Get a Thyroid Test

If

you're like most people, you've never given your thyroid a second thought. Shaped like a bow tie and wrapped around the windpipe at the base of the throat, the thyroid helps regulate your body's metabolism much as a thermostat controls the temperature in your house. But if you're female and 50 or older--or love someone who is--you need to consider whether the old thermostat is still working. Last week the American College of Physicians, a conservative arbiter of treatment standards, recommended a blood test for thyroid disorders at least once every five years for all women in this age group.

The advice comes as something of a reversal for the A.C.P. Back in 1990, it argued that routine screening was unnecessary because doctors could pick up most thyroid disorders on their own. Since then, however, studies have shown that among women who are middle-aged and older, 1 in 71 suffers from a thyroid disorder that is severe enough to cause problems but has never been diagnosed. (Men also develop thyroid disease as they age, but at a much lower rate.) Why do doctors miss so many cases? Turns out that many symptoms associated with thyroid disorders mimic the signs of aging.

Which disorders and what symptoms? Generally the thyroid causes problems in two different ways. The more common disorder, hypothyroidism, occurs when the gland fails to produce enough thyroid hormone. The body's metabolism slows down, and the patient complains of not having any energy and feeling mentally sluggish.

By contrast, if the thyroid works too hard, a condition called hyperthyroidism, it can rev your body up to the point that your hands tremble. You have trouble falling asleep, and your heart quivers in a dangerous pattern called atrial fibrillation. In an extreme case, your eyes will bulge.

Fortunately, there is a fairly simple blood test, called a TSH test, that helps doctors determine whether you have a thyroid disorder. The cost ranges from $30 to $50, but the test can be conducted as part of a regular battery of blood work for cholesterol and other substances.

If you have hypothyroidism, a drug called thyroxine can boost your hormone levels. Dr. Mark Helfand, an internist at the Veterans Medical Center in Portland, Ore., and a co-author of the new guidelines, says those who take the drug will "need it the rest of their life, and should be monitored every six months or so to make sure they don't get too much."

If you have hyperthyroidism, drugs can slow down the thyroid or, if need be, radioactive iodine can destroy it completely--at which point you will have to take thyroxine.

As helpful as the new guidelines will be for detecting clear-cut cases of thyroid disease, there is one controversy women should be aware of. Screening will pick up lots of borderline cases. As many as 10% of older women may have slightly abnormal blood tests but appear to be otherwise healthy. Sometimes their hormone levels will return to normal after a few months. So far, there hasn't been a research study large enough to determine whether they should be taking drugs as well. Until there is, most doctors will be understandably reluctant to treat a woman whose only symptom is an oddball number on a blood test.

Learn more about thyroid disorders at time.com/personal and read about the new guidelines at www.acponline.org