On an early morning jog, keen runner Katy O’Malley felt a sudden, nagging pain around her left big toe. She ignored it, hoping it was the sort of minor twinge often picked up while exercising.
‘It started to affect my big toe and the two toes next to it – but I just hoped it would sort itself out,’ says Katy.
But fast-forward some 20 months later – and Katy was diagnosed with Parkinson’s disease: her foot discomfort had been an early sign of it. She was just 42.
Around 166,000 people in the UK live with Parkinson’s, a progressive disease where a build-up of a misfolded protein in the brain destroys cells that make dopamine. This chemical transmitter controls movement as well as the reward and motivation centre of the brain.
As a result, the main symptoms include tremors, stiffness and slow movement. It can also cause anxiety, depression and insomnia.
The young-onset form – where it affects someone under the age of 50 – accounts for about 6 per cent of cases.
But recent research suggests the incidence of young-onset Parkinson’s is becoming significantly more common, with cases more than doubling from 1990 to 2021, reported the journal npj Parkinson’s Disease. Exactly why is unclear, although theories include better detection and stronger genetic links in younger groups.
And the causes, symptoms and even how well medication works (more on this later) can be slightly different in young-onset Parkinson’s, explains Professor Roger Barker, a consultant neurologist at Cambridge University Hospitals NHS Foundation Trust, which makes research into this sub-group particularly important.
When the pain in her toe didn’t ‘sort itself out’, as she expected it to, after six weeks Katy O’Malley saw a physiotherapist who suspected a neuroma (thickening of tissue around a nerve in the foot)
‘The younger you are when you get Parkinson’s, the more likely it’s caused by genetics rather than a mix of more complex genetic and environmental factors – which is the best explanation we have for Parkinson’s seen in older people.
‘And part of the problem is that diagnosis takes longer in younger people because if you’re 35 and see your GP with an odd pain in your foot – a classic early sign – they’re not going to think about checking for Parkinson’s. Whereas if you’re 75, they will.’
For Katy, when the pain in her toe didn’t ‘sort itself out’, as she expected it to, after six weeks she saw a physiotherapist who suspected a neuroma (thickening of tissue around a nerve in the foot).
After treatment made no difference, she was referred by her GP to an NHS orthopaedic consultant, who was also unable to find the cause.
‘After that, I really began to worry,’ says Katy, now 48, a local government policy officer who lives in Liss, Hampshire, with husband Ben, 52, a market research director, and their children, aged 15 and 13.
Then Katy noticed a tremor in her left forefinger: ‘At that point I just knew in my gut that something was seriously wrong,’ she says, and she went to see her GP once more – who referred her to a neurologist. ‘She examined me and she said: “I don’t think it’s benign”,’ recalls Katy.
‘Hearing that was terrifying. You never want a neurologist to say that. She sent me for an MRI and other brain scans – and while waiting for the results, I thought I was dying of something.’
It took about six months for all her results to come through.
By the time Katy saw the neurologist again in October 2020, her symptoms had worsened – including her left arm now not swinging when she walked (another indication of Parkinson’s). Her neurologist explained that while an MRI scan showed nothing wrong, a DaTscan – a more detailed brain test which uses a radioactive dye – revealed a lack of dopamine-producing cells in the area that is key for movement.
She was told her initial foot issue was due to dystonia, a painful muscle spasm common in young-onset Parkinson’s.
‘By then I’d been Googling and worked out what it was,’ says Katy. ‘I was actually relieved to finally know the cause. Parkinson’s is devastating – though I told myself there are worse brain diseases to have.
‘But the fear and uncertainty I felt was overwhelming at times.
‘My children were so young [then aged ten and seven], that for two years I didn’t tell them about the diagnosis. It was important for me to continue to live as normally as possible.’
Katy now takes levodopa, one of the main drugs used to treat Parkinson’s. The body converts it to dopamine, which reduces symptoms such as stiffness.
But while levodopa is the ‘best treatment we have’, says Professor Barker, ‘treating younger patients with it can be more challenging’. He adds: ‘Often patients with young-onset Parkinson’s don’t want to take levodopa because over the years it leads to a side-effect of dyskinesia [involuntary and abnormal muscle movements]. So they want to start the clock on developing these as late as possible.’
Research into drugs for Parkinson’s has shifted direction in recent years, with greater emphasis on looking for a cure, as a new paper published in the Journal of Parkinson’s Disease this year highlighted.
An analysis by the charity Cure Parkinson’s of 444 worldwide clinical trials between 2015 and 2024 showed half were for drugs to slow, stop or reverse the disease.
Meanwhile, a major £26million initiative is running across 40 NHS sites to speed the hunt for a cure, by scrutinising several candidates at the same time.
Dr Simon Stott, director of research at Cure Parkinson’s, says: ‘Usually during clinical trials, a single drug is tested against a placebo and this must be done each time the researchers want to test a new drug.
‘It’s like building a football stadium to play a single match and then dismantling it – only to do it again for the next one.
‘So this is a very different approach which is already proving successful for cancer drug research, for instance.’ Professor Barker says there’s particular research interest in young-onset Parkinson’s because its strong genetic factor makes it ‘ideally placed for new, precision-type treatments where the genes are modified and injected directly into the brain’.
Katy became involved in clinical trials soon after her diagnosis. A friend sent her a link about Cure Parkinson’s and the research it was funding. ‘It was just the tonic I needed as it gave me a sense of control rather than just sitting back and letting this disease take over,’ she says.
The first study she joined was for an advanced stage, two-year trial for a drug called exenatide, a GLP-1 receptor agonist usually used to treat type-2 diabetes which had shown promise for improving motor function.
Researchers were investigating whether it could slow the progression of the disease.
Unfortunately, the trial did not reach its hoped-for conclusion – ‘but it ignited a passion in me for the importance of research’, says Katy.
She has since put herself forward for three further drug trials to see if she’s eligible, as well as psychological studies for people with Parkinson’s.
Earlier this year she donated biological samples including blood for a trial looking at inherited Parkinson’s.
Katy was told her initial foot issue was due to dystonia, a painful muscle spasm common in young-onset Parkinson’s (picture posed by model)
Katy also feels a ‘responsibility’ to be involved in clinical trials because she has children. ‘I have a LRRK2 and a GBA1 gene variant so there is a 75 per cent chance that each of my children will carry at least one of these,’ she says.
Children are not tested for gene variants but could receive checks when they reach adulthood. It is a decision her children will make for themselves, Katy says.
She adds the levodopa allows her a ‘window’ of about two hours when ‘I can feel like myself again’.
‘After a dose, I can go for a four-mile run or a walk with our dog Simon,’ she says.
But the dyskinesia side-effect is ‘horrendous’. ‘I can’t be in a queue or a shop without people staring at me as I can’t stay still – it’s so embarrassing.
‘It is also dangerous as it throws me off my balance and I can fall over. I have to carefully plan my day as the effects of the levodopa wear off,’ says Katy, who works three days a week from home.
‘So I might be able to walk to a restaurant – but if the meds wear off, I might not be able to walk back home.’
She also suffers insomnia, slurred speech and her toes are so clawed she has to manually uncurl them soon after waking each morning.
‘Parkinson’s now governs my life,’ she admits. ‘But I’m very lucky to have supportive family and friends. And I am keen to increase participation in clinical trials: I want to be able to look my children in the eye and say that I’ve done everything I can to help further research.’
To find out about ongoing trials, visit cureparkinsons.org.uk
