Multiple
Sclerosis
Multiple
Sclerosis is one of the most common diseases of the central nervous system
(brain and spinal cord). MS is an inflammatory demyelinating condition. Myelin
is a fatty material that insulates nerves, acting much like the covering of an
electric wire and allowing the nerve to transmit its impulses rapidly. It is
the speed and efficiency with which these impulses are conducted that permits
smooth, rapid and coordinated movements to be performed with little conscious
effort. In Multiple Sclerosis, the loss of myelin (demyelination) is
accompanied by a disruption in the ability of the nerves to conduct electrical
impulses to and from the brain and this produces the various symptoms of MS.
The sites where myelin is lost (plaques or lesions) appear as hardened (scar)
areas: in Multiple Sclerosis these scars appear at different times and in
different areas of the brain and spinal cord - the term Multiple Sclerosis
meaning, literally, many scars.
What causes
MS?
The cause of
Multiple Sclerosis is not yet known, but thousands of researchers all over the
world are meticulously putting the pieces of this complicated puzzle together.
The damage to myelin in MS may be due to an abnormal response of the body's
immune system, which normally defends the body against invading organisms
(bacteria and viruses). Many of the characteristics of MS suggest an
'auto-immune' disease whereby the body attacks its own cells and tissues, which
in the case of MS is myelin. Researchers do not know what triggers the immune
system to attack myelin, but it is thought to be a combination of several
factors. One theory is that a virus, possibly lying dormant in the body, may
play a major role in the development of the disease and may disturb the immune
system or indirectly instigate the auto-immune process. A great deal of
research has taken place in trying to identify an MS virus. It is probable that
there is no one MS virus, but that a common virus, such as measles or herpes,
may act as a trigger for MS. This trigger activates white blood cells
(lymphocyles) in the blood stream, which enter the brain by making vulnerable
the brain's defence mechanisms ( i.e. the blood/brain barrier). Once inside the
brain these cells activate other elements of the immune system in such a way
that they attack and destroy myelin.
Who gets MS?
Women are more
likely to develop Multiple Sclerosis than men, MS occurring 50% more frequently
in women than in men (i.e. 3 women for every 2 men). Multiple Sclerosis is a
disease of young adults, the mean age of onset is 29-33 years, but the range of
onset is extremely broad from approximately 10-59 years. With the advent of
specialised diagnostic markers such as the Magnetic Resonance Imaging scanner
(MRI) there are cases of MS being definitely diagnosed in childhood rather than
in adolescence and the 15 years lower age limit, which is traditionally quoted
in many texts and handouts should not be taken as a fixed boundary for onset of
the disease. MS is not contagious, your friends and family cannot catch it from
you. MS is not an inherited disease, nor is it genetically transmitted, but
there does appear to be some genetic susceptibility to the disease, which
explains the fact that there is a slightly higher risk of Multiple Sclerosis in
families where it has already occurred. The slightly increased risk to children
and siblings of those with MS may reflect a common susceptibility and a similar
environment.
It is important
to establish who is most likely to develop MS and the geographic areas of
highest incidence. In the world map of MS prevalence, MS appears to be a
disease of temperate rather than tropical climates (i.e. there is more MS the
further one lives from the equator). In Northern Europe, particularly
Scandinavia and Scotland, there is a high incidence of MS, which may reflect a
specific susceptibility of the native population. Migration at particular ages
can affect susceptibility to developing MS. A child migrating from an equatorial
to temperate area (or temperate to equatorial) before puberty acquires the risk
of the area to which he/she has moved. The same relocation by an adolescent (or
older person) retains the risk characteristic of the area from which he/she
moved.
What are the
symptoms of MS?
Multiple
Sclerosis is a very variable condition and the symptoms depend on which area of
the central nervous system have been affected. There is no set pattern to MS
and everyone with MS has a different set of symptoms, which vary from time to
time and can change in severity and duration, even in the same person. The
systems commonly affected include:
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Visual disturbances
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Balance and co-ordination problems
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Weakness
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Spasticity
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Altered sensation
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Abnormal speech
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Fatigue
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Bladder and bowel problems
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Sexual intimacy
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Sensitivity to heat
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Cognitive emotional disturbances
There is no
typical MS. Most people with MS will experience more than one symptom, and
though there are symptoms common to many people, no person would have all of
them.
