Among the meds in question are the oral drugs Fosamax, Actonel and Boniva and the intravenous drug Reclast. Boniva also comes in IV form.
Bisphosphonates also have been linked to osteonecrosis of the jaw, in which the bone loses blood supply, weakens and dies. Studies show the problem most often occurs with invasive dental procedures in some patients taking intravenous bisphosphonates for osteoporosis or in cancer patients given bisphosphonates to alleviate bone pain. Intravenous bisphosphonates reduce the common gastro-intestinal (GI) problems used with the oral drugs.
In late November, the American Dental Association approved a recommendation that doctors refer patients to their dentist before starting them on bisphosphonates.Issues surrounding the drugs are important ones because they are prescribed to many people. According to the Medical Expenditure Panel Survey, as reported in the American Journal of Health-System Pharmacy in 2009, 5.6 million Americans in 2005, the most recent year data is available, were prescribed osteoporosis drug treatment, up from 2.3 million in 1999.
While the controversy has garnered the attention of consumers, doctors, the FDA and drug manufacturers, one local orthopedic surgeon says the focus may be misdirected in the search for a solution. Another osteoporosis treatment, a drug made by Eli Lilly but which insurers fail to cover, could remedy problems linked or potentially linked to bisphosphonates.
So why would drugs used to prevent bone loss possibly be connected to spontaneous breaks in the body's strongest bone or in the jaw? One has to understand how the body creates bone and how the drugs work, says orthopedic surgeon Dr. David Almdale with Fort Wayne Orthopaedics.Bone is active tissue, its cells continually working in sync to regenerate new bone and break down old bone via the osteoblasts and osteoclasts.
Bisphosphonates affect the osteoclasts, preventing bone breakdown and re-absorption. While this increases bone density, the delicate balance between osteoblasts and osteoclasts is disturbed. What happens, Almdale says, is that, over time in some people, the old bone becomes brittle and susceptible to fractures.
Almdale compares the drugs' effect on bones to the difference between fine china and Corelle dishes.
“The china is heavier and denser but shatters more easily,” he said. “The Corelle is made to have some give in it.”
Almdale points out that use of bisphosphonates in people with osteoporosis has indisputably reduced the number of hip fractures by 40 percent, and even more for the spine. Bisphosphonates have improved quality of life and reduced pain and hospitalizations. Now, however, Almdale says of the drugs, “We have to see (them) in a smarter fashion.”He is recommending patients take a one-year holiday from the drugs after five years of usage. Regular bone mass density scans as well as kidney function tests and checks of mineral and hormone levels are also recommended.
An improved option for patients with moderate to severe osteoporosis is the Lilly drug Forteo, Almdale says. Forteo has fewer GI side effects and less stringent dosing parameters compared to oral bisphosphonates, which must be taken on an empty stomach with a full glass of water, and the patient must remain upright for at least an hour.
Once-a-day, self-injected Forteo “helps form new bone,” Almdale says, noting the drug is similar to a portion of parathyroid hormone and acts to stimulate more bone activity in both osteoblasts and osteoclasts.
The down side? Forteo, approved by the FDA in 2002, is very expensive, costing $7,000 or more a year. But Almdale points out hospital costs for patients with broken hips are greater. The average U.S. hospital cost for hip surgery was $30,000 in 2006, according to the Agency for Health Care Research and Quality. That doesn't include rehabilitation.
“I've argued and argued on behalf of patients who would benefit from this drug,” Almdale says.
In some states where insurers are convinced it is the better option, Forteo is covered. Studies of the drug showed it decreased spinal fractures by 65 percent and other fractures by 53 percent, according to the FDA. Fosamax, one of the oral bisphosphonates, showed a decrease in spine fracture by 49 percent and hip fracture by 56 percent compared with a placebo in a separate study.Forteo is prescribed for two years only. In lab animals, high doses of the drug were associated with increased incidence of bone cancer, which led the FDA to give the drug a black box warning. But according to the FDA, as of 2006, with more than 250,000 prescriptions for the drug written, a single human case of bone cancer was reported in a patient taking Forteo. The rate of bone cancer in the general population is four cases per one million people, according to the National Cancer Institute.
As with hormone replacement therapy, women today are challenged to do their homework and discuss risks versus benefits of osteoporosis drugs with their doctor. Will Forteo become a more commonly used drug? Cost may be the determining factor. The outcomes of additional research on bisphosphonates could also be a deciding factor.
Meanwhile, as the future of osteoporosis treatment unfolds, reduce your risk by:
* Getting adequate calcium in your diet.
* Increase vitamin D intake (discuss recommended levels with your doctor or nutritionist).
* Do regular weight-bearing exercise.
* Minimize caffeine and alcohol intake.* Do you know your T score and your Z score? After a bone mass density scan, doctors use these scores to help them diagnose osteoporosis. For more information, check out the National Osteoporosis Foundation at www.nof.org/
* Do you know osteoporosis risk factors? Check out the list at www.nof.org/