Amyotrophic lateral sclerosis
Amyotrophic lateral sclerosis
Amyotrophic lateral sclerosis (a-mi-oh-TROH-fik LAT-ur-ul skluh-ROH-sis), or ALS, is a serious neurological disease that causes muscle weakness, disability and eventually death. ALS is often called Lou Gehrig's disease, after the famous baseball player who was diagnosed with it in 1939. In the U.S., ALS and motor neuron disease (MND) are sometimes used interchangeably.
Worldwide, ALS occurs in 1 to 3 people per 100,000. In the vast majority of cases — 90 to 95 percent — doctors don't yet know why ALS occurs. About 5 to 10 percent of ALS cases are inherited.
ALS often begins with muscle twitching and weakness in an arm or leg, or with slurring of speech. Eventually, ALS affects your ability to control the muscles needed to move, speak, eat and breathe.
Early signs and symptoms of ALS include:
The disease frequently begins in your hands, feet or limbs, and then spreads to other parts of your body. As the disease advances, your muscles become progressively weaker until they're paralyzed. It eventually affects chewing, swallowing, speaking and breathing.
In ALS, the nerve cells that control the movement of your muscles gradually die, so your muscles progressively weaken and begin to waste away. Up to 1 in 10 cases of ALS is inherited. But the remainder appear to occur randomly.
Researchers are studying several possible causes of ALS, including:
Established risk factors for ALS include:
It may be that ALS, similar to other diseases, is triggered by certain environmental factors in people who already carry a genetic predisposition to the disease. For example, some studies examining the entire human genome (genome-wide association studies) found numerous genetic variations that people with ALS held in common, and that might make a person more susceptible to ALS.
Environmental factors under study that may modify a person's individual risk of ALS include:
As the disease progresses, people with ALS experience one or more of the following complications:
The most common cause of death for people with ALS is respiratory failure, usually within three to five years after symptoms begin.
Preparing for your appointment
If you're having some of the early signs and symptoms of a neuromuscular disease such as ALS, you might first consult your family doctor, who will listen to your description of symptoms and do an initial physical examination. Then your doctor will probably refer you to a neurologist for further evaluation.
What you can do
Although a thorough workup usually means you're getting top-notch care, the process can be stressful and frustrating unless your medical team keeps you informed. These strategies may give you a greater sense of control.
What to expect from your doctor
Tests and diagnosis
Amyotrophic lateral sclerosis is difficult to diagnose early because it may appear similar to several other neurological diseases. Tests to rule out other conditions may include:
Treatments and drugs
Because there's no reversing the course of amyotrophic lateral sclerosis, treatments mainly involve efforts to slow the progression of symptoms and make you more comfortable and independent.
Your doctor may also prescribe medications to provide relief from:
Coping and support
Learning you have ALS can be devastating. The following tips may help you and your family cope:
Last Updated: 2010-12-02
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