Osteoporosis is a common condition widely recognized today as a health risk. A good way to determine if your bones have become weak is through a bone density scan. Bone is living tissue and goes through a constant process of renewal. Old bone is torn down and replaced with new bone, keeping the skeleton strong and well tuned and also keeping the body’s balance of minerals such as calcium, which is stored in the bones for use at times when the blood level becomes low.
During childhood, more calcium is deposited into bone than is taken out, and peak bone mass, when bones are thickest and strongest, occurs at about age 35. After that age, bones slowly become less thick, and the loss becomes more noticeable for women after menopause and for men after age 65.
The result is a pattern commonly related with aging, weak appearance, loss of height, low weight and a dowager’s hump or bent appearance. These are sure signs of osteoporosis, but none of these may be present. A broken bone that happens when there is the least amount of stress is commonly the first sign of a problem. But there is no need to wait that long to get a bone density scan and see if you are at risk.
Who? What? When? Where?
Smaller scanners to measure bone density at the ankle are available at Bremo pharmacy. These ankle scanners are a good screening tool to see if someone may be at risk for, or actually have osteoporosis. However, the gold standard for osteoporosis diagnosis is the Dual Energy Absorptiometry (DEXA) scan, which can usually be done in a physician’s office or outpatient clinic in about 15 minutes. With low levels of radiation, DEXA can give measurements of bone mineral density at the hip, spine, wrist and other common sites of fracture and help a doctor decide the course of treatment, if any.
For the patient, DEXA requires no preparation except for not taking a calcium supplement on the day of the exam and not wearing metal buttons or buckles. There is no pain or discomfort, the cost will vary but is usually covered by health insurance when recommended by a physician. Always check with your insurance company before the procedure.
As to who is to be considered for a bone density screening, there is little agreement. The U.S. Preventive Services Task Force in 2002 recommends screening for all women age 65 and over and women aged 60 and over who have risk factors for osteoporosis. Men over 70 were also recommended for screening. The National Osteoporosis Foundation has similar guidelines.
Risk factors include fractures that occur with low impact or because of weakness, a family history of osteoporosis, low body weight (under 125 pounds), smoking, too much alcohol use and use of certain drugs such as steroids and thyroid medication.
The Task Force pointed to risks such as increased anxiety and the chance that results might sway a woman to choose hormone replacement therapy without reason. With recent research showing other serious risks related with hormone therapy, it is no longer as likely.
In practice, many doctors today screen all postmenopausal women on the theory that they are at risk by due to age and hormonal status. As one speaker at an osteoporosis conference put it: bone density screening in older patients is as reasonable as measuring cholesterol.
Persons in the lowest quartile for bone density have a 10-fold greater risk of hip fracture compared to those in the highest quartile. For heart disease, by comparison, the risk increases four-fold from the lowest to the highest quartiles of serum cholesterol.
Recent data from the Study of Osteoporotic Fractures pointed to that even a single measurement of bone density was a good judge of the long-term risk of suffering a fracture.
For postmenopausal women, diagnosis and recommendations for treatment are commonly based on the T-score, a comparison of the person’s bone mineral density against that of a healthy young adult. The World Health Organization defines osteoporosis as a T score of -2.5. Osteopenia, a milder condition, is defined as a T score of -1 to -2.5.
For women who have not passed menopause and men age 65 and younger, the T-score can be misleading. In such cases, doctors use the Z-score, which is a comparison of bone mineral density against an age-matched sample.
Regardless of age, there are steps anyone can and should take to promote strong, healthy bones. The National Osteoporosis Foundation recommends:
- Eating foods rich in calcium and vitamin D. Recent results from the Women’s Health Initiative showed disappointing results for subjects taking calcium and vitamin D supplements, but there is no question that milk; soy products; green, leafy vegetables and other foods help build and maintain bones. For persons over 50, 1,200 milligrams of calcium and 400 to 600 IU (some experts recommend greater amounts of vitamin D) of vitamin D are recommended.
- Getting regular weight-bearing exercise.
- Avoiding smoking and excessive use of alcohol.
- Talking to your doctor about bone health.
- Getting a scan to measure your bone density and, if necessary, taking medication to treat low bone density.
Estrogen replacement no longer leads the list of treatments, although it may still be used for certain people. Other options, approved by the FDA, include: bisphosphonates (alendronate, ibandronate and risedronate), calcitonin and raloxifene, all of which slow or stop the rate of bone loss. Another medication, teriparatide, a form of parathyroid hormone, speeds up new bone formation.
If your bone structure is slowly declining, you should know about it, and a bone density scan will give you the details. By knowing, you can do something that may reduce or eliminate the weakness and anxiety that bother many older men and women.
Kerri Musselman, PharmD—Rev 5/12/10 TNK
