“Dr. Gilbert Hosts: Cognition & Parkinson’s Disease” – Webinar Notes

“Dr. Gilbert Hosts: Cognition & Parkinson’s Disease” – Webinar Notes

“Dr. Gilbert Hosts: Cognition & Parkinson’s Disease” featured guest speaker Kathleen Poston on the topic of cognition and dementia in Parkinson’s disease. It was part of the “Dr. Gilbert Hosts” series hosted by Dr. Rebecca Gilbert, the chief scientific officer at the American Parkinson Disease Association (APDA). 

Cognitive issues are non-motor symptoms of PD and can start at the beginning of the illness. It is important to test people’s cognition as early as possible, because having that test result is the most effective baseline. Dr. Poston also detailed possible treatment options, both medication-related and non-medication strategies.

For more information on cognition and PD, see the Stanford Parkinson’s Community Outreach page.

The webinar can be found on the APDA’s YouTube channel.

Please see below for notes on the February 17th webinar.


– Joëlle Kuehn

“Dr. Gilbert Hosts: Cognition & Parkinson’s Disease”

Speaker: Kathleen Poston, MD, movement disorder specialist, Stanford University

Webinar Host: American Parkinson Disease Association

Webinar Date: February 17, 2021 

Summary by Joëlle Kuehn, Stanford Parkinson’s Community Outreach

Cognition issues are non-motor symptoms of PD:

  • Executive function
    • One of the most common symptoms in PD
    • How you operate around your day to day activities
    • Multitasking, organizing, what needs to be done to do XYZ activity
    • Also, the ability to incorporate new information into your decision making
  • Visuospatial reasoning
    • One of the most common symptoms in PD
    • How you interpret world around you and incorporate the visual information into your decisions
    • Not just visual functioning, but visual decision making
      • Ex. parking a car correctly, walk into a room and see a chair you want to sit into (take right amount of steps, turn at the right time, sit down at the right time)
  • Attention and working memory
    • Attention is how well you can focus on the thing you are doing and ignore the things that aren’t important
    • Working memory: ability to keep information in your head just long enough so that you can use it and then it’s gone
  • Memory
    • Ability to remember conversations the day before, breakfast, remember that you have appointments without looking at reminders
  • Language 
    • Least common in PD
    • Ability to name objects when you see them

Do cognitive tests to test cognitive function. It is common to test motor symptoms of PD, and cognitive tests are more difficult. Use screening tests that are comprehensive neuropsychological evaluation.

PD and early cognitive changes:

  • As we get older, everyone experiences some level of cognitive decline with normal healthy aging (ex. word finding difficulty)
  • There is a certain level of cognitive decline that is above what is expected for normal aging, this is called mild cognitive decline and is not normal
  • Mild cognitive impairment – cognitive deficits that do not impair one’s ability to carry out activities of daily living
    • Cognitive changes may start at the very beginning of the illness.  Some people have no cognitive changes at the beginning, but others do and it can be an indicator of disease at the time of diagnosis
    • Problems with multi-tasking/shifting paradigms
    • Trouble with planning and organizing, but can still manage

PD and Dementia:

  • Dementia – cognitive deficits in more than one cognitive domain which significantly impair everyday functioning
    • Can’t go to the store and follow a list, can’t follow a recipe
    • It is the impact on day to day life that is the important differentiator
  • Likely caused by presence of Lewy bodies in brain regions involved in cognition
  • Prevalence increases with time from diagnosis
  • Characterized by executive dysfunction and visuospatial deficits
  • As disease progresses, language, and memory can be involved as well
  • Risk factors for dementia: apathy, visual hallucinations
  • In older populations, alzheimer pathology can be present in the brain as well
    • Sometimes it is more than one thing causing dementia
    • That risk gets higher the older you are
  • May also be behavior problems such as anger, aggression, irritability, mania, impulse control disorders, and personality changes

PD and Dementia: what do we do about it? – minimizing concurrent issues

  • Making sure there isn’t anything that could be making it worse
    • Not cause it, but worsen it
  • Assess all medications (including medications prescribed for PD), and their side effect profiles
    • Some can worsen cognitive effects
    • Balance between helping motor symptoms and worsening cognitive symptoms
    • Non-PD such as pain medications (esp. Sedating or sleeping) or bladder dysfunction can be bad 
  • Check for intercurrent infection
    • If cognition gets worse over days or hours it can be infection 
    • Urinary tract infections are common in this
  • Measure thyroid function, Vitamin B12 levels
  • Evaluate for depression
  • Treat dehydration and orthostatic hypotension
  • Consider obstructive sleep apnea
  • Correct hearing loss
  • Correct visual loss – after correct prescription or cataracts removed- visuospatial can increase

Treatment: – Medications:

  • Don’t have a medication that is specifically formulated for cognitive problems in PD
  • Cholinesterase inhibitors that inhibit acetyl-choline can work
  • One of the medications for Alzheimer’s works well with PD:  Rivastigmine.  Trade name: Exelon – patch or pill
  • Less robust data for use of other cholinesterase inhibitors (donepezil, galantamine)
  • NMDA receptor antagonists such as memantine show mixed results.  Data not as strong but is a reasonable one to consider

Treatment: Non-medication strategies:

  • Simplify activities into small manageable steps and maintain a regular routine
  • Keep clutter to a minimum
  • Remain mentally, socially and physically engaged
  • Join a person with PD and/or care partner support group to both get and share ideas with others

There are other medications on the horizon.

Question & Answer:

Question: What is the difference between Lewy Body Dementia and PD? 

