News June 2006 Issue

When It’s Time To Treat Bone Loss

Bone loss, an integral part of aging, can increase your risk for osteoporosis. The good news is it can be treated and sometimes reversed.

Just like taxes, bone loss is a fact of life, a condition that everyone will eventually face. While many Americans over the age of 50 have experienced bone loss—10 million have osteoporosis and another 34 million are at risk for developing this common bone disease—most people are unaware that they’re losing bone and that the condition can and should be treated.

Men and women lose bone differently, at different rates and at different sites in the body, with each often  needing different types of treatment. But bone loss begins in both often from early adulthood, with women losing more than 50 percent (and men approximately 40 percent) of bone density in their hip over a lifetime, according to John Carey, M.D., staff physician with The Cleveland Clinic’s department of rheumatic and immunologic diseases. Accelerated bone loss may be seen in many circumstances, such as menopause, glucocorticoid therapy, rheumatoid arthritis, and a host of other illnesses.

“The decision to treat bone loss depends on several factors—the rate and amount of loss and, most importantly, the individual’s risk of fracture,” says Dr. Carey. “The best way to assess bone loss is by measuring bone-mineral density.”

Measuring density predicts risk
The gold-standard test for noninvasive measurement of bone density, as well as diagnosing osteoporosis in individuals without fragility factors, is the Dual Energy X-ray Absorptiometry (DXA) scan. A DXA scan uses low doses of radiation to measure the amount of bone mineral content in the spine, hip, and occasionally the forearm. A safe, simple, pain-free test, a DXA scan is recommended for all women age 65 and older and for women at risk who are under age 65.

While women generally experience more bone loss than men, men still account for approximately 25 percent of all osteoporotic fractures and 20 percent of hip fractures, making an osteoporosis assessment an integral part of their overall health care as well. Men should be tested if they have factors that increase their risk of bone loss, including a family history of osteoporosis or low testosterone levels.

“In order to prove that bone loss has occurred, a DXA scan must be completed twice over a period of time—generally after two years, but after six to 12 months for patients who may experience rapid bone loss, such as those starting or taking glucocoricoid therapy (steroids, prednisone, etc.),” says Dr. Carey. “Bone density is measured in grams-per-centimeter squared, and the computer part of the bone density scanner also calculates a T-score using this information, which compares your bone density to a young, healthy adult. In 1994, the World Health Organization designated a T-score higher than -1 as normal, -1 to -2.4 as indicating low bone mass, and -2.5 or less as osteoporosis.

Figures 1-3 show stages of osteoporosis and bone density loss.

“Osteoporosis,” adds Dr. Carey, “can be diagnosed in any person who has a history of fragility fracture, regardless of their T-score.”

Although the primary causes of bone loss are age and menopause, the risk increases substantially in patients being treated for cancer with corticosteroids—regardless of sex—and in patients suffering from other disorders, such as rheumatoid arthritis. An older patient, with no risk factors for osteoporosis other than family history, may have a bone density loss of 1-2 percent per year, while patients who are taking steroids may lose 10-20 percent of their bone mass in six months, substantially increasing the risk of fractures, even if they have a normal T-score.

“Guidelines for the treatment and prevention of osteoporosis are generally based on the actual T-score, rather than actual bone loss. Even if significant bone loss is not been demonstrated by serial DXA scans,” says Dr. Carey, “we generally treat all patients who are at significant risk for bone loss and osteoporosis, to prevent the fractures it can cause.”

Building healthy bones
Like any other condition, the best treatment for bone loss depends on the individual, and a multidisciplinary approach works best. While lifestyle changes, such as stopping smoking and adequate calcium and vitamin D, are beneficial for everyone, women who are perimenopausal or postmenopausal may also be treated with hormone-replacement therapy or other medications. Studies show that that 50 percent of North American men and women are vitamin D deficient in the winter, and additional vitamin D may be necessary.

Exercise is also important in building healthy bones. Weight-bearing exercise, such as walking, can increase bone strength, prevent bone loss, and help with balance to prevent falls.

Medication advances  
“Older patients who are at a higher risk of fracture are often treated with medications called bisphosphonates, such as alendronate (Fosamax) or risedronate (Actonel). These have been shown to prevent bone loss in both men and women and all three types of fracture—vertebral, non-vertebral, and hip fracture,” says Dr. Carey. “For those who can’t tolerate these drugs due to side effects such as nausea or abdominal pain, we can use other FDA-approved drugs, such as teriparatide (Forteo), ibandronate (Boniva), raloxifene (Evista), and calcitonin (Mialcalcin). Teriparatide is particularly interesting because it actually helps build bone, rather than than prevent bone loss. The downside is that it requires daily injection for two years.

“Advances in medication are making the treatment and reversal of bone loss a reality, and the best treatment for an individual’s bone loss may vary by patient,” says Dr. Carey. “But it’s important that bone loss  be detected and treated early in both men and women who are at risk for osteoporosis.”