While it is unknown why some people and not others develop the autoimmune reaction that causes Graves’ disease, certain factors make some people more likely to get the disease.

• Females are affected at a rate four to eight times higher than males.
• Graves’ disease tends to affect people most often between the ages of 20 and 40, but it can occur at any time throughout life.
• Some people appear to have a genetic predisposition for developing autoimmune diseases or for thyroid problems. If you have relatives with Graves’ disease or other autoimmune diseases, or relatives with a thyroid condition, you may be at increased risk for developing an autoimmune disease or thyroid condition like Graves’ disease yourself.