Thyroid Disease and Aging

What is Thyroid Disease?

Thyroid disorders occur more commonly with increasing age. If you have a thyroid problem, it doesn’t necessarily mean that you will miss out on a happy and healthy life. This pamphlet provides information about the role of your thyroid. It also provides information about the symptoms, causes, and treatment of thyroid diseases that are common in older patients. As with any healthcare issue, always talk to your health provider about your particular situation. What is the thyroid, and why is it important?

The thyroid is an endocrine gland that plays a key role in regulating growth, development, and normal function of the body.1 It is a butterfly-shaped gland located in the front of your neck. The thyroid can affect your heart rate, your emotional state, your feelings of tiredness and hunger, and the condition of your skin and hair. In fact, your thyroid influences most cells in your body.

Your thyroid controls your body’s functions by making several hormones, including thyroxine (T4), which is converted to triiodothyronine (T3).1 If you do not get enough iodine in your diet, your thyroid cannot produce enough T3 and T4. The amounts of T3 and T4 released into the bloodstream:

  • Regulate the body’s ability to turn food into energy
  • Affect rates of tissue growth
  • Affect the function of organ systems throughout the body

What Thyroid Diseases Occur in Older Patients?

With thyroid disease, thyroid hormones are either over-produced or under-produced. Symptoms may differ in older patients compared to younger adult patients.2 Treatment may need to be adjusted for the effects of age, the presence of other health conditions, and medications being taken. Diseases of the thyroid gland include:

  • Hypothyroidism – Not enough thyroid hormone is produced
  • Hashimoto’s disease – An autoimmune disease that causes the thyroid to produce too little thyroid hormone, causing hypothyroidism
  • Hyperthyroidism – Too much thyroid hormone is produced
  • Graves’ disease – An autoimmune disease that causes the thyroid to produce too much thyroid hormone, causing hyperthyroidism
  • Goiter – Enlargement of the thyroid gland
  • Thyroid nodules – Growth of thyroid tissue causing circular or oval-shaped lumps in the thyroid gland
  • Thyroid cancer – Growth of the thyroid gland, either goiter or thyroid nodules, that becomes cancerous

Hypothyroidism and Aging

People with hypothyroidism may experience some of these symptoms or may not notice symptoms at all. You may have few or no symptoms or you may mistake symptoms for the expected effects of aging.2 With an examination, your doctor may detect additional signs of the disease such as slowed heart rate and goiter. Signs and symptoms of hypothyroidism include:

  • Depression
  • Decreased concentration
  • Puffy face
  • Coarseness or loss of hair
  • Hoarseness
  • Muscular pain
  • Brittle nails
  • Cold intolerance
  • Cholesterol abnormalities
  • Fatigue
  • Mental impairment

Thyroid Function and Hypothyroidism

How do I know if I have hypothyroidism?

If you have a family history of thyroid disease or if you report certain symptoms to your doctor, he or she can use several simple laboratory tests to check whether your thyroid gland is functioning normally. Your doctor may order a TSH test, which is the recommended test for evaluating thyroid hormone levels. It measures the level of thyroid-stimulating hormone (TSH), a hormone that controls the amount of thyroid hormone (T4) produced.1 Another test that may be used measures the amount of thyroxine (T4), circulating in your blood. Of these, the TSH test is recognized to be the most sensitive test for detecting too much or too little thyroid hormone.

  • Mild hypothyroidism – TSH levels are elevated, but the thyroid is working harder to produce a normal amount of T4. Signs and symptoms may or may not occur.
  • Overt hypothyroidism – If your thyroid is unable to make enough thyroid hormone, T4 levels fall below the normal range as TSH levels continue to elevate. Signs and symptoms are likely to occur.y

If further testing is needed, your doctor may want to see results of a thyroid scan, an image of your thyroid used to determine whether your whole thyroid or if specific parts are enlarged and not functioning properly. Another option is for your doctor to prescribe a radioactive iodine uptake test. This test will measure how much iodine is absorbed by your thyroid gland and where it accumulates. A thyroid antibody test will determine if your immune system is attacking your thyroid gland, which occurs in Hashimoto’s disease, the most common cause of hypothyroidism.

How is hypothyroidism treated?

Your physician may prescribe medication that replaces the thyroid hormone that the body normally produces. Through a series of blood tests every 6 to 8 weeks, your doctor will decide which precise dose is appropriate for you. Once your doctor has prescribed your appropriate dose, it’s important to remain consistent to avoid over- or under-replacement. Over-replacement may lead to an increased risk of osteoporosis or heart problems. Under-replacement may lead to symptoms such as fatigue, mental dullness, or depression. Your doctor will monitor your disease with periodic TSH tests and may adjust your medication as needed throughout the course of your life.

