Amyotrophic Lateral Sclerosis (ALS) - Topic Overview

Topic Overview

What is amyotrophic lateral sclerosis?

Amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease, is a progressive wasting away of certain nerve cells of the brain and spinal column called motor neurons. The motor neurons control the voluntary muscles, which are the muscles that allow movement.

ALS is a progressive, disabling, fatal disease. The course of the disease is different for everyone and some people live with ALS for many years. Walking, speaking, eating, swallowing, breathing, and other basic functions become more difficult with time. These problems can lead to injury, illness, and other complications.

In the United States and most other parts of the world, 1 to 2 people per 100,000 develop ALS each year. Men are affected slightly more often than women. Although ALS may occur at any age, it is most common in middle-aged and older adults.^{1, 2}

What causes ALS?

The cause of ALS is unknown. About 5% to 10% of people with ALS have an inherited form of the disease.³ ALS is not contagious.

What are the symptoms?

Over a period of months or years, ALS causes increasing muscle weakness, inability to control movement, and problems with speaking, swallowing, and breathing. The first sign of ALS is usually slight weakness in one leg, one hand, the face, or the tongue. Other problems may include increasing clumsiness and difficulty performing tasks that require precise movements of the fingers and hands. Frequent muscle twitching may occur. The weakness slowly spreads to the arms and legs over a period of months or years. As the nerves continue to waste away and decrease in number, the muscle cells that would normally be stimulated by those nerves also start to waste away, and the muscles weaken.

It is important to remember that having muscle weakness, fatigue, stiffness, and twitching doesn't necessarily mean that you have ALS.

How is ALS diagnosed?

ALS may be difficult to diagnose, and the diagnosis may not become clear until symptoms have progressed or until additional testing and observation have taken place.

If your health professional thinks you have ALS, you will likely be referred to a neurologist for diagnosis and treatment. ALS is diagnosed through a careful medical history, a detailed physical exam of the nervous system (neurologic exam), and tests that evaluate nerve and muscle function.

Tests needed to confirm the diagnosis include electromyogram (EMG) and nerve conduction studies. EMG helps measure how well and how quickly the nerves and muscles are working. Nerve conduction studies test nerve function.

Other tests may be needed to rule out other possible causes of the symptoms. These tests may include a nerve or muscle biopsy (tissue sample), blood tests, or imaging tests, such as computed tomography (CT) or magnetic resonance imaging (MRI) scans.

How is it treated?

Although there is no cure for amyotrophic lateral sclerosis (ALS), treatment can help you maintain strength and independence, manage symptoms, and avoid complications for as long as possible. Treatment also focuses on providing emotional support as your disability increases.

Physical therapy and occupational therapy may help maintain strength and function and make the most of remaining abilities. Speech therapy can help maintain the ability to communicate as speaking problems develop. Various medicines may be used to relieve symptoms and make you more comfortable.

A medicine called riluzole (Rilutek) may prolong survival by about 2 months.⁴ It is not known exactly how the medicine works, but it may slow the release of certain brain chemicals (neurotransmitters) that are believed to play a role in ALS. Riluzole is the only medicine approved for the treatment of ALS.

What decisions might I face as ALS progresses?

If you (or someone in your family) have ALS, learn as much as you can about the disease and your options for care. What you value and want are important factors in making choices about your care. As ALS progresses, you may face decisions about how aggressively you want to treat complications, such as breathing problems, difficulty eating, or pneumonia. As you make these decisions, remember that what's right for one person with ALS may not feel right for another person.

As the muscles that control swallowing become weaker, some people have problems with food and saliva being inhaled into the windpipe. Taking medicine and getting enough food can also be a problem. If this happens, you may choose to have a tube surgically inserted through the skin into the stomach (percutaneous endoscopic gastrostomy, or PEG) as a way to get adequate nutrition and take medicines.

Help with breathing may be needed as the muscles of the chest become weaker. Initially, extra oxygen can be given through a nasal cannula, a flexible plastic tube that is placed in the nostrils. For mild breathing problems, machines that deliver air or extra oxygen through a face mask may be used. These machines are called bilevel positive airway pressure (BiPAP) or noninvasive positive pressure ventilation (NPPV) machines. For severe breathing problems, a surgical opening in the neck leading to the windpipe (tracheostomy) may be created so oxygen can be delivered through a tube in the tracheostomy. As ALS gets worse and breathing problems increase, some people choose to support their breathing by being on a breathing machine, or ventilator, all the time.

How aggressively to treat the problems from ALS is a personal decision that only you and your loved ones can make. Regardless of your choices, your comfort can be maintained. It is important to discuss treatment options and share your concerns with your doctor.

Frequently Asked Questions