First described as “shaking palsy” by James Parkinson more than 200 years ago, Parkinson’s was once thought of as just a movement disorder, causing the classic triad of tremor, slowness of movement, and muscle rigidity.
Yet only one-third of people with Parkinson’s ever shake.
Claire Bale is the associate director of research at the charity Parkinson’s UK. ‘People tend to have a very one-dimensional view of what Parkinson’s is,’ she says.‘They think it mainly affects older men and will cause people to shake and become slow and stiff, but in actual fact, it affects women and some younger people too, and there are more than 40 different symptoms.’
Around 153,000 people in the UK have Parkinson’s and one in 37 people will develop it during their lifetime. Cases are also predicted to rise to 172,000 by 2030 as the population ages. Here’s everything you need to know.
What is Parkinson’s?
People with Parkinson’s don’t have enough of the neurotransmitter dopamine because some of the nerve cells that produce it may have stopped working and this can affect movement.
‘Parkinson’s is a progressive neurological disorder that affects the brain, but also the body more widely,’ explains Professor Alastair Noyce, professor of neurology and neuroepidemiology at the Centre for Preventive Neurology at Queen Mary University of London.
‘The main thing that gives rise to the movement problems is loss of brain cells that produce dopamine, but Parkinson’s involves other groups of brain cells and also nerve cells in other parts of the body including the gut, and the heart, so it’s a whole-body disease.’
What are the symptoms of Parkinson’s?
Symptoms of Parkinson’s include much more than shaking. Prof Alastair Noyce says:
‘Parkinson’s also causes loss of speed of movement, you become more unstable and prone to falls. You may also notice changes to your speech, lose your sense of smell, or develop sleep disorders, constipation, bladder overactivity, anxiety, depression, and pain, a whole spectrum of movement and non-movement symptoms.’
The “mask of Parkinson’s” is another distinctive symptom, says Professor Tom Foltynie, professor of neurology in the clinical and movement neurosciences department at Queen Square UCL Institute of Neurology, London. ‘Your face can look miserable, and your facial expression isn’t as animated and people will often tell you to “cheer up”, but your facial expression isn’t necessarily linked to mood, but lack of movement in your facial muscles.’
Other symptoms include dystonia (muscle cramping) that affects the calves, feet, or toes and slow walking.
What are the early warning signs of Parkinson’s?
‘Constipation, sleep difficulties, anxiety and depression and loss of sense of smell are common early symptoms but also affect older people generally,’ says Professor Noyce. ‘These can be present for 5 or even 10 years before people get a diagnosis.
‘You may also notice subtle changes such as loss of arm swing on one side when you walk, and changes in your handwriting – it typically becomes small and untidy, words tend to be spaced out, but letters cramped together, and your handwriting tends to curve upwards.’
A marker for developing Parkinson’s in the future, is REM sleep behaviour disorder, where during your dreams you start ‘punching, kicking, and fighting off the baddies,’ adds Professor Foltynie. ‘Follow up on people who had these symptoms in sleep clinics found around 80 per cent conversion to Parkinson’s.’
How is Parkinson’s diagnosed?
Parkinson’s is diagnosed by a neurologist or a geriatrician with a specialism in Parkinson’s, most likely by examination and taking a history of symptoms.
‘If there’s any doubt, you may have a brain scan called a DaT scan which can confirm the loss of dopamine cells in the brain. A DaT scan doesn’t tell you much about the structure of the brain though, so you may need an MRI if you have other things going on (other processes as well as Parkinson’s),’ says Professor Foltynie.
New blood and spinal tap tests have been developed to detect Parkinson’s and some may be available within the next two years. One type of blood test developed by Japanese researchers can pick up a biomarker for ‘clumping’ of the protein alpha-synuclein, common in Parkinson’s patients, (the clumps can poison neurons and stop them producing dopamine).
Another potential blood test developed by researchers at the Duke University Center for Neurodegeneration and Neurotherapeutics in the USA can detect damage to cell mitochondria, potentially years before symptoms begin.
New research studies have also successfully used AI to detect early signs of Parkinson’s from eye scans, breathing patterns, and finger tapping tests. The finger tapping test is available now, though the researchers who developed it at the University of Rochester, USA, say it shouldn’t be used on its own yet without a physician’s input as it’s an emerging technology.
Does Parkinson’s lead to dementia?
Around 50 per cent of people with Parkinson’s could develop Parkinson’s dementia within 10 years of their diagnosis, says Professor Rimona Weil, honorary consultant neurologist at the National Hospital for Neurology and Neurosurgery in London and a clinician scientist at University College London.‘But people vary quite widely. Some people can have Parkinson’s for many years and not develop dementia at all, whereas others can develop changes in thinking and memory much earlier, even within two years of their diagnosis,’ says Professor Weil.
‘The biggest factor which predicts if you’re likely to get dementia is your age at diagnosis with Parkinson’s disease. The older you are the more likely you are to develop it, but there is still a lot of variability around this, and there are other factors that affect the likelihood, including genetic changes.’
There are two main types of dementia linked with Parkinson’s. Parkinson’s dementia is when dementia begins more than a year after the start of the movement symptoms of Parkinson’s.
Dementia with Lewy bodies is when the dementia happens before the movement symptoms of Parkinson’s, or within one year of them. They share the same symptoms, including difficulty with visual and practical tasks such as dressing or telling the time, slowness in thinking, organising things, and concentration problems. Other symptoms include visual hallucinations, changes in sleeping patterns and having more falls, as well as anxiety and depression.
