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About ALS
What is ALS?
What does "Amyotrophic Lateral Sclerosis" mean?
Are there other Names for ALS?
Who gets ALS?
How common is ALS?
What are the symptoms?
How is ALS diagnosed?
What is the treatment?
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Books and Videos - coming soon
What is amyotrophic lateral sclerosis (ALS)?
Amyotrophic lateral sclerosis (ALS), also known
as Lou Gehrig's disease, is a neuromuscular disorder that
causes progressive paralysis and ends in death. ALS is
a motor neuron disease, first described in 1869 by the
noted French neurologist Jean-Martin Charcot. Although
the cause of ALS is not completely understood, ALS causes
a degeneration of the motor neurons in the brain and spinal
cord. When these cells die, it is impossible for the brain
to signal voluntary muscle control. People with ALS may
experience muscle weakness and impaired speaking, swallowing
and breathing; and eventually total paralysis and death.
ALS is a progressive, degenerative disease of the nervous
system. It is one of a group of diseases, called motor
neuron diseases (MND), in which specialized nerve cells
that control movement of the voluntary muscles gradually
cease functioning and die. These nerve cells, called motor
neurons, carry impulses from the brain to the brainstem
and the spinal cord. The impulses are then carried to
the muscles. The muscles respond to these messages by
coordinated relaxation or contraction corresponding to
willed movement. In ALS and other motor neuron diseases,
motor neurons gradually deteriorate. Because the nerve
cells that stimulate them have died, the muscle tissues
waste away. This results in progressive muscle weakness,
atrophy, and often spasticity, or excess muscle tone.
Only the motor neurons are affected. Other nerve cells,
such as sensory neurons that bring information from sense
organs to the brain, remain healthy.
ALS attacks only 'motor' neurons. Sight, touch, hearing,
taste, smell and muscles of the eyes and bladder are generally
not affected. Sexual function and drive are not affected.
The mind is not affected, and remains sharp despite the
progressive degenerating condition of the body.
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What does "Amyotrophic Lateral Sclerosis"
mean?
"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.
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Are there other names for ALS?
ALS, also known as motor neuron disease (MND),
is commonly called Lou Gehrig's disease for the famous
New York Yankee's baseball player who died of ALS in 1941.
ALS is sometimes referred to as Charcot's disease for
the French neurologist Jean-Martin Charcot who identified
the disease in 1869.
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Who gets ALS?
Most who develop ALS are between 40 and 70 years
of age, although the disease can strike at any age. Men
are affected slightly more frequently than women. ALS
occurs throughout the world regardless of racial, ethnic
or socioeconomic status.
Some studies have identified areas that at certain times
have appeared to have greater than expected numbers of
cases. This has occurred in the past in the western Pacific
islands and in parts of Japan and Australia. Other areas
in the continental United States have been reported but
have not stood up to careful epidemiological investigations.
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How common is ALS?
More than 5,600 Americans are diagnosed with
ALS each year or two new ALS cases per 100,000 people
(incidence). Approximately 35,000 people at any given
time are living with ALS in the United States or six to
eight people per 100,000 population (prevalence). The
incidence of ALS is close to that of multiple sclerosis
and four times that of muscular dystrophy.
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What are the symptoms of ALS?
ALS strikes people in different ways and progression
of the disease is often irregular. The groups of muscles
affected and the order in which they are affected varies
from one person to another. Early symptoms usually include
tripping, dropping things, abnormal fatigue of the arms
and/or legs, changes in speaking or slurred speech, difficulty
swallowing, muscle cramps , spasms, and twitches and uncontrollable
periods of laughing or crying. The hands and feet may
be affected first, causing weakness or difficulty in coordination
in one limb, difficulty in walking or using the hands
for the activities of daily living such as dressing, washing
and buttoning clothes.
About 25% of patients have bulbar (throat) onset, which
means that voice and swallowing are first affected. About
50% have arm onset, and 25% leg onset.
The disease frequently takes its toll before being positively
diagnosed: many patients are significantly debilitated
before learning that they have ALS.
