June is Myasthenia Gravis Awareness Month
Myasthenia Gravis Awareness Month falls in June each year, but the campaign doesn’t end there. It is an important time to recognize the struggles of people with Myasthenia Gravis, more commonly known as MG, a neuromuscular disease that leads to varying degrees of muscular weakness. This month is an important time to empathize with those living with this disease and appreciate the work that is done to raise awareness and funds for research.
What is Myasthenia Gravis?
Myasthenia gravis (my-us-THEE-nee-uh GRAY-vis) is characterized by weakness and rapid fatigue of any of the muscles under your voluntary control. It's caused by a breakdown in the normal communication between nerves and muscles.
There's no cure for myasthenia gravis, but treatment can help relieve signs and symptoms, such as weakness of the arm or leg muscles, double vision, drooping eyelids, and difficulties with speech, chewing, swallowing, and breathing.
Though this disease can affect people of any age, it's more common in women younger than 40 and in men older than 60.
Prevalence
The prevalence of myasthenia gravis in the United States is estimated at 14 to 20 per 100,000 population, with approximately 36,000 to 60,000 cases in the United States. However, myasthenia gravis remains underdiagnosed and the prevalence is probably higher. Previous studies have shown that women are more often affected than men. The most common age at onset is the second and third decades in women and the seventh and eighth decades in men. As the population ages, the average age at onset has increased correspondingly, and now males are more often affected than females, and the onset of symptoms is usually after age 50. A 2015 study in acetylcholine receptor antibody (AChR-Abs) positive Caucasian has demonstrated that there is no specific causal gene for myasthenia gravis there are specific regulatory genes that influence immune regulation. In addition, about 3% of the study population had a primary relative with myasthenia gravis suggesting a small but distinct but not direct genetic influence.
History of Myasthenia Gravis Awareness Month
Myasthenia Gravis Awareness Month is observed every year in June. It’s observed across the country to allow people from the M.G. community to come together and raise awareness about this condition.
M.G. is a neuromuscular disease that causes skeletal muscle weakness in varying degrees. It is an autoimmune disease that affects the neuromuscular junction, causing antibodies to develop that block or destroy the nicotinic acetylcholine receptors, which are found at the junction between nerves and muscles. The breakdown of these receptors prevents muscles from receiving signals from the nerves and contracting accordingly, causing overall muscle weakness.
People affected by this disease find that the most commonly affected muscles are in the eyes, face, and throat, which affects the ability to swallow. Other issues that result from M.G. include drooping eyelids, double vision, difficulty speaking, and difficulty walking. Symptoms include a hoarse voice, fatigue, difficulty walking up the stairs or lifting objects, and facial paralysis.
M.G. is treated with medication including immunosuppressants, neostigmine, and pyridostigmine, which are acetylcholinesterase inhibitors. Surgical intervention may be required in some cases, during which surgeons might remove the thymus of the affected person, which is a lymphoid organ of the immune system.
Diagnosis of this disease requires both a physical and neurological exam to evaluate muscle weakness, movement and sensation, muscle tone, and motor function. If diagnosed, there are treatments that help to manage the symptoms by controlling the immune system response.
Symptoms of Myasthenia Gravis
Muscle weakness caused by myasthenia gravis worsens as the affected muscle is used. Because symptoms usually improve with rest, muscle weakness can come and go. However, the symptoms tend to progress over time, usually reaching their worst within a few years after the onset of the disease.
Although myasthenia gravis can affect any of the muscles that you control voluntarily, certain muscle groups are more commonly affected than others.
Face and throat muscles
In about 15% of people with myasthenia gravis, the first symptoms involve face and throat muscles, which can:
- Impaired speaking. Your speech might sound soft or nasal, depending on which muscles have been affected.
- Cause difficulty swallowing. You might choke easily, making it difficult to eat, drink or take pills. In some cases, liquids you're trying to swallow come out of your nose.
- Affect chewing. The muscles used for chewing might tire halfway through a meal, particularly if you've been eating something hard to chew, such as steak.
- Change facial expressions. For example, your smile might look like a snarl.
Eye muscles
In more than half of people who develop myasthenia gravis, their first signs and symptoms involve eye problems, such as:
- Drooping of one or both eyelids (ptosis)
- Double vision (diplopia), which may be horizontal or vertical, and improves or resolves when one eye is closed
Neck and limb muscles
Myasthenia gravis can also cause weakness in your neck, arms, and legs. Weakness in your legs can affect how you walk. Weak neck muscles make it hard to hold up your head.
When to see a doctor
Talk to your doctor if you have difficulty breathing, seeing, swallowing, chewing, walking, using your arms or hands, or holding up your head.
What Causes Myasthenia Gravis?
Thymus Gland
The thymus gland is a part of your immune system situated in the upper chest beneath your breastbone. Researchers believe that the thymus gland triggers or maintains the production of the antibodies that block acetylcholine.
Large in infancy, the thymus gland is small in healthy adults. In some adults with myasthenia gravis, however, the thymus gland is abnormally large. Some people with myasthenia gravis also have tumors of the thymus gland (thymomas). Usually, thymomas aren't cancerous (malignant), but they can become cancerous.
Antibodies
Your nerves communicate with your muscles by releasing chemicals (neurotransmitters) that fit precisely into receptor sites on the muscle cells at the nerve-muscle junction.
In myasthenia gravis, your immune system produces antibodies that block or destroy many of your muscles' receptor sites for a neurotransmitter called acetylcholine (as-uh-teel-KOH-leen). With fewer receptor sites available, your muscles receive fewer nerve signals, resulting in weakness.
