A team of researchers has discovered that it is possible to measure the progression of dementia in people with Parkinson's disease by tracking iron deposits in the brain. Their findings appear in the Journal of Neurology, Neurosurgery and Psychiatry
Scans for dementia progression in Parkinson's usually focus on the loss of parts of the brain. However, brain imaging may detect these changes late in disease progression. As a result, doctors usually assess the progression of dementia by tracking symptoms. New research shows that scanning techniques may be able to detect dementia much earlier and more accurately, writes medicalnewstoday.com.
Dementia and Parkinson's
According to the National Institute on Aging (NIA), the characteristics of dementia include loss of the ability to think and memory. Other signs include changes in a person's behavior that affect their daily life. Different diseases can cause dementia. There is a strong link between Parkinson's disease and dementia.
Up to 50% of people with Parkinson's are also affected by dementia. People with Parkinson's may experience stiffness in their joints, shaking or tremors, and difficulty walking. They develop when a person's brain cells die, although it is not yet clear why this happens.
At its extreme, Parkinson's can damage large volumes of a person's brain. At this stage, the scan can detect this process. It is the loss of this brain volume that often causes the symptoms of dementia. According to the (NIA), people with Parkinson's often have a build-up of protein in their brains, something that is also seen in Alzheimer's patients.
The authors of the study, published in the "Journal of Neurology, Neurosurgery and Psychiatry", note that the presence of iron in the human brain - a natural part of the aging process - is associated with the increased presence of the protein.
Lead author of the study - Dr. Rimona Vale from "University College London" (UCL) says: "Iron in the brain is of increasing interest to people researching neurodegenerative diseases such as Parkinson's and dementias.
As we age, iron accumulates in the brain, but it is also associated with the accumulation of harmful brain proteins. So we're starting to see evidence that tracking it can be useful in monitoring the progression of the disease and potentially even in its diagnosis.”
New scanning technique
Instead of measuring the development of Parkinson's by scanning for brain volume loss, the researchers used a new technique called quantitative susceptibility mapping, which uses magnetic resonance imaging.
The team selected 97 people with Parkinson's who had been diagnosed with the disease within the previous 10 years, as well as a control group of 37 people who did not have the disease. The researchers tested both groups on their skills (thinking, memory) as well as motor functions that affect balance and movement.
The researchers then used the new scanning technique to measure the presence of iron in each person's brain. They compared the amount of iron with their scores on thinking, memory and motor function. Scientists have found that people who have higher amounts of iron in their brains perform worse in thinking, memory and motor functions depending on the location of its accumulation.
Better diagnosis of dementia?
The findings are significant because they give researchers a new way to identify the development of dementia far earlier and with greater accuracy than current techniques. This would be invaluable to researchers conducting clinical trials on the development of Parkinson's and dementia, but could also be potentially valuable for the early diagnosis of dementia.
According to the study's first author, George Thomas: "It's really promising to see measures like these that can potentially track the progression of Parkinson's disease, as it could help clinicians make better plans for treating people based on how their condition manifests itself”.
The team plans to continue to monitor the progression of dementia in their study participants to gain further information on how the progression of the disease relates to iron levels in their brains.