ALS and muscular dystrophy both lead to progressive muscle weakness and have no cure. But despite these similarities, they have many differences in other symptoms, causes, and treatment.
Amyotrophic lateral sclerosis (ALS) and muscular dystrophy (MD) both lead to muscle weakness that gets worse over time. Despite this similarity, these are two different conditions.
ALS occurs when nerve cells that control muscle movement are damaged and start to die. With MD, it’s the muscle tissue itself that is damaged and begins to die. As both conditions progress, muscles gradually weaken, affecting movement.
Continue reading below as we compare and contrast the symptoms, causes, and treatment of these two conditions.
ALS and muscular dystrophy symptoms
While ALS and MD do have some symptoms in common, they also have other different symptoms.
ALS symptoms
The first symptoms of ALS can vary from person to person. Some people may initially have symptoms in their arms or legs, while others have the muscles controlling swallowing and speech affected first.
Early symptomsTrusted Source of ALS can include:
twitching muscles, often in the arms, legs, shoulder, or tongue
muscle cramping
muscles that are stiff and tight, called spasticity
muscle weakness
voice changes, such as a more nasal voice or slurred speech
trouble with chewing and swallowing
As ALS progresses, additional symptoms can develop, such as:
increasing difficulty with movement
problems with:
speaking
chewing and swallowing
breathing
changes in thinking and behavior
constipation
weight loss
Muscular dystrophy symptoms
There are over 30 Trusted Source different types of MD. Each type has different characteristics related to symptoms, including when they appear, their severity, and which muscle groups are affected.
Some general symptoms include:
muscle weakness
muscle wasting
trouble with movement and coordination
frequent falls
changes in gait or posture
toe walking
difficulty getting up from a sitting position
scoliosis
heart issues
trouble swallowing
breathing problems
What causes ALS and muscular dystrophy?
ALS and MD also have different causes.
What causes ALS?
It’s not known what exactly causes ALS. In about 10%Trusted Source of people who develop ALS, there’s a family history of the condition. For the remaining 90%, there’s no known family history. This is called “sporadic ALS.”
ALS happens due to damage and death of nerve cells called motor neurons. These are the nerves that control voluntary movement, such as when you walk into the kitchen, pick up a pencil, or swallow your food.
Since these nerve cells effectively pull the strings for voluntary muscle movement, it gets harder and harder to do voluntary movements as ALS progresses.
What causes muscular dystrophy?
MD happens due to genetic changes called mutations. These changes can be inherited from one or both of your parents.
On a basic level, the mutations associated with MD cause muscle fibers to become damaged and die. Over time, this leads to a reduction in muscle function that worsens as time passes.
The two most common types of MD are called Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD).
Both DMD and BMD are caused by mutations in the same gene and almost exclusively affect males. DMD comes on earlier and is more severe than BMDTrusted
Who gets ALS or muscular dystrophy?
Certain things can increase your risk of developing ALS or MD.
ALS risk factors
The risk factors for ALS include:
Age: ALS most commonly develops in people between the ages of 55 and 75Trusted Source.
Sex: Sporadic ALS is more commonTrusted Source in males. There are no sex differences in familial ALS prevalence.
Race: ALS is more common in white people. A 2023 studyTrusted Source found that the prevalence of ALS in white people was almost twice that in Black people.
Genetics: You’re at a higher risk of ALS if a close family member, such as a parent or sibling, has it.
Environmental factors: Several environmental factors have been linked with an increased risk of ALS, including:
smoking
military service
injuries affecting the brain or spinal cord
exposure to certain toxins
electric shock
viral infections
excessive exercise
Muscular dystrophy risk factors
MD happens due to genetic changes that are inherited. Your risk increases if other people in your family have received a diagnosis.
Certain types of MD happen almost exclusively in males. This is because they’re inherited in an X-linked recessiveTrusted Source manner. Because males typically have one X chromosome, they’re much more likely to be impacted by these types of MD.
The age of onset can also vary between MD types. For example, DMD typically presents in younger children before age 5Trusted Source. Meanwhile, the symptoms of BMD do not often develop until later on, sometimes into adulthood.
When to contact a doctor
It’s a good idea to contact a doctor if you’re experiencing unexplained muscle weakness. This is especially true if it’s persistent or gets worse as time passes.
There are many conditions that can lead to muscle weakness. While your symptoms may not be due to ALS or MD, they may be happening because of another condition that needs to be addressed.
