Graves Disease: Description:
The thyroid is a small, butterfly-shaped gland in the front of the neck below the larynx, or voice box. The thyroid gland makes two thyroid hormones, triiodothyronine (T3) and thyroxine (T4). Thyroid hormones affect metabolism, brain development, breathing, heart and nervous system functions, body temperature, muscle strength, skin dryness, menstrual cycles, weight, and cholesterol levels. Thyroid hormone production is regulated by another hormone called thyroid-stimulating hormone (TSH), which is made by the pituitary gland located in the brain.
Graves disease is a type of autoimmune disease that causes over-activity of the thyroid gland, causing hyperthyroidism. This over-activity is also sometimes called "toxic diffuse goiter." The thyroid gland helps set the rate of metabolism, which is the rate at which the body uses energy. When the thyroid is too active, it makes more thyroid hormones than the body needs. High levels of thyroid hormones can cause side effects such as weight loss, rapid heart rate and nervousness. This is an uncommon disease that affects 2 percent of all women at some time in their lives. Graves' disease also tends to affect women between the ages of 20 and 40, although it occurs in infants, children, and the elderly. Graves' disease is the most common cause of hyperthyroidism in the United States.
The most common symptoms of Graves' disease include:
- Frequent bowel movements.
- Weight loss without dieting.
- Changes in vision.
- Heat sensitivity.
- Increased sweating.
- Muscular weakness.
- Lighter menstrual flow.
- Rapid heart beat.
- Hand tremors.
In addition, the eyes of people with Graves' disease may appear enlarged because their eyelids are retracted and their eyes bulge out from the eye sockets. This condition is called Graves' ophthalmopathy.
A small number of people with Graves' disease also experience thickening and reddening of the skin on their shins. This usually painless problem is called pretibial myxedema or Graves' dermopathy.
Causes and Risk Factors:
Scientists do not know exactly why some people develop Graves disease, but they believe factors such as age, sex, heredity, and emotional and environmental stress are involved.
Graves disease usually occurs in people younger than age 40 and is five to 10 times more common in women than men. An individual's chance of developing Graves' disease increases if other family members have it.
The following risk factors are linked to a higher probability of developing Graves disease:
Genetics - People with a family history of Graves' disease are more likely to develop it themselves. Researchers have not been able to find a specific gene that causes the disease to be passed from one generation to the next. Scientists know that some people inherit an immune system that can make antibodies against healthy cells, but predicting who will be affected is difficult.
- Gender - For every male with Graves' disease there are seven females with the disease.
- Age - The vast majority of patients experience the onset of the disease after they are 20 years old.
- Mental stress.
Physical examination - the GP (general practitioner, primary care physician) or specialist examines the patient's eyes to see whether they are bulging or irritated. The thyroid is examined to determine whether it is enlarged. The doctor will also check the patient's heart rate and blood pressure. The physician will check for signs of trembling of the hands or fingers (tremor). During the interview the patient will be asked about their symptoms, medical and family medical histories.
The ultrasensitive TSH test is usually the first test a doctor performs. This test detects even tiny amounts of TSH in the blood and is the most accurate measure of thyroid activity available. Another blood test used to diagnose Graves' disease measures T3 and T4. In making a diagnosis, doctors look for below-normal levels of TSH, normal to elevated levels of T4, and elevated levels of T3.
Because the combination of low TSH and high T3 and T4 can occur with other thyroid problems, doctors may order other tests to finalize the diagnosis. Two of these tests are based on the fact that the thyroid gland uses iodine to make thyroid hormone. Both tests use small, safe doses of radioactive iodine.
Doctors may also consider the thyroid-stimulating immunoglobulin test, although this test usually is not necessary to diagnose Graves' disease. This test, also called a TSH antibody test, measures the level of TSI in the blood. Most people with Graves' disease have this antibody, but people whose hyperthyroidism is caused by other conditions do not.
The purpose of treatment is to control the overactivity of the thyroid gland. Beta-blockers such as Propranolol are often used to treat symptoms of rapid heart rate, sweating, and anxiety until the hyperthyroidism is controlled.
Medicine: There are some medicines called antithyroid drugs that can lower the amount of thyroid hormones made by the thyroid, causing it to make, normal levels. A doctor must give these medicines to you. Some patients who take an acute thyroid drug for 1 to 2 years have a remission from Graves' disease; their thyroid function may remain normal even without medication.
Radioactive iodine: The radioactive iodine damages thyroid cells, shrinking and eventually destroying the thyroid gland in order to reduce hormone levels. Like surgery, this condition usually leads to hypothyroidism, so that thyroid hormone supplement medication is needed for the rest of the patient's life.
Surgery: All of the thyroid gland will be removed. In most cases, people who have surgery for Graves disease will develop an under-active thyroid (hypothyroidism, the opposite of hyperthyroidism), and will have to take thyroid replacement hormones for the rest of their lives.
If you have Graves disease, make your mental and physical well-being a priority. Eating well and exercising can enhance the improvement in some symptoms while being treated and help you feel better in general.
DISCLAIMER: This information should not substitute for seeking responsible, professional medical care.