Osteoporosis
Am I at Risk?

What is osteoporosis?
Osteoporosis, or "thin" bones, is a disease that gradually weakens bones, making them more fragile and likely to break. It is not a form of arthritis. Osteoporosis leads to an increase in certain types of fractures (broken bones), such as hip fractures, wrist fractures, and compression fractures of the spinal vertebrae (back bones) (Click here or on figure for details). Although it can occur in men or women at any age, this condition most commonly affects women after menopause.

Our bones are dynamic tissues; new bone is constantly growing to replace old bone. The rate of new bone growth changes as we age. Bones grow quickly during childhood and adolescence and thicken during early adulthood. Between ages 25 and 35, our bones reach their maximum thickness, which is considered "peak bone mass." After early adulthood, bones begin to lose mass faster than they can replace it. In women, the rate of bone loss increases as estrogen levels decrease after menopause. Left unchecked, this bone loss can lead to osteoporosis.

Age-related bone loss in men occurs almost as rapidly as in women. However, men develop a greater bone mass while they are growing and do not experience the accelerated phase of bone loss that women have in their early menopausal years. Therefore, osteoporosis generally occurs less frequently in men.

Risk factors
Several factors increase the risk of developing osteoporosis. They include hormonal status, heredity, lifestyle choices, use of certain medications, physical activity level, and associated disease states.

In women, menopause, which can occur naturally or as a result of surgery (removal of ovaries), is the most common risk factor. The chance of developing osteoporosis can be more problematic for women who have an early menopause because they prematurely lose estrogen. Men with a low testosterone level are also at risk for osteoporosis.

You are at increased risk if you have older relatives who have sustained certain fractures (e.g., hip, wrist, and spine), are hunched over, or have lost height because of osteoporosis. Women of all ethnic backgrounds are at risk for developing osteoporosis; however, white and Asian women are at a higher risk than other women are. Thin, petite, small-muscled women are at higher risk than other women are.

Beginning in your late teenage years, lifestyle choices affect the strength of bone and rate of bone loss. For example, alcohol is toxic to bones. Heavy drinking (i.e., more than two alcoholic drinks each day) can cause osteoporosis even if you do not have other risk factors. Smoking reduces bone mass and can interfere with estrogen function. You are at increased risk of developing osteoporosis if your diet has always been low in vitamin D and calcium, which are the substances that help the body build bone. When eaten in large amounts, protein-rich or salty foods may cause your body to lose calcium. Caffeine and certain medications, such as cortisone or excess thyroid hormone, increase calcium loss. (However, do not stop taking any prescribed medication without your doctor's approval.) Inactivity weakens bones. Over time, these weakened bones can become thinner and can break.

Bone loss is associated with a variety of diseases and conditions, such as Paget disease, multiple myeloma, anorexia nervosa, diseases treated with steroids, and malabsorption of calcium or vitamin D. Advanced kidney and liver disease can contribute to an acceleration in osteoporosis. Osteoporosis is a characteristic of several endocrine (glandular) diseases, such as overactivity of the thyroid or parathyroid glands, excess production of growth hormone, Cushing syndrome, and hyperprolactinemia.

Osteoporosis can affect the quality of your life. Talk with your doctor about the factors that may put you at risk for this condition and about what you can do to prevent or treat it.

Clark H. Cobb, M.D.
Columbus, Georgia

For more information, contact the National Osteoporosis Foundation, 1232 22nd St, NW, Washigton DC 20037-1292 or http://www.nof.org