These brain changes are caused by a combination of proteins that build up in the brain, including abnormal microscopic deposits of alpha-synuclein which become unfolded,which can form structures called Lewy bodies.
Professor Weil says treatments for dementia include drugs that make a neurotransmitter called acetylcholine more available in the brain. ‘People with Parkinson’s do very well on them.
‘Other non-motor symptoms that can develop include visual hallucinations. This is where people see animals or people that are not there, and these drugs can be effective for treating those symptoms too.
‘People can also get depression, anxiety, disrupted sleep, and dizziness on standing. These symptoms can all respond to treatment too. The approach I take in my clinic is to tackle lots of areas, each in a small way, which together can have a big impact on day-to-day life.’
What can cause Parkinson’s?
‘People say it’s due to a combination of genetics and environment, but I think that’s an oversimplification, there will always be a proportion of people for whom, even with a full understanding, no cause is clear,’ says Professor Noyce. ‘Sometimes it’s just stochastic – a random event that happened that’s bad luck but there’s no obvious cause.’
Some people report their Parkinson’s diagnosis follows a stressful life event such as divorce, bereavement, surgery, or losing a job, but experts believe most people will have had prior symptoms and the life event is merely the “straw that breaks the camel’s back.”
Research from Columbia University published in Neuron has added weight to a theory that Parkinson’s may begin in the gut, years before symptoms start. Researchers believe Parkinson’s could develop after a misdirected immune attack. The theory is the immune system detects alpha-synuclein proteins on the outside of neurons and attacks the cells, affecting their ability to produce dopamine.
Who is most likely to be affected?
Older people are much more likely to be affected by Parkinson’s than younger people. Figures from Parkinson’s UK show there are 1,800 people aged under 50 with Parkinson’s, compared to 28,300 aged 60 to 69, 62,400 aged 70 to 79 and 43,600 aged 80 to 89.
Men are more likely to have Parkinson’s than women, it’s thought sex hormones may protect women until menopause.
Genes can also play a role in determining whether you’ll get Parkinson’s or not. ‘Parkinson’s diagnosed before the age of 30 almost certainly has a genetic cause, whereas for people diagnosed in later life between 10 to perhaps 15 or 20 per cent will have a genetic predisposition,’ says Professor Foltynie.
Head injuries, repetitive head trauma, working with pesticides, and certain industrial chemicals are also associated with a higher risk of Parkinson’s.
What is life expectancy with Parkinson’s?
Parkinson’s itself doesn’t usually shorten your life, but some of the complications such as falls, and hip fractures may do.
Professor Noyce says: ‘How long people live with Parkinson’s varies, some people have very slow progression, and they die of something else with Parkinson’s rather than from it, and then you have people with a more diffuse, malignant form of Parkinson’s which is quite aggressive and leads to premature death.’
Can Parkinson’s be cured?
There’s no cure for Parkinson’s currently, but effective treatments are available to manage both motor and non-motor symptoms. Many people, like Dinah Hall who manages her condition with the Mediterranean diet, exercise, and medication, live for years with Parkinson’s managing their symptoms effectively.
How is it treated?
Dopamine replacement is the main drug treatment for Parkinson’s motor symptoms, the brain converts the drug into dopamine to make up the shortfall.
‘The best drug to control Parkinson’s motor symptoms is levodopa, this is the backbone of treatment and has been around since the 1960s, but there are lots of other treatments we can use alongside to manage motor and non-motor symptoms,’ explains Professor Noyce.
People usually start on 3 doses of levodopa daily, but as the progresses, they can find the effects last for a shorter period and they can need up to 9 to 10 doses a day, every 2 hours. ‘It becomes a heavy pill burden,’ says Professor Foltynie. ‘At that stage, we’ll start talking about using more advanced therapies, alongside tablets.’
Deep Brain Stimulation involves fitting a wire into the brain on each side, in the part of the brain that misbehaves when dopamine levels are low. Wires are tunnelled under the scalp behind the ear and connected to a pacemaker in the chest.
Other ways of delivering levodopa can include continuous infusions (carbidopa) directly into the stomach or via a butterfly needle under the skin.
Dopamine agonist drugs (including pramipexole and ropinirole) mimic the way dopamine works, reducing symptoms, including mood and behaviour. However, side effects can include sleepiness, and compulsive behaviours such as gambling, shopping, sex addiction and binge eating, as well as hallucinations.
News that the diabetes drug Exenatide may have slowed the progression of Parkinson’s symptoms in a phase 2 trial, has been seen as a potential gamechanger. A larger phase 3 trial, where the drug is compared to the best currently available treatment, to see if it slows down progression, is due to be published next year.
How can I prevent Parkinson’s?
You can’t avoid the biggest risk factor, which is getting older, but there are some actions that may be protective.
These include taking regular exercise, studies of large populations have shown people who exercise are less likely to develop Parkinson’s.
Avoiding developing type 2 diabetes when you are younger may also reduce your risk as research has shown people diagnosed in their 20s, 30s, and 40s, were at four times higher risk of developing Parkinson’s than those in the same age group who didn’t have type 2 diabetes.
Reducing exposure to industrial chemicals such as trichloroethylene, used for cleaning and degreasing metal, associated with a higher risk of Parkinson’s, may also help cut your risk. Wear a protective face shield and goggles and protective gloves, an apron, and boots if using them at work.
The herbicide paraquat used in farming, is also associated with a higher risk of Parkinson’s. It has been banned in the UK and EU since 2007, but still used in the US, where its use is restricted to licensed applicators.