Motor neurone disease (MND)

Motor neurone disease (MND) is a rare condition that progressively damages parts of the nervous system. This leads to muscle weakness, often with visible wasting.

Amyotrophic lateral sclerosis (ALS) is the most common form of MND.

MND happens when specialist nerve cells in the brain and spinal cord, called motor neurones, stop working properly and die prematurely. This is known as neurodegeneration.

Motor neurones control muscle activity like:

• gripping
• walking
• speaking
• swallowing
• breathing

As MND progresses, it can become more difficult to do some or all of these activities.

Symptoms of motor neurone disease

The symptoms of MND start gradually over weeks and months. They tend to appear on one side of the body first and get progressively worse.

There are usually 3 stages of symptoms.

Early symptoms

Sometimes the early symptoms are mistaken for similar conditions that also affect the nervous system.

Advanced symptoms

As MND becomes more advanced, more parts and functions of the body are affected. This can make you more likely to experience infections, like chest infections, which can cause your condition to get worse quicker.

End-stage symptoms

As MND progresses to its final phase, you might experience:

• increasing body paralysis, which means you'll need help with most daily activities
• significant shortness of breath

Eventually, non-invasive breathing assistance won't be enough to make up for the loss of normal lung function. At this stage, more medication can help to reduce symptoms of breathlessness and anxiety related to it. Most people with MND become increasingly drowsy before falling into a deep sleep, where they usually die peacefully.

Secondary symptoms

Some people with MND have other symptoms that aren't directly caused by the condition, but are related to the stress of living with it. These might include depression, insomnia and anxiety.

Causes of motor neurone disease

MND occurs when specialist nerve cells (motor neurones) in the brain and spinal cord progressively fail. It's not clear why this happens.

Genetic causes

One known cause of MND is an error in your genes with 20% of cases linked to genetic causes. Half of genetic cases will be in people who have a family history of MND. The other half of genetic cases will occur in those without a family history.

Having a family history of frontotemporal dementia can also increase the risk of inheriting MND.

The error in the gene affects the cells ability to perform normally and survive.

If you have a genetic form of MND, there's a chance that you could pass the risk of developing MND on to your child. The risk of them developing the condition can be affected by many factors like age.

Not everyone who has the genetic mutation will develop MND in their lifetime. Typically, the longer you live, the more likely you are to develop the condition.

If you have a parent with MND with no other family history of the disease, you're at a slight increased risk of MND of about 1.4%. The risk to the general population of MND is about 0.3%.

Other possible causes of motor neurone disease

It's unclear why the motor neurones begin to lose function. Most experts believe that it's a combination of factors that affect either the motor neurones or the cells that support them. There are some theories involving different cell processes including:

Diagnosing motor neurone disease

Speak to your GP if you experience the initial symptoms of MND.

After hearing about your symptoms and an initial exam, your GP might refer you to a neurologist (a doctor who specialises in conditions affecting the brain and nervous system).

Diagnosing MND can be difficult during the early stages. This is because many of the first symptoms can be caused by other more common health conditions like:

• a trapped nerve – wear and tear of the bones in the spine can sometimes cause nerves to become trapped under the spine
• peripheral neuropathy – where part of the nervous system is damaged by another condition, like type 2 diabetes
• swallowing difficulties caused by narrowing or inflammation of the gullet
• speech difficulties due to problems with the voice box
• damage to the brain by stroke or other neurological conditions like multiple sclerosis (MS) in younger people

Initial testing

MND is usually diagnosed by a neurologist based on the symptoms and a physical examination.

There's no single test for MND. Various tests might be used to rule out other possible causes of the your symptoms. Tests might include:

• blood tests – these can be used for several reasons, like checking that organs are working, or to look for a marker of muscle damage (creatinine kinase)
• magnetic resonance imaging (MRI) scan – to give a detailed picture of your brain and spinal cord
• electromyography (EMG) – measures the electrical activity in your muscles, which shows how well your motor neurones are working and connecting to the muscles
• nerve conduction test – similar to an EMG but measures how quickly your nerves can conduct an electrical signal
• lumbar puncture – a sample of spinal fluid might be tested to exclude an inflammatory or nerve condition caused by an infection
• muscle biopsy – in rare cases, a small sample of muscle might be removed for testing to determine whether the problem lies in the muscles

Gene tests can be used to support the diagnosis in some individuals. They might provide an explanation of why they've developed the disorder. Your GP can give you more information about specialists who can help with genetic testing.

Confirming the diagnosis

There are many reasons why there may be delays in diagnosis. The initial symptoms might not appear to be serious. Or symptoms might not be recognised as being related to the nervous system so a neurologist isn't consulted at first.

Sometimes, the diagnosis of MND is clear without the need for further tests. Confirming a diagnosis can sometimes be time-consuming even for an experienced neurologist. They might need a period of observation to be sure, particularly in cases where the condition progresses slowly. MND can only be diagnosed if the symptoms are clearly getting worse (progressive).

Receiving the diagnosis

Being told you have MND can be devastating and the news can be difficult to take in at first.

After you're diagnosed you should be provided with contact details of an MND care specialist. These are healthcare professionals with specialist experience caring for people with MND. They'll be able to give you (and your family) extra support after the diagnosis and during your time with the illness.

Talking to a counsellor or a trained clinical psychologist might help with feelings of depression and anxiety.

It's not unusual to have thoughts of taking your own life, although very few people with MND go on to do this. You should discuss these thoughts with your doctor.

Taking antidepressants or medicines to reduce anxiety may help. Your care team will be able to tell you about this.

Treating motor neurone disease

Although there's no cure for MND, there are treatments available to help relieve the symptoms.

A team of healthcare professionals will work together to help care for you. This multidisciplinary team typically includes:

• a neurologist and an MND care specialist
• a specialist in breathing (respiratory specialist)
• physiotherapists to advise on mobility aids
• occupational therapists to assess the need for adaptations to living environments
• speech and language therapist to provide help with communication and swallowing
• dieticians to support nutrition

As the conditions advances, you might also need palliative care.

Riluzole

Riluzole is the only licensed medication in the UK that's shown a survival benefit for people with MND. Riluzole is thought to slow down the damage to the motor neurone cells by reducing their sensitivity to the nerve transmitter glutamate.

In medical research, riluzole extended survival by 2 to 3 months on average.

Side effects of riluzole are usually mild and can include nausea, tiredness and, less commonly, a rapid heartbeat.

Very rarely, riluzole has been known to cause liver damage. If you're prescribed riluzole you'll need to have blood tests for the first few months to check your liver is working properly. If you've had significant liver disease, riluzole may not be suitable for you.

Treating symptoms

There are treatments available that can help relieve many of the symptoms of MND and improve your quality of life.

Research and drug trials

You might be given the opportunity to take part in research, including drug trials. Your MND care specialist and neurology consultant can provide further information on this.

Advice for carers

Caring for someone with MND can be both physically and emotionally demanding. It's likely you'll need a wide range of support.

For information and advice about all aspects of caring, visit Care Information Scotland