Visual
disturbances
á
blurring of vision
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double vision (diplopia)
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optic neuritis
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involuntary rapid eye movement
á
(rarely) total loss of sight
Balance and
co-ordination problems
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loss of balance
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tremor
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unstable walking (ataxia)
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giddiness (vertigo)
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clumsiness of a limb
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lack of co-ordination
Weakness
á
this can particularly affect the legs and walking
Spasticity
á
altered muscle tone can produce spasticity
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muscle stiffness can affect mobility and walking spasms
Altered
sensation
á
tingling
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numbness (paraesthesia)
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burning feeling in an area of the body
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other indefinable sensations
Pain may be
associated with MS, e.g. facial pain (such as trigeminal neuralgia) and muscle
pains
Abnormal
speech
á
slowing of speech
á
slurring of words
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changes in rhythm of speech
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difficulty in swallowing (dysphagia)
Fatigue
á
a debilitating kind of general fatigue (unpredictable or out of
proportion to the activity). Fatigue is one of the most common (and one of the
most troubling) symptoms of MS
Bladder and
bowel problems
á
bladder problems include the need to pass water frequently and/or
urgently
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incomplete emptying or emptying at inappropriate times
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bowel problems include constipation and, infrequently, loss of bowel
control
Sexual
intimacy
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impotence
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diminished arousal
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loss of sensation
Sensitivity to
heat
this symptom very
commonly causes a transient worsening of symptoms
Cognitive
emotional disturbances
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problems with short term memory
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concentration
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judgment
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reasoning
Whilst some of
these symptoms are immediately obvious, others such as fatigue, altered
sensation, memory and concentration problems are often hidden symptoms. These
can be difficult to describe to others and sometimes family and curers do not
appreciate the effects these have on the person with MS and on employment,
social activities and quality of life.
What are the
types of MS?
The course of MS
is unpredictable. Some people are minimally affected by the disease while
others have rapid progress to total disability, with most people fitting
between these two extremes. Although every individual will experience a
different combination of MS symptoms there are a number of distinct patterns
relating to the course of the disease:
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Relapsing-Remitting MS
In this form of
MS there are unpredictable relapses (exacerbations, attacks) during which new
symptoms appear or existing symptoms become more severe. This can last for
varying periods (days or months) and there is partial or total remission
(recovery). The disease may be inactive for months or years. Frequency - approx
25%.
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Benign MS
After one or two
attacks with complete recovery, this form of MS does not worsen with time and
there is no permanent disability. Benign MS can only be identified when there
is minimal disability 10-15 years after onset and initially would have been
categorised as relapsing-remitting MS. Benign MS tends to be associated with
less severe symptoms at onset (e.g. sensory). Frequency - approx 20%.
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Secondary Progressive MS
For some
individuals who initially have relapsing-remitting MS, there is the development
of progressive disability later in the course of the disease often with
superimposed relapses. Frequency - approx 40%.
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Primary Progressive MS
This form of MS
is characterised by a lack of distinct attacks, but with slow onset and
steadily worsening symptoms. There is an accumulation of deficits and
disability which may level off at some point or continue over months and years.
Frequency - approx 15% diagnosing MS.
Early MS may
present itself as a history of vague symptoms which may have subsided and many
of the signs could be attributed to a number of medical conditions. Therefore,
a period of time may elapse and a prolonged diagnostic process may be involved
before MS is suggested. On the other hand, a possible diagnosis of MS may be
more clear cut with classic symptoms (e.g. optic neuritis) and a distinct
chronology of attacks. The neurologist requires evidence that the types of
neurological deficits indicate involvement of at least two different areas of
the central nervous system with effects occurring at two separate times.
Multiple
Sclerosis is essentially a clinical diagnosis and there are no tests which are
specific for the condition and no single test is 100% conclusive. Therefore
several tests and procedures are needed to establish a diagnosis of MS and they
include the following investigations:
Medical
History
The physician
will ask for a medical history which will include your past record of signs and
symptoms as well as the current status of your health. The type of symptoms,
their onset and pattern may suggest MS, but a full physical examination and
medical tests will be needed to confirm the diagnosis.
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Neurological Examination
The neurologist
is testing for abnormalities in nerve pathways. Some of the more common
neurological signs involve changes in eye movements, limb co-ordination,
weakness, balance, sensation, speech, and reflexes. However, this examination
cannot conclude what is causing the abnormality and so other possible causes of
illness which produce similar symptoms to MS must be eliminated.
