Identifying Cognitive Symptoms in Late-Life Psychosis

(Part 1 of 2)

In this video, Vimal Aga, MD, Embedded Geriatric Psychiatrist, Department of Neurology, Oregon Health and Science University, Portland, Oregon, discusses his recent presentation at recent presentation at the American Psychiatric Association (APA) Annual Meeting “Psychosis in Dementia or Dementia in Psychosis? A Clinical Approach to Late-Life Psychosis and Cognitive Decline.”

Dr. Aga describes cutting-edge clinical research about the underlying pathophysiology of late-life psychotic disorders.

In the upcoming Part 2, Dr. Vimal discusses a real-life example of a prior patient and the lessons he learned that can be applied to clinical practice as well as common misconceptions on this topic.

Dr. Vimal Aga: I'm Dr. Vimal Aga. I'm a geriatric psychiatrist by training. I work in the dementia program at the Oregon Health and Science University as an embedded geriatric psychiatrist in the Department of Neurology there. I'm also a psychiatric hospitalist in the med psych program at the Oregon State Hospital in Salem.

Q:  What were the main takeaways from your APA session?

A:  The main takeaways from my talk at the APA annual meeting, which was "Psychosis and Dementia or Dementia and Psychosis," are as follows.

As we all know, DSM-5 and previous editions of DSM are fairly agnostic regarding the underlying pathophysiology of psychiatric disorders, but there is now cutting-edge clinical research that has started to identify the underlying pathophysiology of late-life psychotic disorders.

A lot of it appears to be dementia, either prodromal presentations of dementia or dementia itself. Which is really interesting, because we've known for a long time that older adults with schizophrenia start to get cognitive impairment.

Now, at least some of it appears to be actual Alzheimer's disease or vascular dementia. It's really critical that practicing clinicians become familiar with identifying cognitive symptoms in late-life psychosis, and also psychotic symptoms in patients with dementia in order to make an accurate diagnosis.

You need to keep in mind that the older adult population in the country is literally exploding, so it doesn't matter what kind of a practice you have. Everybody will end up seeing older adults in their practice, whether you have a geriatric psychiatry practice or not, unless you happen to be working exclusively in child psychiatry.

Q:  What are the primary challenges for clinicians working with patients with neurocognitive disorders?

A:  The primary challenges for clinicians working with the neurocognitive disorders or the dementias are several. First, there is a lack of understanding of this vast topic, unless the clinician happens to have a geriatric psychiatry background, because didactic instruction really has not been able to keep up with the pace of current research in the neurocognitive disorders.

New constructs are coming up all the time, such as mild behavior impairment or new disorders such as LATE, which is limbic-predominant age-related TDP43 encephalopathy -- I know that's a mouthful -- or PART, which is primary age-related tauopathy.

These are being introduced, and people have to keep up with this new information. There is a whole new NIAAA research framework published recently in 2018, which really has completely changed how we view Alzheimer's disease dementia, even though it's meant for research, but clinicians do need to be aware of it.

Second, clinicians are often not given the tools to have a successful dementia practice. Diagnosing the type of dementia accurately requires knowledge of not just psychiatry, but also some knowledge about neurology, specifically the movement disorders, neuropsychology, neuroimaging, and CSF biomarker analysis.

None of which are covered in any great detail in the typical psychiatric curriculum. Third, even with the clinician is knowledgeable about these, they may not get the necessary support from their colleagues in hospitals.

Most hospitals outside of tertiary care academic centers do not have an MRI dementia protocol, and even some academic centers don't have that, interestingly. Most hospitals still do not have the expertise in interpreting FDG PET scans of the brain for dementia patients.

The vast majority of hospitals in the US are still not doing any molecular imaging, by which I mean amyloid PET and tau PET. Yet the use of these modalities may be critical in making an accurate diagnosis in select cases.

Fourthly, there is the problem of insurance coverage, because some of these tests are not covered by insurance, which means that they cannot be done outside of research studies, since they are very expensive if you have to pay for them out of pocket.

Just as an example, amyloid and tau PET are not approved for clinical practice. They will not be covered if you ordered these tests in your clinic. FDG PET, which has been around a long time, is still only approved for a single indication in clinical practice, which is differentiating Alzheimer's disease dementia from FDD.

It can be very useful in diagnosing other kinds of dementias as well. There are also more recent findings in structural brain scans, such as an MRI. For example, the swallow tail sign in 3D MRIs that is seen in DIP patients.

These can be missed if the correct sequence is not ordered and/or if the radiologist is not familiar with these signs. Again, it's really imperative that the clinician become knowledgeable about how and what to order in terms of diagnostic testing, are taking into account the insurance coverage issue as well.

Then also, to have the training and the knowledge to be able to interpret these studies themselves. I just want to add at the end that insurance coverage is especially problematic for young onset dementia patients, because these patients often have private insurance, which can often refuse to cover even the most basic of dementia workups.

Vimal Aga, MD is a board-certified Embedded Geriatric Psychiatrist in the Department of Neurology at Oregon Health and Science University, Portland, Oregon. Additionally, he is a psychiatric hospitalist in the Geriatric Psychiatry Program at Oregon State Hospital, Salem, Oregon.