Memory Care Wisconsin

When Diseases Become Dementias: Parkinson’s and Huntington’s

When Diseases Become Dementias: Parkinson’s and Huntington’s

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Talking about dementia isn’t easy. Coping with it is even harder.

But as Michael J. Fox said,

“Acceptance doesn’t mean resignation.
It means understanding that something is what it is and there’s got to be a way through it.”

If we can grasp what’s happening, at least we can develop a plan for how to move forward. And that means figuring out what type of dementia we’re dealing with in the first place. Because there are several.

We’ve already talked about Alzheimer’s and Vascular and Lewy Body Dementias. But what about dementias that come from other diseases?

Frontida Assisted Living Facilities, such as the Frontida of Germantown, a Senior Living and Memory Care Community, provide you with posts like this one to help you live your best life.

Dementia by Any Other Name—Still Doesn’t Smell Sweet

“When dealing with a loved one with dementia, remember the person not the disease.
When dealing with challenging behavior, remember it’s the disease, not the person” (Unknown)

We’ve already established that dementia is not a natural part of aging. If you see Grandpa who may be living an at assisted living facility forgetting things, it’s important to figure out why. It might be as simple as a urinary tract infection or a problem with medication—or maybe he’s had too many life changes at once.

But sometimes it’s a by-product of another illness, like Parkinson’s or Huntington’s. And those kinds of dementias may need to be handled differently.

Parkinson’s Disease Dementia—When the Disease Takes Its Full Course

“We remember their love when they can no longer remember.” (unknown)

One million people in the US have Parkinson’s, and that number is expected to rise. Its most famous patient? Michael J. Fox.

But there have been many more: Alan Alda, George H. W. Bush, Billy Graham, Muhammad Ali, Jesse Jackson…

When Do Parkinson’s Dementia Symptoms Start?

Although Michael J. Fox was diagnosed early (age 29), most Parkinson’s Disease diagnoses come around sixty or older. Some research suggests that age is dropping down into the fifties range.

Either way, from disease diagnosis, Parkinson’s Dementia symptoms may not start for another ten years, but definitely won’t start for a year or more.

If they do? It’s not called Parkinson’s Dementia. It’s Lewy Body Dementia (DLB).

Hence the importance of keeping track of symptoms when you notice them.

It’s a chicken/egg-first situation. Both dementias are characterized by Lewy bodies in the brain. But they start in different regions.

  • DLB is dementia that affects the mind. As it attacks mental abilities, movement will become affected. You’ll see it as one of three patterns.
    • Dementia shows up first.
    • Dementia shows up at the same time as the physical symptoms.
    • Dementia shows up within one year of a Parkinson’s diagnosis (meaning the Parkinson’s diagnosis was really DLB).
  • On the other hand, Parkinson’s starts as a physical (movement) disease —which might, between one and ten years after diagnosis, become dementia.

In fact, Parkinson’s doesn’t always make that jump. 20-50% won’t. But 50-80% will.

What Are the Symptoms of Parkinson’s Dementia?

Because of the similarity to DLB—and the timing that sets them apart—let’s first look at the symptoms of Parkinson’s Disease.

You might see (on one or both sides of the body),

  • Tremors, shakiness
  • Muscle stiffness, hand cramps, shuffling steps, balance problems, stooped posture
  • “Frozen” facial expressions, muffled speech
  • Difficulty starting movements

All of these may start small, but they will progressively worsen. And as it spreads, it may affect mental functions—meaning dementia.

Those symptoms?

  • Struggling to pay attention, make sound judgments, or plan steps
  • Memory loss
  • Trouble interpreting visual clues
  • Visual hallucinations, delusions, or paranoia
  • Depression, irritability, anxiety
  • Sleep disturbances, like drowsiness during the day or rapid eye movement sleep disorder, which causes them to act out dreams. Those dreams are often unpleasant, meaning they may yell or suddenly—and violently—thrash their arms or legs.

What Causes Parkinson’s Dementia?

This is that frustrating broken record part…

They don’t know.

They know that with the disease, there are deposits or clumps of protein in the brain, and those clumps start in brain regions controlling motion. Those clumps appear to cause brain damage.

But because they don’t know why the clumps are forming, they don’t know how to stop them. They just treat symptoms. (Sorry…another broken record.)

