Muscular Dystrophy

A group of genetic disorders (more than 30) that cause muscle weakness and other muscle-related symptoms is called muscular dystrophy. The symptoms that appear in people with these disorders often worsen over time. While some types of muscular dystrophy are present at birth (congenital), others may happen later in life.

Furthermore, these health conditions are a type of myopathy, which negatively affects the skeletal muscles. Muscular dystrophy can affect multiple muscles in the body, including those that help the heart and lungs function properly.

In general, these disorders are rare in the U.S. They affect about 16 to 25 people per 100,000. One of the most common types of muscular dystrophy in children is Duchenne muscular dystrophy, and myotonic dystrophy in adults.

Types of Muscular Dystrophy

While there are more than 30 types of muscular dystrophy, you can find the most common of them in the list below. For example:

DMD (Duchenne muscular dystrophy) – This is one of the most common types of muscular dystrophy. It mostly affects boys, but girls may also develop it. In more advanced stages, DMD negatively affects the function of the lungs and heart muscle.
BMD (Becker muscular dystrophy) – This is another common type of muscular dystrophy that causes symptoms in people aged from 5 to 60. In most cases, people develop symptoms during their teen years, and the severity of the symptoms varies among people with BMD.
Myotonic dystrophy – This is one of the most common types of muscular dystrophy that negatively affects adults. It affects both men and women and can cause endocrine problems (such as thyroid disease and diabetes) as well as heart and lung issues.
CMDs (congenital muscular dystrophies) – This type of muscular dystrophy is present at birth and causes overall muscle weakness. Sometimes, it may also cause joint stiffness or looseness. In more severe cases, people may also develop scoliosis, breathing problems, intellectual or learning disabilities, seizures, or eye disorders.
Distal muscular dystrophy – This form affects the muscles of the feet, hands, and lower arms and legs. Usually, it occurs in people between the ages of 40 and 60.
EDMD (Emery-Dreifuss muscular dystrophy) – Most of the time, this type of muscular dystrophy affects male children and young adults. It causes muscle weakness in the shins, upper arms, and shoulders. Without treatment, it may also cause heart problems.
FSHD (facioscapulohumeral muscular dystrophy) – People who develop this type often experience problems with the muscles in the face, but may also have problems with the muscles in the upper arms and shoulders. In most cases, the symptoms appear before the age of 20. About 4 out of 100,000 people have FSHD in the U.S.
LGMD (limb-girdle muscular dystrophy) – People with this type of muscular dystrophy have problems with the upper legs, shoulders, and hips. It may occur at any age, and about 2 out of 100,000 people have LGMD in the United States.
OPMD (oculopharyngeal muscular dystrophy) – People with OPMD often have problems with the muscles in the throat and eyelids. The most common symptoms include dysphagia (swallowing problems) and ptosis (drooping eyelids). Typically, it occurs between the ages of 40 and 50, and it affects about 1 in 100,000 people in the U.S.

What Are The Symptoms of Muscular Dystrophy?

The symptoms of this condition are often different among people because they depend on several factors. These include the type and severity of the disease, gender, age, and existing health problems. While the main symptom of muscular dystrophy is muscle weakness, it may also cause other symptoms. Check some examples below:

Spasticity
Contractures (permanent tightening of the muscles, skin, and tendons)
Pain
Irregular walking gait
Joint stiffness or looseness
Walking problems
Difficulty running or climbing stairs
Dysphagia (swallowing problems)
Learning disorders
Intellectual or learning disabilities
Scoliosis (also known as curved spine)
Heart problems (including cardiomyopathy, arrhythmia, and others)
Extreme tiredness (fatigue)

Most of the time, the symptoms of this disorder are mild and worsen over time. If any of the previous symptoms happen, immediately contact your healthcare professional. Otherwise, it may lead to permanent damage.