Muscle wasting gradually spreads to the muscles of the
trunk of the body, and the disease eventually affects
swallowing, chewing and breathing. Complete paralysis
eventually results, usually occurring within two to five
years of diagnosis.
When the diaphragm is attacked, the patient is unable
to breathe for him/herself, and faces permanent ventilator
support in order to survive.
ALS attacks only 'motor' neurons. Sight, touch, hearing,
taste, smell and muscles of the eyes and bladder are generally
not affected. Sexual function and drive are not affected.
The mind is not affected, and remains sharp despite the
progressive degenerating condition of the body.
The symptoms and clinical features of the disease depend
on the location of the affected motor neurons. Speech
and swallowing impairments are called bulbar symptoms.
They indicate that neurons in the brainstem are affected.
Weakness of the respiratory muscles, muscle weakness,
and loss of mobility in the arms and legs are called somatic
symptoms. They indicate spinal cord involvement. In classical
ALS, a mixture of upper and lower motor neurons are involved,
with both bulbar and somatic symptoms.
• Lower motor neuron symptoms
Weakness and muscle wasting are common when
lower motor neuron involvement predominates. The patient
or physician usually notices fasciculation, or muscle
twitching. Fasciculation is a sign of muscle irritability,
as the normal action of the lower motor neuron on the
muscle is impaired. The sole involvement of lower motor
neurons can be seen in a form of ALS called progressive
muscular atrophy. Fasciculation is described as "benign"
if there is no muscle weakness, atrophy, or impairment
of motor function. Fasciculation is described as "pathologic"
when it occurs in ALS with other symptoms.
• Upper motor neuron symptoms
Spasticity, or stiffness, in the lower limbs,
face, or jaw indicates upper motor neuron involvement.
Spasticity in the legs often produces severe walking difficulties.
The patient may complain of heaviness, fatigue, stiffness,
or lack of coordination of any affected limb. Reflexes
are very brisk, or exaggerated. Outbursts of laughter
or crying with minimal provocation can occur. This is
called emotional lability and is referred to as a pseudo-bulbar
affect. Both brisk reflexes and emotional lability involve
the inability to inhibit reflexes.
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How is ALS diagnosed?
The diagnosis of ALS is a "clinical diagnosis,"
meaning there is no specific test that gives a definitive
answer. Before a diagnosis of ALS is confirmed, many tests
must be administered to rule out illnesses with symptoms
that may mimic ALS. These may include an MRI of the brain
or spinal cord, an electromyography (EMG) study of nerve
and muscle function and a variety of blood and urine tests.
By evaluating these tests, the patient's medical history
and performing a complete neurological exam, the neurologist
can usually reach a definitive diagnosis.
It is always recommended that patients seek a second opinion
by a neurologist experienced with ALS in order to decrease
the possibility of an incorrect diagnosis. In some cases
a definitive diagnosis can be made only after several
months of observation and retesting.
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Is there any treatment for ALS?
Many of the symptoms of ALS are treatable, but
there are no drugs available to cure the disease. Rilutek©,
the first FDA-approved medication for the treatment of
ALS, has been shown to modestly increase lifespan. Since
it became available in 1996, two retrospective studies
presented at the 12th International Symposium on ALS/MND
in 2001 indicated that Rilutek© appears to have a
greater impact on life expectancy than was reported in
initial drug trials.
The quality of life of patients with ALS can often be
improved by various treatments and interventions. Proper
positioning, exercise, physiotherapy, and medications
can help keep patients comfortable. Patients with significant
bulbar involvement may require help to improve communication
or ensure safe and adequate nutrition. A gastrostomy (feeding)
tube may be suggested if there is recurrent pneumonia,
high risk of aspiration (inhaling food or liquids into
the lungs), inadequate nutrition, rapid weight loss, or
extended feeding time. A wide range of devices and techniques
can address problems with communication. Ultimately, ALS
may result in respiratory decline, requiring consideration
of respiratory support, including non-invasive ventilation
such as a BiPAP (bilevel positive airway pressure), or
a tracheostomy and a ventilator.
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