Fosamax and other osteoporosis drugs in the same class that are taken by millions of women around the world can lead to bone necrosis, a painful and disfiguring condition that results in bone death, Canadian researchers has warned. A study conducted by scientists at the University of British Columbia (UBC) and McGill University found that bisphosphonates tripled the risk of developing bone necrosis. The study was is the largest ever to look into the connection between bone necrosis and specific brands of bisphosphonates, sold under the names of Didrocal, Actonel, and Fosamax. Today’s warning follows a recent alert from the U.S. Food and Drug Administration (FDA) about bisphosphonates and their link to a higher possibility of severe and sometimes incapacitating bone, joint, and muscle pain in patients who are taking that class of drugs.
“I think the study’s important just basically to let the public know if they do experience any severe, unusual pain they could tell their health professional,” said Dr. Mahyar Etminan, the principle investigator from the University of British Columbia.
The incidence of bone necrosis is rare, diagnosed in about one in 20,000 people a year, but it is serious and extremely painful and does lead to permanent loss of the blood supply to the bones. Without blood, the bone tissue dies and causes the bone to collapse. If necrosis involves the bones near a joint, it often leads to collapse of the joint surface. What happens is, “The drugs basically hang around in bone for a long period of time and cut off blood supply to the bone, which eventually dies off and becomes necrotic,” Etminan explained.
The recent study was collaboration between UBC, The Vancouver Coastal Health Research Institute, and McGill University in Montreal and was based on the health records of 88,000 Quebec residents over a period of seven years. The team decided to take on the research after academic papers began linking necrosis of the jaw with the use of bisphosphonates. Etminan said the study allows patients and their doctors to look at the positives and negatives of taking this class of medication.
Meanwhile, use of bisphosphonates medications such as Didrocal, Actonel, and Fosamax has increased as the population has aged. Etminan said that use will likely further increase due to a possible link between estrogen use and breast cancer, prompting women to switch from estrogen therapy to bisphosphonate therapy to stop bone fractures from occurring. The drugs like Didrocal, Actonel, and Fosamax are also becoming easier to take, with once-a-month and once-a-year doses now available.
“Our study’s take-home message is that you know if you experience severe pain, it may not be because of your osteoarthritis or even osteoporosis and just check it out and make sure it’s nothing serious,” he said.
The disease primarily affects the shoulders, knees, and hips at the joints. Etminan said therapy for bone necrosis ranges from non-invasive treatments such as taking anti-inflammatories to invasive surgery involving total joint replacement, depending on the seriousness of the condition.