Osteopenia: What You Should Know

By Jeanne Faulkner

Reviewed by QualityHealth's Medical Advisory Board

We hear a lot about osteoporosis-the big name in bone loss disease; but not so much about its predecessor, osteopenia. Like osteoporosis, osteopenia means there's a decrease in the amount of calcium and phosphorus in bones. Decreased calcification, bone density, or bone mass is caused by inadequate osteoid (bone making cells) synthesis. When bones lose density, they become weak and brittle and break more easily.

What differentiates osteopenia from osteoporosis? Osteopenia is a less severe form of bone loss than osteoporosis as determined by a bone mineral density (BMD) test.

How do you know if you're at risk for osteopenia? The best way to tell is by having a BMD test. BMD testing is an enhanced type of x-ray called dual-energy x-ray absorptiometry (DXA or DEXA).

The National Osteoporosis Foundation explains:

A BMD test uses a special machine to measure bone density. Some people also call it a bone mass measurement test. This test lets you know the amount of bone mineral you have in a certain area of bone. Bone density testing can be done on different bones of your body, including your hip, spine, forearm, wrist, finger or heel. A BMD test is safe and painless, and provides important information about your bone health. Your healthcare provider uses this information to make recommendations to help you protect your bones.

BMD test results indicate a number called a T-score, which tells whether your bone density measurements are above or below average. The World Health Organization explains what the T-Score means:

A T-score between +1 and -1 is normal bone density. Examples are 0.8, 0.2 and -0.5.

A T-score between -1 and -2.5 indicates low bone density or osteopenia. Examples are -1.2, -1.6 and -2.1.

A T-score of -2.5 or lower is a diagnosis of osteoporosis. Examples are T-scores of -2.8, -3.3 and -3.9.

Since low T-scores are common in older adults, doctors also look at the Z-score results (which compares what's normal for someone your age and body size) in younger people. They also consider other risk factors for low bone mineral density:

Age. Bones can become less dense with age in both men and women due to decreased hormone production (which assists osteoids in making bone cells), less exercise and sometimes, decreased food intake.
Tobacco use. Smoking weakens bones.
Alcohol use. Drinking more than 2 drinks of alcohol a day can have a damaging effect on your bones.
Low body weight. Studies have associated it with low bone density.
Race. White women are at 2 to 3 times greater risk than men or black and Hispanic women.
Previous fractures. Especially of the hip and spine.
Certain medications. Particular ones include corticosteroids and aromatase inhibitors used for breast cancer.
Certain medical conditions. This includes stroke, rheumatoid arthritis, diabetes, and Parkinson disease.
Sedentary lifestyle. Since exercise helps build strong bones, people who don't exercise are at risk for low bone density.