What is MND?

With motor neurone disease, known as MND, messages from the motor neurones gradually stop reaching the muscles. This leads the muscles to weaken, stiffen and waste, which can affect how you walk, talk, eat, drink and breathe. Some people also get changes to their thinking and behaviour, but the disease affects everyone differently. Not all symptoms will affect everyone, or in the same order. Symptoms also progress at varying speeds, which makes the course of the disease difficult to predict.

MND is life-shortening and there is no cure. Although the disease will progress, symptoms can be managed to help achieve the best possible quality of life.

We provide an overview about MND in our Introduction to motor neurone disease booklet, which is also available as an audio version. More detail can be found on our information for people with or affected by MND page.

You may come across medical and research terms when reading about MND - see our page on What do all the words and initials mean?

How many people are affected?

MND affects up to 5,000 adults in the UK at any one time. There is a 1 in 300 risk of getting MND across a lifetime. It can affect adults of any age, but is more likely to affect people over 50.

We provide further statistics if you would like more detail, but please be aware these contain sensitive content.

As motor neurone disease is not common, general health and social care professionals may not see many cases. This means it is important to seek out specialists who have appropriate experience in its treatment and care – usually with referral to neurological services. For more information, see our pages about health and social care services with MND.

With motor neurone disease (MND), you will experience a range of symptoms. These can be in a different order for each individual and progress at varying speeds.

The main forms of MND are described below. You may hear these called types of MND, but each form is just a way of describing how MND is likely to affect you.

As each form has overlapping symptoms, it can take time to be clear which one is affecting you. This is usually diagnosed by:

• seeing which area of the body is affected first
• monitoring the speed at which symptoms progress.

This means that as your symptoms are reviewed, your diagnosis might change from one form to another.

The information below includes details about life expectancy, so read when you feel ready to do so. Life expectancy can vary depending on which form of MND you have and how it affects you.

Amyotrophic lateral sclerosis (ALS):

This is the most common form of MND, with weakness and wasting in the limbs, muscle stiffness and cramps. It often begins with tripping over or dropping things. Life expectancy is usually two to five years from the onset of symptoms.

Bulbar onset MND or progressive bulbar palsy (PBP):

PBP affects a smaller number of people than ALS, and mainly affects the muscles of the face, throat and tongue. Early signs may include slurring of speech or difficulty swallowing. Life expectancy is between six months and three years from onset of symptoms.

Progressive muscular atrophy (PMA):

PMA affects only a small proportion of people. Early signs may show as weakness or clumsiness of the hands. Life expectancy is usually more than five years. See information sheet 2D – Progressive muscular atrophy.

Contact our MND Connect helpline for details about an email group for people with PMA or PLS (the MND Association is not responsible for the group or moderation of its content).

Primary lateral sclerosis (PLS):

PLS is a rare form of MND, causing mainly weakness and stiffness that usually begins in the lower limbs. You may also have speech problems or other symptoms. For detailed information about PLS, see our information sheet 2C – Primary lateral sclerosis. Usually, PLS is not life-shortening, as it progresses very slowly. This means it can take time to confirm a diagnosis of PLS.

Contact our MND Connect helpline for details about an email group for people with PMA or PLS (the MND Association is not responsible for the group or moderation of its content).

Kennedy’s disease (also known as spinal bulbar muscular atrophy or SBMA):

Kennedy's disease is a rare neurological condition with similar symptoms to MND, which means the two conditions are sometimes confused at diagnosis.  It affects motor neurones, causing increasing weakness, wasting of the muscles and hormonal changes. Most people with Kennedy’s disease live an average life span. See our Kennedy's disease pages and our Kennedy’s disease booklet.

Motor neurone disease (MND) affects everyone differently. Not everyone has all the symptoms or in the same order. The speed at which symptoms progress can also vary. Seek help from your health and social care professionals at the first sign of any change.

MND cannot be stopped or reversed, but therapies, equipment and medication can help manage symptoms. These can all help you achieve the best possible quality of life. We cover symptom control in our range of information resources including our guide, Living with motor neurone disease.

You may have some or all of the symptoms listed below:

• muscle weakness, with loss of muscle mass (wasting), and both movement and mobility problems
• muscle cramps and spasms, including rippling sensations, known as fasciculation
• stiff joints, which limit range of movement
• pain or discomfort, as a result of other symptoms (pain is not usually caused by MND directly)
• speech and communication problems, affecting how you speak, gesture and show expression
• swallowing difficulties, affecting how you eat and drink
• saliva problems, where thin saliva pools in the mouth or saliva becomes thick and sticky
• weakened coughing, which makes it harder to clear the throat
• breathing problems, which can lead to breathlessness and fatigue
• emotional lability, with inappropriate emotional responses, such as laughing when feeling sad
• changes to thinking and behaviour, for about half of those diagnosed with MND and this number increases in the later stages.

Changes to thinking and behaviour are usually mild, but a small number of people with MND may develop frontotemporal dementia, which is more severe and needs additional care support. See our booklet on Changes to thinking and behaviour with MND.

The senses are usually unaffected, so people can still see, hear, taste, smell and feel sensations. Some people may experience changes to taste, skin hypersensitivity or problems with temperature regulation.

Bladder and bowels are not usually affected by MND, but it may be harder to get to the toilet in time if mobility is affected. Constipation can also be a problem if you become less mobile or get dehydrated. Ask your GP for guidance.

Sexual function is not affected, but sexual expression may become more difficult if mobility and movement are restricted. See our booklet on Sex and relationships.

There are several forms of motor neurone disease (MND) and amyotrophic lateral sclerosis (ALS) is the most common form or type of the disease.

In the UK we use motor neurone disease (MND) as an umbrella term to cover all forms of the disease. In the USA, they use ALS as the umbrella term.

You can find out more on this page in the option Are there different types of MND?