MG and Diabetes

There is a complex link between myasthenia gravis (MG) and type 2 diabetes. The body’s immune system plays a role in both MG and diabetes. Research suggests that people with diabetes have an increased chance of developing MG. And people with diabetes may have worse MG symptoms compared to people without diabetes.^1-3

On the other hand, some drugs used to treat MG may increase a person’s chances of developing type 2 diabetes.^1-3

Diabetes as a risk factor for MG

Statistics show people with type 2 diabetes may have a higher risk of developing MG. The exact reason for this is unknown. A 2023 study that looked at a group of people with MG found that about 1 in 4 people with MG also had type 2 diabetes. Most of these people had developed diabetes years before developing MG.¹

MG as a risk factor for diabetes

People with MG have a higher chance of developing type 2 diabetes. One possible reason for this is the use of steroids as a treatment.³

Steroids (corticosteroids) are a type of hormone used to treat many diseases. They are sometimes used to treat symptoms of MG. But steroids can make it difficult to maintain normal blood sugar levels.^3,4

Researchers think that steroids change the way your body responds to insulin. Insulin is an important hormone that controls the amount of sugar in your blood. Steroids can decrease the amount of insulin your body is producing or make you less sensitive to insulin. This causes the amount of sugar in the blood to increase. Extended courses of steroids may increase your chances of developing type 2 diabetes, particularly if you already have other risk factors. ^3,4

For people who already have type 2 diabetes, taking steroids can make it harder to control blood sugar levels. For people without type 2 diabetes, taking steroids may increase the risk of developing type 2 diabetes. Even extended use of steroid cream on your skin may increase your chances of developing type 2 diabetes.^4,5

Dealing with high blood sugar levels

If you notice an increase in your blood sugar levels, talk to your doctor. The possible remedy will depend on the type and amount of steroid that you are taking. As a result, the best treatment options will be unique for each person.⁴

For some people, eating a healthy diet and increasing physical activity can lower blood sugar. But these changes may not be enough. In these cases, doctors may prescribe drugs that can lower blood sugar levels.⁴

Insulin helps your body use the sugar in the blood. Some drugs used to treat high blood sugar try to increase the amount of insulin the body produces. Types of these drugs include:⁴

• Sulfonylureas – One example is gliclazide.
• Glinides – These drugs work fast and for a shorter amount of time than sulfonylureas. This makes them less likely to lower blood sugar too much.

Steroids make your body less sensitive to insulin. This causes sugar to stay in the blood, increasing blood sugar levels. To offset the effect of steroids, certain drugs can be used to increase sensitivity to insulin. These drugs include:⁴

• Metformin
• Thiazolidinediones

Insulin therapy is another option. This involves directly injecting insulin into the body to reduce blood sugar. The amount of insulin and how often it is injected depends on current blood sugar levels and lifestyle.⁴

Depending on your symptoms, your doctor may prescribe steroids as a treatment for MG. In that case, it is helpful to track your blood sugar levels with a blood sugar monitor. High blood sugar can cause many health problems. Tracking your blood sugar will allow you to begin to reduce your blood sugar levels as soon as possible.