Amyotrophic Lateral Sclerosis (ALS) vs. Multiple Sclerosis (MS)

Amyotrophic lateral sclerosis (ALS) and multiple sclerosis (MS) both have “sclerosis” in their names, but they are different conditions with varying causes, symptoms, and treatments.

ALS is a progressive disease of the motor neurons, the nerve cells that control motion in the body. It causes changes in how people move, talk, and breathe.

MS is an autoimmune disease caused by lesions (damage) on the brain, spinal cord, or optic nerves. Symptoms of MS vary based on where the lesions are located and can include problems with movement, memory issues, vision loss, and numbness or tingling.

Mass General Brigham Neuroscience Institute researchers study ALS and MS, finding new treatments, developing better diagnostic tools, and improving quality of life for people with neurological conditions. In this article, Sabrina Paganoni, MD, PhD, and Howard L. Weiner, MD, describe both conditions, how they’re similar, and how they’re different. They share promising advances in research for both ALS and MS.

Dr. Paganoni is a physical medicine and rehabilitation specialist and leads ALS clinical trials at the Sean M. Healey and AMG Center for ALS at Massachusetts General Hospital. Dr. Weiner is a neurologist and co-director of the Center for Neurologic Diseases at Brigham, where his research lab studies MS and other diseases.

What is ALS?

ALS is a disease that impacts nerve cells that control movement in the body. It’s a progressive disease, meaning symptoms continue to get worse over time. Also known as Lou Gehrig’s disease, ALS can affect how people move, talk, and function day to day.

Symptoms of ALS

ALS affects the nerves that control movement in the body, which can cause a variety of symptoms including:

• Muscle twitches or cramps
• Tight muscles
• Weak muscles
• Difficulty chewing, swallowing, breathing, or talking

As the disease progresses, people who have ALS may lose the ability to stand or walk on their own. Eventually if the ability to breathe independently is lost, a respirator (breathing machine) may help people with ALS breathe.

Diagnosis of ALS

Your doctor diagnoses ALS with a combination of taking your medical history, doing a physical and neurological exam, getting imaging or nerve and muscle tests (often referred to as “EMG”), doing a genetic test when appropriate, and ruling out other conditions.

"A physician with expertise in ALS can diagnose your condition more quickly,” says Dr. Paganoni. “Early diagnosis is important to be able to start treatment to slow disease progression and control symptoms, and to access research options.”

Early diagnosis also lets you start physical therapy, speech therapy, and respiratory therapy to maintain quality of life as long as possible.

Treatments for ALS

Treatments for ALS include medications that slow disease progression or manage symptoms.

There is no cure for ALS yet, but researchers are working hard to find better treatments and a cure. Your care team helps craft the right treatment plan for you based on your symptoms, disease progression, lifestyle, and goals.

“Our goal with a treatment plan is to maintain function and quality of life,” says Dr. Paganoni. “Medications and therapy can slow disease progression and help control symptoms, giving people more time.”

Physical and occupational therapy, speech therapy, and respiratory therapy can help you maintain your quality of life for longer and make day-to-day tasks easier. An ALS exercise plan tailored to your symptoms can help you maintain function for longer.

What is MS?

MS is a disease of the central nervous system—the brain, spinal cord, and optic nerves—that progresses over time. MS is an autoimmune condition, meaning that the body mistakenly attacks its own healthy cells.

MS causes the body's immune response to destroy myelin, a fatty cover that surrounds nerve cells, and the nerves beneath. As the damage gets worse, the functions of those nerves—like walking, balance, or vision—are impacted.

Your disease path and symptoms depend on the type of MS you have. Some people will have relapses and periods of remission—periods of time with no symptoms—while others will have steadily worsening symptoms.

Symptoms of MS

MS symptoms vary based on the location of the lesions, the progression of the disease, and other individual factors.

Early symptoms of MS may include:

• Trouble walking
• Vision problems
• Muscle weakness or tremors
• Numbness or tingling

You may experience other symptoms like depression, sexual dysfunction, or fatigue. Each person’s MS experience is different.

