Experts pinpoint everyday trigger for terrifying locked-in syndrome

People with higher levels of toxic metals lurking in their blood or urine may be at greater risk of the life-destroying disorder amyotrophic lateral sclerosis (ALS), alarming research today suggested. 

Scientists have long linked ALS, also known as ‘locked in syndrome’ with toxic substances in the environment including exposure to metals as well as pesticides. 

The disease, which can lead to paralysis and eventually death, claimed the life of Sandra Bullocks’ partner last year and was famously suffered by the acclaimed scientist Stephen Hawking.

But now researchers in the US believe higher exposure to metals in the blood and urine could also pose a shorter ALS survival risk. 

Scientists have long linked ALS, also known as ‘locked in syndrome’ with toxic substances in the environment including exposure to metals as well as pesticides. ALS was famously suffered by the acclaimed scientist Stephen Hawking 

The disease, which can lead to paralysis and eventually death, claimed the life of Sandra Bullocks’ partner Bryan Randall (pictured with Sandra Bullock in 2018) last year

The ALS Association revealed that the death of Sandra Bullock’s partner Bryan Randall sparked a 500 per cent increase in donations to the charity. His family asked for people to donate to the ALS Association instead of sending or buying flowers

Experts today claimed the probe showed it was vital to limit high risk activities associated with metal exposure, like machining activities, and said further research was ‘essential’ to improve future treatments. 

Dr Stephen Goutman, senior study author and and associate director of the ALS Center of Excellence at University of Michigan, said: ‘Strengthening our understanding of the importance of exposure to metals as a risk factor for ALS is essential for future targeted prevention of the disease and improved therapeutic strategies.

‘Several epidemiologic studies have linked metal exposure to ALS risk. 

‘Nonetheless, it remains critical for us to understand how these metal mixtures associate with ALS risk and survival and to identify who is at greatest risk of exposure or who is most susceptible to the exposure.’

Dr Dae Gyu Jang, co-author and postdoctoral fellow in neurology at the University of Michigan, added: ‘These findings emphasize the necessity of accounting for occupational and environmental factors when evaluating a person’s overall exposure risk.

‘Our future research will further focus on what exposures have the strongest associations and their implications on the disease.’

Also known as motor neurone disease (MND), ALS is a rare condition that progressively damages parts of the nervous system. 

It occurs when specialist nerve cells in the brain and spinal cord called motor neurones stop working properly — known as neurodegeneration. 

Life expectancy for about half of those with the condition is between just two and five years from the onset of symptoms.

However, some people may live for up to 10 years, and, in rarer circumstances, even longer.

Around 5,000 people in the UK and 30,000 in the US have the condition. 

Locked-in syndrome (LIS) is a rare neurological disorder that can also occur in some progressive cases of ALS.

In the study, the researchers measured metal levels in plasma and urine samples from over 450 people with ALS and nearly 300 people without the condition.

They found that elevated levels of individual metals, including copper, selenium and zinc, significantly associated with higher ALS risk and earlier death.

Using these results to create environmental ALS risk scores, they discovered that mixtures of metals in plasma and urine are linked to around a three-times greater risk for the disease.

Writing in the Journal of Neurology, Neurosurgery, and Psychiatry, they added that participants working in occupations with a higher likelihood of metal exposure had increased levels of metal mixtures in their blood and urine. 

Up to 300 Brits and fewer than 1,000 Americans are estimated to be living with locked-in syndrome.

It is caused by damage to the brainstem that contains nerves that transmit information to other parts of the body.

Such damage usually occurs due to a lack of blood flow or bleeding following serious physical trauma.

Locked-in syndrome exists on a scale with some patients able to move more parts of their body than others. However, there is currently no cure for the condition. 

Many patients are confined to their beds, needing constant care and are only able to breath or eat and drink via special medical tubes.

Instead, treatment focuses on helping develop any small voluntary actions that are available to patient such as finger movement, swallowing and making sounds.