Graves' Disease: Causes and Symptoms

Graves' disease is an autoimmune disease that affects the thyroid gland. It causes the gland to enlarge (twice its size) and become hyperactive, thereby resulting into hyperthyroidism. The abnormal functioning of the immune system which produces antibodies that attack the thyroid gland, and make it release more thyroid hormones (T3 & T4) into the blood. Thus, this disease is known as a type of hyperthyroidism. Graves' disease is one of the commonest autoimmune disease occurring today, affecting 13 million people of which women are seven times more in number.

Causes of Graves' Disease

The role of the immune system in the human body is to protect the body tissues from foreign invaders such as bacteria and viruses. The immune system produces antibodies and lymphocytes to destroy the foreign bodies. What happens in some people with an autoimmune disorder is that the immune system produces antibodies against the body's tissues itself. In case of Graves' disease, the antibodies produced bind themselves to the surface of the thyroid cells and then stimulate them to secrete more and more thyroid hormones. Excess and continuous secretion causes the thyroid gland to become enlarged. The level of thyroid hormones in the blood also increases causing hyperthyroidism.

The sole reason why the immune system begins to malfunction and produce antibodies that attack the thyroid gland is still unknown. Heredity is one of the factors that leads to this disease. There is no particular gene that triggers this disease. Scientists believe that certain people can inherit immune systems that produce antibodies against healthy cells, but there is no way to find out who will inherit it. This disease is believed to be influenced by both environmental as well as genetic factors. Environmental factors such as stress, infection, steroids, toxins, female sex hormones, iodine intake and so on is believed to cause Graves' disease.

People below the age of 40 are more prone to developing this disease. As compared to men, women are 5-10 times more prone to develop this disease. If a member in the family has this disease, then the other members are likely to get it. Several studies reveal that in the case of identical twins, if one twin contracts this disease, then the other twin is 20% likely to get it also. If smokers are affected by this disease, then they are more likely to be affected by eye problems as compared to non-smokers. Further, people who have other autoimmune diseases can contract Graves' disease.

Symptoms of Graves' Disease

People suffering from Graves' Disease show the same symptoms like that of those suffering from hyperthyroidism, such as:

• Rapid heart rate, palpitations and high blood pressure
• Increased appetite
• Weight loss
• Tremors, nervousness and breathlessness
• Irritability
• Insomnia
• Weak muscles
• Brittle hair and hair loss
• Goiter (enlargement of the thyroid gland) and swollen neck
• Lighter menstrual flow
• Sweating and warm skin
• Diarrhea

Besides the above mentioned symptoms, there are some other symptoms that are distinctive to this particular disease. They are:

Eye Disease
Bulging of the eyes, swelling of the muscles around the eyes, and inflammation of the eyes are seen in patients who have Graves' disease (called Graves' Opthalmology). Protruding eyeballs will release more tears and become red, dry and irritable. These symptoms are not seen in any other type of hyperthyroidism. However, these eye problems do not create permanent damage to the eyes and can be treated and cured by visiting an ophthalmologist. Only a small percent of people suffering from Graves' disease will suffer from these eye problems. Another point to note is that the severity of the disease is not related to the severity of the eye problems. The eye symptoms may actually emerge 6 months before of after the disease has been diagnosed, and are seen more predominantly in patients who smoke.

Skin Disease
Skin disease (pretibial myxedema) is rarely seen in people suffering from Graves' disease. It is a condition in which red lumpy thickening of the skin in front of the shins takes place. The reason why this disease is limited to the lower leg region is still unknown. However, this skin problem is not painful and its severity is not related to the severity of hyperthyroidism.

All the above mentioned symptoms of Graves' disease are curable and doctors either prescribe radioiodine therapy, antithyroid drugs or thyroid surgery for treating this disease. Of the three, radioiodine therapy is the most commonly used treatment in the United States. The symptoms of Graves' disease completely disappear once it is treated.