Interestingly, some research shows

  • the more caffeine you drink, the less likely you are to get Parkinson’s Disease
  • the state or US region you live in may affect your chances (Northeast has more cases, with Vermont at the highest.)
  • there might be an herbicide/pesticide connection
  • men are 50% more likely to develop it than women

But again, there needs to be more research to understand why.

What Happens to the Brain in Parkinson’s Dementia?

Deep inside the brain, there’s a set of structures called the basal ganglia. When everything works well,

  • The basal ganglia receive information from the cerebral cortex,
  • Send that information to the brain’s motor centers,
  • And then return information back to the cortex so the cortex can plan what should happen next.

Simplified, think of a classroom.

  • The teacher has told all the students to sit quietly in their seats.
  • The principal calls on the intercom, asking the teacher to send a student to the office…
  • But the intercom is broken—or it’s garbled.
  • The teacher has no idea the student needs to go.
  • So the student doesn’t move.

That broken intercom is the basal ganglia—or a part of it. As Lewy bodies build up in that section’s nerve cells, the cells break down and die. They don’t produce neurotransmitters (chemical messenger dopamine) and the broadcast is cut. Meaning the next part of the line (the teacher) doesn’t know it needs to act.

If the student knows he needs to go, the teacher tries to stop him, and the student gets twitchy. (That characteristic Parkinson’s hand and head shake.)

The more nerve cells die, the harder it is to control movement—including other brain functions like memory, concentration, judgment… and the progression leads to dementia.

As complicated as that sounds, it’s still simplified. But the basis?

Parkinson’s inhibits movement.

How Long Does Someone with Parkinson’s Dementia Survive?

The older a person is when he’s diagnosed with Parkinson’s the worse his symptoms will be. Meaning he’s at a much higher risk of developing the dementia that can go with it.

Other than that, the speed varies.

There are no proven treatments to slow or stop the brain cell damage. They currently just treat symptoms, especially the twitchy part (“tremors”).

But it’s important to work carefully with the doctor. Some medications can make the situation a whole lot worse.

  • For example, while Parkinson’s Disease Dementia may cause hallucinations or paranoia, don’t use antipsychotic drugs. They can make it a whole lot worse, creating
    • worse Parkinson’s symptoms
    • sedation
    • struggles swallowing
    • life-threatening fever, rigidity, muscle breakdown (neuroleptic malignant syndrome [NMS])

Parkinson’s in itself is not considered a fatal illness. Instead, it causes other secondary issues, like pneumonia or instability. Falling might lead to surgery, infection, blood clots… i.e. the domino effect.

In the end, the stated life span with Parkinson’s Disease Dementia (PDD) seems to be debatable. But for an older person, research suggests added dementia cuts the time down by one to two years.

Huntington’s Disease (HD) Dementia—A Not-So-Helpful Mutant Ninja Turtle

“If and when the day comes that I may forget who you are,
please promise that you won’t forget that I am still me.”
(Mara Botonis, When Caring Takes Courage)

Remember the song “This Land Is Your Land”?  It was written by Woody Guthrie.

In the 1940s, his behavior changed violently, affecting his work, his relationships, his life. It wasn’t till the early 1950s that they figured out why.

He had Huntington’s Disease Dementia.

When Do Huntington’s Disease Dementia Symptoms Start?

Huntington’s Disease is much rarer than many of the other dementia’s we’ve talked about. In 2019, statistics stated HD diagnoses as

  • 2.7 people per 100,000 worldwide,
  • 10 per 100,000 in Europe,
  • 9 per 100,000 in America, and
  • fascinatingly, 21 per 100,000 in Egypt.

For those who have it, symptoms usually show up in their 30s and 40s, but they can start younger, even as early as two years old, or as late as 80.

What Are the Symptoms of Huntington’s Disease Dementia?

Like Parkinson’s, Huntington’s Disease is first a motor disease.

The biggest recognizable symptom?

  • Involuntary, uncontrolled, jerky, flailed movements of the arms, legs, head, face, and upper body.

