Epidemiology and Pathophysiology of Dementia-Related Psychosis

Learn which symptoms of psychosis are common in different types of dementia and how to compassionately discuss them with patients and their care partners. 


Along with cognitive decline, 90% of patients with dementia experience behavioral and psychological symptoms, such as psychosis, aggression, agitation, and depression. Dementia-related psychosis (DRP), which includes delusions and hallucinations, contributes to institutionalization, cognitive decline, and caregiver burden. Delusions and hallucinations tend to increase with the duration and severity of the disease, but there are also individual fluctuations. While a variety of symptoms can occur in all types of dementia, visual hallucinations are particularly common in the Lewy body dementias (dementia with Lewy bodies and Parkinson disease dementia). Mechanisms behind DRP are multifactorial, including different neurobiological factors as well as environmental, social, and psychological factors. This report examines the frequency, symptoms, and pathophysiology of DRP and communication about psychotic symptoms with patients with dementia (if possible) and their care partners.

From the Series: Dementia-Related Psychosis: Recognition and Treatment

To cite: Aarsland D. Epidemiology and pathophysiology of dementia-related psychosis. J Clin Psychiatry. 2020;81(5):AD19038BR1C.

To share: https://doi.org/10.4088/JCP.AD19038BR1C

© Copyright 2020 Physicians Postgraduate Press, Inc.

Target Audience

  • Neurologists
  • Psychiatrists
  • Nurse practitioners
  • Physician assistants

Learning Objectives

Talk with patients with dementia (if possible) and their caregivers about psychotic symptoms

Activity summary
Available credit: 
  • 0.50 AMA PRA Category 1 Credit™
  • 0.50 Participation
Activity opens: 
Activity expires: 

Support Statement

Supported by an educational grant from ACADIA Pharmaceuticals Inc.

Learning Objective

After completing this educational activity, you should be able to:

  • Talk with patients with dementia (if possible) and their caregivers about psychotic symptoms

Release, Review, and Expiration Dates

This brief report activity was published in September 2020 and is eligible for AMA PRA Category 1 Credit™ through September 30, 2022. The latest review of this material was August 2020.

Statement of Need and Purpose

Hallucinations and delusions are key behaviors contributing to behavioral crises in patients with dementia, and a lack of consistency in assessment of behaviors has been found. Clinicians may lack awareness of the incidence of psychotic symptoms in different forms of dementia, as dementia pathology has been incorrectly diagnosed on the basis of the presence or absence of psychosis. Some patients may not be able to describe their psychotic symptoms, requiring caregiver input to aid clinicians in recognition. Rating scales can be implemented to aid identification. Clinicians need education about assessing patients with dementia for hallucinations and delusions and about the incidence of psychotic symptoms in different forms of dementia. In addition, many patients with dementia-related psychosis (DRP) receive antipsychotics and are on treatment for over a year, although guidelines recommend tapering after 4 months. Clinicians need education to implement guideline-concordant care that is tailored to the individual patient, incorporating current information on the risks and benefits of nonpharmacologic and pharmacologic interventions for DRP. This activity was designed to meet the needs of participants in CME activities provided by the CME Institute of Physicians Postgraduate Press, Inc., who have requested information on DRP.

Disclosure of Off-Label Usage

Dr Aarsland has determined that, to the best of his knowledge, no investigational information about pharmaceutical agents or device therapies that is outside US Food and Drug Administration–approved labeling has been presented in this activity.

Review Process

The faculty member agreed to provide a balanced and evidence-based presentation and discussed the topic and CME objective during the planning sessions. The faculty’s submitted content was validated by CME Institute staff, and the activity was evaluated for accuracy, use of evidence, and fair balance by the Chair and a peer reviewer who is without conflict of interest.


This activity is derived from the teleconference series “Dementia-Related Psychosis: Recognition and Treatment,” which was held in May and June 2020 and supported by an educational grant from ACADIA Pharmaceuticals Inc. The opinions expressed herein are those of the faculty and do not necessarily reflect the opinions of the CME provider and publisher or the commercial supporter.

Faculty Affiliation

Dag Aarsland, MD, PhD
National Institute for Health Research (NIHR) Biomedical Research Centre (BRC) at South London and Maudsley NHS Foundation and Institute of Psychiatry, Psychology & Neuroscience at King's College London, UK

Financial Disclosure

The faculty for this CME activity and the CME Institute staff were asked to complete a statement regarding all relevant personal and financial relationships between themselves or their spouse/partner and any commercial interest. The CME Institute has resolved any conflicts of interest that were identified. No member of the CME Institute staff reported any relevant personal financial relationships. Faculty financial disclosures are as follows:

Dr Aarsland has received research support and/or honoraria from AstraZeneca, Lundbeck, Novartis, Biogen, and GE Health and served as a paid consultant for Lundbeck, Eisai, Heptares, and Mentis Cura.

The Chair for this activity, Clive Ballard, MBChB, MMedSci, MRCPsych, MD, is a consultant for and has received honoraria from Acadia, Roche, Lundbeck, Exevia, AARP, Synexus, and Novo Nordisk; has received grant/research support from Synexus, Novo Nordisk; and is a member of the speakers/advisory boards for Acadia, Roche, AARP, Synexus, and Novo Nordisk.

Accreditation Statement

The CME Institute of Physicians Postgraduate Press, Inc., is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

Credit Designation

The CME Institute of Physicians Postgraduate Press, Inc., designates this enduring material for a maximum of 0.50 AMA PRA Category 1 Credit™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Note: The American Nurses Credentialing Center (ANCC) and the American Academy of Physician Assistants (AAPA) accept certificates of participation for educational activities certified for AMA PRA Category 1 Credit™ from organizations accredited by the ACCME.

To obtain credit for this activity, study the material and complete the CME Posttest and Evaluation.

MOC Approval Statement

Through the American Board of Medical Specialties (“ABMS”) ongoing commitment to increase access to practice relevant Continuing Certification Activities through the ABMS Continuing Certification DirectoryEpidemiology and Pathophysiology of Dementia-Related Psychosis has met the requirements as a MOC Part II CME Activity (apply toward general CME requirement) for the following ABMS Member Boards:

MOC Part II CME Activity

Psychiatry and Neurology

Available Credit

  • 0.50 AMA PRA Category 1 Credit™
  • 0.50 Participation


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