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Testing of Visual and Auditory Evoked Potentials
When
demyelination (scarring) occurs the conduction of messages along the nerves may
be slowed. Evoked potentials measure the time taken for the brain to receive
and interpret messages (nerve conduction velocity). This is done by placing
small electrodes on the head which monitor brain waves in response to visual
and auditory (hearing) stimuli. Normally, the brain's reaction to such stimuli
is almost instantaneous, but if there is demyelination in the central nervous
system a delay may occur. This test is not invasive or painful and therefore
does not require a stay in hospital.
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Magnetic Resonance Imaging (MRI)
The MRI scanner
is a more recent diagnostic test and takes very detailed pictures of the brain
and spinal cord, showing any existing areas of sclerosis (lesions or plaques).
Whilst this is the only test in which the lesions of Multiple Sclerosis can be
seen, it cannot be regarded as conclusive, particularly as not all lesions may
be picked up by the scanner and because many other conditions can produce
identical abnormalities. The MRI clearly shows the size, quantity and
distribution of lesions, and together with supporting evidence from medical
history and neurological examination, is very significant indicator toward
confirming the diagnosis of MS. The MRI is also a very useful tool in clinical
trials in assessing the value of new therapies by its ability to measure
disease activity in the brain and spinal cord
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Lumbar Puncture
In this test,
cerebrospinal fluid (the fluid which flows around the brain and spinal cord) is
tested for the presence of antibodies. Antibodies can occur with MS but they
can also occur with other neurological conditions. The fluid is taken from the
spinal cord by inserting a needle into the back and withdrawing a small amount
of fluid. A local anaesthetic is given to numb the skin, and therefore whilst
it is uncomfortable it is not usually painful. This test does require the
person to lay flat for a number of hours after the test, and may require an
overnight stay in hospital. Subsequently for some, a short period of
recuperation may be required. This test may indicate MS but is not in itself
conclusive.
The diagnosis of
MS is not always clear cut. The initial symptoms may be transitory and vague
and confusing to both the person and their doctor. Invisible or subjective
symptoms are often difficult to communicate to doctors and health professionals
and sometimes people are at first dismissed as being neurotic or a
hypochondriac.
Following an
episode for which you have sought medical advice, your doctor may not have told
you that MS is suspected. This delay may be very reasonable because the
neurologist may wish to witness at least two distinct episodes with symptoms
that are separated by at least a month and persisting for at least 24 hours.
A good relationship
with your neurologist and family physician is essential. MS may have times of
crisis and acute episodes which require specialist medical attention, but it is
a disease that must be lived and managed every day. The time of diagnosis is
stressful not only for the person with MS but for the family and carers who
should also be fully informed as to the diagnosis, prognosis, treatment,
management considerations and lifestyle adjustments associated with MS. The
family physician and the local MS Society are important ongoing resources for
care and information for those affected by MS.
The diagnosis of
MS is a shock and often stereotypes of wheelchairs and disability tend to
dominate one's thoughts. Nevertheless, it is most important to realise that
many people with MS and their carers have recognised that it is still possible
to live life to the full, taking into account any limitations caused by the
illness. Thus, it is often unnecessary to give up work, education and social
activities. Many people with MS can lead productive, fulfilling and relatively
normal lives.
What will
happen?
It is impossible
to predict accurately the course of MS for any individual, but the first five
years give some indication of how the disease will continue for that person.
This is based upon the course of the disease over that period and the disease
type. (i.e relapsing- remitting or progressive ). The level of disability
reached at end points such as five and ten years is thought to be a reliable
predictor of the future course of the disease. However, there are many
variables in this scenario: a large percentage of people with MS (approx 45%)
are not severely affected by MS and live normal and productive lives.
There is a
significant group (40%) which become progressive after a period of some years
as relapsing-remitting. Age at onset and gender may also be indicators of the
long-term course of the disease. Some research has indicated that younger age
at onset [under 16 years of age] implies a more favourable prognosis, but this
must be tempered by the knowledge that for a young adult living with MS for 20
or 30 years may result in substantial disability even if the progress towards
disability is slow and in the first 10 or 15 years he or she is relatively
mildly affected. Other research has indicated that late onset [ie over 55 years
of age], particularly in males, may indicate a progressive course of the
disease.
