ALS vs. MS Differences and Similarities

Medically Reviewed on 8/4/2022
Woman receiving assistance standing up.
Both MS and ALS are disabling.
  • ALS (amyotrophic lateral sclerosis, Lou Gehrig’s disease) and MS (multiple sclerosis) are not the same disease. They sometimes are confused because they have some similarities. However, they have more differences than similarities.
  • MS is a neurodegenerative disease that results in the destruction the protective coating (myelin sheath) on nerves of the CNS (central nervous system), which causes a faulty relay of instructions from the brain to the body. Many people may have mild symptoms for years with periods of remission. In contrast, ALS destroys the nerve cells (neurons) so that the body cannot communicate with the brain. Symptoms of ALS progress continually, and result in paralysis, and death a few years after the initial diagnosis.
  • The similarities between these two conditions are that both MS and ALS are so-called neurodegenerative diseases that affect the brain and spinal cord (central nervous system or CNS). Both affect the body's muscles and nerves.
  • ALS and MS have no known cure.

What are the main differences between MS vs. ALS?

  • Multiple sclerosis is an autoimmune disease, while ALS is hereditary in one out of 10 people due to a mutated protein.
  • MS has more mental impairment and ALS has more physical impairment.
  • Late stage MS rarely is debilitating or fatal, while ALS is completely debilitating leading to paralysis and death.
  • The age of diagnosis of MS usually is between age 20 and 50; rarely, it can occur in children and teens.
  • MS is more common in women and ALS is more common in men.

What are the differences between the symptoms and signs of MS vs. ALS?

Multiple sclerosis symptoms and signs

  • Numbness and tingling in the body
  • Vision problems
  • Sexual dysfunction
  • Bowel problems
  • Depression
  • Mood swings
  • Fatigue, often when warming up to exercise
  • Slowed or fuzzy memory (cognitive problems)
  • Mild problems walking
  • Periods with few symptoms followed by relapses

ALS (Lou Gehrig's disease symptoms and signs

  • Muscle cramps
  • Trips and falls easily
  • Clumsiness
  • Problems holding the head up

SLIDESHOW

What Is Multiple Sclerosis? MS Symptoms, Causes, Diagnosis See Slideshow

What are the causes of MS vs. ALS?

ALS is not considered an autoimmune disease, although some researchers theorize that it might be, due in part, to a disorganized immune response. Hereditary factors such as genes are thought to play a significant role in some patients because about one of every 10 patients has inherited the disease. However, nine of 10 patients seem to have a spontaneous mutation in their genes that causes production of an unusual protein (ubiquilin2) that is speculated to play a significant role in the cause of the disease. Scientists don't know what triggers the onset of ALS. However, researchers suggest that a chemical imbalance (high levels of glutamate, a chemical messenger) also may play a role in causing the disease. In addition, researchers have noticed that members of the military have a much higher rate of ALS than the non-military population, but the cause of this statistical finding is unknown.

MS is considered to be an autoimmune disease, although we do not know what triggers it. However, we know what occurs in the body. The body perceives myelin (a substance that coats nerve cells that allows them to function optimally) as a foreign substance and begins to destroy it. This results in intermittent and/or poor functionality of nerve cells in the brain and spinal cord, that in turn, cause MS symptoms.

Do MS and ALS have the same risk factors?

Age is risk factor for both ALS and MS, but ALS usually is diagnosed in older individuals (aged about 40 to 70), with an average age of onset of 55. While MS is diagnosed in a younger population (aged 20 to 50).

ALS is more common in men by about 20%, while MS is about two to three times more likely to develop in women. Heredity plays a significant role in some individuals that develop ALS (about 10%). MS is not considered to be a hereditary disease, but new data may modify this conclusion.

In addition, being a member of the military raises the risk (twice as likely) of developing ALS. However, military service is not considered a risk factor for MS.

If you have an identical twin with MS, there is a 30% chance for you to develop MS.

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How do doctors diagnose MS and ALS?

