episodes of symptoms with extended period of
remission, treatment may consist of watchful
waiting and approaches to relieve symptoms that
become troublesome. People who have moderate
to severe episodes of symptoms with short periods
of remission may improve with medications
specifically for multiple sclerosis. Because these
medications have significant side effects, cannot
reverse neurologic damage that has already
occurred, or halt the progression of multiple scle-
rosis, doctors reserve their use for people whose
symptoms are debilitating. Other medications can
suppress the body’s immune response, helping
slow the attacks.
Lifestyle factors such as nutritious EATING HABITS
and daily physical activity help maintain motor
functions and coordination. WEIGHT LOSS AND
WEIGHT MANAGEMENTare essential for people who
have multiple sclerosis, as maintaining appropriate
body weight reduces the workload of the muscles.
Regular physical exercise also helps to counter
DEPRESSION. Most people are able to continue with
physical activities they enjoyed before developing
multiple sclerosis. Because heat exacerbates symp-
toms, people who live in warmer climates may
want to use the cooler early morning or late
evening hours for physical activities outdoors, and
use indoor air-conditioned facilities at other times.
Swimming provides good aerobic conditioning as
well as the opportunity to strengthen weakened
muscles in an environment of reduced resistance.
Though it is progressive, multiple sclerosis gen-
erally does not cause death or shorten life
expectancy. Most people who have multiple scle-
rosis are able to participate in the work and leisure
activities they enjoy when the condition is in
remission, and periods of remission may last 10
years or longer. People who have more aggressive
forms of multiple sclerosis may progress to assisted
mobility within a shorter period of time than peo-
ple who have the more classic, slowly progressive
forms of the condition.
Risk Factors and Preventive MeasuresMultiple sclerosis affects twice as many women as
men and most commonly makes its first appear-
ance between the ages of 20 and 40 years. It is
likely that external environment (such as climate)
and genetics both influence the development of
multiple sclerosis, as the condition is far less com-
mon in tropical regions of the world and more
likely to occur when other family members have
the condition. However, researchers do not fully
understand the connections among these factors.
Some researchers believe there may also be
involvement of an as yet undetected VIRUS. There
are no known measures for preventing multiple
sclerosis.
See also AMYOTROPHIC LATERAL SCLEROSIS (ALS);
AUTOIMMUNE DISORDERS; GENETIC PREDISPOSITION;
LESION; SCAR; SCOTOMA.myoclonus Involuntary and episodic contrac-
tions, twitching, or spasms of MUSCLE groups.
Harmless manifestations of myoclonus include
brief HICCUPS or the rapid jerking people may
experience when falling asleep (sometimes called
sleep starts). Myoclonus also may be a symptom of
injury to motor neurons, to the NERVEcells in the
SPINAL CORDthat direct voluntary movement, or
to parts of the BRAINthat participate in move-
ment. Myoclonus occurs as rapid, jolt-like
episodes and may take various forms that include
the following:- Action myoclonus occurs or intensifies during
attempts at voluntary movement, such as walk-
ing or eating. It most commonly develops after
circumstances of extended oxygen deprivation
to the brain (HYPOXIA), such as may occur with
STROKE, HEART ATTACK, or near drowning. - Essential myoclonus is not associated with any
detectable neurologic injury or dysfunction to
account for the symptoms. - Stimulus-sensitive myoclonus occurs as an
apparent HYPERSENSITIVITY REACTION(neurologic)
to external stimuli, such as sounds and lights. - Sleep myoclonus occurs when sleep starts
become excessive and disruptive to sleep. Some
neurologists believe sleep myoclonus is a form
of stimulus-sensitive myoclonus in which the
person may or may not recognize the external
stimuli that trigger the myoclonic episodes. - Cortical reflex myoclonus, reticular reflex
myoclonus, and progressive myoclonus
epilepsy, are SEIZURE DISORDERS that include
myoclonus among their symptoms.
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