What is Graves Disease?
Graves’ disease is an autoimmune disorder, which affects the thyroid gland causing it to become overactive. In Graves disease, the body creates antibodies against the receptor on the thyroid gland, the antibodies then act like a normal hormone in the body (the thyroid stimulating hormone) and excite the thyroid gland. As a result of this heightened stimulation, the thyroid produces an excess amount of the thyroid hormones, T3 and T4.
Signs and Symptoms
People with Graves’ disease develop a number of signs and symptoms. Patients often experience unexplained weight loss; which can sometimes be so severe it is misdiagnosed as anorexia nervosa. The thyroid hormones are involved in regulating metabolism; and when there are excessive levels, metabolism increases leading to weight loss. Another common symptom is feeling hot, especially when others are not, this is because thyroid hormones are important in maintaining our body temperature, and when they are overactive they cause an increase in heat production in the body. Patients also complain of excessive perspiration or feeling thirsty. Often in Graves’ disease, the thyroid enlarges and forms a visible swelling at the front of the neck called goitre. The enlargement arises as a result of constant stimulation by the antibodies.
Other signs and symptoms experienced by people with Graves’ disease include:
- Tachycardia (fast heart rate)
- Hypertension (high blood pressure)
- Heart palpitations
- Nausea and gastrointestinal discomfort
- Fatigue
- Diarrhoea
- Frequent urination
- Difficulties during pregnancy, such as weight loss
- Thyroid eye signs
- Skin changes – Graves’ dermopathy
Some patients with Graves’ disease also develop Graves’ ophthalmopathy, a condition which affects the eyes. However, not all patients with Graves’ disease have Graves’ ophthalmopathy, and not all cases of Graves’ ophthalmopathy are caused by Graves’ disease. However, this process is not well understood; but is believed to be due to separate hormones that may affect the eyes, or that cell types in the eyes may also express the TSH receptors, which are affected by the antibodies. The eyes become very red and very swollen, and appear to bulge out of their sockets. Patients may experience visual disturbances, such as blurred or double vision. The eyes become dry, and patients can experience difficulty closing their eyes.
Risk Factors
A number of predisposing risk factors for Graves’ disease have been identified such as, Graves’ disease has been found to be around 8 times more common in females than males. It is also more common during pregnancy and in the year following pregnancy. Most cases of Graves’ disease start between the ages of 20 and 40 years old. It is more common in people with previous thyroid dysfunction. Smokers have an increased risk of developing Graves’ ophthalmopathy, and exhibit a poorer response to treatment. Medications, stress and trauma to the thyroid may also be predisposing factors.
Treatment
Treatment for Graves’ disease can be medical, surgical or radiological.
Anti-thyroid medications reduce the amount of thyroid hormones being produced. These may be used as treatment on their own but also commonly precede thyroidectomy (surgical removal of the thyroid) to stabilise the thyroid to a normal state prior to operating. There are risks with operating on hyperthyroid patients, and reducing the activity of the thyroid prior to the procedure will decrease these risks.
If other therapies aren’t an option or aren’t effective, you may need surgery to remove your thyroid gland. Complications are rare under the care of a surgeon experienced in thyroid surgery.
Radioactive iodine treatment can also be used in Graves’ disease as it is selectively taken up in the thyroid gland, making this a highly specific form of treatment. The patient is exposed to radioactive iodine; once this is taken up, it will destroy the cells of the thyroid and improve the signs and symptoms of the disease.
Radioiodine therapy may increase your risk of new or worsened symptoms of Graves’ ophthalmopathy. This side effect is usually mild and temporary, but the therapy may not be recommended if you already have moderate to severe eye problems.
Other side effects may include tenderness in the neck and a temporary increase in thyroid hormones. Men may experience a temporary reduction in testosterone levels. Radioiodine therapy isn’t used for treating pregnant or nursing women.
Following treatment for Graves’ disease with either radioiodine or surgery, you are likely to become hypothyroid, and will require lifelong thyroid replacement therapy. Thyroid hormone replacement will supply your body with normal amounts of thyroid hormones in the long term.
If you have questions or concerns about graves disease or thyroid problems see your local doctor who will arrange for you to see a thyroid surgeon.