A simple skin swab based on the powers of ‘super smellers’ could detect devastating Parkinson’s disease up to seven years before symptoms appear.
Parkinson’s is an incurable neurological condition where parts of the brain become damaged over years, and which blights the lives of millions.
Patients suffer progressive tremors and movement problems that can eventually rob them of their independence.
While scientists have known for years that some people have the amazing power to sniff out Parkinson’s before obvious signs develop, they have struggled to create a test that can do the same.
But in a breakthrough, experts from the University of Manchester have come a step closer to making this a reality.
They discovered compounds found in sebum—an oily substance naturally produced by the skin—contained tiny traces of chemicals that indicate a person could be in the earliest stages of Parkinson’s.
While the disease isn’t curable early diagnosis is considered key to helping patients access treatments that can combat serious symptoms and maintain their quality of life for as long as possible.
Publishing their findings in the journal npj Parkinson’s Disease experts analysed skin swabs taken from 46 Parkinson’s patients, 28 healthy volunteers and 9 people with a condition called isolated REM Sleep Behaviour Disorder (iRBD).
Symptoms can include uncontrollable tremors, slow movements and muscle stiffness, but experts say they often only appear when about 80 per cent of the nerve cells have been lost
Super Smeller Joy Milne (pictured on ITV’s This Morning in October 2019) first discovered she can smell Parkinson’s when her late husband Les was diagnosed in 1980s
Mrs Milne’s ability was backed up in a scientific trial where she was able to sniff the difference in swab tests taken from Parkinson’s patients and healthy controls. Pictured here with her husband Les
iRBD is a sleep disorder where people often physically act out their dreams, sometimes violently, while asleep and is a known to be a potential early warning sign of Parkinson’s.
Results showed that iRBD patients had distinct chemicals in their sebum that differed from healthy volunteers, but these weren’t yet at the level as those with Parkinson’s.
This, the researchers suggested, indicated early-stage Parkinson’s was leaving tiny, but detectable, traces in the body up to seven years before the appearance of symptoms that would lead to a diagnosis.
To back up their findings scientists also referred to Parkinson’s ‘super-smeller’ Joy Milne.
Mrs Milne, a former nurse from Perth, Scotland, discovered she could smell the disease when she noticed a change in her late husband Les’ scent a decade before he was diagnosed in 1985, describing it as a ‘musky, greasy’ odour.
The grandmother’s ability was backed up in a scientific trial where she was able to sniff the difference in swab tests taken from Parkinson’s patients and healthy controls.
In the new study, Mrs Milne was able to distinguish both swabs taken from iRBD patients and those with Parkinson’s.
But even more interestingly she was able to spot two iRBD patients who had undiagnosed Parkinson’s, whose condition was confirmed at their next appointment.
Actor Michael J Fox (pictured here earlier this year) was diagnosed with Parkinson’s disease at just 29 years old. He now advocates for more research into the condition
Professor Perdita Barran, an expert of mass spectrometry—a scientific field on the study of tiny particles like those detected by scent— at Manchester, hailed the results.
‘This is the first study to demonstrate a molecular diagnostic method for Parkinson’s disease at the prodromal or early stage,’ she said.
‘It brings us one step closer to a future where a simple, non-invasive skin swab could help identify people at risk before symptoms arise allowing for earlier intervention and improved outcomes.’
As sebum is easily collected by a simple swab of a patient’s face and back—and doesn’t need to be stored at cold temperatures for transport for analysis—the hope is that a final test will be easy and cheap for medics to use.
It would represent a revolution for Parkinson’s diagnosis as there is currently no definitive test for the condition.
Currently diagnosis is normally based on the development of later stage symptoms like tremors after other potential health conditions have been ruled out.
Parkinson’s charities estimate over one in four patients with the condition are misdiagnosed before getting the correct diagnosis.
The researchers say they are continuing to develop and improve the sebum-based test with the goal of launching it to real-world clinical settings.
Dr Drupad Trivedi, an expert in analytical measurement sciences at Manchester, added, the team was keen to hear from other potential ‘super smellers’, like Mrs Milne, who might be able to detect other diseases.
About 90,000 Americans and 18,000 British people are diagnosed with Parkinson’s every year, with more than 10million patients estimated to have the condition worldwide.
The disease costs the NHS more than £725million a year.
Early signs of Parkinson’s include a tremor, stiffness, slowness of movement and loss of smell.
Balance problems such as issues with coordination and muscle cramps are other common signs.
Patients can also, as a consequence of their disease, frequently suffer from mental health problems like depression and anxiety.
Parkinson’s is caused by the death of nerve cells in the brain that produce dopamine, a chemicals which controls movement.
Experts are still working to uncover what triggers the death of these nerves.
However, current thinking is that it’s due to a combination of genetic changes and environmental factors.
Risk of developing the condition broadly increases with age, with most patients are diagnosed over 50.
‘HE BEGAN TO SMELL UNPLEASANT TO ME’: NURSE DETECTS ‘MUSKY, GREASY ODOUR’ IN HER HUSBAND A DECADE BEFORE HE WAS DIAGNOSED
Mrs Milne noticed a ‘musky, greasy sort of odour’ in her husband Les (pictured). He was diagnosed a decade later and died in 2015 aged 65
Joy and Les Milne were childhood sweethearts who started dating at just 16.
When they reached their mid-30s, Mrs Milne – then a nurse – noticed a change in her husband’s odour.
‘He began to smell unpleasant to me and although we always were a loving couple, I was always aware of it,’ she said.
Mrs Milne described it as ‘musky, greasy sort of odour’, and would nag her husband to shower and brush his teeth more.
It was a decade later, at the age of 45, that Mr Milne was finally diagnosed with Parkinson’s after battling the tell-tale tremors, as well as fatigue and impotence.
Around the time of his diagnosis, Mr Milne’s personality changed, with the once gentle doctor lashing out at his wife on two occasions, once bruising her face.
‘As it was happening, his eyes looked blank, like he had no idea what he was doing,’ Mrs Milne said.
Over the next 20 years, the former swimmer and water-polo player became dependent on a walking frame.
He was even forced to retire from his job as a consultant anaesthetist due to his tremors and reduced concentration.
The couple (pictured on their wedding day) started dating at just 16 years old
In 2005, the couple moved back from Cheshire to their native Perth, Scotland, where Mrs Milne made the connection between Parkinson’s and her husband’s odour while accompanying him to a support group.
‘After we left I said to Les: ‘The people with Parkinson’s in that room smelt the same as you’,’ Mrs Milne said.
In 2010 she contacted the Parkinson’s researcher Tilo Kunath, of Edinburgh University, who put her skills to the test a year later.
After asking 12 volunteers to wear a T-shirt for 24 hours, Mrs Milne correctly identified the disease status of 11 of them – with the only one she got wrong being diagnosed the following year.
Shortly after, Mr Milne lost his battle with Parkinson’s in 2015 aged 65.
Mrs Milne has since been keeping to her husband’s dying wish of assisting research into the ‘smell of Parkinson’s.
But Parkinson’s is not the only disease Mrs Milne can detect.
As a student nurse, she claims spotted those with gallstones before they were diagnosed.
And while training as a midwife, she could tell whether a woman smoked or had diabetes by the scent of her placenta.
