All figures about MS are estimates. There are probably 70,000 to 100,000 people with MS in Britain. More women have it than men. Amongst children of people with MS about 1 in 200 may get it. Amongst the rest of the population the incidence of MS is about 1 in 700, though this varies in different parts of the country and the world. The majority of people with MS are diagnosed when they are aged between 20 and 40 though it can occur in older people and rarely in children. It is almost twice as common in women as in men.
Authorities say that most people with MS have a normal life expectancy. About 20% may eventually need to use a wheelchair. People with MS can have a good experience of life, including love, marriage, children, work and happiness.
Multiple sclerosis can cause a variety of symptoms. Initial attacks often come and go, and are relatively mild. They often do not prompt medical attention, and sometimes are only identified in retrospect, once the diagnosis has been made after further symptoms present.
The most commonly-associated symptoms of MS are as follows. (Note: this list is provided for information only, not as a means of self-diagnosis.)
- Cognitive impairment (e.g. recent memory, attention, processing speed, visual-spatial abilities and executive function)
- Depression/unstable mood
- Visual disturbances
- Eye twitches (nystagmus)
- Inflammation of the optic nerve (optic neuritis)
- Double-vision (diplopia)
- Speech & Throat
- Difficulty with speech/articulation (dysarthria)
- Swallowing weakness (dysphagia)
- Muscle weakness
- Muscle spasms or spasticity
- Lack of coordination (ataxia)
- Sensory changes or loss (hypoesthesia)
- Tickling, tingling, burning, pricking, or numbness of skin (paraesthesia)
- Bowel & Urinary
- Diarrhea or constipation
- Increased frequency in urination or lack of retention of urine
The symptoms of MS depend on which nerves are affected. Different nerves control different parts of the body and different sensations. Consequently, not everybody with MS will have exactly the same symptoms. People with MS may have any mixture of symptoms each to a varying extent, although extreme fatigue is the commonest one and nearly every sufferer will experience it at some time, with some it is a near permanent state.
Symptoms can appear to become more pronounced when the MS is active, and may lessen or disappear again when the MS is quiet. In some cases they may fluctuate during day to day social activities, e.g. tired, upset or anxious, heat/cold. These fluctuations do not necessarily mean that the MS is getting worse, only that the person with MS can have good days and bad days, just like everyone else.
TYPES OF MULTIPLE SCLEROSIS
MS is an individual condition. For some people, MS is characterised by periods of relapse and remission while for others it has a progressive pattern. For everyone, it makes life unpredictable. Most people diagnosed with MS will be described as having relapsing remitting MS, except for the small number of people who have primary progressive MS.
There are several types of MS:
1. Relapsing, remitting
In relapsing remitting MS, symptoms occur for a period of time-days, weeks, or months – and then improve either partially or completely.
Many people with MS call a relapse an ‘attack’ because this can describe the period of time they experience new problems or begin to feel unwell. A relapse is when new symptoms occur, or old symptoms re-occur, and last for more than 24 hours.
Relapses happen when inflammatory cells attack nerve fibres in the brain and spinal cord. If inflammation blocks messages in an area that has a specific function, such as the optic nerve, then symptoms occur. The myelin sheath can be damaged and sometimes, the nerve fibre (or axon) itself as damaged, too.
When the inflammation subsides, symptoms settle down (there may be some damage left behind which can improve over time) or entirely disappear. This is known as a remission. Remissions can last any length of time, even years. If, after ten to 15 years, your condition hasn’t worsened and you have minimal or no disability, you will be said to have benign MS. This doesn’t mean your MS will be free of problems – it means simply that you haven’t developed major disability, despite having MS for a long time. About 20 per cent of people with MS have benign MS.
2. Secondary Progressive
When someone with relapsing remitting MS shows a sustained deterioration for at least six months – whether or not they have relapsed as well – they are said to have secondary progressive MS. The progression probably results from the loss of nerve fibres (axons) during past relapses. Although myelin can repair itself (a process known as remyelination), axons cannot fully repair themselves.
It isn’t easy for doctors to tell when somebody moves from relapsing remitting to secondary progressive MS. Some people continue to have relapses in addition to progressive deterioration, while others don’t. Although nobody’s MS starts off being secondary progressive, it’s possible to be told you have this type at diagnosis of you’ve had unexplained symptoms for some time.
Not everybody with relapsing remitting MS goes on to develop the secondary progressive form. On average, by 15 years, approximately 65 per cent of people with relapsing remitting MS will have developed secondary progressive MS.
3. Primary Progressive
This is an unusual form of MS, affecting overall perhaps 10 to 15 per cent of people who has MS. People with primary progressive MS tend to be diagnosed when they are a little older, usually in their forties or later. Unlike relapsing remitting MS, men are just as likely to be diagnosed with primary progressive MS as women.
While the other types of MS can affect both the brain and spinal cord, in primary progressive MS the majority of lesions tend to be found in the spinal cord. People with primary progressive MS never have any distinct attacks or remissions but begin with subtle problems that slowly worsen over time – their MS is progressive from the beginning.
Problems tend to affect one main area and, for the majority of people, these are related to walking. However, people with primary progressive MS can experience any MS symptom.
MS is not directly inherited and, unlike some conditions, it isn’t caused by one faulty gene. However, there does appear to be a genetic component possibly a combination of genes – that makes some people more susceptible to developing MS.
This doesn’t mean that your relatives will develop MS too. Even if you have an identical twin, it doesn’t mean they will also get MS. (They are more likely not to get MS.) Different research studies have produced different figures and while it’s impossible to be precise, the overall chance of your children developing MS is small.