Causes

This is a genetic disorder that occurs due to changes (mutations) in specific genes that are responsible for healthy muscle structure and function. When mutations in the genes occur, it leads to progressive muscle weakness. Normally, there are several genes that play an important role in muscle function. That’s why there are multiple types of this condition. While most diagnosed cases occur due to inherited genetic mutations from one of the biological parents, it may occur due to new gene changes. Check some ways you can inherit this disorder below:

Recessive inheritance – In this case, you will inherit the abnormal genes from both biological parents. There are some forms of LGMD that have this inheritance.
Dominant inheritance – In such cases, it is enough to get only one abnormal gene to develop this disorder. Usually, myotonic, fascioscapulohumeral, and oculopharyngeal muscular dystrophies have this type of inheritance.
X-linked inheritance – In normal circumstances, a male has one X and one Y chromosome, but a female has two X chromosomes. Commonly, an X-linked disorder occurs when the only X chromosome you have is mutated. That’s why females develop only mild forms of muscular dystrophy. Becker and Duchenne muscular dystrophies have this form of inheritance.

Is There a Way to Prevent Muscular Dystrophy?

Unfortunately, it is not possible to prevent this disorder because it occurs when certain abnormal genes are passed from the biological parents to their children during pregnancy. However, you can perform some genetic tests before becoming pregnant to check for these abnormal genes.

Furthermore, once you are diagnosed with this condition, physicians may recommend the following tips to ease the symptoms, reduce the progression of the disease, and improve your quality of life. Check some examples below:

Regularly perform physical exercise according to the doctor’s recommendations
Try to get and maintain a healthy weight
Adopt a healthy diet to prevent malnutrition
Drink plenty of fluids to reduce the risk of dehydration and constipation
Stop smoking – If you have problems with smoking cessation, discuss it with your healthcare professional.
Vaccination

Diagnosis

Doctors usually start the diagnosis of muscular dystrophy with a physical and neurological examination to check for irregularities associated with this genetic disease. They may also ask some questions about your medical and family history and symptoms. However, to exclude other health conditions that cause similar symptoms and confirm muscular dystrophy, doctors often perform the following tests and procedures. These include:

Genetic tests – To perform this test, doctors will take a sample of blood to check it for the abnormal genes associated with muscular dystrophy.
Muscle biopsy – During this test, physicians will take a sample of the affected muscle to check it under a microscope for muscular dystrophy signs.
Electromyography (EMG) – This test helps doctors measure the electrical activity of the muscles and nerves.
Creatine kinase blood test – Typically, the muscles release a substance called creatine kinase when they are damaged. Increased levels of this substance may indicate muscular dystrophy.

Treatment

Nowadays, there is no way to cure this genetic disorder. That’s why the treatment goal is to ease the symptoms, slow down the progression of the disease, and improve your quality of life. Check the most common treatments used to treat muscular dystrophy below:

Physical and occupational therapies – These therapies are often recommended by doctors to strengthen the muscles and maintain movement function.
Corticosteroids – This group of medicines is primarily used to reduce inflammation and delay muscle weakness. They may also help improve lung function, slow the progression of cardiomyopathy, and others. Doctors often prescribe Prednisolone and Deflazacort.
Mobility aids – These include canes, braces, walkers, and wheelchairs.
Surgery – people often need surgery to reduce tension in the contracted muscles or treat scoliosis.
Heart medicines – Most of the time, healthcare professionals prescribe beta-blockers and ACE inhibitors to treat cardiomyopathy and prevent heart failure. Sometimes, people require pacemakers to treat irregular heart rhythm (arrhythmia) and heart failure.
Speech therapy – It is often used to improve dysphagia in people with muscular dystrophy as well as other disorders.
Respiratory care – For example, assisted ventilation and tracheostomy.

Additionally, there are some medicines that may improve certain types of the disease. These include Eteplirsen and Golodirsen.

Frequently Asked Questions

What is the life expectancy of muscular dystrophy?

Usually, the life expectancy of people with this genetic disorder is different because it depends on a few factors. These include the severity and type of muscular dystrophy, gender, overall health, your response to treatment, and age. For instance, people who develop DMD often die from this disease by the age of 25.

When should I see my healthcare provider?

If you or your child experiences symptoms that resemble muscular dystrophy, you should see a doctor right away. People who are already diagnosed with muscular dystrophy should inform their doctors about any changes that they notice.

What is the prognosis for muscular dystrophy?

The prognosis is different because it depends on which type of this genetic disorder you develop. If you have additional questions, ask your healthcare provider.