How do doctors diagnose ALS and muscular dystrophy?
If you see a doctor for muscle weakness or other symptoms, they’ll start by asking about:
your symptoms
your personal and family medical history
any medications or supplements you’re taking
They will perform a physical exam. They’ll also test your muscle strength, reflexes, and movement.
If your doctor suspects ALS or MD, additional tests can be ordered to help rule out other conditions. These include:
tests on blood, urine, or cerebrospinal fluid (CSF)
genetic testing
electromyography and nerve conduction studies, which look at how your nerves and muscles are functioning
analysis of a muscle biopsy
imaging tests like MRI scan or CT scan
How are ALS and muscular dystrophy treated?
There’s no cure for ALS or MD. Treatment is aimed at managing symptoms, slowing progression, and improving quality of life.
ALS treatment
Some medications are approved by the Food and Drug Administration (FDA) for ALS. These can help to reduce damage to motor neurons and slow ALS progression. They include:
edaravone (Radicava)
riluzole (Exservan, Rilutek, Tiglutik)
tofersen (Qalsody), which is used in people with ALS with changes in the SOD1 gene
Medications may also be used to manage symptoms that happen due to ALS, such as muscle cramping or spasticity, pain, and emotional symptoms.
People with ALS also need increasing levels of assistance with daily activities. Things that can help out with this include:
physical therapy
occupational therapy
speech-language therapy
assistive devices for mobility, speech, and daily activities
nutritional support, including a feeding tube when a person with ALS can no longer swallow safely
respiratory support through non-invasive ventilation or mechanical ventilation when breathing is affected by ALS
ALS is progressive, meaning symptoms worsen as time passes. According to the Centers for Disease Control and Prevention (CDC)Trusted Source, most people with ALS live 3 to 5 years after their symptoms start.
Muscular dystrophy treatment
Some medications are also available for MD. Corticosteroids can be given to help slow down MD progression.
There are also some specific gene therapies that are FDA-approved for the treatment of DMD. These include eteplirsen (Exondys 51) and golodirsen (Vyondys 53).
As in ALS, many people with MD will need assistance in their daily lives. Some interventions that can help with this include:
physical therapy
occupational therapy
speech-language therapy
assistive devices to help with posture support, mobility, and doing daily activities
respiratory support through breathing exercises or ventilation
Some people with MD may also develop contractures, which are when muscles or tendons around a joint shorten. Surgery can help to release contractures.
While all types of MD are progressive, outlook depends on the specific type of MD that a person has. Some types progress more rapidly, leading to disability and death, while others are milder.
Can you prevent ALS or muscular dystrophy?
There’s no way to prevent ALS or MD. However, both conditions can benefit from early diagnosis and treatment. It’s important to see a doctor if you start to have symptoms of either condition.
It’s also never a bad idea to adopt healthy lifestyle changes. While these may not prevent ALS or MD, they can boost your overall health and lower the risk of other chronic conditions. Consider:
eating a healthy, balanced diet
engaging in normal levels of physical activity regularly
getting enough sleep at night
reducing stress
limiting alcohol consumption
quitting smoking
taking steps to manage other underlying health conditions
Frequently asked questions about ALS and muscular dystrophy
Is ALS neurological or muscular?
ALS is a neurological condition. However, the effects of ALS impact the function of your muscles.
What’s the difference between muscular dystrophy, ALS, and MS?
These three conditions have different causes and effects on the body. MD and ALS happen due to damage and death of muscle tissue and motor neurons, respectively.
MS is an autoimmune disease where your immune system attacks myelin, the protective covering on some nerve cells. As with MD and ALS, people with MS may experience muscle weakness and problems with movement.
Can you have multiple sclerosis and muscular dystrophy at the same time?
Yes, although this is rare. A 2018 case studyTrusted Source reported on a person who had MS and limb-girdle muscular dystrophy at the same time.
Takeaway
Both ALS and MD lead to muscle weakness. However, these two conditions have many differences in other symptoms, causes, and how they’re treated.
ALS happens when motor neurons that control voluntary muscle movement become damaged and die. Its exact cause is unknown. Meanwhile, MD is caused by genetic changes that cause muscle fibers to break down.
There’s no cure for ALS or MD. However, early diagnosis and treatment can help to manage symptoms, slow progression, and boost quality of life. If you notice that you have unexplained muscle weakness, make an appointment with a doctor.
Recourses:
https://www.healthline.com/health/is-als-a-form-of-muscular-dystrophy