What Is Multiple Sclerosis?

Multiple Sclerosis (MS) is one of the most common neurological diseases among young adults and affects around 85,000 people in the UK with about 250,000 to 350,000 cases occurring annually in the USA. MS is the result of damage to a substance called myelin. Myelin is a protective sheath surrounding all the nerve fibres in the brain and spinal cord. It acts much like the covering of an electric wire, helping to conduct electrical impulses rapidly between the brain or spinal cord and the rest of the body. It is the speed and efficiency with which these impulses are conducted that permits smooth, rapid and co-ordinated movements to be performed with little conscious effort. When myelin is damaged, messages are slower, distorted, or non-existent and do not get through properly, thus producing the various symptoms of MS. The areas where myelin is lost or damaged appear as hardened areas (scars) known as plaques or lesions and in MS these scars appear at different times and in different areas of the brain and spinal cord. The term multiple sclerosis meaning literally, many scars.

Scientists know what forms MS can take and how it can develop, but they are still not sure why. They have plenty of clues about the causes, but still cannot quite piece them together. Treatments are available to help manage the symptoms, and new ones are being developed which have an impact on the course of the condition.

What Causes Multiple Sclerosis?

MS has many factors and probably more than one cause, which have still not been identified, but thousands of researchers all over the world are meticulously putting the pieces of this complicated puzzle together. The damage to myelin may be due to a viral or bacterial infection. One theory is that a virus disturbs the immune system, or indirectly sets off an auto-immune process; this means that the immune system attacks itself. As scientists have been unable to find one particular virus, which is responsible for MS, some researchers now think that a common virus may act as a delayed trigger.

Who Gets MS?

Women are 50% more likely to develop MS than men, ie. three women for every two men. MS is a disease of young adults, the average age of onset being 29-33 years, although people are usually diagnosed between the ages of 20 and 40, but it can be later. Children can also get MS but this is rare. MS is not contagious, it is not inherited nor is it genetically transmitted, although there is a slightly higher risk of MS in families where it has already occurred. MS is also more prevalent in temperate climates and the condition is more common in areas in northern latitudes such as Scotland.

What are the types of MS?

MS shows up differently in each person. Many people with MS are only mildly affected throughout their lives. At the other extreme a few people deteriorate rapidly from the beginning and can have a shortened life span. Most people with MS experience something in between these two scenarios. There are four main types of MS and a great deal or variability within each of them.


    This type starts with a small number of mild attacks followed by complete recovery. It does not worsen over time and there is no permanent disability. People can only be classified as having benign MS when they have little sign of disability 10-15 years after the original onset. Around 20% of people with MS have the benign form.


    Most people with MS start with this type which means they have attacks followed by remissions. During remissions they have fewer or no symptoms. During a relapse new symptoms may occur or previous ones return. A relapse may last hours, days, weeks or months and vary in severity, sometimes requiring hospitalisation. Around 25% of people with MS have the relapsing-remitting form.


    Many people who start out with relapsing-remitting MS develop a form known as secondary progressive. This means that disability does not go away after a relapse and progressively worsens between attacks, or that attacks disappear altogether, with a progression of disability. Around 40% of people with MS develop secondary progressive, usually about 15-20 years after the initial onset of MS.


    Some people with MS never have distinct relapses and remissions. From the start they experience steadily worsening symptoms and progressive disability. This may level off at any time, or may continue to get worse. Around 15% of people with MS have the primary progressive form of the disease which is also known as chronic progressive.

What are the symptoms of MS?

The course of MS is unpredictable. Some people are minimally affected by the disease while others have rapid progress to total disability. Every individual will experience a different combination of symptoms depending on which areas of the central nervous system have been affected. There is not a typical set of symptoms that applies to everyone and they can vary in severity and duration.

Symptoms may start with double or blurred vision, pain at the back of the eye or nerve pain in the face. Some people experience hearing problems, numbness, giddiness and loss of balance. Others find it hard to concentrate and may become forgetful, or experience anxiety, depression or other changes in behaviour. Other affected areas are those controlling sensation, strength, speech and swallowing, bladder control and sexuality. There may be nothing wrong with the actual muscles or sensory organs; it is simply that not all the right messages are getting through.

What’s being done through research?

Sufferers of MS are only too aware of the tremendous difficulties facing research workers in their search for the cause and treatment of this relatively common neurological disease. Basic research is intended to work towards an understanding of the nature of the disease while applied research is more concerned with management and treatment.

The Aims2Cure supported Research Technicians are investigating which growth factors stimulate production of myelin in the first place, in cultures of brain tissue and whether the same or different growth factors are responsible for repair after inducing myelin breakdown.

Hence, the continuation of our support is vital.