Hyperthyroidism and Aging

Generally, the symptoms of hyperthyroidism are associated with the body “speeding up.” People with hyperthyroidism may experience some of these symptoms or they may not notice any symptoms at all. Older people, especially, seem to have fewer hyperthyroid symptoms.2 With an examination, your doctor may detect additional signs of the disease, such as rapid heartbeat, goiter, eye problems, or thyroid tenderness. Signs and symptoms of hyperthyroidism include:

  • Nervousness
  • Mental disturbances
  • Sleep disturbances
  • Vision disturbances
  • Thyroid enlargement
  • Rapid heartbeat
  • Weight loss
  • Shortness of breath
  • Heat intolerance
  • Tremor
  • Sudden paralysis
  • Alterations in appetite
  • Frequent bowel movements
  • Menstrual disturbance
  • Impaired fertility
  • Leg swelling
  • Fatigue and muscle weakness

How Do I Know if I Have Hyperthyroidism?

If you have a family history of thyroid disease or you report certain symptoms to your doctor, he or she can use several simple laboratory tests to check whether your thyroid gland is functioning normally. Your doctor may order the TSH test, which measures the level of thyroid-stimulating hormone (TSH), a hormone that controls the amount of thyroid hormone (T4) produced. Another test that may be used measures the amount of the main thyroid hormone (T4) circulating in your blood. Of these, the TSH test is recognized to be the most sensitive test for detecting too much or too little thyroid hormone.

  • Mild hyperthyroidism – TSH levels fall below the normal range and T4 levels are normal. Signs and symptoms may or may not occur.
  • Overt hyperthyroidism – Your thyroid makes too much thyroid hormone. T4 levels rise above the normal range while TSH levels fall below.5 Signs and symptoms are likely to occur.

Thyroid Function and Hyperthyroidism

If further testing is needed, your doctor may want to see results of a thyroid scan, an image of your thyroid used to determine if your whole thyroid or if specific parts of your thyroid, or nodules, are hyperactive. Another option, your doctor may prescribe a radioactive iodine uptake test. This test will measure how much iodine is absorbed by your thyroid and where it accumulates.

How is hyperthyroidism treated?

The treatment for hyperthyroidism varies between patients. If you have hyperthyroidism, your age, severity of disease, overall state of health, and other factors all play a role in what your doctor chooses for you. One or more of the following treatments may be used:

Antithyroid drugs. These drugs block the ability of the thyroid to produce thyroid hormone. They do not damage the thyroid gland and may be used for short- or long-term treatment. Antithyroid drugs are also used to prepare a patient for treatment with radioactive iodine or for surgery.

Radioactive iodine. This treatment, usually a pill taken once by mouth, damages or destroys thyroid cells that produce excess thyroid hormone. This process may take a few weeks or months. The thyroid gland is reduced in size, and the amount of hormone produced is also reduced. People given this treatment commonly become hypothyroid, which can be treated with medication.

Surgery. Surgery may remove all or part of the thyroid to cure hyperthyroidism. This treatment often results in hypothyroidism. To maintain adequate levels of thyroid hormone in the body, daily treatment with thyroid hormone replacement will be required after surgery.

Beta-blockers. These drugs help reduce some of the symptoms of hyperthyroidism, such as rapid heart rate and nervousness.

Therapy for hyperthyroidism in older people must be closely monitored for its potential effects on other body systems, including the heart.2 It is important to follow your doctor’s directions and to have your thyroid hormone levels checked regularly to see if your medication needs adjustment.

How Can I Manage the Health of My Thyroid?

  1. Pay attention to how you feel, and report symptoms to your doctor. If you are a woman, older than age 60, have an autoimmune disease (such as type 1 diabetes or rheumatoid arthritis), have a family history of thyroid disease or have had surgery or radiation therapy, you may need to be tested more frequently.
  2. If you suspect that you may have thyroid disease, ask your doctor about a TSH test.If you have concerns and symptoms of thyroid disease, you should discuss them with your doctor.
  3. If you have thyroid disease, follow your doctor’s directions. Take your medications exactly as prescribed by your doctor.
  4. Have your thyroid function checked every year. An annual TSH test can confirm if your thyroid is functioning normally.

Tips on Taking Medication

If you have hyperthyroidism that is treated with surgery or radioactive iodine, you may develop hypothyroidism after treatment. If you become hypothyroid and thyroid hormone replacement is prescribed, consider the following advice:

  1. Take your medication every day, as prescribed.
  2. Take your medications at the same time every day. If you’re taking other medications, prescribed or over-the-counter products, including vitamin supplements, consult with your doctor.
  3. Tell your doctor if you stop taking one of your regular medications or start taking a new one.