Bisphosphonates Linked To Atrial Fibrillation Risk in New Study

Bone-strengthening drugs like Fosamax and Actonel may increase the risk of atrial fibrillation, according to the findings of new research.  

In a study published online by the American Journal of Cardiology on March 15, researchers from Maimonides Medical Center in New York indicate that they found a significant increase in the risk of atrial fibrillation among individuals taking medications known as bisphosphonates.

Researchers conducted a meta-analysis of nine studies involving 135,347 subjects. They found that intravenous bisphosphonates, such as Zometa and Aredia, were linked to a 40% increased risk of atrial fibrilliation, while medications given in oral form, such as Fosamax and Actonel, were linked to a 22% increased risk.

This is not the first time scientists have examined the possibility of a link between atrial fibrillation and Fosamax. In 2008, the FDA dismissed such links after reviewing data from a study that only involved 19,687 patients taking a bisphosphonate and 18,358 taking placebos.

In this latest study, researchers indicated that it may be time for the FDA to take a second look at the potential risk of atrial fibrillation from bisphophonates.

Fosamax Bone Fracture Side Effects

Fosamax (alendronate sodium) is one of the most widely used oral bisphosphonate medications, which was introduced by Merck in 1995 for treatment and prevention of osteoporosis. Before it became available as a generic in 2008, Fosamax generated over $3 billion in annual sales and was used by millions of Americans.

Merck currently faces more than 4,000 Fosamax femur fracture lawsuits filed by former users throughout the United States, which all include similar allegations that the drug maker failed to provide adequate warnings for consumers or the medical community about the risk of atypical fractures.

Most of the lawsuits over Fosamax have been filed since late 2010, when the FDA required Merck to add new warnings about the risk of bone fractures.  These warnings provided new information for consumers and the medical community about the importance of identifying symptoms of new hip or groin pain, which could occur before an atypical fracture of the femur.

The complaints allege that Merck knew or should have known about these risks long before the warnings were provided, and claim that if adequate information had been provided to users and the medical community plaintiffs could have avoided suffering complete fractures on Fosamax by avoiding the medication or stopping use earlier.