Drug for Brittle Bones May Cause Heart Condition

Osteoporosis is a common disease that typically affects post-menopausal women, though it can weaken the bones of both genders at any age. The presence of osteoporosis can be unnerving, as even the slightest mishap can mean a broken bone. While drugs have been developed to help combat this condition, it has been found that one drug prescribed for osteoporosis might cause heart problems.

The drug in question is Fosamax, a very popular medication prescribed to nearly 10 million men and women for osteoporosis, and one that is said to increase bone strength and reduce incidents like hip fractures by 63 percent. Fosamax is a bisphosphonate manufactured by Merck, approved by the U.S. Food and Drug Administration (FDA) in 1995. (Generic versions of the drug were approved in February of 2008 by the FDA.)

A new study conducted by Seattle-based Group Health and the University of Washington has determined that women taking Fosamax are twice as likely to become afflicted with a chronically irregular heartbeat as those not taking the drug. The results of the study, which were led by Dr. Susan Heckbert, professor of epidemiology and researcher at the Cardiovascular Health Research Unit of the University of Washington, were published in the April 28th issue of the Archives of Internal Medicine.

Research was conducted on more than 700 female Group Health patients, studied over the course of the three-year period. The irregular heartbeat, medically known as atrial fibrillation, was present in all of the women. Those women were compared to over 900 women who did not have the condition. In total, 6.5 percent of the women with atrial fibrillation took Fosamax, and 4.1 percent without the heart condition took the drug.

The findings noted that women who used the drug inherent in Fosomax-alendronate-had an 86 percent higher risk of having atrial fibrillation as compared to women who never used any kind of bisphosphonate. After taking into consideration the medical history of patients with cardiovascular disease, the researchers concluded that 3% of atrial fibrillation incidents could be directly related to the use of alendronate.

The National Osteoporosis Foundation let it be known that they would like to see more data to further research any correlation between irregular heartbeats and the use of Fosamax. Other medical professionals have also noted that the findings of the recent study will need to be confirmed by further studies in order to have any impact on the prescription recommendations of Fosamax by doctors.

Since an irregular heartbeat is not a fatal condition, the danger of atrial fibrillation might be considered inconsequential when compared to the drug's positive effects on the bones and the subsequent reduction of bone fracture possibilities. Atrial fibrillation most commonly causes palpitations, fainting, or fatigue but is usually not life threatening, as nearly 9 in 100 people over the age of 80 have an irregular heartbeat.

However, women at great risk for or a history of heart failure, diabetes, or other types of heart disease may want to refrain from taking Fosamax. And in some cases, atrial fibrillation can cause blood clots that lead to strokes, though many with the condition can be treated with a blood thinner as a precaution.

This is not the first time Fosamax has come under some scrutiny and been studied for its safety in patients. Several years ago, a study published in the Journal of Oral and Maxillofacial Surgeons stated that there was a connection between Fosamax and osteonecrosis of the jaw (ONJ), which keeps jawbones from healing after routine dental surgery and in some cases, the bones can rot and die. As a result of an outcry from the public and medical organizations, the FDA and Merck issued warnings to health care professionals in 2004.