A slowing and unsteady gait would be unusual for a young or middle-aged adult. It would certainly be a sign to call the doctor to be checked for illness. Could it be multiple sclerosis (MS) or amyotrophic lateral sclerosis (ALS)? Both have similar names, but are they similar diseases? Do they have similar outcomes?
In fact, while both ALS and MS can affect balance and mobility, they are two distinct neurodegenerative diseases. The causes of each, who is affected, and their progression, symptoms, treatments, and prognoses are also quite different.
Amyotrophic lateral sclerosis (ALS) or motor neuron disease is also called “Lou Gehrig’s disease” after the mighty baseball player for the New York Yankees whose career was cut short by the progressive, neurodegenerative disease. The ALS Association describes ALS as a progressive condition that affects cells in the brain and spinal cord. The motor neurons that signal and control muscles degenerate, leading to muscle weakness and loss of movement. As the nerves in the spinal column degenerate, this leads to scarring and hardening (“sclerosis”) within the spine.
Alternatively, multiple sclerosis (MS) is an inflammatory autoimmune disease. The immune system attacks the protective coating of the nerve fibers (a substance known as myelin), causing permanent scarring, or sclerosis, of the brain and spinal cord.
One disease causes motor neuron degeneration (ALS) and the other causes inflammation (MS). Both cause hardening (or sclerosis), but that occurs by two completely different processes.
There are varying profiles of people who are diagnosed with ALS or MS, and there are some patterns for each. Having all of the characteristics of the profile does not mean that you will get the disease. However, if you fall within one of these categories, it may help doctors pinpoint the cause of your symptoms and create a treatment plan faster.
Men are 20 percent more likely to develop ALS than women before age 65. As they age, women become as likely as men to receive the diagnosis. The average age at the time of diagnosis is 55. In the U.S., white people comprise almost 75 percent of ALS cases.
If you've completed military service, that might also be a risk factor for amyotrophic lateral sclerosis. While there is no scientific proof why former members of the military are diagnosed with a higher frequency of ALS, there is suspicion that it could be linked to head trauma, extreme physical exertion, or exposure to lead, toxic chemicals, or pesticides.
Nearly 1 million people in the United States have multiple sclerosis. Women are three times more likely than men to have relapsing-remitting MS. (The gender split is about even for those who have primary progressive MS.) Most people with MS are diagnosed between the ages of 15 and 50. People of all ethnicities can develop MS, however, white people of northern European ancestry have the greatest frequency.
The causes of both ALS and MS are unknown, but genetics can play a factor in both diseases. As many as 10 percent of ALS cases are “familial ALS” and are inherited through a gene mutation. According to the Mayo Clinic, if someone has familial ALS, their children have a 50 percent chance of developing the disease.
The inherited risk for MS is lower. There is only a 3 percent to 4 percent chance of developing MS if a first-degree relative (parent or sibling) has the disease, according to the Multiple Sclerosis Association of America.
While there is no definitive cause of ALS, scientists believe environmental factors may potentially play a role. Smoking for women (especially after menopause) appears to increase the risk, as does toxic chemical exposure.
Environmental risk factors for MS include vitamin D insufficiencies. Because vitamin D can be gained by exposure to sunlight, a higher incidence of this disease is found in northern geographic locations where there is less sunlight, farther from the equator.
Other potential causes of MS include smoking. “Women who smoke are 1.6 times more likely to develop MS than women who are nonsmokers,” according to the Multiple Sclerosis Association of America. Scientists also believe that some parasites might play a role in causing MS by changing the immune system and dampening its response.
Difficulty walking, weakness, muscle spasms, dropping things, tripping, and having trouble chewing, swallowing, and speaking can all be symptoms of both ALS and MS. Because there is symptom overlap, only thorough neurological testing by your doctor can diagnose either condition properly.
People with ALS lose the ability to control their muscles as nerve cells in the brain and spinal cord progressively degenerate. While not all people who have ALS report the same symptoms or rate of progression, the initial symptoms include garbled speech, tripping when walking, dropping objects, general tiredness, or a feeling of heaviness or weakness in the hands, arms, feet, or legs. ALS symptoms can also include involuntary laughing, crying, or yawning.
Typically, people with ALS do not report any cognitive symptoms, as the disease process limits itself to the anterior horn cells in the spinal cord and does not affect the brain. However, in very late stages of ALS, there may be some cognitive issues.
Early symptoms of MS also vary widely. Common MS symptoms include fatigue, dizziness, visual disturbances, and feelings of numbness or tingling. Unlike those with ALS, people with MS may also have symptoms that affect cognitive function.
Many of the symptoms of both MS and ALS mimic other conditions, so your doctor will need to begin the diagnostic process with a neurological exam. They will also ask you about your family medical history and your work history, and about potential environmental exposures you may have had.
If your neurologist suspects ALS, further diagnostic testing can include an MRI or CT scan of the brain and spine, an electromyography test for nerve conduction, and blood and urine tests to rule out other diseases and to test for the presence of metals. The doctor may also want a biopsy of nerve and muscle tissue and, occasionally, a lumbar puncture (also called a spinal tap). Because there is no definitive test for the disease, the ALS Association recommends getting a second opinion from a certified ALS specialist.
If your doctor suspects multiple sclerosis, they will also order a neurological exam. Diagnostic testing for MS may include an MRI, evoked potentials imaging, and a cerebrospinal fluid analysis. Blood tests will also be used to rule out other diseases like lupus and Sjogren's syndrome or possible infections and nutritional deficiencies.
ALS and MS are two distinctly different diseases, but there are rare cases when a dual diagnosis of both MS and ALS have been made.
While research continues to seek a cure for both diseases, neither MS nor ALS has a cure at this time. There has been some success in prolonging survival for people with ALS. Drug therapies can treat the symptoms of constipation, pain, depression, and involuntary displays of emotion that often accompany ALS. Physical and speech therapy, in combination with nutritional and breathing support, can minimize the pain of muscle contracture while maximizing mobility and the ability to communicate.
Treatments for MS fall into three categories: Disease-modifying therapies can slow disease progression. Treatment can address the symptoms of a flare-up. Other medications are available to manage MS symptoms to enhance function and quality of life.
ALS is always a continuously progressive disease, but people with some types of MS can have symptom-free periods between relapses.
According to the ALS Association, “The rate at which ALS progresses can be quite variable from one person to another. Although the mean survival time with ALS is three to five years, some people live five, 10, or more years.” Perhaps the most well-known case of long-term survial with ALS was theoretical physicist Stephen Hawking, who lived with ALS for more than 50 years.
As ALS progresses, the muscles used for walking, swallowing, chewing, talking, and breathing become affected. Feeding assistance and ventilators are required in the late stages of the disease, with the onset of paralysis. ALS is a fatal disease; every 90 minutes someone dies of ALS.
Currently, people who receive a diagnosis of MS usually have a life expectancy seven years less than the general population. Research reported by the University of Utah finds that death is usually not caused by MS directly, but by related complications from immobility, chronic infections, or compromised swallowing and breathing. However, with continued research, life expectancy is improving for people diagnosed with MS or ALS.
MyMSTeam provides a community of more than 139,000 people with MS. You can find emotional support, practical suggestions for enhancing your quality of life, and real-life feedback about therapies from people who are going through the same things you are.
Have you been through the diagnostic process for ALS or MS? What advice do you have for others going through diagnostic tests? Comment below or start a conversation on MyMSTeam.com. You never know who could benefit from your story.