A Look at Thyroid Disease

by Tina Coleman

Because the signs and symptoms of early thyroid disease can be vague and diffuse, we often attribute them to stress or advancing age. In fact, according to figures from the Thyroid Foundation of America, Inc., approximately 14 million people in the United States suffer some type of thyroid dysfunction. However, more than nine million of these people don't even realize they're sick. Are you one of them?

Approximately one in eight women will develop a thyroid problem during her lifetime. In fact, thyroid disease is four to five times more common in women than it is in men. By asking your doctor to perform a simple test, you could be on your way to improving your quality of life.

What Is the Thyroid?

The thyroid gland is a butterfly-shaped gland covering the windpipe just below the Adam's apple in your neck. It is part of the endocrine system, one of the most important systems in the human body. Endocrine glands regulate tissue and organ function, metabolism, and growth and development by secreting hormones into the bloodstream. Thyroid hormones regulate cell metabolism (energy production), which affects nearly every organ and cell in the body.

When the thyroid gland releases fewer hormones than the body needs, the result is hypothyroidism, the most common form of thyroid dysfunction. When more hormones are released than necessary, the result is hyperthyroidism. Timely detection and proper treatment of these conditions allows patients to lead normal active lives. But, left untreated, serious negative health consequences can result, including consequences to the cardiovascular system, reproductive system, nervous system, and other major organ systems.

Symptoms of Thyroid Disease

According to the American Association of Clinical Endocrinologists (AACE), symptoms of hypothyroidism include the following:

The AACE's list of hyperthyroidism symptoms include the following:

• Nervousness
• Irritability
• Difficulty sleeping
• Bulging eyes, unblinking stare
• Changes in vision
• Goiter (enlarged thyroid gland)
• Rapid heartbeat
• Increased sweating
• Heat intolerance
• Unexplained weight loss
• Scant menstrual periods
• Frequent bowel movements
• Warm, moist palms
• Fine tremor of the fingers

A Disease That Sneaks Up on You

Thyroid disease, says H. Jack Baskin, MD, president of the AACE, usually begins in puberty and increases during the teen years, reaching its peak in the 20s and 30s.

"By age 40, it's said that close to 10% of women have a thyroid problem. By age 60, it's more like 15% to 20%," he says. "It can be months or years before a thyroid problem is pinned down as the cause of symptoms."

Dr. Baskin adds that weight loss associated with hyperthyroidism is not as common a symptom as thought; and it is never the only symptom. It is also believed that increased levels of thyroid hormone in the body during the year following pregnancy may be a cause of postpartum depression in some women.

Much thyroid disease is currently thought to be an “autoimmune disorder�?in which the body’s own cells attack (in hypothyroidism) or stimulate (in hyperthyroidism) the thyroid gland. The tendency toward developing either thyroid disorder (hypo or hyper) is commonly hereditary, particularly in females.

"If a mother has it, her daughter has a 25%-50% chance of developing it, although it may not necessarily be the identical disorder," Baskin says. In other words, the daughter of a mother with hypothyroidism may develop hyperthyroidism, or vice versa.

It is also believed that 5%-9% of women develop thyroid disorders following childbirth. They experience transient hyperthyroidism followed by hypothyroidism which may be responsible for a substantial proportion of depression following childbirth.

Testing, Testing...

Not everyone with a thyroid problem experiences the same symptoms. If you are experiencing any combination of the above symptoms, you should specifically ask your doctor to perform a thyroid stimulating hormone (TSH) test. Although this is a particularly sensitive test, it is not as easy as the T4 test, which measures the level of thyroid hormones in the bloodstream.

Dr. Baskin says the T4 test is not as sensitive an indicator of thyroid disease, and people can become quite ill before the T4 test results finally come back abnormal. Results of the T4 test may also be skewed if a person is taking birth control pills or certain medications.

The TSH test is more clinically useful than the T4 test, as it measures the thyroid-stimulating hormone released by the pituitary gland to signal the thyroid to produce hormones. If TSH is high, the thyroid isn't producing enough hormones; the pituitary secretes a lot of TSH to encourage the thyroid to release more thyroid hormone. If TSH is low, the thyroid is producing too many hormones; the pituitary is telling the thyroid to slow down.

Another advantage of the TSH test is that it can detect thyroid problems much earlier than the T4 test, allowing doctors to institute treatment before symptoms and potential organ damage can occur.

The AACE recommendation states that any woman over the age of 40 be screened periodically with a TSH test. Baskin himself further recommends that the test be performed "at least every two years," and that women with a family history of thyroid disorders be screened every two years after the age of 20 (with a TSH test) and annually after the age of 40.

Treatments for Thyroid Disease

Thyroid disorders are treatable.

Hypothyroidism

If you are diagnosed with an underactive thyroid (hypothyroidism), normal thyroid levels may be attained by supplementing the body's hormone with a synthetic hormone medication called levothyroxine sodium. This medication is available in tablets and must be taken daily for life. The dosage prescribed by a physician is carefully and gradually adjusted until a normal TSH level has been achieved. The TSH test will have to be repeated periodically (usually during an annual physical, but more frequently at first) to ensure that the dosage continues to be appropriate.

Medication adherence is crucial, as under-replacement of the hormone will not control the symptoms of hypothyroidism and will not prevent potential organ damage. Over-replacement, on the other hand, can cause hyperthyroidism and may put some patients at risk for osteoporosis and other problems.

Hyperthyroidism

If you are diagnosed with hyperthyroidism, the treatment is more complex and can include antithyroid drug therapy (ADT), radioactive iodine treatment, or thyroid surgery. Radioactive iodine therapy is currently the most commonly recommended treatment. A few kinds of hyperthyroid problems may not require treatment, either because they improve on their own or because they aren’t sufficiently severe. Only your doctor can advise you about whether your problem does or does not need treatment.

Remember, if you are experiencing symptoms or have a family history of thyroid disease, don't be afraid to ask your doctor to perform a TSH test. Timely detection and treatment of a thyroid disorder can greatly enhance your quality of life—for the rest of your life.