Symptoms like weakness, spasms and cramps, and fatigue can be severe enough that you need assistance with everyday activities or need an assistive device like a wheelchair, cane, or walker.

Diagnosis of MS

Your doctor diagnoses MS by taking a detailed medical history, doing a physical and neurological exam, getting imaging tests like an MRI, and potentially doing a lumbar puncture (also called a spinal tap) to test your spinal fluid.

“There’s no single test for MS,” says Dr. Weiner, “so your doctor will use the various tests to better understand your symptoms and rule out similar conditions. Their experience treating MS can help you get a diagnosis quickly and move forward to discuss treatment options.”

Treatment for MS

Treatments for MS include disease-modifying treatments (DMTs), symptom management through medication or lifestyle changes, and supplements and integrative medicine. A healthy diet and regular exercise can help reduce inflammation in the body and help maintain mobility.

“DMTs are important in managing MS. They slow disease progression and reduce the frequency and severity of relapses,” says Dr. Weiner. “But they’re not the only option for patients with MS. Symptom management can make every day a little easier.”

Like ALS, there is no cure for MS, but researchers are investigating new treatments and a path to a cure.

What is sclerosis?

Sclerosis is scarring or hardening of nerve cells as they’re damaged.

In ALS, sclerosis happens on the motor nerves as they’re damaged and ultimately lost. In MS, sclerosis appears as lesions on the brain, spinal cord, and optic nerves caused by the body attacking the myelin on the nerves.

While they both have sclerosis in the name, each condition shows differently in the body based on how and where the scarring occurs.

Can you have ALS and MS at the same time?

It’s possible to have both conditions, but it’s extremely rare.

“MS and ALS develop differently,” says Dr. Paganoni, “but some symptoms may overlap which is why it’s important to be evaluated by specialists who can help differentiate between the two.”

It’s possible to be misdiagnosed with one disease when you have the other. Overlap in some symptoms—like tremors, muscle weakness, or fatigue—can make MS and ALS appear similar.

“Finding a neurologist with experience diagnosing and treating MS or ALS is important,” says Dr. Weiner. “Their expertise will help you get the correct diagnosis faster.”

Is ALS more serious than MS?

There are several types of MS, some more aggressive than others. However, life expectancy for someone with MS tends to be long.

“You can live with MS for 25 or 30 years—or more—depending on what age you are diagnosed,” says Dr. Weiner.

ALS, on the other hand, is a fast-moving condition. People with ALS tend to get worse over time.

“At this time, people with ALS live an average of 3 to 5 years after they first recognize symptoms, though every person is unique,” says Dr. Paganoni. “Some people live longer, and progress is being made every day to help extend the lifespan and quality of life for people with ALS.”

Research for ALS and MS

At the Mass General Brigham Neuroscience Institute, researchers are redefining what’s possible in brain and nervous system care. Our work focuses on improving patient outcomes and advancing scientific discovery. The Neuroscience Institute fosters collaboration across disciplines and accelerates the path from research to patient care.

With over 400 active clinical trials in neuroscience, researchers are working to find better treatments for ALS and MS and hope to eventually find cures for the conditions.

Recent research has included:

• Foralumab for MS: A nasal spray that helps reduce inflammation and improves symptoms
• The HEALEY ALS Platform Trial: A collaboration with ALS researchers across the country to test new drugs for ALS treatment to bring them to patients faster
• New imaging technology to better understand MS: Improved diagnostic images to help neurologists better diagnose MS and lead to more effective treatments
• Clinical trials, new medications, and brain implants for ALS: Trials for symptom management, new treatments, and supportive devices to improve the quality of life for people with ALS

“There are good treatments available today to improve quality of life and slow disease progression for ALS and MS,” says Dr. Weiner.

Dr. Paganoni adds, “Researchers are working every day to improve treatments, expand availability, and help people with these conditions.”