Disorders of this small gland are common, especially in older women.
Catherine Horvath, 51, was feeling no symptoms five years ago when her doctor ordered a routine blood test to check, among other things, how her thyroid was doing. (Your thyroid is the butterfly-shaped gland low in your neck that influences metabolism, growth and development and body temperature.)
The results showed astoundingly low levels of thyroid hormone — a sign her thyroid function was, as she puts it, “pretty close to being nonexistent.” If untreated, she was at risk not only for bothersome symptoms but for other serious diseases as well.
The fix was simple: One pill a day to replace the thyroid hormone she wasn’t making. Within a year, Horvath's levels were back to normal. “It doesn’t really affect my life,” says Horvath, who lives in Santa Cruz, Calif. “I manage it by taking a pill every day.”
A Common Disease
Horvath is one of the estimated 24 to 28 million Americans who likely have some form of thyroid disease, many of whom develop the disorder later in life. Yet according to American Association of Clinical Endocrinologists, nearly half of those with thyroid disease don’t know they have it or are misdiagnosed.
That’s because thyroid disease — particularly among older adults, when the disorders can become more common — often masquerades as other ailments.
Hypothyroidism, an underperforming thyroid and the most common of thyroid diseases, may be overlooked by older people who dismiss its symptoms of fatigue, constipation, dizziness or weight gain as simply the price of getting older.
An overactive thyroid, or hyperthyroidism, can look like heart rhythm problems, muscle weakness, anxiety or age-related osteoporosis.
Thyroid lumps are much more common among older people, yet often can’t be detected without a neck exam. While most lumps are benign, some are cancerous and require treatment.
As many as 10 percent of Americans older than 60 have some form of thyroid disorder, says Dr. Hossein Gharib, an endocrinologist with the Mayo Clinic College of Medicine, who has most recently served as president of the American Thyroid Association. The thyroid hormone replacement drug Synthroid (levothyroxine), used for underactive thyroids or when the thyroid has been removed, is the second most dispensed medication in the United States, with more than 22 million prescriptions written annually.
“People do not always recognize thyroid disease because they might think it is just a normal part of aging,” Gharib says. “That’s why it’s important to ask for thyroid screening.”
A simple blood test will reveal whether your thyroid is doing its job.
The thyroid's hormones, known as T3 and T4, are released in response to the ebb and flow of TSH, or thyroid stimulating hormone, which is produced by the pituitary gland. If a thyroid is working normally, the pituitary gland gets the message to keep the TSH within a fairly tight range.
But if a blood test shows TSH levels are too high or too low, that might mean the thyroid is having trouble. For older adults, this often means a sluggish thyroid, or hypothyroidism, with symptoms that include impaired cognitive function, fatigue, intolerance to cold, weight gain or itchy skin.
“Thyroid disease can happen at any stage in life, but the risk for hypothyroidism increases as we age,” says Dr. Mack Harrell, a thyroid specialist in Hollywood, Fla., and president of the American Association of Clinical Endocrinologists.
Time is often the culprit. Doctors say many thyroid disorders start early in life as smoldering autoimmune disorders, when the body’s natural defenses turn against the thyroid and attack it. Over decades, those attacks begin to damage the thyroid’s cells enough to start lowering thyroid hormone levels.
Women At Risk
Women, it seems, are particularly vulnerable.
“Women get more thyroid disease of every variety than men,” Harrell says. “They outdo men 3- or 4-to-1 for everything.”
The reason isn’t clear, he and others say. Hormonal fluctuations during the reproductive years may stress the thyroid as well, taking a toll over decades.
Women are also more prone than men to all autoimmune disorders.
About five years after her hypothyroidism diagnosis, Horvath developed scleroderma, another autoimmune disease causing a buildup of collagen that painfully stiffens and swells her hands, feet and arms. The condition has disabled her significantly, she says.
“Autoimmune diseases do tend to run in clusters,” Harrell says, “and thyroid disease is the most common autoimmune disease.”
The opposite of a sluggish thyroid, or hyperthyroidism, is less common among older adults. But Harrell and others say it’s a particularly dangerous condition because it targets key vulnerabilities in aging bodies.
When your thyroid produces more hormone than the body needs, your metabolism goes into overdrive. Symptoms can include hand tremors and rapid or irregular heartbeat, leading to serious cardiac problems. Too much thyroid hormone can also leech away calcium in bones, leading to osteoporosis.
At younger ages, a revved-up thyroid often develops when the immune system stimulates parts of the thyroid to overproduce. In older ages, hyperthyroidism often stems from lumps or nodules that form on the gland, some of which can grow so large they simply pump out too much hormone.
And — you guessed it — older people, particularly women, are far more likely to have lumpy thyroids than those at younger ages.
“If you’re over the age of 50, and you’re female in this country, you have a 1 in 2 chance of having a lumpy thyroid,” Harrell says.
To treat an enlarging nodular thyroid, as it is called, doctors can surgically remove the thyroid, which presents some risk but is sometimes a better option for healthy patients with many years ahead. Other treatments include anti-thyroid medications or radioactive iodine, although those can damage the liver or may not always be successful.
Cancer a Possibility
Lumpy thyroids carry an increased risk of another thyroid disorder: cancer. While the vast majority of lumps are benign, about 6 percent are not, which is significant considering half of all women over 50 and an estimated 90 percent of women over age 70 have lumps.
Within the past 15 years, the number of patients diagnosed yearly with thyroid cancer has increased dramatically, from 18,000 to 65,000. The reason isn’t entirely clear, although many experts believe it’s largely due to better diagnostic methods.
The good news is that, once detected, the vast majority of thyroid cancers are very treatable with surgery, with a high survival rate over years.
A simple neck examination led to Jeani Adams’ diagnosis of thyroid cancer at age 40. Now, 17 years later, the Richland, Wash., woman says she shows no signs except a scar from surgery. But considering the alternative, she says, that’s just fine.
Wondering how to boost your thyroid health? Here are some tips about the best ways to stay aware:
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