Answer: The difference is dependent on which came first – motor or cognition. If someone’s changes in neurological system start off with motor symptoms, and those motor symptoms persist for at least a year before they have substantial memory problems like dementia – Parkinson’s disease. If someone symptoms start with dementia or start within the first year of their motor symptoms, we call that Lewy body dementia. 

Question: Are there mental or physical exercises that can slow cognitive decline?

Answer: research studies have not proven without a doubt that mental or physical activities clearly slow the development of cognition, but there is some data to suggest that it is helpful. Physical activity has consistently been shown to boost cognition in people with PD, so it can improve cognition but unknown if it can help slow deterioration. Regarding mental activities, that data is conflicting. Broadly speaking, staying cognitively engaged is good for boosting cognition, but don’t know if it slows cognitive deterioration. The problem with brain games is if you do it a lot you get really good at the brain game but it doesn’t really translate particularly well to being able to do other things better. If you enjoy doing them, I encourage you too.

Question: Any medications or supplements that slow down the progression of cognitive issues?

Answer: As of right now there is no medication to slow it down, and none to prevent the development of dementia. All medications we have are simply symptomatic (to treat symptoms). There has not been any data to support supplements to prevent or slow it down. Most of the supplements don’t get into the brain at all, it is hard to get medications into the brain. I would be leery of any kind of supplement that promises slowing down cognitive decline because it isn’t proven and probably not true.

Question: Relationship with Deep Brain Stimulation (DBS) and cognition? Can it help?

Answer: Right now the FDA-approved targets we have for DBS, thalamus, subthalamic nucleus and globus pallidus do not help cognitive impairment. There are studies for others but they are not proven. However, there are some people, not all, who DBS could hurt their cognition. Doing a thorough and proper pre-DBS evaluation is critical because it is important to find if people can be harmed by DBS. Those people are people who have already shown significant drops on formal neuropsychological tests prior to surgery, so they’ve already shown that their cognition has deteriorated enough that DBS will actually make it worse. If someone performs cognitively within the range expected for their age on cognitive tests, the data has not shown that it is detrimental for cognition. 

Question: Can you address young onset PD and cognition? Are there differences to consider?

Answer: there is a difference between age and disease duration. For people in their 70’s and 80’s, the duration of time it can take to have cognitive problems can be a lot shorter, whereas people who are younger with the diagnosis, it can take a lot longer. There could be some mild disexecutive functions, it’s good to be aware of, but severe cognitive problems often don’t develop for many decades. There are always exceptions to these rules though.

Question: Can diet slow down cognitive decline?

Answer: Broadly speaking for PD, there is no specific diet identified to be the most beneficial for PD. One of the things we see at autopsies for people with PD is that they have vascular abnormalities or small strokes, and we have found that people who have PD and also have small strokes or larger strokes as they get older, their cognition is very specifically affected by combination of strokes and PD. I would recommend any diet that your heart doctor recommends to prevent heart disease and stroke is probably the best one for you.  It helps prevent a double hit. Some data suggests the mediterranian diet to help with heart attack and strokes but it hasn’t been studied in people with PD who are at risk for also having strokes. 

Question: What guidance do you give your patients who are having cognitive issues?

Answer: First thing I tell patients is to understand the problem. Getting the sophisticated neuropsychological testing is a great starting point. Not everyone has all or the same cognitive symptoms, and understanding what the problem is for you as an individual, because then things can be changed in your day-to-day life.

Question: Should I be getting cognitive testing before I am having cognitive issues?

Answer: It is never a bad idea. We use age appropriate normative values but everyone is different and has a different baseline, so having a starting point to have your own baseline can help if things do change.

Question: Does COVID or the COVID vaccine have any effect on cognition in PD?

Answer: There’s a lot of research happening right now. What it appears is that COVID affects PD the same way any bad infection affects PD. With the flu and COVID, tremors, balance, cognition were worse, but people recovered and the symptoms improved after. With PD any kind of infection will make any part of PD worse. The brain is protected space so it doesn’t get infected. Regarding the vaccination, I am not seeing any negative effects of the vaccine in the patients who have the vaccine, although broadly speaking, the second dose is difficult for everyone.

Question: Any reason for hope or encouragement regarding the future of cognition and PD?

Answer: There is a very large focus and understanding right now (in PD community and biotech community, and NIH) that this is an unmet need and they are getting engaged where previously they wouldn’t. The awareness campaigns are making a difference and the funding agencies and funding agencies are listing. The 3 clinical trials going on right now is a huge win. 

Question: Relationship of hallucinations, cognition and PD?

Answer: Studies have shown the development of hallucinations and dementia in Lewy body diseases tend to happen around the same time, and tend to be associated with each other because they come from similar areas of the brain. Often patients have awareness that they are hallucinations and aren’t real. When it becomes more difficult to determine if it’s real or not and the patients no longer have the insight to differentiate, the hallucinations can become delusions. Hallucinations are treated similarly and together with dementia. Medications can worsen hallucinations, so it is important to check.

Question: Relationship of apathy and cognition?

Answer: Apathy also can start or worsen at the same time that cognition is worsening. It is a lack of interest or engagement in things they would previously be involved in. Treating apathy is difficult, sometimes antidepressant medications can help a bit. Often when patients increase interest and engagement, the cognitive impairment can improve.

Question: Can music help cognition?

Answer: Music and art in general are wonderful to engage the brain in ways that help you improve movement, mood, apathy, cognition and dementia. It’s a great way to engage people.