Amyotrophic Lateral Sclerosis
Amyotrophic lateral sclerosis(ALS), sometimes called Lou Gehrig's Disease, is a progressive neurological disease that attacks the nerve cells (neurons) that control voluntary muscles. This disease belongs to a group of motor neuron disorders (e.g., muscular dystrophy, multiple sclerosis, Parkinson's disease) that are characterized by the gradual degeneration and death of motor neurons.
What Are Motor Neurons?
Motor neurons are nerve cells located in the brain, brainstem, and spinal cord. These motor neurons serve as connections from the nervous system to the muscles in the body. Imagine wanting to brush your teeth. This intention is transmitted by the motor neurons in the brain (upper motor neurons) to the motor neurons in the spinal cord (lower motor neurons). The lower motor neurons then relay the message to the muscle, or group of muscles, needed to complete the action.Effects of ALS
ALS causes both the upper and lower motor neurons to degenerate or die. Both the brain and spinal cord lose the ability to initiate and send messages to the muscles in the body. The muscles, which are unable to function, gradually atrophy (waste away) and twitch (fasciculate). The start of ALS can be very subtle with initial symptoms being weakness in affected muscles. Where this weakness first appears differs for different people. Regardless of what part of the body experiences the first effects of ALS, muscle weakness and atrophy spread to other parts of the body as the disease progresses. Arms and legs tire easily.
In some cases, initial symptoms affect only one leg or arm. Patients may have awkwardness and stumbling when walking or running. They may have difficulty lifting objects or with tasks that require manual dexterity (e.g., buttoning a shirt, tying a shoe, turning a key). Eventually the individual will not be able to stand or walk, get in and out of bed without help, or use hands and arms to perform activities of daily living, such as washing and dressing.
Eventually, when the muscles in the diaphragm and chest wall become too weak, patients require a ventilator to breathe. Most people with ALS die from respiratory failure, usually 3 to 5 years after being diagnosed; however, some people survive 10 or more years after diagnosis.
ALS does not impair a person's mind, as the disease affects only the motor neurons. Personality, intelligence, memory, and self-awareness are not affected. The senses of sight, smell, touch, hearing, and taste remain intact as well.Speech and Swallowing
ALS first affects an individual's ability to speak loudly and clearly, and eventually, completely prevents speaking and vocalizing. Some of the earliest speech-related symptoms of ALS may include nasal speech quality; difficulty pronouncing words due to weak, tight, or stiff speech muscles (dysarthria); and difficulty with lengthy sentences or conversation . As muscles for breathing weaken, it becomes more difficult for patients to speak loud enough to be understood. Eventually extensive muscle atrophy eliminates one's ability to vocalize and speak altogether.
Patients may also experience difficulty chewing and swallowing. Initially only some food consistencies are affected, but over time it becomes difficult for the patient to swallow even pureed foods and saliva. Fatigue decreases one's endurance for eating entire meals. All of these factors contribute to difficulty maintaining adequate nutrition and weight. Eventually doctors
may decide that it is best to insert a feeding tube into the patient's stomach to ensure proper nourishment and reduce the risk of choking and pneumonia that can result from inhaling liquid or food into the lungs.Who Gets ALS?
Amyotrophic lateral sclerosis affects as many as 20,000 Americans at any given time, with 5,000 new cases being diagnosed in the United States each year. ALS affects people of all races and ethnic backgrounds. Men are about 1.5 times more likely than women to be diagnosed with the disease.
ALS strikes in the prime of life, with people most commonly diagnosed between the ages of 40 and 70. However, it is possible for individuals to be diagnosed at younger and older ages. About 90-95% of ALS cases occur at random, meaning that individuals do not have a family history of the disease and other family members are not at increased risk for contracting the disease. In about 5-10% of ALS cases there is a family history of the disease.Role of the Speech-Language Pathologist
As it becomes more difficult to understand the speech of a person with ALS, therapy focuses on teaching strategies and techniques to maintain functional speech such as slowing down speech or using a communication aid to supplement speech. The eventual focus of therapy is on selecting and using augmentative and alternative communication (AAC) aids
(e.g., speech synthesizers, computer-based communication systems, responding to yes-no questions with eye movements) and other non-verbal techniques to express one's ideas and needs. Therapy never focuses on strengthening muscles, as exercise to fatigue can actually hasten neurological deterioration. Additionally, speech drills can be so tiring that the person is too fatigued to use speech muscles for communication purposes.
Speech therapy is a vital component of treatment for the ALS patient at all stages of the disease, as the inability to communicate with family, friends, nurses/doctors/therapists, and colleagues can lead to a sense of helplessness and eventual depression
. In the beginning stages of the disease, the learning of compensatory strategies for slurred speech can make day-to-day communication less frustrating for both the patient and communication partners. As the disease progresses, learning to use augmentative and alternative communication aids allows the individual to express basic needs and ideas, as well as participate in conversation, write, and even continue work.
Speech-language pathologists teach caregivers how to compensate for muscle fatigue when eating (e.g., eating many small meals during the day rather than three large meals) and when to change the texture of food and liquids to. They work together with doctors and dietitians to make sure the person is maintaining adequate nutrition and weight.
Find a speech-language pathologist near you.Links
The following web sites can provide information and support for people with ALS and their families:
Amyotrophic Lateral Sclerosis Association of America www.alsa.org
Center for Neurologic Study www.cnsonline.org
Les Turner ALS Foundation www.lesturnerals.org
The Muscular Dystrophy Association www.mdausa.org
Project ALS www.project-als.org
National Institute of Neurological Disorders and Stroke
Neuromuscular Disease Center at Washington University School
of Medicine St. Louis www.neuro.wustl.edu/neuromuscular/motor.html
National Organization for Rare Disorders www.stepstn.com/nord/rdb_sum/57.htm
Chapter of the ALS AssociationÂ http://www.alswp.org/Â
Drug Infonet www.druginfonet.com/lougerig.htm
Doctor's guide and information about ALS www.pslgroup.com/ALS.HTM
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