The good and the not-so-good of osteoporosis drugs

- North Island Midweek

08/18/2009 - “Do you treat osteoporosis?” asked Patty. “I have been doing some research and I sure want to avoid the Fosamax that my doctor has prescribed for me.”

Patty, 65, had recently read an article about the bisphosphonates, the drugs that are used to treat osteoporosis. These include Fosamax, Actonel and Didrocal.

The most notable things she remembered from the article were the increased risk of jaw necrosis (death of the jaw bone), increased risk of esophageal cancer and atrial fibrillation.

I explained to Patty how these drugs worked. The normal physiology of bone causes it to be continually broken down by osteoclasts and rebuilt and remodeled by osteoblasts, and in this process it becomes stronger.

If you remove the rebuilding and remodeling step, the bone on a DEXA scan looks more dense and hard, but is the bone stronger? Bisphosphonates inhibit the breakdown or resorption of bone which slows the loss of bone mineral density, but they also inhibit the rebuilding and remodeling step as well. These drugs do not stabilize estrogen or progesterone nor do they restore calcium levels in the bone.

Certainly the research shows that these bisphosphonates reduce the risk of vertebral, hip and other non-vertebral fractures in women with osteoporosis, at least in the short run.

Their use has been growing since the Women’s Health Initiative results scared women away from estrogen replacement which, until then, had been the leading conventional method of preventing osteoporosis. The big question is what are the long-term effects of using these drugs?

Most women who start taking bisphosphonates could easily be taking them for 25-30 years. Trials lasting longer than 10 years are raising some doubts about their long-term safety and efficacy.

In one case report, a physician, age 59, who had been taking Fosamax for seven years told about the spontaneous fracture of her femur while riding a subway. The subway car jolted and her femur shattered.

Keeping on the Fosamax at the advice of her doctors, her fractures refused to heal despite aggressive treatment for nine months such as bone stimulation and two implant surgeries. Finally, on her own, she halted the Fosamax and within six months the broken bones began to unite.

Her story is not unique and a small number of studies are emerging where men and women are experiencing low-impact atypical fractures associated with the long-term use of bisphosphonates, with the most common fracture being the upper femur. This is one of the strongest bones in the body and fractures are usually as a result of major, high-energy trauma.

The most common side effect of the bisphosphonates are local irritation of the esophagus. Usually, taking the drug exactly as prescribed prevents this symptom. but for some the drug is discontinued because of this side effect.

Jaw necrosis occurs in four percent of users and atrial fibrillation in 2.5-3 percent and are more recent, yet disturbing side effects that are surfacing.

Another concern is that these drugs remain locked in the bones for many years, long after they are discontinued, with a half life of up to 10 years, possibly contributing to jaw necrosis after a minor trauma such as a tooth extraction.

What can you do? Bisphosphonate therapy for osteoporosis clearly increases bone mineral density over the first five years of its use. Dr. Ott, in his editorial in the Clinical Endocrinology and Metabolism in 2005, suggests their use should stop after five years.

I explained to Patty there are agents such as progesterone, testosterone and strontium that stimulate remodeling or osteoblastic phase of bone therefore increasing bone density.

I have seen many DEXA (bone density) scans improve over the years when patients maintain on a comprehensive nutritional program specific for osteoporosis. In fact, the technicians are often surprised at the improvement when they find out that the patients are not taking the bisphosphonates.

Dr. Ingrid Pincott, naturopathic physician, has been practicing since 1985 and can be reached at 250-286-3655 or www.DrPincott.com