Basic facts about MND
Motor neurone disease (MND) is the name given to a group of closely related disorders that affect the motor neurones. Motor neurones are nerve cells that control the voluntary movement of muscles.
ALS (amyotrophic lateral sclerosis) is the most common sub-type of MND. MND is known as ALS in some countries.
Upper motor neurones run from the brain to the brainstem or spinal cord to connect with lower motor neurones. Lower motor neurones then travel out to connect with the muscles for swallowing, chewing, tongue movement, facial expression, breathing, coughing, and limb movement.
Degeneration of the motor neurones result in progressive muscle wasting and weakness because the nerve supply to the muscles is impaired. This causes progressive loss of mobility in the limbs, and difficulties with speech, swallowing, and breathing. The progression varies significantly from person to person.
What causes MND?
In most cases, MND occurs in an individual with no known family history. There are many theories about the potential causes of MND. These include:
- exposure to environmental toxins and chemicals
- infection by viral agents
- immune mediated damage
- premature ageing of motor neurones
- loss of growth factors required to maintain motor neurone survival
- genetic susceptibility
In about 10% of cases, inherited gene mutations cause the condition.
Increasingly the thinking is that several factors contribute to MND developing in any one individual.
Who gets MND?
There are around 400 people living with MND in NZ at any given time, with on average 2 people dying each week and 3 people receiving a diagnosis.
The incidence rate of MND in NZ is higher than the rest of the world - researchers are trying to find out why so we can change it.
MND can affect adults at any age but most people diagnosed with MND are over the age of 40, with the highest incidence occurring between the ages of 50 and 70.
Key facts
- MND is an uncommon, but by no means rare disease.
- The number of people living with MND at any one time is approximately one in 15,000. In New Zealand over 400 people are living with MND.
- MND affects people from all communities.
- MND can affect adults at any age but most people diagnosed with MND are over the age of 40, with the highest incidence occurring between the ages of 50 and 70.
- Slightly more men than women get MND.
- A person’s lifetime risk of developing MND is up to 1 in 300.
- Most people with MND live for 20 to 48 months after symptoms begin. Five to ten percent of people with MND live for ten years or more.
- Each week MND will cause the death of 2 people in New Zealand.
- In approx. 90% of cases there is no known family history.
- In approx. 10% of cases the disease is known to be inherited.
- Around 35% of people with MND experience mild cognitive change, which can cause issues with planning and decision making. A further 15% will show signs of frontotemporal dementia, which causes more pronounced behavioural change.
New Zealand statistics
- In New Zealand an average of 144 people* are diagnosed with MND every year – about 3 in every 100,000 people. Internationally, the incidence of MND is much lower (approximately 2 in every 100,000 people).
- Approximately 400 people* in New Zealand are living with MND.
- Worldwide, 4 to 5 million people now alive today will die from MND.
- The median age of onset of MND in New Zealand is 67 years old*.
- 35% of people with MND in New Zealand* are aged under 65.
- 58% of people with MND in New Zealand* are male. 42% are female.
- Each year MND causes the deaths of an average of 120 people* in New Zealand.
- In 2011, one in every 202 deaths in New Zealand was caused by MND.
- A person’s lifetime risk of developing MND is up to one in 300 (reference: Table 2, Johnston 2006).
We don't know why the rate of MND in New Zealand is higher than the international average. There could be genetic reasons, environmental factors, or our health system could be better at diagnosing people with MND – or some combination of these factors.
* Numbers are calculated from only those people with MND who register as clients of Motor Neurone Disease New Zealand during 2019-20. We estimate over 90% of people with MND in New Zealand register with the charity.
Last updated:
29 August 2024