If you're one of the millions of people confused about bone density screenings, you're not alone. Many women and men ask themselves the same thing every year. Is it age related? Does it mean I have osteoporosis? What exactly is my bone density and how do I read the results?
Your bones are actually living and growing tissue and are made of three components that make them strong:
- Collagen, a protein that gives bones a flexible framework
- Calcium-phosphate mineral complexes that make bones hard and strong
- Living bone cells that remove and replace weakened sections of bone
Typically you make more bone than you lose until sometime between the ages of 18 and 25, when you reach peak bone mass. According to the National Osteoporosis Foundation, the more bone you have at the time of peak bone mass (density), the less likely you are to break a bone or get osteoporosis later in life. But as we age, we tend to lose more bone mass than we form. And it speeds up once we hit middle age. Menopause has a big impact on bone loss in women, when our estrogen levels drop.
What happens with bone loss?
Osteoporosis occurs when you lose too much bone, or make too little, or both. Your bones become porous, weaken and can leave you at risk of fractures or broken bones.
Osteoporosis can be considered a silent disease; people can't feel their bones getting weaker and it's revealed once an accident happens or they break a bone. Women are more likely to have osteoporotic fractures because our bones are smaller and we lose bone mass faster through hormonal changes around the time of menopause.
How many people have osteoporosis?
About 54 million people are affected by osteoporosis and bone loss. And, some studies suggest that 1 in 2 women and 1 in 4 men, age 50 and older, will break a bone because of osteoporosis. Risk factors to consider for osteoporosis include:
- Being over age 50
- Female and having gone through menopause
- Breaking a bone
- Having rheumatoid arthritis
- Having a parent who broke a hip
- Having low Vitamin D levels
- Taking certain medications, such as steroids or proton pump inhibitors
- Consuming tobacco or alcohol (more than 2 drinks a day for women)
What is a bone density scan?
A bone density scan, also called a Dexa or DXA, is a way to measure the strength of your bones and your chances of breaking a bone. It's a low-dose X-ray that takes about 10 minutes and can be done without disrobing. Most often it's performed on the lower spine and hips.
Do I need a bone scan if I'm under 65?
Most people younger than 65 don't need a DXA scan unless they're at increased risk of a fracture as determined by the World Health Organization's (WHO) 10 year Fracture Risk Assessment Tool (FRAX). If your risk is equal to or greater than that of a 65-year-old woman (9.3% as determined by FRAX), then a DXA is recommended. Your doctor can help you calculate your fracture risk (FRAX).
So then, who should get a bone density scan?
Women should get a bone scan beginning at age 65. Men age 70 and older may want to talk with their doctors before deciding. Younger women and men should consider the test if they have risk factors for serious bone loss as indicated by the FRAX risk assessment.
How can I prevent and treat osteoporosis?
There are ways to prevent and treat weak bones to stave off osteoporosis! The universal recommendations for bone health are the same throughout our lives despite our bone density. These include consuming a healthy diet with adequate calcium, daily exercise and assuring we have sufficient Vitamin D. If your DXA scan results indicate you're at high risk of fracture, medications can be considered.
How to read your test
The radiologist will review the DXA scan and the radiology report includes clear language stating whether your bone mineral density is normal, osteopenic or osteoporotic as well as follow-up recommendations. DXA scans and mammograms are often performed at the same facilities and can usually be done during the same visit. Always talk to your primary care physician if you have questions and be sure to get your DXA if recommended.