published Tuesday in the Journal of the American Medical Assn., also showed that use of bisphosphonates for five or more years was linked to a 24% reduced risk of typical fractures compared with sporadic or short-term use of the drugs.

While the risk of atypical fracture is low, the findings “highlight the need for a thoughtful assessment of individual risk of fracture,” the authors wrote. “[L]ong-term use of these drugs may warrant reconsideration, especially in patients at relatively low risk of fracture.” The authors also recommended that patients consider taking a “drug holiday” after five years of bisphosphonate use. However, bisphosphonates are still considered valuable therapy in the appropriate patients, they said.

Related: Doctors suggest that women hit pause button on osteoporosis drugs

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