King’s College London researchers have developed a method that could predict which Parkinson’s patients will experience cognitive decline, before they show any symptoms of memory problems.
The method uses widely available MRI scanning technology and could potentially be a cheap and easy-to-implement tool for doctors.
The study, published in the journal Brain, shows how a specific brain region deteriorates in Parkinson’s patients before they develop memory problems.
This is the first time a reliable biomarker for predicting cognitive decline in Parkinson’s has been identified.
Parkinson’s disease is one of the most common neurodegenerative disorders affecting one in 500 people.
During the course of the disease up to 80% of people with Parkinson’s disease develop cognitive decline, ranging from memory issues through to dementia.
‘Cognitive impairment is a major issue for people with Parkinson’s and has tremendous consequences for patients, families and healthcare services,’ says Marios Politis, Lily Safra Professor of Neurology & Neuroimaging from the Institute of Psychiatry, Psychology & Neuroscience.
‘Currently, there is no reliable way to predict cognitive impairment in Parkinson’s. Our method is realistic, cost-effective, non-invasive and shows genuine promise for use in clinical practice.’
The researchers analyzed brain imaging data from 304 patients who were not taking Parkinson’s medications and 167 healthy controls, drawn from the Parkinson’s Progression Markers Initiative (PPMI), sponsored by The Michael J. Fox Foundation for Parkinson’s Research.
The researchers used MRI imaging, a technology that is widely available in hospitals, to monitor changes in the brains of Parkinson’s patients.
The MRI scans revealed a brain region called the nucleus basalis of Meynert that started to degenerate in patients before they began to show any symptoms of cognitive decline.
The nucleus basalis of Meynert produces a neurotransmitter called acetylcholine, and previous research has shown Parkinson’s and Alzheimer’s patients have reduced levels of acetylcholine.
Understanding which people with Parkinson’s disease are going to experience cognitive decline would not only help doctors manage patients but may also enable clinical trials for preventative drugs.
The challenge in developing preventative drugs is knowing when to treat patients, and whether the drugs would have been effective if given at the correct time to the correct people.
‘When disease modifying drugs become available, patients can potentially be treated in the crucial time before the development of symptoms, prolonging their quality of life,’ says Professor Politis.
While the results hold significant promise, they need confirmation in further studies before the method can be used by doctors for screening Parkinson’s patients.