What is MND?
Motor Neurone Disease (MND) also referred to as ALS (Amyotrophic Lateral Sclerosis) or Lou Gehrig’s disease, is a group of uncommon neurodegenerative diseases which affects the nerves (motor neurones) in the brain and spinal cord that causes rapidly progressive muscle weakness over time.
The motor nerves (motor neurones)—which are the “electrical wiring” in our body—sends signals from the brain and spinal cord to our muscles, telling the muscles what to do for movements. As MND progresses, it disables these biological functions for response and the nerves degenerate or “die-off” prematurely which causes rapid muscle weakness. There are four main types of MND.
Symptoms may include:
- muscle weakness and paralysis,
- impaired speaking,
- swallowing, and
Symptoms usually follow a pattern in three stages (depending on the progression in each person):
- Initial Stage,
- Advanced Stage, and
- End Stage.
Progression is generally rapid and is variable with an average life expectancy from three to five years (or occasionally longer) from the onset of symptoms. There is no direct cause of pain or discomfort from MND but there may be several indirect causes of muscle spasms and cramps, stiff joints, and other bedridden symptoms as people with MND often stay in bed. Learn more about the symptoms and effects of MND.
The impact on the MND community is usually measured by the Incidence and Prevalence of the disease.
- Incidence: The number of new cases added in a defined period, usually a year which is 2 per 100,000 of the total population
- Prevalence: The number of cases existing at any point in time, around 6 per 100,000 of the total population.
Research has found that the incidence is higher in people aged over 50 years. Only 10% of cases are familial (inherited), while the remaining 90% are sporadic (random and isolated instances without any identifiable causes).
Although classified as a “Rare Disease” based on its prevalence, MND is quite common with approximately 140,000 new cases diagnosed worldwide each year, that is 384 new cases daily.
With the global statistics and the population in Malaysia, it is estimated there are probably more than 2,000 Malaysians with MND and 600 newly diagnosed cases every year, which is around 50 Malaysians diagnosed with MND every month, whereby men are more susceptible compared to women.
Scientists around the world have yet to identify causes or cures for MND. However, they believe that significant treatment breakthroughs are possible.
What are the symptoms and effects of MND?
Symptoms vary for each person, and it is unlikely to develop all at once, or in any specific order. It depends on the pattern of the motor neurones involved and the part of the body where the symptoms begin.
As the disease progresses, symptoms are likely to affect different parts of the body. The effects of MND are from the impairment of the parts of the body affected by the disease that triggers other issues not caused directly by the disease.
Usually, sensations such as taste, smell, touch, and feeling hot or cold are not affected by the disease.
Common symptoms of MND include:
- Muscle weakness & wasting. Muscle weakness and deterioration of the upper limbs (arms) or lower limbs (legs) like muscle stiffness, cramps, and fasciculation (twitching). This results in tripping while walking, dropping or losing grip of objects.
- Slurring of speech and swallowing difficulties. Excessive salivation, slurring, and swallowing can occur due to weakness, wasting, and stiffness of the tongue and throat muscles.
- Breathing difficulties. A weakness of the respiratory muscles decreases lung capacity. A person may experience unrefreshing sleep, morning headaches, and excessive daytime tiredness.
- Fatigue. People often complain of tiredness caused by any of the following:
- muscle exhaustion & spasticity (muscle remains contracted/stiff/tight and resists being stretched, which affects movement),
- reduced stamina (due to a decrease in lung capacity),
- weight loss,
- metabolic changes,
- and reduced food intake.
Effects of MND include:
- Pain and discomfort. Motor neurones don’t transmit pain signals which means there is no direct cause of pain. However, muscle stiffness, spasms, and cramps can cause discomfort due to restricted mobility. This discomfort may be relieved by continually changing the sitting/sleeping posture, massaging the muscles and gentle exercise for stiff joints.
- Excessive saliva. As the throat muscles weaken, some people may struggle to swallow, causing saliva pooling or excessive saliva in the mouth and an increased risk of choking due to excess saliva.
- Bowel problems. There is no direct cause of the disease. However, constipation may occur due to restricted mobility, weak abdominal muscles, and altered diet and fluid intake. Diarrhoea can sometimes happen with a severely constipated bowel.
- Cognitive and behavioural changes. Up to 50% of people with MND may experience changes in cognition, language, behaviour, and personality, such as the difficulties with memory, learning, language and low concentration. Behavioural changes may include egocentric or selfish behaviour, apathy, irritation, loss of interest, recklessness, aggression and absence of insight into these changes. They may also find it challenging to recognise emotions in others and have altered sensitivity to social and emotional cues.
There are different types of MND?
There are four main types of MND, each depending on the pattern of the motor neurones involved and the part of the body where symptoms begin. There can be an overlap between the various types. The onset of symptoms varies for each individual and each affecting the person differently.