But it also weakens

  • voluntary movement
  • speech and swallowing
  • eye movement
  • balance, posture, and gait

Yet while Huntington’s is physical, the cognitive (mental) issues can actually be the first noticed. Patients complain about

  • difficulties concentrating
  • trouble organizing
  • memory lapses
  • judgment issues and decision making

How quickly it progresses to what we’d label dementia depends on whether it’s the slow- or fast-moving version. But sooner or later, Huntington’s Dementia leads to a severe decline in thinking skills as well as psychiatric disorders, like

  • Anger
  • Irritability
  • Depression
  • Mood swings
  • OCD

All Huntington’s symptoms start out mild in its “early stage.” The person can generally care for his own needs (washing, dressing, eating…). But by the middle stage, he may need help.

What Causes Huntington’s Disease Dementia?

Different from what we know about Parkinson’s, Alzheimers, Lewy Body, and vascular dementias, Huntington’s Disease is a genetic disorder.

Most humans have 46 chromosomes (23 pairs), and Huntington’s has a mix-up in chromosome four.


You guessed it. No one knows. But it’s generally passed down from parent to child.

  • It affects men the same as women, in equal numbers,
  • But it does seem to hit European descendants more than Asians.

What Happens to the Brain in Huntington’s Disease Dementia?

Remember how the basal ganglia deep in the brain affects Parkinson’s? That same center comes to play in Huntington’s, too—just a different quadrant of it.

But this time, rather than creating a broken intercom so the teacher can’t hear the message…

  • Huntington’s throws the teacher out of the room altogether
  • and expects the Kindergarten Cop to teach the class. (You remember—Arnold Schwarzenegger and the completely out-of-control five-year-olds.)

So that’s the picture. What’s really happening?

In the brain, while some messages tell body parts to move, others tell them to be still. Parkinson’s attacks the former, Huntington’s, the latter.

That’s the end game. Let’s zoom in to understand how it happens.

  • The brain and spinal cord are made of neurons and nerve cells.
  • Those cells contain DNA, which, over time, needs to be repaired…a job usually done quickly and efficiently by healthy proteins.
  • But that faulty chromosome four from Huntington’s creates mutant proteins.
  • And mutant proteins don’t work so well. They make errors. The DNA mistakes build up, unusable.
  • The no-longer healthy cells die.

But those cells were responsible for sending those “stay calm” messages.

No more messages, no more calm.

And with all those cells gradually dying, the brain ends up with enlarged cavities (called frontal horns of the lateral ventricles.)

The cavities are normal. The enlarged size is not.

How Long Does Someone with Huntington’s Disease Dementia Survive?

The life expectancy for someone with Huntington’s can be anywhere from ten to thirty years.

Once again, Huntington’s Dementia  isn’t fatal.

It’s the by-products that are fatal.

  • Infections, like pneumonia
  • Injuries from falls
  • Heart failure

No, there’s no cure or drug to slow this dementia down either.

But those anti-psychotic drugs that make Parkinson’s so much worse? They actually help with Huntington’s.

The Long-Haul of Dementia

“You are NOT your illness. You have an individual story to tell. You have a name, a history, a personality.
Staying yourself is part of the battle.” (unknown)

No, it’s not easy talking about dementia. It’s not even easy writing about it.

But maybe you’re out there wondering what’s up with Grandpa. With Dad. Or maybe even with yourself.

Hopefully this series is helping you understand dementia a bit more, enough to develop a game plan, which may include memory care. We have one more set to talk about next time, so come back to read it. Meanwhile, if you know you need more help, Frontida is here for you.

Frontida Assisted Living in Wisconsin offers many senior living communities, including those dedicated to memory care. Memory care can be complicated and is tailored to every individual’s needs. Our dedicated memory care facilities are staffed with compassionate, caring staff who understand the complexities of memory care and can help. In addition, we offer a variety of activities for seniors and many amenities and programs at all of our senior living communities. Reach out to learn more, or schedule a tour today!

Need more information? Check out these other helpful posts to learn more about dementia.

Want to know more about dementia? Overwhelmed as a Caregiver? Check out these other helpful posts.

(A huge thank you to Photo by Manny Becerra on Unsplash for the featured image.)

Elizabeth Daghfal
• 9 min read

Elizabeth Daghfal is a writer, teacher, speaker, and community volunteer. When she isn't teaching or writing-- Who are we kidding? Her husband and five kids say she's ALWAYS teaching and writing. She has a passion to help people who are struggling and is happy to say her shoulders are drip-dry. Born and raised in the South, she now lives in Wisconsin and loves it--except for the fifteen months of winter. Read more about her at