Gaining weight, losing weight, exhaustion, the blahs, anxiousness, insomnia, constipation, hair loss, dry skin, pounding heart, infertility -- just about any ailment that can plague a woman often can be traced back to a small, butterfly-shaped gland in the neck called the thyroid. More than 13 million Americans have thyroid problems, and half do not know it.
There is a laundry list of symptoms associated with both hypothyroidism (underactive) and hyperthyroidism (overactive). However, Elizabeth Lee Vliet, MD, an internist in Dallas and author of Screaming to be Heard: Hormone Connections Women Suspect, and Doctors Still Ignore and Women, Weight and Hormones, says none of this is as clear cut as many doctors think. For one thing, she says, the thyroid regulates every cell in the body, including the ovarian hormones, and the secondary effects of an imbalance in these hormones can exacerbate problems with the hormones secreted by the thyroid.
What Goes Wrong
Perhaps for this reason, women are five to seven times more likely than men to experience thyroid problems. As many as 10% develop a thyroid problem after giving birth. The most common single disorder is an autoimmune problem (in which the body "fights" itself) called Hashimoto's disease, which results in underactive thyroid. Women with other autoimmune disorders are at prime risk for some form of thyroid dysfunction. "There is also evidence," Vliet says, "that pollutants such as PCBs and dioxin can damage the thyroid gland [in the womb]." Other culprits are radiation to the neck area and certain medications.
Most women suffering from hypothyroidism, says Mary Shomon, author of Living Well With Hypothyroidism: What the Doctor Doesn't Tell You ... That You Need to Know, go to the doctor because they are fatigued. "You sleep 10 hours and then need a nap," she says. Other symptoms are weight gain or inability to lose weight, feeling cold, constipation, dry skin, dry hair, hair loss (eyebrows, too), high cholesterol that doesn't submit to drugs or diet, drastically reduced sex drive, and brain fog. Hypothyroidism can also prevent you from getting or staying pregnant and cause a full-feeling neck, swollen hands and feet, muscle pain, carpal tunnel syndrome, or other tendinitis. In short, you may feel lousy.
In the case of an overabundance of thyroxin flooding through the system and supercharging every cell to an unhealthy degree, the result can be another autoimmune disorder called Grave's disease. Although late in the progression you may lose weight, Vliet says, at first you will be gaining just as with hypothyroidism. Other symptoms apart from the dry hair and skin and hair loss include a restlessness, inner tension, tossing and turning, and an agitated sort of depression. Despite the misdirected energy, fatigue is a symptom of an overactive thyroid, too. Having hyperthyroidism, Vliet says, is like sitting in park with your foot on the accelerator. Sometimes Grave's disease causes the eyes to bulge slightly. (Graves, Vliet says, is also related to postpartum psychosis in which the ovarian hormones join with the thyroid hormones to produce psychiatric symptoms.)
Art of Testing
Shomon urges women not to drag (or rev) around feeling bad but to consult a doctor. Probably the first test that will be done is a TSH test for thyroid stimulating hormone, a substance produced by the pituitary gland that regulates the thyroid gland. If the TSH is greater than the upper level of normal (4.5 to 5 mU/L), many doctors will check the "free" T4 level (thyroxin), which costs less than a T4 index, which tests both T3 and T4. A TSH above 2 can mean fertility is impaired, Vliet says.
Kenneth R. Blanchard, MD, an endocrinologist in Newton, Mass., says what he learned in medical school -- to test only TSH -- was flat wrong. He always tests for T3 and T4. "I have seen people living in misery with 100% T4," he emphasizes. Vliet also tests for T3 and T4, as well as antibodies that can cause autoimmune problems. "You can have shortages of T3 and T4 before the TSH goes up or down," she says. "Women with significantly elevated antibodies may need medication before the TSH reaches 4 or 5."
"We're patients, not lab values" is Shomon's motto. She says the range of "bad" test results is too small and that doctors will dismiss the same set of symptoms in one woman as hypochondria if the test readings are a few tenths of a point lower than in another woman with the same complaints. Vliet and Blanchard specialize in nailing down and treating thyroid dysfunction at varying levels for each woman.
Treatment of both hypo- and hyperthyroidism is not totally benign. A careful diagnosis is important.
Hypothyroid is an underproduction of thyroxin, so levothyroxine sodium (Synthroid, Levoxyl) is given. "They used to tell you one pill a day and you'll be fine," Shomon says. Now, she and Blanchard recommend giving T3. "In a low dose," Vliet says. "High-dose T3 can cause heart attacks."
As for treating hyperthyroidism, radioactive iodine is sometimes used or the gland is surgically removed. Treating hyperthyroidism is tricky. Vliet herself immediately defers to an endocrinologist.
Shomon urges baseline testing for women at 35, as well as at least a TSH test before getting pregnant, four months postpartum, and before starting on antidepressants or hormone replacement therapy. "If your HMO won't cover the test, you can get an FDA-approved home test." With the fine-tuning required with this delicate gland, however, a doctor's supervision is highly recommended.
Star Lawrence is a medical journalist based in Chandler, Ariz.