Bone density and osteoporosis

Bone density testing is a medical test used to determine bone density or strength. These tests can identify if you have low bone density or osteoporosis, and the risk of future bone fractures. The test is simple, comfortable and easy to arrange at an imaging/X-ray site. No other test can provide the same information.

As we age we lose bone mass. Osteoporosis is a disease that causes the skeleton to weaken from loss of bone mass. Osteoporosis is called a “silent disease” because it progresses without symptoms until a fracture occurs. Fractures resulting from osteoporosis most commonly occur in the hip, spine, and wrist, and can be permanently disabling.

Osteoporosis affects both women and men. According to Osteoporosis Australia, over 1 million people in Australia have osteoporosis.

Both men and women may have certain ‘risk factors’ that can make them more likely to develop osteoporosis. People should discuss risk factors with their doctor, and anyone over 50 with risk factors may need a bone check up with a bone density scan. General risk factors can include:

  • Family history: Bone health can be strongly inherited so it is important to note if anyone in your family (particularly parents or siblings) has ever been diagnosed with osteoporosis
  • Low calcium and vitamin D intake
  • Medical history: Certain conditions and medications can have an impact on bone health
  • Corticosteroids - commonly used for asthma, rheumatoid arthritis and other inflammatory conditions o Glucocorticoids (steriods)
    • Low hormone levels
    • Thyroid conditions - over active thyroid or parathyroid
    • Conditions leading to malabsorption eg: coeliac disease, inflammatory bowel disease
    • Some chronic diseases eg: rheumatoid arthritis, chronic liver or kidney disease
    • Some medicines for breast cancer, prostate cancer, epilepsy and some antidepressants
  • Lifestyle factors, such as low levels of physical activity, smoking, excessive alcohol intake, weight (thin body build or excessive weight)

To preserve bone health, both men and women are advised to:

  • Avoid smoking
  • Reduce alcohol intake
  • Increase your level of physical activity
  • Ensure a daily calcium intake that is adequate for your age
  • Ensure an adequate intake of vitamin D

Women

Women are at a greater risk of developing osteoporosis because of the rapid decline in oestrogen levels during menopause. When oestrogen levels decrease, bones lose calcium and other minerals at a much faster rate. As a result a bone loss of approximately 2% per year occurs for several years after menopause.

Treatments for breast cancer that decrease estrogen levels even further can add to the risk of osteoporosis and breaks. To find out more about breast cancer treatments and osteoporosis, read this factsheet from Osteoporosis Australia.

Men

Men also lose bone as they age, however testosterone levels in men decline more gradually so their bone mass remains adequate till later in life. By age 65 or 70 years men are losing bone mass at the same rate as women. The male hormone testosterone helps maintain strong bones, so low testosterone levels can increase your risk of developing osteoporosis and breaking a bone. Certain medications, like therapy for prostate cancer (eg: androgen deprivation therapy), can affect testosterone levels. Men with testosterone deficiency or low testosterone levels can improve their bone density with testosterone replacement.

For more information, go to the Osteoporosis Australia site.