Despite an estimated one in 100 Australians over the age of 60 living with Parkinson’s disease, the degenerative neurological condition remains difficult to diagnose and detect without the presence of physical symptoms.
That could all change after researchers at The Florey and Austin Health discovered it’s possible to detect the telltale signs of Parkinson’s disease decades before clinical symptoms appear. The findings could pave the way for more impactful screening programs and preventative treatments to reduce the impact of Parkinson’s disease.
Key points
Lead researcher Professor Kevin Barnham said the findings are a major breakthrough for Parkinson’s disease screening and it should ‘break down the door’ and result in far more accurate screening and treatments. This is particularly beneficial as it will raise awareness of just how early neurodegeneration begins.
“We all think Parkinson’s disease, Alzheimer’s disease and the like are diseases of the elderly and they’re not. That’s only when the clinical symptoms appear. Most of these diseases will start in midlife,” Professor Barnham explained.
“The average age of someone diagnosed with Parkinson’s is 61 and if neurodegeneration is starting 20 to 30 years earlier, that’s during their 30s or 40s.”
However, with a far more effective early screening program, preventative treatment could reduce the loss of brain cells and overcome the challenges of treating a disease that has seriously progressed.
“Developing therapies for people with clinically diagnosed Parkinson’s disease is incredibly tough. [By then] 85% of the neurons are gone. All of our strategies are what we call neuro-protection type strategies,” Professor Barnham added.
“The brain has a wonderful ability to adapt and cope with damage so when you see the clinical symptoms it means the brain has undergone significant damage. If there’s nothing to protect then treatments can’t work so we need to identify the disease much earlier.”
Given the onset of Parkinson’s disease is so hard to detect, related disorders could be the key to unlocking the door to early interventions.
According to the researchers, there’s a 33-year window in which brain cells die. Almost two-thirds of that degeneration occurs before an official Parkinson’s disease diagnosis can be made as healthcare professionals look for slowness of movement, muscle rigidity and tremors.
But by identifying other symptoms often written off as part of the ageing process, Dr Barnham said PET scans can be run on people who are at a higher risk of developing the disease.
“Part of the problem with early diagnosis is there are subtle symptoms and they’re not specific to Parkinson’s disease. The vast majority of people with early Parkinson’s disease will lose their sense of smell. There are things like constipation, sleep issues and loss of colour vision: most of us will pass it off as a consequence of getting older,” he said.
“None of them on their own will say you have Parkinson’s disease but they are an indication you’re a higher risk. The definitive proof is the PET scan. You can’t argue with it because it can track the key neurons within the brain that are lost due to Parkinson’s disease.”
Another early warning sign is rapid eye movement sleep behaviour disorder (RBD). RBD is the result of a deficiency in muscle atonia, which means when you experience REM sleep you will shout or thrash around while acting out vivid and unpleasant dreams.
Nine out of ten people with RBD will develop a Parkinsonian condition, such as Parkinson’s disease or Lewy body dementia, the second most common form of dementia. If these symptoms are identified by a sleep specialist or neurologist a PET scan could definitively identify Parkinson’s disease at least ten years earlier.
