Graves' Disease
Overview
Graves’ disease is an autoimmune disorder that impacts the function of the thyroid gland, leading to excess hormone production that results in symptoms such as increased heart rate and metabolism, as well as other serious complications, if left untreated.
About 1% of people in the United States have Graves’ disease. It is the most common cause of overactive thyroid (hyperthyroidism) among Americans. Women are five times more likely to develop Graves’ disease than men. The condition is more common among people aged 30 and older, although it may be diagnosed at any age, even in children.
Graves’ disease is not fatal, but complications may negatively impact a person’s overall health or life expectancy. When Graves’ disease is untreated or is not well-controlled, some people may experience complications like arrhythmia, heart failure, or stroke. The condition may also increase the risk of osteoporosis and broken bones.
Although there is no cure for Graves’ disease, treatments are available to help manage the condition.
What is Graves’ disease?
Graves’ disease, an autoimmune condition, impacts the production of hormones by the thyroid gland. It is the most common cause of hyperthyroidism, which is the overproduction of thyroid hormones.
The thyroid gland is located in the lower part of the neck. It naturally produces enough thyroid hormone, using iodine from food sources, to help control metabolism, weight, body temperature, heart rate, menstrual cycles, and other bodily functions. Thyroid hormone production is managed by the pituitary gland, which makes thyroid-stimulating hormone (TSH)—the hormone that essentially tells the thyroid to produce higher or lower hormone levels, based on the body’s needs at a given time.
When a person has Graves’ disease, the immune system produces antibodies that mistakenly cause the thyroid to overproduce thyroid hormone. These antibodies are known by two names: Thyroid-stimulating immunoglobulins (TSI) and/or thyroid-stimulating antibodies (TSAb). These antibodies spur the thyroid to keep producing thyroid hormone, despite the controls put in place by the pituitary gland. As a result, people with Graves’ disease produce more thyroid hormone than the body needs.
Elevated thyroid hormone levels increase the heart rate and metabolism, which may cause heart palpitations and unintentional weight loss, in addition to other symptoms.
Up to half of people with Graves’ disease also experience Graves’ ophthalmopathy, an inflammatory eye condition that may lead to vision loss if left unaddressed.
What causes Graves’ disease?
The cause of Graves’ disease is not yet known, but researchers believe some people have a genetic predisposition to the condition, and may develop this autoimmune disease after being exposed to one or more of the following external triggers:
- Viral infections
- Bacterial infections
- Changes in hormone levels (in women)
- Having iodine levels that are higher than normal
What are the symptoms of Graves’ disease?
People who have Graves’ disease may experience one or more of the following symptoms:
- Anxiety or nervousness
- Fatigue
- Difficulty concentrating
- Memory problems
- Rapid heartbeat or irregular heartbeat
- Heart palpitations and/or chest pain
- Increased appetite
- Diarrhea
- Hand tremors
- Sweating
- Difficulty sleeping
- Moodiness or irritability
- Weight loss
- Hair loss
- Infrequent menstrual periods
- Lighter-than-normal menstrual flow
- Enlarged breasts (among men)
- Enlarged thyroid (goiter)
- Muscle weakness
- Difficulty swallowing
- Difficulty breathing
- Eye pain
What are the risk factors for Graves’ disease?
People who are at increased risk of Graves’ disease are:
- Female
- Age 30 or older
- Smokers
- Women in the postpartum period
- People who experience a lot of stress
- People who receive highly active antiretroviral therapy (HAART)
- People who are exposed to high levels of iodine
- Children with Down syndrome
- Children with DiGeorge syndrome
Certain autoimmune conditions make people more likely to have Graves’ disease, including:
- Rheumatoid arthritis
- Type 1 diabetes
- Autoimmune gastritis
- Vitiligo
- A family history of Graves’ disease
- A family history of Hashimoto’s disease
- A close family member who has Graves’ disease or another autoimmune disorder
How is Graves’ disease diagnosed?
To diagnose Graves' disease, your doctor may review your medical history, perform a physical exam, and order one or more diagnostic tests.
It’s important to tell your doctor if you or anyone in your family has any autoimmune diseases, including Graves’ disease. Your doctor may ask if you smoke, experience high levels of stress, or have recently been pregnant. You should also communicate any symptoms, including weight loss despite an increased appetite, to your doctor.
During a physical exam, your doctor will check for signs of hyperthyroidism, such as an increased heart rate, unexplained weight loss, hair loss, and eyes that appear to bulge. Additionally, your neck may be examined to check for signs of an enlarged thyroid gland.
When Graves’ disease is suspected, the following tests may be used to confirm the diagnosis:
- Blood tests, which can determine whether normal levels of the thyroid hormones thyroxine (T4) and triiodothyronine (T3), as well as thyroid stimulating hormone (TSH), are being produced. In Graves’ disease, T4 and T3 are elevated, while TSH is low (suppressed). They may also indicate the presence of the antibody thyroid-stimulating immunoglobulin (TSI), which is elevated in people with Graves’ disease.
- A thyroid scan with radioactive iodine, to determine whether the thyroid takes up higher-than-normal levels of iodine from the bloodstream. After patients swallow a radioactive iodine pill, doctors use a gamma probe 4 to 6 hours later, then again 24 hours later, to see if the thyroid is collecting more iodine from the bloodstream than it should.
- A Doppler ultrasound, which allows doctors to see the size and shape of the thyroid gland and to look for any thyroid nodules.
How is Graves’ disease treated?
There is no cure for Graves’ disease, but the following treatments may help manage the condition:
- Beta-blockers, which may reverse hyperthyroidism symptoms. This medication may slow a rapid heartbeat, reduce perspiration, and help to lower anxiety levels.
- Anti-thyroid medications, including methimazole and propylthiouracil. These drugs alter the way the thyroid interacts with iodine, preventing the gland from producing thyroid hormone.
- Radioactive iodine treatments, which destroy a portion, or all, of the thyroid, preventing it from producing too much hormone. If the gland is completely destroyed, patients need to take levothyroxine, a thyroid hormone replacement medication, for the rest of their lives.
- Surgery, during which all of the thyroid is removed (total thyroidectomy). Once the thyroid gland has been removed, thyroid hormone cannot be produced, thereby eliminating hyperthyroidism. If the entire gland is removed, patients will need to take levothyroxine, the thyroid hormone replacement medication, for the rest of their lives.
Different treatments are available for people with Graves’ ophthalmopathy, including artificial tears and oral or intravenous corticosteroids, to manage eye-related symptoms. These treatments may help to preserve the patient’s vision. Tepezza® (teprotumumab) is a monoclonal antibody treatment that treats Graves’ ophthalmopathy.
What is the outlook for people with Graves’ disease?
People with Graves’ disease may be able to manage their condition with medication and other treatments. A small percentage of people with Graves’ disease, especially those with mild Graves’ disease, may go into remission. The remission may only be temporary, particularly among children.
Complications of Graves’ disease, including arrhythmia, heart failure, or stroke, may shorten an individual’s life expectancy, but these complications are not common among people who manage their disease.
What makes Yale unique in its treatment of Graves’ Disease?
“At Yale, we have a multidisciplinary, patient-centered approach for patients with Graves’ disease, including specialized thyroid endocrinologists, nuclear medicine specialists, ophthalmologists, and endocrine surgeons,” says chief of Yale Medicine Endocrine Surgery Jennifer Ogilvie, MD. “We work as a team to design the best treatment options for each patient.”