Deciding whether you need a bisphosphonate should start by determining your risk of osteoporosis. You and your doctor should consider such factors as your age, race, and family and medical history. He or she should also arrange for a test called a DXA scan, which will, by using a pencil-thin x-ray beam, measure bone density at your hips, spine, and possibly your wrists.
The DXA score is compared with the average score of 30-year-old women. The comparison, called a T-score, is expressed as standard deviations (SD) from that average. The lower the score, the higher the fracture risk. A T-score of minus 2.5 SD or less defines osteoporosis, while a score between minus 1 and minus 2.5 SD is considered osteopenia. To make diagnoses more standard, the World Health Organization recently developed a calculator that uses those and other risk factors, plus the DXA results, to predict a person's 10-year probability of having a fracture. Known as FRAX, the online tool is available here, and is expected to shift treatment toward those who really need it.
But not everyone requires the test. Consumer Reports medical advisers say that women should have their bone density measured at age 65, men at 70. Postmenopausal women under that age and men 50 and older should be screened if they:
- Are unusually thin or smoke.
- Have had a fracture from a minor trauma, or have a parent who had an osteoporosis-related fracture.
- Have a disease (thyroid or parathyroid disorders, celiac disease, adrenal hyperactivity) or regularly take a medication, such as steroids or certain antiseizure drugs, that causes bone loss.
People who learn from the test that they have osteopenia often only need to take the nondrug steps to strengthen their bones and prevent falls. The case for bisphosphonates is stronger for people with outright osteoporosis or a history of fractures, but even they should balance the risks and benefits.
If you do opt for a drug, it generally makes sense to consider starting with generic alendronate since it's significantly less expensive. And talk with your doctor about the steps you can take to reduce your risk of side effects. If you've taken a bisphosphonate for five years or more, ask your doctor about stopping temporarily to encourage normal bone remodeling and to reduce the risk of side effects.
Bottom line. Bisphosphonates offer only modest benefits in building bone and preventing fractures, and that should be considered along with the risks. Before you start taking one, some of the questions to ask your doctor include:
- Do you think I need to have my bone density measured and if so, why?
- Do you think I need a drug or will supplemental calcium, vitamin D, and nondrug measures suffice?
- If I do take a bisphosphonate, which one do you think would be best for me, and why?
- What are the most common side effects and what can I do to minimize them?
- What are my risks if I do not take medication for this condition?