Myasthenia Gravis (MG): What You Need To Know

Myasthenia gravis (MG) is a neuromuscular condition that causes weakness in the skeletal muscles, which are the muscles your body uses for movement. It happens when communication between nerve cells and muscles becomes damaged. This impairment hinders crucial muscle contractions from happening, leading to muscle weakness.

According to the Myasthenia Gravis Foundation of America, MG is the most popular primary disorder of neuromuscular transmission. It’s a relatively rare disorder that affects between 14 and 20 out of every 100,000 people in the United States.

What causes myasthenia gravis?

Myasthenia gravis is a neuromuscular disorder that’s usually caused by an autoimmune problem. Autoimmune disorders occur when your immune system mistakenly attacks your healthy tissue. In this disease, antibodies, which are proteins that normally attack foreign, harmful substances in the body, attack the neuromuscular junction. Damage to the neuromuscular membrane decreases the effect of the neurotransmitter substance acetylcholine, which is an important substance for sending information between nerve cells and muscles. This results in muscle weakness.

The major cause of this autoimmune reaction is unclear to experts. According to the Muscular Dystrophy Association, one theory is that a particular viral or bacterial protein may trigger the body to attack acetylcholine.

According to the National Institutes of Health, Myasthenia gravis usually occurs in people over the age of 40. Women are more susceptible at a younger age, while men are more susceptible at 60 or older.