Bone Building Osteoporosis Drugs May be Harmful with Long-Term Use

A new study found that bisphosphonate treatments used to enhance bone density in post-menopausal women may have poor long-term effects. The research shows that women who use the treatments for four or more years have lower bone quality and increased risk of atypical fractures of the femur.

Bisphosphonates are intended to slow or stop bone loss during the bone remodeling cycle, when the body removes and replaces bone tissue. But studies by researchers at the Hospital for Special Surgery (HSS) and Columbia University Medical Center show that these treatments may be fundamentally flawed. The treatment alters the material properties of bone, and it may lessen the mechanical integrity of bone and increase the risk of atypical fractures. The diminishing results of the treatment may be related to bisphosphonates suppressing how the body naturally remodels bone.

Columbia Researchers studied the bone structure of 111 postmenopausal women with osteoporosis, around half of whom had been taking bisphosphonates for the previous four years. Those who were taking the bisphosphonates had increased structural integrity early on, but the trend reversed with long-term treatment.

The study conducted by the HSS involved 21 post-menopausal women treated for femoral fractures, 12 of whom had used bisphosphonate treatment for an average of years 8.5 years beforehand. Researchers analyzed the micro-architecture and material properties from samples of the patients' bone. They found no differences in bone micro-architecture, but noticed reduced bone tissue heterogeneity in the patients who had bisphosphonate treatment.

More research on bisphosphonates is needed, and the treatment will continue to be prescribed. But additional research may confirm a need for more effective treatments for osteoporosis.