Breast cancer survivors have high risk of fracture

Postmenopausal women who have survived breast cancer have a heightened risk of fractures, according to the results of a new study. Given the growing size of this patient population, the investigators say, strategies are urgently needed to reduce this risk.

The findings, published in the Archives of Internal Medicine, are based on an evaluation of nearly 5,300 breast cancer survivors who were enrolled in the Women's Health Initiative Observational Study. These women were compared with 80,848 women with no cancer history. All of the subjects were followed for about 5 years.

After accounting for potential risk factors, such as age, weight, ethnicity, and geographic region, breast cancer survivors were 31 percent more likely to sustain a fracture than controls were, Dr. Zhao Chen, from the University of Arizona in Tucson, and colleagues report.

Having a history of breast cancer raised the risk of fractures at all body sites, except the hip. However, the increased risk of vertebral fractures was statistically significant only for breast cancer survivors diagnosed before 55 years of age.

After accounting factors including medication use, hormone levels and the presence of other illnesses, the heightened fracture risk seen in breast cancer survivors fell to 15 percent, the investigators point out.

Still, "the excess number of fractures may be as high as 13,000 per year for the 2 million postmenopausal breast cancer survivors in the US," the authors note.

"Clearly," they say, "more research is needed to understand the fracture risk in this special population and to develop more strategies to reduce the number of fractures among breast cancer survivors."

SOURCE: Archives of Internal Medicine, March 14, 2005.