Osteopenia is a condition involving low bone mass. This means that a person’s bones are not as strong as they should be and may be more likely to break. A person with osteopenia has slightly less dense bones than expected, but their condition may be not severe enough that they are considered to have osteoporosis. If you graded them on a report card, healthy bones would get an A, bones with osteopenia a B or C and bones with osteoporosis a D or an F.
Causes and Risk Factors of Osteopenia
Osteopenia has two causes. The first is a failure to reach one’s peak bone mass, which is the maximum amount of bone a person is genetically programmed to build in her lifetime. Peak bone mass is typically reached by age 20 in men and age 30 in women. The second cause is a loss of bone once a person has reached peak bone mass. Certain diseases that prevent calcium from being absorbed into the bones, including celiac disease, inflammatory bowel disease and eating disorders, may keep young people from reaching their peak bone mass. Genetic factors, like a predisposition to osteoporosis, can also leave someone with relatively low bone density. Also, some medications and lifestyle habits, such as smoking or drinking too much alcohol, can negatively affect bone mass accrual.
On the other end of the spectrum is someone who has a healthy amount of bone mass but loses it. This tends to happen with aging, especially for women during menopause, when they lose estrogen. Osteopenia in these women may hit a nadir before the bone loss reaches osteoporosis.
Symptoms of Osteopenia
Osteopenia and osteoporosis do not cause pain or movement issues on their own. This makes it challenging to know if someone has either condition. A common symptom is height loss. Most people lose an average of one inch of height as they age (from peak adult height), but losing more than this may be the first clue that there is an underlying bone quality issue.
Fractures or broken bones are the biggest indicator that there may be a skeletal bone abnormality. If an adult over age 50 falls from a standing height and breaks a bone, a bone density test should be done to screen for osteopenia and osteoporosis. Even those with osteopenia can be at risk for fractures.
The best way to diagnose osteopenia is with a bone density test. This test uses low energy x-rays to see the calcium content of a person’s bones and compare it to that of both healthy young adults (t-score) and people of the same age and sex (z-score). Most commonly, bone density tests examine the lumbar spine, hips and wrist.
Prevention and Treatment of Osteopenia
It isn’t possible to completely prevent osteopenia. Some people are genetically predisposed to have low bone density. But even for them, exercising and getting enough dietary calcium during the childhood, adolescent and young adult years is important. For women, ensuring they are menstruating regularly is a significant sign that they make enough estrogen, which is a hormone vital to good bone health. Avoiding cigarettes and limiting alcohol is also essential for building and maintaining strong bones.
Once people pass the age at which they reach peak bone mass, about 20 for men and 30 for women, a healthy, calcium-rich diet is still important. Weight-bearing exercises such as running, walking and weightlifting can also help maintain bone and muscle strength.
Even if you can’t prevent osteopenia, you may be able to stop it from turning into osteoporosis. Staying active and doing weight-bearing exercise is key. Hormone therapy within 10 years of the final menstrual period has been clinically proven to prevent osteoporosis and reduce fracture risk. In fact, the use of hormone therapy strictly for bone health and osteoporosis prevention is FDA-approved.
Follow-up bone density testing can also help to ensure osteopenia is being managed appropriately. If a bone density test shows osteopenia, the test should be repeated in two years (if not sooner) to monitor for changes and allow for intervention before the situation deteriorates too far.
Treatment for osteopenia depends on the person. The first step is to determine if the individual is at a high risk for fracture, in which case certain bone health medications are used to prevent bone breakdown and build the skeleton back up as much as possible.
For all people with osteopenia, eating foods rich in calcium is important, including certain dairy products, dark green leafy vegetables and some fish. Vitamin D is also crucial but is harder to get from the diet. A vitamin D supplement can help.
Dr. Jessica Starr is an endocrinologist at HSS, with particular interests in women’s reproductive health, bone health and the impact of type 2 diabetes on the skeleton. She is board certified in both endocrinology and internal medicine. Dr. Starr received her undergraduate degree from Cornell University in Ithaca, NY and her medical degree from the Albert Einstein College of Medicine of Yeshiva University.