The prospect of
therapy for MS should be encouraging to those newly diagnosed with MS. Drugs
such as interferon beta are possible treatments for those who are
relapsing-remitting and ambulatory. The interferon betas may slow the
progression of disability as well as reduce the severity and frequency of
exacerbations. At this stage it is not known whether interferon beta has any
impact on primary progressive MS. The breadth of research currently targeting
MS gives hope that therapy which will interfere with the process of MS (even if
not curing the disease) is not an unreasonable expectation in the near future.
It should be
remembered that many people with MS go through life with a manageable
disability (e.g. fatigue, a limp, bladder problems). At least 15% of people
with MS, however, will become severely disabled (i.e.having to use a wheelchair
on a full-time basis). Life expectancy for persons with MS is near normal.
Fatigue in
Multiple Sclerosis
Fatigue is a
universal sensation experienced by most people. Generally, fatigue is an effect
which is proportional to the cause... for example the fatigue following exertion
or lack of sleep. In any nervous system disorder, the affected person often
notices that he or she tires more rapidly. In multiple sclerosis the fatigue
can be out of all proportion to the activities taking place.
Fatigue is one of
the most common MS complaints, being reported by over 75% of persons with MS.
It is one of the most difficult symptoms to treat and understand and because it
is invisible, its occurrence can cause misunderstanding, especially amongst
family, friends and employers. Family members may think that a person with MS
is not pulling their weight: sexual problems may arise between partners;
employers may label a person as being lazy. Fatigue can have a devastating
impact on daily activities, overall wellbeing and employment status. The cause
of MS fatigue is not fully understood. MS fatigue can be divided into four
categories:
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Normal fatigue - this occurs whether or not MS is present. Not all
fatigue is due to MS.
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Neuromuscular fatigue - this is caused by inefficient nerve conduction.
Respite periods are the solution to this Ôshort-circuiting' fatigue.
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Depression - depression in MS is common and is often accompanied by poor
sleep, poor appetite, depressed affect and fatigue.
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Lassitude - this is an overwhelming tiredness that comes on for no
obvious reason.
Because
neurochemical medications are helpful management tools, it is thought that
lassitude may be due to biochemical imbalances in the brain. As well as
disrupting daily life, MS fatigue can also cause anxiety when MS symptoms
reoccur during periods of fatigue. This is particularly so after exertion and
especially when activity or environment causes a rise in body temperature. It
should be noted that fatigue is not related to relapses and fatigue does not
cause worsening of the disease or a permanent increase in disability.
It is also
possible that the impact and experience of fatigue may be exacerbated by
psychosocial factors such as sense of control (i.e. the inability to
manipulate, control or change the environment to suit personal psychological
needs may be a factor in MS fatigue).
Management of
MS Fatigue
When fatigue
becomes a major problem for the person with MS, a thorough medical evaluation
should be undertaken to eliminate other causes of fatigue (eg infection). A
possible cause of MS fatigue may be sleep disturbances, which then result in
daytime fatigue.
If central
nervous system disease (in this case MS) is the sole basis for the fatigue,
then adjustments should be made to lifestyle, environment and occupation to
accommodate the fatigue. It may be necessary to change your role, or shift your
priorities within the family and at work, in order to pace yourself to avoid
fatigue. Techniques such as time management, pacing, energy conservation, work
simplification and relaxation breaks are all strategies which can be employed
to control fatigue.
Practical
tips:
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Avoid hot baths, very warm temperatures, excessive exercise, eating
large meals, smoking. Plan your life so work requirements, social occasions and
late nights are staggered. Follow a sensible diet, and reduce weight if
overweight. Yoga can be very helpful, combining exercise with meditation. Keep
physically fit, with a balanced programme of exercises that should be tailored
to your capabilities. You should not be exhausted by these exercises and they
should be followed by adequate rest periods.
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Few pharmacological agents have been effective in combating MS fatigue.
Amantadine (Symmetrel) has been shown to have some value in a percentage of
patients. Management of depression (and associated fatigue) should include
antidepressant medication and counselling.
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Stress management and counselling should not be ignored in the control
of fatigue. Psychosocial factors and quality of life concerns impact upon the
ability of people with MS to cope with their lives and may be a factor in the
cause of fatigue as well as a determinant of the degree to which it interferes
with daily living.
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In managing fatigue in MS it is also important to educate families and
friends and, as well, health care professionals and employers, as to the
existence of this aspect of MS. Fatigue is very much a symptom of MS but one
that can be managed if understood and accommodated.