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ALS (Lou Gehrig's Disease)

What Is ALS?

Amyotrophic lateral sclerosis (ALS) is a degenerative disease that affects the brain and spinal cord. ALS is a chronic disorder that causes a loss of control of voluntary muscles. The nerves controlling speech, swallowing, and limb movements are often affected. Unfortunately, a cure has not yet been found for it.

The famous baseball player Lou Gehrig was diagnosed with the disease in 1939. ALS is also known as Lou Gehrig’s disease.

What Are the Causes of ALS?

ALS can be classified as either sporadic or familial. Most cases are sporadic. That means no specific cause is known.

The Mayo Clinic estimates that genetics only cause ALS in about 5 to 10 percent of cases. Other causes of ALS aren’t well understood. Some factors that scientists think might contribute to ALS include:

  • free radical damage
  • an immune response that targets motor neurons
  • imbalances in the chemical messenger glutamate
  • a buildup of abnormal proteins inside nerve cells

The Mayo Clinic has also identified smoking, lead exposure, and military service as possible risk factors for this condition.

The onset of symptoms in ALS usually occurs between the ages of 50 and 60, although symptoms can occur earlier. ALS is slightly more common in men than in women.

How Often Does ALS Occur?

According to the ALS Association, every year about 6,400 people in the United States are diagnosed with ALS. They also estimate that around 20,000 Americans are currently living with the disorder. ALS affects people in all racial, social, and economic groups.

This condition is also becoming more common. This may be because the population is aging. It could also be due to increasing levels of an environmental risk factor that hasn’t been identified yet.

What Are the Symptoms of ALS?

Both sporadic and familial ALS are associated with a progressive loss of motor neurons. The symptoms of ALS depend on what areas of the nervous system are affected. These will vary from person-to-person.

The medulla is the lower half of the brainstem. It controls many of the body’s autonomic functions. These include breathing, blood pressure, and heart rate. Damage to the medulla can cause:

  • slurred speech
  • hoarseness
  • difficulty swallowing
  • emotional lability, which is characterized by excessive emotional reactions such as laughing or crying
  • a loss of tongue muscle contour, or tongue atrophy
  • excess saliva
  • difficulty breathing

The corticospinal tract is a part of the brain made up of nerve fibers. It sends signals from your brain to your spinal cord. ALS damages the corticospinal tract and causes spastic limb weakness.

The anterior horn is the front part of the spinal cord. Degeneration here can cause:

  • limp muscles, or flaccid weakness
  • muscle wasting
  • twitching
  • breathing problems caused by weakness in the diaphragm and other respiratory muscles

Early signs of ALS may include problems performing everyday tasks. For example, you may have difficulty climbing stairs or getting up from a chair. You might also have difficulty speaking or swallowing, or weakness in your arms and hands. Early symptoms are usually found in specific parts of the body. They also tend to be asymmetrical, which means they only happen on one side.

As the disease progresses, the symptoms generally spread to both sides of the body. Bilateral muscle weakness becomes common. This can lead to weight loss from muscle wasting. The senses, the urinary tract, and bowel function usually remain intact.

Does ALS Affect Thinking?

Cognitive impairment is a common symptom of ALS. Behavioral changes can also occur without mental decline. Emotional lability can occur in all ALS sufferers, even those without dementia.

Inattention and slowed thinking are the most common cognitive symptoms of ALS. ALS-related dementia can also occur if there’s cell degeneration in the frontal lobe. ALS-related dementia is most likely to occur when there’s a family history of dementia.

How Is ALS Diagnosed?

ALS is usually diagnosed by a neurologist. There’s no specific test for ALS. The process of establishing a diagnosis can take anywhere from weeks to months.

Your doctor may start to suspect you have ALS if you have progressive neuromuscular decline. They’ll watch for increasing problems with symptoms such as:

  • muscle weakness
  • wasting
  • twitching
  • cramps
  • contractures

These symptoms can also be caused by a number of conditions. Therefore, a diagnosis requires your doctor to rule out other health problems. This is done with a series of diagnostic tests including:

  • an EMG to evaluate the electrical activity of your muscles
  • nerve conduction studies to test your nerve function
  • an MRI that shows which parts of your nervous system are affected
  • blood tests to evaluate your general health and nutrition

Genetic tests may also be useful for people with a family history of ALS.

How Is ALS Treated?

As ALS progresses, it becomes more difficult to breathe and digest food. The skin and subcutaneous tissues are also affected. Many parts of the body deteriorate, and all of them must be treated appropriately.

Because of this, a team of doctors and specialists often work together to treat people with ALS. Specialists involved in the ALS team might include:

  • a neurologist who is skilled in the management of ALS
  • a physiatrist
  • a nutritionist
  • a gastroenterologist
  • an occupational therapist
  • a respiratory therapist
  • a speech therapist
  • a social worker
  • a mental health professional
  • a pastoral care provider

Family members should talk to people with ALS about their care. People with ALS may need support when making medical decisions.


Riluzole (Rilutek) is currently the only drug approved for the treatment of ALS. It can prolong life by several months, but it cannot eliminate the symptoms entirely. Other medications may be used to treat the symptoms of ALS. Some of these medications include:

  • quinine bisulphate, baclofen, and diazepam for cramping and spasticity
  • nonsteroidal anti-inflammatory drugs (NSAIDs), the anticonvulsant gabapentin, tricyclic antidepressants, and morphine for pain management
  • Neurodex, which is a combination of vitamins B-1, B-6, and B-12, for emotional lability

Scientists are investigating the use of the following for a subtype of hereditary ALS:

  • coenzyme Q10
  • COX-2 inhibitors
  • creatine
  • minocycline

However, they have not yet been proven effective.

Stem cell therapy also hasn’t been proven to be an effective treatment for ALS.

What Are the Complications of ALS?

The complications of ALS include:

  • choking
  • pneumonia
  • malnutrition
  • bed sores

What Is the Long-Term Outlook for People with ALS?

The typical life expectancy for a person with ALS is two to five years. Approximately 20 percent of patients live with ALS for over five years. Ten percent of patients live with the disease for over 10 years.

The most common cause of death from ALS is respiratory failure. There’s currently no cure for ALS. However, medication and supportive care can improve your quality of life. Proper care can help you live happily and comfortably for as long as possible.

Content licensed from:

Written by: Verneda Lights and Elizabeth Boskey, PhD
Medically reviewed on: Jan 27, 2016: Rebekah Harding (UIC)

This feature is for informational purposes only and should not be used to replace the care and information received from your health care provider. Please consult a health care professional with any health concerns you may have.
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