Motor Neurones are a type of nerve cell that sends messages around the body for motor functioning. There are two main kinds of motor neurones:
- Upper Motor Neurones (UMN): that are in the brain and runs through the spinal cord to send messages to the peripheral nerves.
- Lower Motor Neurones (LMN): that are in the peripheries after exiting the spinal cord and they transmit messages from the brain to the muscles.
The difference between the four main types of MND:
Amyotrophic Lateral Sclerosis
The most common form of MND. Affects 60% to 70% of people with MND.
Motor Neurones Affected
Affects both the UMN and LMN.
Symptoms depend on the part of the body where the muscles are first affected—the arm or the leg. Symptoms can include muscle wasting, weakness, stiffness, cramps and muscle fasciculation (twitching).
As the disease progresses, it affects the muscles controlling speech, swallowing and breathing. Some people may trip when they are walking, dropping things, or losing grip.
Average life expectancy is from two to five years from the onset of symptoms; however, with palliative care, some people live for ten years or more.
Progressive Bulbar Palsy
Affects about 20% of people with MND.
Motor Neurones Affected
Affects both the UMN and LMN.
Symptoms include muscle wasting, weakness, or stiffness of the tongue, slurring of speech, difficulty swallowing and problems with the thickness or amount of saliva.
Life expectancy is between six months and three years from the onset of symptoms.
Primary Muscular Atrophy
Affects only a small proportion of people, perhaps 10% of the people with MND.
Motor Neurones Affected
Affects mainly the LMN.
Sometimes MND can initially present as PMA, but as the disease progresses it starts to affect the UMN and the diagnosis then changes to ALS.
Symptoms include weakness or clumsiness of the hand.
Life expectancy is longer than that in ALS.
Primary Lateral Sclerosis
A rare form of MND. Affects 1% to 2% of people with MND.
Motor Neurones Affected
Affects mainly the UMN.
Sometimes MND can initially look like PLS, but as the disease progresses, the LMN is involved and the diagnosis then changes to ALS.
Symptoms include muscle weakness, stiffness in the lower limbs. However, some people may experience clumsiness in their hands or speech problems.
Pure PLS progresses slowly, and life expectancy could essentially be normal. However, it may be life-limiting, and disability levels can be high, depending on whether it remains as pure PLS or progresses into ALS.
Flail Arm / Flail Leg Variants
About 5% to 10% of people with MND display predominant LMN disorder affecting only the upper limbs (Flail Arm or Man-in-the-Barrel syndrome) or the lower limbs (Flail Leg). It is slowly progressive.
People can easily mistake Kennedy’s Disease for MND, as both diseases have similar traits & symptoms. Both conditions cause the weakening and wasting of muscle, affecting only the LMN. Kennedy’s Disease is a rare form of an inherited disease causing muscular atrophy leading to weakness. It is a slow, progressive disorder of the motor neurones which is caused by a genetic mutation that affects only adult males, but women may carry the mutation.
What causes MND?
The exact cause of MND is unclear. There are many theories, such as environmental toxins and chemicals, viral infections, genetic defects, and immune-mediated damage. MND strikes people of all ages; however, people with MND and their carers can manage the symptoms to help maintain the best possible quality of life.
Does MND start suddenly?
It is unlikely that MND starts suddenly. Even if a person notices the symptoms suddenly, the loss of motor neurones is likely to be well before the person is aware that they have MND. As the first affected motor neurones start to degenerate, the brain will learn to compensate for the loss so that there are no noticeable symptoms in the initial stage. However, the first symptoms only appear when the number of motor neurones damaged is so great that compensation is no longer possible.
What are the treatments for MND?
Currently, there is no cure for MND. However, there are up to four drugs approved by the U.S. Food & Drug Administration (USFDA) to slow down the progression of MND.
What is the available help or care for people with MND?
Although there is currently no cure for MND, you or your loved one can manage the symptoms with professional multidisciplinary care. Multidisciplinary care helps people with MND and their carers achieve the best possible quality of life through:
- Consultation with a Neurologist
- Neurorehabilitation with an Occupational Therapist (OT) or Physiotherapist
- Speech & Language Therapy with a Speech & Language Therapist (SLT)
- Dietary Recommendations with a Dietitian & Nutritionist
- Counselling with a Psychologist
- Palliative Care with a Palliative Specialist
Can family members help their loved ones that are diagnosed with MND?
Definitely! MND affects important muscle activities such as walking, gripping, swallowing, speaking and breathing. As the disease progresses, a person with MND will find some of these activities increasingly difficult and will be fully dependant on their family for support. Family support and teamwork are important to manage daily living and to maintain the best possible quality of life for a person with MND. It is important for the family to get involved and do their part; to plan and implement lifestyle changes that are suitable for a person with MND.