Osteoporosis

Osteoporosis, breast cancer and cardiovascular disease are the three most serious conditions affecting U.S. women. One in four women will develop osteoporosis and nearly 50% of all women over the age of 50 will sustain an osteoporosis related fracture. The disease currently affects more than 20 million individuals in this country accounting for about 1.5 million fractures annually, most commonly of the spine and hip. Of women with hip fractures, 20% will die within one year of the injury and 50% of the survivors never walk independently again. Osteoporosis represents a major national financial burden of ten billion dollars annually. Despite these ominous statistics, this disease can be prevented and even treated to some degree. Osteoporosis is an illness in which bone loss is responsible for the bones becoming fragile and thus resulting in fractures, back pain, loss of height, and curvature of the spine. Normally, bone mass in women increases in early life and reaches a maximum peak mass by age 35. Men have higher peak bone mass than women do which accounts for the lower instance of the problem in older men. A slow loss of bone mass begins after age 35 and continues throughout life essentially asymptomatically. Bone loss is most pronounced during the first three to four years after menopause at an annual rate of 2.5%. Thereafter the rate falls to just under 1% each year for the ramainder of the woman's life.

The most common risk factors are postmenopausal status, Caucasian or Asian race, positive family history, short stature/small bones, thinness, low calcium intake, sedentary lifestyle, never having had children, history of abnormal thyroid/parathyroid function, history of smoking, history of anorexia, alcohol abuse.

Lifelong adequate calcium intake maximizes peak adult bone mass and lowers the risk of osteoporosis. Thus beginning with our daughters, we should encourage adequate calcium intake. In the postmenopausal woman, a calcium intake of 1500 mg per day is recommended. Calcium rich foods include: dairy products (obviously), but also leafy green vegetables, and fish, particularly those with bones (sardines). Calcium supplements are available in various forms. They can be taken with meals in divided doses or simply once at night. Extremely excessive calcium intake can however predispose one to kidney stones.

Exercise is a potent initiator of bone remodeling and thus bone health. However, this exercise must be weight-bearing (walking, running, aerobics, step class). Although swimming and biking are excellent forms of cardiovascular physical fitness they are not adequate for preservation of bone.

In the past the only medication that was effective for prevention of bone loss and osteoporosis in postmenopausal women was estrogen replacement therapy. Many women however cannot, should not, or will not consider hormone replacement therapy for a variety of valid and complex reasons. Thus for these women, in the past, measurement of bone mineral density was unnecessary since regardless of the outcome of the test not treatment was available. Most recently a new category of drugs called bisphosphomates have become available. The best known and most widely used of these is called Fasomax. It is not hormomal and it can actually increase bone mineral density in women with osteoporosis. More recently, the drug has been approved for use in prevention of osteoporosis.

The most efficient way of measuring bone mineral density is known as DEXA (Dual Energy X-ray Absorptiometry). This gives an amount of radiation exposure similar to dental x-rays. It is performed on both the hip and spine, taking about ten minutes for each site. The results will either be indicative of normal bone mass, low bone mass(known as osteopenia), or actual osteoporosis depending on the levels the test indicates. In the future, biochemical markers that can follow formation of new bone for patients on therapy as well as monitor reabsorption and loss of further bone may become helpful. These however do not diagnose osteoporosis.

Thus, from this brief summary you can see that recently there have been great changes in the dagnosis of, treatment of, and understanding of osteoporosis. Feel free to share this information with your friends, family or colleagues. Ask Dr. Goldstein for more information about bone mineral densitometry (BMD) test.

©2004 Steven R. Goldstein, M.D.