Diagnosing Parkinson’s earlier — so what?

What’s the current situation?

Currently, we can’t predict whether someone will develop Parkinson’s. This is because the exact causes of the condition are still being pieced together and research is still uncovering risk factors that might be involved. But many scientists believe that predicting who will develop Parkinson’s and diagnosing them earlier is the key to unlocking new and better treatments that could slow down its progression. Something that no current treatment can do. Something that might take time to discover. But something that would benefit the whole Parkinson’s community.

Brain cells that produce a chemical messenger called dopamine are affected in Parkinson’s and are involved in controlling movement, mood, sleep and much more. As the condition progresses, these brain cells are lost one by one. With fewer cells producing dopamine, gradually the levels of the chemical in the brain are reduced. Eventually, there is not enough dopamine for the brain to communicate effectively, and symptoms start to appear.

Scientists believe that people start to experience symptoms when around half of these dopamine-producing cells or more have already been lost. It is usually only at this point that people would visit their GP to share their symptoms and start the process of receiving a diagnosis. But by this time, the gradual loss of cells may have been happening for years.

Diagnosing Parkinson’s is not simple. There is no definitive test and it is estimated that more than 25% of people are misdiagnosed before they receive the correct diagnosis. This may be due to a number of things, from early symptoms crossing over with other neurological conditions, to a lack of understanding of Parkinson’s by healthcare professionals.

Read more about the early signs of Parkinson’s and how it is currently diagnosed.

Diagnosing Parkinson’s earlier

It’s therefore perhaps unsurprising that research is looking for a simpler way to diagnose Parkinson’s. With the hope of finding something that can diagnose people earlier, as well as being sensitive enough to predict who might be more likely to go on to develop the condition, before the loss of brain cells.

What impact would this have?

There is no doubt that improving diagnosis would be hugely beneficial. But, for a condition where we have no treatment that can slow or stop its progression, these benefits might not be immediately apparent.

So let’s cover some of the benefits that improving diagnosis could have for people with Parkinson’s:

Smoother diagnosis

A simple diagnostic test for Parkinson’s would help people have a smoother diagnosis, to get information, support and access to treatments and therapies more quickly.

Understanding early changes happening in the brain

If people were diagnosed earlier, this would allow for more research to study some of the earlier changes happening within the brain in Parkinson’s. This could help improve the understanding of the causes of the condition, and uncover some important targets to develop better treatments.

More efficient clinical trials

If a simple diagnostic test was developed which measured something found in the blood, saliva, or on the skin, this might also have the potential to track the progression of the condition. This is sometimes referred to as a biomarker: something that can be measured over time to show how a health condition is changing, progressing or indicating what level of intervention is needed. Something we don’t have for Parkinson’s.

This would allow people to have a better understanding of how their condition was progressing and it would be game changing for research. It would allow for a much easier way to measure whether a treatment in clinical trials was beneficial. Speeding up the search for better treatments and a cure for Parkinson’s.

New treatments more likely to succeed

As we have already covered, diagnosing Parkinson’s early would likely have little impact on how we treat Parkinson’s with the drug therapies currently in our arsenal. But it could give research into new improved treatments and cures a better chance of success.

As Parkinson’s progresses more brain cells are lost. But this is currently very difficult to monitor over time. This makes measuring the potential of new treatments in clinical trials challenging, as people taking part in studies may vary greatly in their symptoms and how many brain cells they have already lost. This might skew the results of clinical trials and give too much variability to properly prove the benefit of a treatment. Some people blame exactly this for the limited progress that recent clinical trials have had. Could it be that some of the drugs tested to date actually do have promise but we are not testing them in the most optimal way?

So, a test that diagnoses Parkinson’s early would identify a new group of people that could take part in clinical trials, where they have a more plentiful supply of cells for the treatment to work on. This could help more quickly identify promising treatments that could slow or stop the condition and even identify those that might stimulate regrowth of dopamine producing cells. This would be relevant to people no matter how long they have been diagnosed, making more treatment options available to everyone.

Listening to the voices of people with Parkinson's

Combining better diagnosis with research into therapies that can protect and repair the Parkinson’s brain gives real hope for changing the way we treat Parkinson’s. Something that can offer hope to the whole Parkinson’s community. And, one day, through early diagnosis and treatment, could there be a way to prevent people from developing Parkinson’s in the first place?

As this area of research develops, it will be important to continue to involve the voices of people affected by Parkinson’s and consider the ethical implications of receiving a diagnosis of Parkinson’s sooner. Tony Vernon, a researcher at King’s College London, has been working on biomarker research. He asked Parkinson’s UK for help to discuss his research with people from the Parkinson’s community.

"I had a very interesting conversation with someone living with Parkinson’s at a workshop run by Parkinson’s UK. He asked me why we wanted to develop biomarkers for a disease where there’s no cure. I thought it was an interesting question, and I wanted to see if people felt our research could be important."

• ‘Smelling Parkinson’s’ research could make it quicker and easier to diagnose Parkinson’s.
• Predict PD looking at 10,000 people without Parkinson’s to uncover common risk factors.
• Developing a diagnostic test for Parkinson’s: Detecting alpha-synuclein.
• From a sleep disorder to movement disorder, a new approach to stopping Parkinson’s.