Causes and Risk Factors of Thyroid Eye Disease

Thyroid eye disease is caused by an overactive thyroid (hyperthyroidism) that occurs because of Graves’ disease. You may also see thyroid eye disease called Graves’ eye disease, Graves’ orbitopathy, and Graves’ ophthalmopathy.

It is likely that a combination of different genetic, lifestyle, and environmental factors are responsible for someone developing thyroid eye disease.

Common Causes

Thyroid eye disease happens because of Graves’ disease, which causes hyperthyroidism. Graves’ disease is an autoimmune disorder, which means your immune system attacks your own body.

If you have Graves’ disease, your immune system creates an antibody (type of protein) called thyroid-stimulating immunoglobulin (TSI). TSI affects your thyroid's production of hormones, which causes it to be overactive. An overactive thyroid, called hyperthyroidism, makes too much thyroxine hormone.

Graves’ disease can also cause your immune system to make antibodies that attack the muscles and tissues of your eyes. The antibodies can affect different parts of the eyes and cause a variety of symptoms.

The antibodies may attack the cells of your eyes because they are targeting specific proteins mistakenly. For example, if you have too much of a protein called insulin-like growth factor 1 receptor (IGF-1R), then you are more likely to have antibodies attack your eyes' cells.

Not everyone with thyroid eye disease has too much IGF-1R, so researchers continue to study what causes this condition.

Genetics

Since family history increases the risk of having Graves’ disease and thyroid eye disease, it is possible for genetics to play a role in developing these conditions. This means if one of your close family members has thyroid eye disease, then you are more likely to get it because it may be passed down.

You are also more likely to have thyroid eye disease if you have close family members who have other types of autoimmune conditions. It may be possible for a person to inherit the risk of having an autoimmune disorder.

Although researchers believe genetics are involved, it is not clear which genes are responsible for someone having thyroid eye disease. They suspect that variations in the following genes may play a role, but they are not the only ones involved:

• HLA-DRB1 
• PTPN22 
• TG 
• TSHR

It is also possible that the genes involved in regulating the immune system may have mutations that cause Graves’ disease and thyroid eye disease.

Mutations are changes in the DNA that can cause problems to develop. Your DNA has instructions that code for proteins that are responsible for the processes inside your body, such as cell growth and division. If a mutation occurs that affects your immune system, it may cause it to create antibodies that attack your eyes' cells. 

Lifestyle Risk Factors

Researchers believe some lifestyle factors may increase your risk of developing thyroid eye disease.

Other lifestyle factors that may affect thyroid eye disease development include:

• Changes in hormones 
• Having infections
• Taking certain medications, such as amiodarone for heart disease 
• Not having enough or having too much dietary iodine 

Smoking 

Smoking is an important lifestyle risk factor for developing thyroid eye disease that you can control. In general, smoking increases your risk of having thyroid eye disease. It can also make your symptoms worse and cause more severe eye problems.

Talk to your healthcare provider if you are having problems quitting smoking and need additional help. 

Stress  

Stress is another lifestyle factor that you can control. It can have a negative impact on your health and may increase the risk of getting thyroid eye disease. 

To control stress, you may need to: 

• Eat a healthy diet
• Exercise regularly
• Get enough sleep 
• Meditate 
• Try yoga or other relaxing activities 
• Start a hobby like painting 
• Find time to relax on a regular basis

A Word From Verywell

Researchers are still studying thyroid eye disease, but they know that hyperthyroidism and Graves’ disease cause this condition. This means it is important to talk to your healthcare provider if you suspect you have a thyroid problem and get treatment right away. 

Delaying treatment or not following your healthcare provider's instructions for taking medications can increase your risk of getting thyroid eye disease. If you are having trouble complying, talk to your healthcare provider and reach out to friends or family for support. 

There are some lifestyle factors, such as smoking and stress, that you can control. Consider joining a support group if you need additional help.