Amyotrophic lateral sclerosis (ALS), often referred to as “Lou Gehrig’s disease,” is a progressive neurodegenerative disease that attacks nerve cells in the brain and the spinal cord. Motor neurons reach from the brain to the spinal cord and from the spinal cord to muscles throughout the body. The progressive degeneration of motor neurons in ALS ultimately lead to their death. When motor neurons die, the ability of the brain to initiate and control muscle movement is lost. With voluntary muscle action progressively affected, patients have difficulty talking, walking, eating, and eventually, breathing. Patients in the later stages of the disease become totally paralyzed. Yet, through it all, for the vast majority of people, their minds remain unaffected.
Kimberly has also written an ALS explanation for children.
A-myo-trophic comes from the Greek language. “A” means no or negative. “Myo” refers to muscle, and “Trophic” means nourishment—”No muscle nourishment.” When a muscle has no nourishment, it atrophies, or wastes away. “Lateral” identifies the areas in a person’s spinal cord where portions of the nerve cells that nourish the muscles are located. As this area degenerates it leads to scarring or hardening (”sclerosis”) in the region. As motor neurons degenerate, they can no longer send impulses to the muscle fibers that normally result in muscle movement. Early symptoms of ALS often include increasing muscle weakness, especially involving the arms and legs, speech, swallowing and breathing. When muscles no longer receive messages from the motor neurons they require to function, the muscles begin to atrophy causing limbs to look thinner.
The body has many kinds of nerves. There are those involved in the process of thinking, memory, and of detecting sensations, and others for vision, hearing, and other bodily functions. The nerves that die when you have ALS are the motor neurons that provide voluntary movements and muscle power. Examples of voluntary movements are your making the effort to reach for the phone or step off a curb; these actions are controlled by the muscles in the arms and legs. The heart and the digestive system are also made of muscle but a different kind, and their movements are not under voluntary control. When your heart beats or a meal is digested, it all happens automatically. Therefore, the heart and digestive system are not involved in ALS. Breathing may also seem involuntary. Remember, though, while you cannot stop your heart, you can hold your breath – so ALS will eventually have an impact on breathing.
Based on U.S. population studies, a little over 5,600 people in the U.S. are diagnosed with ALS each year. It is estimated that as many as 30,000 Americans have the disease at any given time. This challenging disease knows no racial, ethnic or socioeconomic boundaries. It can strike anyone at any time. Most people who develop ALS are between the ages of 40 and 70, although ALS can afflict any adult at any time in their lives. The typical life expectancy is between two and five years for the majority of ALS patients, but many people live much longer than this time frame. Generally, more patients are living longer with this disease than they have in the past.