13/04/2026
Parkinson’s disease affects around 145,000 people in the UK.
At first it mainly causes problems with movement. However, after a few years some people also start to have problems with thinking, memory and perception.
These symptoms are mild at first, and for many people, they don’t get much worse. However, around a third of people with Parkinson’s eventually develop dementia.
The disease that causes Parkinson’s is very similar to the one that causes dementia with Lewy bodies.
In fact, many scientists consider these two conditions to be the same disease but with different starting places in the brain.
In Parkinson’s dementia, the most common early symptom you might spot is problems with movement. Over time, someone may experience more common dementia symptoms like problems with thinking, memory and perception. But for dementia with Lewy bodies, it’s typically the other way around.
Symptoms vary and can change quickly from hour to hour. However, most people have symptoms very similar to those of dementia with Lewy bodies.
If you’re worried about Parkinson’s disease or dementia, speak to your GP, or give our Dementia Support Line a call on 0333 150 3456.