By Margarita Tartakovsky, M.S.
Psychosis doesn’t just affect
individuals with psychiatric disorders such as schizophrenia. It also affects
other illnesses, including Parkinson’s disease (PD), a degenerative disorder
that disturbs movement and balance.
Over five million people worldwide
have PD, struggling with symptoms such as shaking, stiffness, slowness of
movement and instability.
“Psychosis in Parkinson’s disease is
very common,” according to Michael S. Okun, M.D., national medical director at
the National
Parkinson Foundation and author of the Amazon no. 1 bestseller Parkinson’s Treatment: 10 Secrets to a Happier Life.
In fact, psychosis may affect 1 in 5
Parkinson’s patients, he said. And as many as 2 out of 3 patients may
experience minor symptoms, “such as non-bothersome illusions.” (An example is
“seeing something in the corner of your eye that may not be there, [such as] a
bug in the sink for an instant.”)
“Patients primarily experience visual
hallucinations,” said James Beck, Ph.D, the director of research
programs at Parkinson’s
Disease Foundation. A smaller number of patients – 10 to 20 percent
– experience auditory hallucinations, he said.
Some patients also may experience
delusions, or fixed false beliefs. According to Dr. Okun in his piece on managing psychosis in PD:
“Delusions are usually of a common
theme, typically of spousal infidelity. Other themes are often paranoid in
nature (such as thinking that people are out to steal from one’s belongings, or
to harm or place poison on their food, or substitute their Parkinson
medications, etc.) Because they are paranoid in nature, they can be more
threatening and more immediate action is often necessary, compared to visual
hallucinations (Zahodne and Fernandez 2008a; Zahodne and Fernandez 2008b;
Fernandez 2008; Fernandez et al. 2008; Friedman and Fernandez 2000). It is not
uncommon that patients actually call 9-1-1 or the police to report a burglary
or a plot to hurt them.”
In the early stages of psychosis,
patients tend to have insight into their symptoms, Beck said. In other words,
they realize that what they’re seeing (or hearing) isn’t actually there. But
this may worsen over time. According to Okun in the same piece:
“At later stages [of psychosis],
patients may be confused and have impaired reality testing; that is, they are
unable to distinguish personal, subjective experiences from the reality of the
external world. Psychosis in Parkinson’s disease patients frequently occurs
initially in the evening, then later on spills into the rest of the day.”
Psychosis typically doesn’t develop
until several years after a person has been diagnosed with PD, Beck said.
(If hallucinations are present from
the start, then it may be another condition. For instance, Lewy body dementia
“might cause psychosis and can be misdiagnosed as Parkinson’s disease.”)
These symptoms can be incredibly
disturbing for both patients and caregivers, Beck said. They also make
caregiving more challenging and overwhelming. Some research has found that
hallucinations were the strongest predictor for institutionalization.
What Triggers Psychosis in
Parkinson’s Disease
“There are many potential triggers
for hallucinations or other psychotic phenomena and these include medications,
infections and sleep deprivation,” Okun said. Particularly in the elderly
population, stress, dehydration and urinary tract infections can spark
hallucinations, Beck said.
Medications that treat Parkinson’s
disease increase levels of dopamine in the brain. This is important, because
the disorder involves the malfunction and loss of neurons that produce
dopamine. Dopamine relays messages to the substantia nigra and other parts of
the brain, which control movement and coordination.
But dopamine also plays a pivotal
role in hallucinations, Beck said. In other words, by boosting dopamine levels,
these medications improve motor symptoms, and may produce psychosis.
Parkinson’s disease itself may lead
to hallucinations. As the disease progresses, it can impair cognition and
visual processing, leading to dementia, Beck said.
Treating Psychosis in Parkinson’s
Disease
“Psychosis does not always require
treatment, particularly if hallucinations are non-bothersome,” Okun said. If it
does require treatment, doctors try to pinpoint what’s causing the
hallucinations. For instance, if it’s an infection, they may prescribe
antibiotics. If it’s a sleep disorder, they may prescribe a sleeping aid.
To reduce hallucinations directly,
atypical antipsychotics, such as clozapine (Clozaril) and quetiapine
(Seroquel), may be used, Okun said.
To date clozapine is the only
medication shown to be effective in double-blind studies, Beck said. (This 2011
paper
reviews the research for clozapine along other medications.) “Though given at
very low doses for Parkinson’s, clozapine may cause a dangerous drop in white
blood cell count. Therefore, patients must undergo regular blood monitoring.”
First-generation or typical
antipsychotic drugs, such as haloperidol, are not prescribed for psychosis in
PD. In fact, this is actually dangerous, because these drugs lower dopamine and
can induce a “neuroleptic crisis,” Beck said.
He also mentioned a new drug called
pimavanserin, developed specifically for psychosis in Parkinson’s disease. (It
hasn’t received FDA approval yet.) Instead of modulating dopamine, Beck said,
this drug targets serotonin. Some research has suggested that activating
particular serotonin receptors can lead to visual hallucinations. “Shutting
down the activity of this receptor and neurons associated with it may alleviate
hallucinations [without] impacting motor performance.”
Psychosis is a serious problem for many
patients with Parkinson’s disease. Beck stressed the importance of telling your
doctor right away if you’re struggling with hallucinations or other psychotic
symptoms. “Early intervention [or] treatment can make a difference, improving
quality of life for both the person with PD and their caregiver.” He also
encouraged readers to work with a movement disorders specialist, who will have
expertise in both motor and non-motor symptoms.
Additional Information
▪
Both the Parkinson’s Disease Foundation (800-457-6676)
and the National
Parkinson Foundation (800-473-4636) have helplines for more
information.
▪
Parkinson’s Disease Foundation
includes over 30 seminars you can watch with PD experts on
research, treatment, non-motor symptoms and more.
▪
National Parkinson Foundation
features a helpful outline of psychosis in PD.
▪
The Michael J. Fox Foundation offers a
wealth of information, including articles on diagnosis, treatment and the
latest science.
Last reviewed: By John M. Grohol,
Psy.D. on 4 Aug 2015
Published on PsychCentral.com. All
rights reserved.
http://psychcentral.com/lib/what-you-need-to-know-about-psychosis-in-parkinsons-disease/
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