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:
á Visual disturbances
á Balance and co-ordination problems
á Altered sensation
á Abnormal speech
á Bladder and bowel problems
á Sexual intimacy
á Sensitivity to heat
á 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.
á blurring of vision
á double vision (diplopia)
á optic neuritis
á involuntary rapid eye movement
á (rarely) total loss of sight
Balance and co-ordination problems
á loss of balance
á unstable walking (ataxia)
á giddiness (vertigo)
á clumsiness of a limb
á lack of co-ordination
á this can particularly affect the legs and walking
á altered muscle tone can produce spasticity
á muscle stiffness can affect mobility and walking spasms
á numbness (paraesthesia)
á burning feeling in an area of the body
á other indefinable sensations
Pain may be associated with MS, e.g. facial pain (such as trigeminal neuralgia) and muscle pains
á slowing of speech
á slurring of words
á changes in rhythm of speech
á difficulty in swallowing (dysphagia)
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
á incomplete emptying or emptying at inappropriate times
á bowel problems include constipation and, infrequently, loss of bowel control
á diminished arousal
á loss of sensation
Sensitivity to heat
this symptom very commonly causes a transient worsening of symptoms
Cognitive emotional disturbances
á problems with short term memory
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:
á 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%.
á 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%.
á 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%.
á 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:
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.
á 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.
á 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.
á 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
á 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:
á Normal fatigue - this occurs whether or not MS is present. Not all fatigue is due to MS.
á Neuromuscular fatigue - this is caused by inefficient nerve conduction. Respite periods are the solution to this Ôshort-circuiting' fatigue.
á Depression - depression in MS is common and is often accompanied by poor sleep, poor appetite, depressed affect and fatigue.
á 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.
á 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.
á 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.
á 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.
á 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.