Effective medicines now available to combat osteoporosis

March 1, 2006

In the United States today, 10 million people have osteoporosis (bone density that's about 25% less than a healthy young adult). In addition, 34 million more people have low levels of bone mass, placing them at increased risk. Osteoporosis is responsible for more than 1.5 million fractures annually, including 300,000 hip fractures, approximately 700,000 vertebral fractures, 250,000 wrist fractures, and more than 300,000 other fractures. About 68% of those affected by osteoporosis are women.

The best way to prevent this disease is a comprehensive approach that includes diet, weight-bearing exercise, limited alcohol consumption and no smoking. In addition, bone density testing and appropriate medications are used as needed.

SEVERAL MEDICATIONS TARGET OSTEOPOROSIS

Bisphosphonates can cause heartburn, esophageal irritation, abdominal pain and other gastrointestinal effects. To ensure proper absorption, they must be taken after an overnight fast, in an upright position, and then the patient must remain upright for 30 minutes. "The bisphosphonates have been shown to be effective in preventing fractures in postmenopausal women with osteoporosis, and they all appear to be relatively safe," says Mark Abramowicz, MD, editor of The Medical Letter on Drugs and Therapeutics, a non-profit newsletter that critically appraises drugs. "Weekly or monthly doses have been as effective as daily doses. In the future, bisphosphonate injections at intervals as long as a year may prove to be effective alternatives."

Evista (raloxifene) is a selective estrogen receptor modulator (SERM), which means it has been developed to provide the beneficial effects of estrogens without some of their disadvantages. Evista increases bone mass and reduces the risk of spine fractures, although there is no evidence yet to show that it can reduce the risk of hip and other non-spine fractures. In addition, it appears to substantially decrease the risk of estrogen-dependent breast cancer. Side effects include hot flashes and leg cramps, and Evista leads to a small increase in the risk of deep vein thrombosis and pulmonary embolism.

Calcitonin, available under the brand names Miacalcin, Calcimar and Fortical, is a peptide hormone approved by the FDA for treatment, but not prevention, of osteoporosis. It is taken intranasally, or as a subcutaneous injection. In addition to decreasing bone resorption, it also may have a pain-relieving effect.

A recently approved medication, Forteo (teriparatide, a form of parathyroid hormone) is the first osteoporosis medication that increases the rate of bone formation in the bone remodeling cycle. In one study, women who received daily injections of Forteo for 21 months had a decreased incidence of vertebral fractures (4.5% in the study group compared with 14% in the placebo group).

"We've made enormous progress in osteoporosis treatment," says Felicia Cosman, MD, clinical director of the National Osteoporosis Foundation. "Over the last decade, we've seen the advent of at least six new therapies for osteoporosis, and they're all effective. Obviously treatment needs to be individualized."

Selecting the preferred medication for a particular patient depends on many factors, including age, family history, underlying diseases, how low bone density is, and whether there are any fractures.

"For most people, we start with the bisphosphonates because those medications have the strongest evidence for actually preventing fractures," says Fred Heidrich, MD, a faculty physician in the family practice residency of Group Health Cooperative, a staff model health plan. "Their side-effect profile is quite good in selected candidates, but you can't give bisphosphonates to someone who has low calcium or bad kidneys."