About 18 million Americans have osteopenia. Osteopenia refers to early signs of bone loss that can turn into osteoporosis. With osteopenia, bone mineral density is lower than normal. However, it is not yet low enough to be considered osteoporosis.
Not everyone who has osteopenia develops osteoporosis with its painful, debilitating fractures. But osteopenia can turn into osteoporosis if it is not diagnosed early and promptly treated. Osteoporosis can result in easily fractured bones and other very serious bone problems. It can also cause disfigurement and lead to loss of mobility and independence.
A bone density scan can detect thinning bones at an early stage. If you already have osteoporosis, bone scans can also tell you how fast the disease is progressing.
But an abnormal bone scan can create as many questions as it answers. Who should get a bone density scan, and what do the results mean? If your bone density is below normal, what can you expect, and what should you do?
Bone health is measured in two ways. The first is bone density. Bone density defines the thickness of your bone. The second is bone mass. Bone mass means how much bone you have. Bone mass, or the amount of bone you have, usually peaks around age 30. Then bone mass begins to decline. Your body starts to reabsorb bone faster than new bone can be made.
To find bone density, your doctor measures the levels of minerals in your bones. These minerals include:
The denser the content of your bone mineral is, the stronger your bones are.
With aging, your body absorbs back calcium and other minerals from your bones. This reabsorption can make your bones weaker and lead to osteopenia and osteoporosis. The bones become more vulnerable to fractures and other damage.
What Are Some Risk Factors for Osteopenia and Osteoporosis?
Risk factors for developing osteopenia are the same as those for developing osteoporosis. They include:
How Can my Doctor Test for Osteopenia and Osteoporosis?
The most accurate way to diagnose osteopenia and osteoporosis is through bone mineral density testing. This is usually done with a dual-energy X-ray absorptiometry (DEXA) scan.
DEXA scan results are reported as T-scores:
Normal bone: T-score above -1
Osteopenia: T-score between -1 and -2.5
Osteoporosis: T-score below -2.5
Other tests can be done to help diagnose osteoporosis and osteopenia. Quantitative ultrasound is one such test. It measures the speed of sound in the bone to assess bone density and strength. DEXA scans are usually still needed to confirm results from ultrasound and other tests.
Experts advise that you receive regular bone density scans in these cases:
You are a woman 65 or older.
You are a woman 60 or older with certain risk factors. Low body weight is considered the most important risk factor.
There are no clear guidelines for when to begin screening for women between 60 and 65 who have no other risk factors. Nor are there specific guidelines for women under 60 who have additional risk factors. That's why it's important to work with your doctor to determine a screening plan to meet your needs.