If the history, symptoms, and physical exam suggest that ALS is a possible diagnosis, the patient is usually referred to a neurologist and given an electromyogram (EMG) to test muscle and nerve function. If these functions are not normal, an MRI of the spinal cord and brain is typically ordered. Some patients will also have a spinal tap and blood tests to help exclude other diseases. The diagnosis of ALS is by exclusion. This means that ALS is diagnosed after other possible diseases have been ruled out. A neurology consultant specialist usually does this diagnosis.

The same methods are used to diagnose MS. Moreover, like ALS, multiple sclerosis is a diagnosis of exclusion (proving that other conditions are not the cause of symptoms). However, MS has two additional diagnostic components that most neurologists to diagnose MS. The first is evidence of damage in the central nervous system in two separate areas (for example, MRI findings of damage in the brain, spinal cord, and/or optic nerve), and the evidence that the damage occurred at two different points in time.

Treatment options

Treatments for ALS cannot reverse the nerve damage, but they can only slow progression of disease. The US FDA has approved two drugs for the treatment of ALS-riluzole (Rilutek) and edaravone (Radicava).

MS treatment is not a cure for multiple sclerosis. Treatments may help speed recovery from an MS exacerbation of symptoms and may slow the progression of the disease. Although a few patients may have mild symptoms, and not require treatment. Treatments for MS attacks can include corticosteroids and plasma exchange (plasmapheresis, in which the liquid portion of your blood is removed, treated, and returned to the body). For progressive recurrent MS, ocrelizumab (Ocrevus) is the only FDA-approved therapy. There are a number of other drugs for relapsing-remitting MS that may be prescribed by a neurologist to help reduce symptoms.

Treatment protocols for ALS and MS are best determined by your individual situation. Treatments are best determined in consultation with your primary care physician and a consultant such as a neurologist.

What are treatments for symptoms of MS vs. ALS?

Treatments for ALS cannot reverse the nerve damage, but they can only slow progression of disease. The US FDA has approved two drugs for the treatment of ALS-riluzole (Rilutek) and edaravone (Radicava).

MS treatment is not a cure for multiple sclerosis. Treatments may help speed recovery from an MS exacerbation of symptoms and may slow the progression of the disease. Although a few patients may have mild symptoms, and not require treatment. Treatments for MS attacks can include corticosteroids and plasma exchange (plasmapheresis, in which the liquid portion of your blood is removed, treated, and returned to the body). For progressive recurrent MS, ocrelizumab (Ocrevus) is the only FDA-approved therapy. There are a number of other drugs for relapsing-remitting MS that may be prescribed by a neurologist to help reduce symptoms.

Treatment protocols for ALS and MS are best determined by your individual situation. Treatments are best determined in consultation with your primary care physician and a consultant such as a neurologist.

Is there a cure for MS or ALS?

Currently, there is no cure for ALS or MS. However, in consultation with your primary care physician and a consultant (usually a neurologist), there are treatment protocols to help slow the progression of these diseases, and there are medications to reduce their symptoms.

What is the life expectancy for MS vs. ALS?

In general, the prognosis for MS is much better than for ALS. People with MS may have a lifespan that is relatively normal but is about 6-7 years shorter than in those without the disease. Depending upon the response to treatment and the presence of complications, the prognosis for MS patients may range from good to poor. In contrast, the life expectancy of a person with ALS is only about 2-5 years after the time of diagnosis, although about 20% may live somewhat longer than five years. ALS progresses more rapidly than MS, and because nerve cells are the targets that become damaged, the prognosis is at best, fair to poor.

Medically Reviewed on 8/4/2022
References
ALS Association. "Criteria for the Diagnosis of ALS." <http://www.alsa.org/als-care/resources/publications-videos/factsheets/criteria-for-diagnosis.html>.

National Multiple Sclerosis Society. "Diagnosing MS." <http://www.nationalmssociety.org/Symptoms-Diagnosis/Diagnosing-MS>.