Antibodies can also block the function of a protein called muscle-specific receptor tyrosine kinase (TIE-roh-seen KIE-nays), sometimes referred to as MuSK. This protein is involved in forming the nerve-muscle junction. Antibodies against this protein can lead to myasthenia gravis. Antibodies against another protein, called lipoprotein-related protein 4 (LRP4), can play a part in the development of this condition. Other antibodies have been reported in research studies and the number of antibodies involved will likely expand over time. Some people have myasthenia gravis that isn't caused by antibodies blocking acetylcholine, MuSK or LRP4. This type of myasthenia gravis is called seronegative myasthenia gravis or antibody-negative myasthenia gravis. In general, researchers assume that these types of myasthenia gravis still have an autoimmune basis but the antibodies involved are just not detectable yet.
Other causes
Rarely, mothers with myasthenia gravis have children who are born with myasthenia gravis (neonatal myasthenia gravis). If treated promptly, children generally recover within two months after birth.
Some children are born with a rare, hereditary form of myasthenia gravis, called congenital myasthenic syndrome.
Complications
Complications of myasthenia gravis are treatable, but some can be life-threatening.
Myasthenic crisis
Myasthenic crisis is a life-threatening condition that occurs when the muscles that control breathing become too weak to work. Emergency treatment and mechanical assistance with breathing are needed. Medications and blood-filtering therapies help people to again breathe on their own.
Thymus gland tumors
Some people with myasthenia gravis have a tumor in the thymus gland, a gland under the breastbone that is involved with the immune system. Most of these tumors, called thymomas, aren't cancerous (malignant).
Other Disorders
People with myasthenia gravis are more likely to have the following conditions:
- Underactive or overactive thyroid. The thyroid gland, which is in the neck, secretes hormones that regulate your metabolism. If your thyroid is underactive, you might have difficulties dealing with cold, weight gain, and other issues. An overactive thyroid can cause difficulties dealing with heat, weight loss, and other issues.
- Autoimmune conditions. People with myasthenia gravis might be more likely to have autoimmune conditions, such as rheumatoid arthritis or lupus.
Common Questions About Myasthenia Gravis
Is this myasthenia gravis inherited? Can I pass it on to my children?
Generally, MG is not considered an inherited disease. However, if one family member has an autoimmune disease, it’s not unusual for other family members to also have an autoimmune disease. It is possible for a mother to pass a temporary form of MG to her newborn child. Rarely, the disease does occur in multiple family members.
What is the prognosis with MG?
MG can’t be cured, but it can be treated. Many people with MG can live fairly normal lives. The first one to three years – when various symptoms appear – often are the most difficult. It can take time to work through various treatments to find what works best for you.
MG is called the “snowflake disease” because its symptoms differ for every patient. Symptoms come and go, and periods of remission – when you are symptom-free – are possible. However, there is no way to predict if you’ll achieve remission or how long it will last.
What makes MG worse?
These factors can make your MG symptoms temporarily worse: stress, lack of sleep, illness, overexertion, pain, extreme hot or cold (including outdoor temperatures, hot showers or baths, saunas, hot tubs, hot foods or beverages), and some chemicals (for instance, in insecticides and lawn treatments).
Are there medications I should not take if I have MG?
You should avoid drugs known to make MG symptoms worse, including certain antibiotics, beta-blockers, calcium channel blockers, muscle relaxants, and magnesium. The University of Illinois at Chicago College of Pharmacy offers details. You also can find a list of medications to avoid on the Myasthenia Gravis Foundation of America’s website at www.myasthenia.org.
Be sure to check with your primary MG doctor before taking any new medication, even over-the-counter drugs.
Can I exercise with MG?
The short answer is this: Exercise within your limits is absolutely recommended if you are able. Don’t exercise if you’re weak. Short sessions with breaks are better tolerated than longer sessions.
Start slow with walking or using an elliptical machine, and build gradually as you become stronger. Stop and rest as soon as you feel tired. Have another person with you or bring a cell phone, in case you run into trouble. It’s important to stop short of muscle fatigue, and this point will vary from person to person depending on age, overall fitness level, MG symptoms, and other factors.
Because your symptoms can vary so much from day to day, it’s important to talk with your doctor about how and when to exercise. Together you can set up guidelines on how much exercise is healthy for you and under what circumstances you should attempt it.
What about pregnancy and MG?
If you’re a woman with MG, it’s important to discuss your pregnancy plans in advance with your neurologist whenever possible, so you can work as a team for the best outcomes. You’ll want to discuss how pregnancy can affect your MG, and how MG can affect your pregnancy. Together you can discuss if pregnancy is an option, medications that need to be changed, and risks to the fetus and newborn. You’ll want any pregnancies to be closely monitored.
Should I wear medical alert jewelry? What should it say?
Many myasthenia patients make a personal decision to wear medical alert jewelry such as a bracelet or necklace. At a minimum, a medication card in your wallet or purse should clearly indicate “Myasthenia Gravis” and include your name, date of birth, a family member's telephone number, MG doctor, and medical conditions.
How To Observe Myasthenia Gravis Awareness Month
Share information about MG
Spread information among your friends and family. This month is a great way to encourage people to get diagnosed if they have been feeling unwell.
Share stories from the community
People in the M.G. community come together this month to share their stories and experiences. Share these stories so they reach a wider audience and perhaps someone who needs to hear them.
Host a talk with doctors
It is important to talk about M.G. Work with your community leaders to organize a talk about this lesser-known condition.
Sources:
https://www.mayoclinic.org/diseases-conditions/myasthenia-gravis/symptoms-causes/syc-20352036#:~:text=Myasthenia%20gravis%20(my%2Dus%2D,communication%20between%20nerves%20and%20muscles.
https://www.myastheniagravis.org/about-mg/mg-faq/
https://nationaltoday.com/myasthenia-gravis-awareness-month/