Unfortunately, there’s no one-size-fits-all answer. The National Osteoporosis Foundation recommends that all women 65 and over get a bone density test once. Bone loss is typically so slow that repeating a bone density test more often than every two years is not necessary. Most insurers, including Medicare, will pay for testing every two years.

Assessing a woman’s risk for more rapid bone loss is too complex for blanket recommendations, said Dr. Robert Neer [cq], director of the Osteoporosis Center at Massachusetts General Hospital in an email. And some women – as well as some men – need a bone density X-ray test to look for signs of bone thinning even before age 65 if they have certain medical problems,

People who need earlier or more frequent testing include women with early menopause (before age 42) and men with androgen deficiency, because both these hormonal conditions can lead to bone-thinning. Anyone who gets a fracture after minimal trauma and people with rheumatoid arthritis should also ask their doctors about earlier or more frequent testing. So should people who take cortisone or prednisone, which can adversely affect the bone, and people with sprue or cystic fibrosis or inflammatory bowel disease.

The trouble is, it can be tough to get insurance coverage for earlier or more frequent testing. In theory, Medicare will pay for more frequent testing when it’s “medically necessary.” But in nearly all cases, Medicare does “not accept a letter from a physician as proof of medical necessity,” said Neer. This makes it difficult to assess whether a newly-prescribed medication has stopped bone loss, he added. Medicare has also reduced its payments for the bone X-rays and plans to do so again next year. “As a result, many small providers have stopped or will stop performing bone density tests,” said Neer.

Even so, it makes sense to ask your doctor about bone density testing even before age 65 if you think you are at higher-than-normal risk of osteoporosis.

Osteopenia is not a disease but a warning sign that you have lower than normal bone density, which can raise the risk of fractures somewhat and develop over time into osteoporosis, says Dr. Michael F. Holick, director of the bone health clinic at Boston University Medical Center.

Osteoporosis is more serious bone loss and is even more likely to lead to fractures. According to the National Osteoporosis Foundation, osteoporosis affects 10 million Americans, most of them older women; an additional 34 million people are at risk of osteoporosis because they already have low bone density, or osteopenia.

The T-score is a comparison of your bone density with the peak bone density of a person of the same sex and race at age 30. A normal T score is arbitrarily set at zero, plus or minus one standard deviation. In other words, any T-score between minus 1 and above is fine. Your score of minus 1.59 is slightly outside this range. To meet the definition of genuine osteoporosis, your T-score would have to be minus 2.5

The Z-score is not very useful. It’s a measure of your bone density compared to other people of the same sex and age. Since you are 60, your Z score of minus 0.4 means that you have slightly lower bone density than other women your age.

In general, whether a person needs to be treated for osteopenia depends on how severe it is and other factors such as whether he or she has had broken bones or taken steroid drugs (which can harm bone tissue). If you need prescription drugs, the choices are usually those used for osteoporosis. These include Fosamax, Actonel, estrogens such as Premarin, estrogen-progestin combinations such as FemHrt or Prempro or a “designer” estrogen called Evista. (Another medication called Forteo, parathyroid hormone (1-34), is only used for outright osteoporosis and even then, only in people who have not responded to other drugs.)

Even if your doctors says you don’t need prescription drugs, you should take at least 1200 milligrams of calcium a day (like TUMS, Caltrate, CitriCal or OsCal) and at least 400 to 800 International Units of vitamin D, says Holick of BU. Weight-bearing exercise is critical, too- you should walk at least three to five miles a week. You should also get a repeat bone density test in a couple of years.

For more information, go to the National Osteoporosis Foundation (www.nof.org)