PD Related Psychosis

by Suketu M Khandhar, MD & Michel Medina, MD Kaiser Permanente Sacramento

“Creativity and Psychosis often go hand in hand.” This line can be heard as you watch the trailer for the Netflix show, The Queen’s Gambit (great show by the way). What is psychosis? As taken from the dictionary, psychosis is a severe mental disorder in which thought and emotions are so impaired that contact is lost with external reality. Sounds scary and to be honest, it can be, for both the individual and their loved ones.

Marie Curie once said, “Nothing in life is to be feared, it is only to be understood. Now is the time to understand more, so that we fear less.” So, let’s dissect this condition.

Psychosis in Parkinson’s disease is not uncommon. It is more likely to occur in the later stages of the disease and can be associated with Parkinson medications, as well as the natural progression of the condition itself. The underlying pathology of psychosis is less understood. Epidemiological research puts the prevalence of significant PD related psychosis at 10%, however we feel it’s more common than that. We also feel there is a range to the symptoms. Not everyone with PD related psychosis fits the definition above.

About 50% of all patients with Parkinson’s disease will experience hallucinations and/or delusions over the course of their disease. It is more likely to occur in those who are older, who have had a longer duration of disease, who are on large pulse doses of dopaminergic medication and who have ongoing REM Sleep Behavior Disorder (this is when you unknowingly act out your dreams during sleep and at times shout out). Some may experience visual hallucinations, which is an experience involving the altered visual perception of something that is not actually present. Some may

experience illusions, which is the experience of wrongly mistaking something for something else. And some may experience delusions which are the experience of firmly thinking things that are not anchored in reality. Not everyone experiences all these and there is a spectrum to these symptoms.

From our experience, the range of psychotic experiences seen in PD can be quite variable. For some, it could be mild and not troublesome: for example, visual perceptual changes (e.g. brief sensation of a presence or a shadow) or complex, formed, brightly detailed visual hallucinations (small animals or children playing in the yard) and may carry a Lilliputian quality to them (Lilliputian hallucinations are taken from the book ‘Alice In Wonderland’ – remember how characters became smaller in the story).

But for other people with PD and psychosis, the experience can be much more severe and include ‘Phantom Boarder Syndrome’ whereby the visual hallucinations are seen asintruders in the house, and the individual no longer recognizes the “intruders” as hallucinations, but as reality.

Care-partners have told us how their loved ones have set the table for 8 when only 2 of them live in the house. To make things worse, troublesome delusions and hallucinations can be very paranoid in nature. As you can imagine, this can be scary, anxiety provoking, and concerning to everyone. So, what can we do about it? First, please bring this to the attention of your physician and neurology team. Social embarrassment and lack of understanding that this could be related to PD is the main reason this is often not brought to the attention of providers. In 2010, the American Academy of Neurology put out guidelines on quality measures in Parkinson’s disease. They recommended annual evaluations for everyone with Parkinson’s disease which included assessing for psychiatric disorders and disturbances such as psychosis, depression, anxiety, apathy and impulse control disorders. A proper assessment for psychosis includes:

1. Assessing for any triggers such as dehydration or underlying urinary & pulmonary infections

2. Review of sleep habits and patterns as poor sleep can provoke psychosis

3. Reviewing ALL prescribed medications that may contribute to psychosis

4. Reassuring and educating the individual and family

5. Reviewing the need for blood work or imaging looking for reversible causes of dementia

6. Reviewing the need for a full battery of neurocognitive testing

7. Considering REDUCING or ADJUSTING dopaminergic medications

8. Considering adding dopamine blocking medications, especially at night, such as Quetiapine

9. Considering adding medications such as Pimavanserin

For patients with troublesome hallucinations or delusions that continue despite some of the above

interventions, pharmacologic treatment directed at the psychotic symptoms may be necessary. If

antipsychotic medications are deemed necessary, preferred agents in patients with PD include

Quetiapine, Pimavanserin, and Clozapine. All antipsychotic drugs carry significant risks and a

thoughtful conversation with your physician is necessary in order to make an informed decision

before starting one of these medications. Among the antipsychotics, Quetiapine is the most

commonly used, and Clozapine may be the most effective but is rarely used due to its need for

frequent laboratory monitoring (necessary as it carries a risk of lowered white blood cell counts).

A newer medication, Pimavanserin, was approved by the U.S. Food and Drug Administration in 2016 for the treatment of Parkinson’s Disease Psychosis. Pimavanserin is unique in that it does not act via dopamine blockade (like other antipsychotics) and therefore carries less risk of worsening PD motoric symptoms. One drawback is that it takes about 4-6 weeks to begin working whereas the other antipsychotics have a more rapid onset.

As you can see, there are options if you are plagued by these symptoms. It all starts with an honest conversation. I am reminded of a line from a song from the band Coldplay called Clocks. “Am I part of the cure? Or am I part of the disease?”

Parkinson Path February 2021