The Link Between Parkinson’s and Dementia

Matthew Ralph-Savage

January 22, 2021

One common factor between dementia and Parkinson’s disease is that they ravage the brain and a person’s behaviour. When a person is affected by both, it can be hard to tell the two apart. That’s because of the special bond that they share. Statistically speaking, data shows that of the one million people with Parkinson’s in the United States, 50 to 80 percent of them also have dementia.

The diseases overlap, but the reason largely remains uncertain.

Different studies have proven that Parkinson’s disease and dementia often overlap. However, many of these studies are still unable to pinpoint the force behind overlapping behaviors. That explains why physicians typically formulate different groups for the diseases during diagnoses.

Someone can have Parkinson’s and still showcase the presence of dementia in various forms. There are some situations where Parkinson’s becomes the baseline for dementia – Parkinson’s disease dementia. Some patients progress to develop a form of dementia known as Alzheimer’s.

The common trend among people with Parkinson’s is the development of Lewy body dementia not so long after diagnosis. The patients often notice a decline in cognitive functions, including delusions and hallucinations, even as they battle with Parkinson’s disease.

They have a set of shared symptoms.

Each of the diseases has unique characteristics. However, they share some symptoms, more so how the brain is impacted. The conditions fall under neurodegenerative categorization. The result is a state where protein abnormally accumulates in the brain to toxic levels.

For instance, dementia targets brain regions responsible for memory, such as the hippocampus, memory center, and temporal lobes. Parkinson’s, on the other hand, begins in the basal ganglia part of the brain. As it progresses, it can also end up affecting the memory center. In the long run, Parkinson’s disease can cause forgetfulness, which is an early symptom of dementia.

Having Parkinson’s does not imply you will develop dementia.

Parkinson's disease pathology may indeed result in different types of dementia. However, that does not imply having Parkinson’s immediately sets you on the path to get dementia.

According to the National Parkinson Foundation, an average of 30 percent of those with Parkinson’s do not develop dementia. The foundation further explains that as time progresses, those with Parkinson’s will still develop some form of cognitive impairment.

Know when to see the doctor

There are times when Parkinson’s disease does not sufficiently explain your sudden change in memory or mood. Under such situations, the patient should undergo additional diagnoses to explore the symptoms that Parkinson's is not enough to explain.

To determine the right time to visit the doctor for additional diagnoses, you can look out for more symptoms like:

    • Increased mood swings
    • High-level anxiety
    • Depression
    • Paranoia
    • Delusions
    • Hallucinations

The symptoms mentioned here cannot be effectively explained by Parkinson's disease and warrant other diagnoses, especially on various forms of dementia. In most situations, the family members may be quick at spotting the symptoms than the patient. The family should take the lead in asking for additional diagnoses.