When I was in my fellowship, one of the things I learned about Lewy body dementia was how many strange medical symptoms showed up first. Families were always taking their loved ones to the doctor. Here’s a strange medical symptom. Here’s another one. We don’t know what’s going on.
All of those symptoms happened before anyone realized it was Lewy body dementia.
If you’re caring for someone with Lewy body dementia, think back to how you got that diagnosis. Did you notice that in your loved one? A lot of confusing medical things happening first?
Part of what makes it confusing is that Lewy body dementia and Parkinson’s disease dementia look very similar. Both cause problems with thinking and reasoning that get worse with time. Here are five key differences that can help you tell them apart.
What Lewy Body Dementia Looks Like
In Lewy body dementia, we see significant decline in thinking and significant difficulty with reasoning.
One of the hallmark features is visual hallucinations, often of other people or animals.
We also see fluctuation. Your loved one might seem okay some days or some moments, and other days and other moments, not so okay. That’s really different from Alzheimer’s disease, where we tend to see slow, gradual decline and, for the most part, the same amount of problems day after day. If you’re still sorting out how Lewy body dementia differs from Alzheimer’s, I walk through both in the 5 most common types of dementia.
A lot of people with Lewy body dementia have a REM sleep disorder, where they’re almost acting out their dreams in their sleep. That symptom can show up before many of the thinking symptoms.
You’ll also often see parkinsonism. This is where your loved one has problems with movement very similar to someone with Parkinson’s disease. Maybe a tremor. Maybe rigid movements. Maybe trouble with balance. I explain parkinsonism in do all people with Parkinson’s disease get dementia?
The big difference is when those movement problems happen. In Lewy body dementia, they show up after or around the same time as the thinking problems.
What Parkinson’s Disease Looks Like
A classic sign of Parkinson’s disease is shaking in the hands.
Bradykinesia, which is slowness of movement, happens with Parkinson’s. So does rigidity, which is stiffness in the muscles.
In Parkinson’s disease, thinking problems can develop down the line, to the point that someone may develop dementia. But in the beginning, it’s really movement symptoms only. Not very much trouble with thinking at all.
5 Key Differences Between Lewy Body Dementia and Parkinson’s Disease
So how do you tell them apart?
1. Timing: When Thinking and Movement Problems Start
In Lewy body dementia, thinking problems happen earlier than the movement problems, or around the same time.
In Parkinson’s disease, the thinking problems happen well after the movement problems.
It’s all about timing.
2. Thinking First or Movement First
This is kind of the same thing, said a different way. In Lewy body dementia, thinking is affected first. In Parkinson’s disease, movement is affected first.
3. Hallucinations
Hallucinations are very common in Lewy body dementia, and they often show up early in the disease.
In Parkinson’s disease, they don’t always happen. When they do, they tend to come later on.
If your loved one is seeing people who aren’t there, I talk more about what’s happening in can people with dementia really see the dead?
Some medications can be dangerous for people with dementia, so it’s worth knowing which ones before anything new is prescribed. I go through them in medications that can be dangerous for dementia.
4. REM Sleep Disorder: Acting Out Dreams
The REM sleep disorder, where someone acts out their dreams in their sleep, is very common in Lewy body dementia. It’s less common in Parkinson’s disease.
5. Tremor, Slowness and Stiffness
Shaking in the hands is a classic sign of Parkinson’s disease, but it doesn’t always happen in Lewy body dementia. The same goes for slowness of movement. Stiffness happens in Parkinson’s disease and only sometimes in Lewy body dementia.
It’s Really About the Timing
Lewy body dementia and Parkinson’s disease share a lot of overlapping symptoms. What sets them apart is mostly which came first, the thinking problems or the movement problems, along with early hallucinations and that REM sleep disorder.
That’s the pattern to look for.
Thank you for what you’re doing for your loved one.
When the symptoms don’t line up neatly and the diagnosis takes a long time to get, it helps to have people to think it through with. Inside the Care Collective, we talk through exactly these kinds of questions every week, and how to take care of yourself while you live with the answers. You can learn more here.
