In the Clinic With Marwan Sabbagh, MD

Dr. Sabbagh provides insights into supporting people with dementia-related hallucinations and delusions and their family members and caregivers.

For optimal viewing quality, please expand video to full screen.

Hello. I’m Dr. Marwan Sabbagh, Director of the Cleveland Clinic Lou Ruvo Center for Brain Health in Las Vegas, Nevada. I’d like to take a few moments to talk to you about dementia-related psychosis and the impact and consequences it has on people with dementia and their caregivers.

Dementia is common in older adults in the United States, with approximately 7.9 million people living with dementia. Neuropsychiatric symptoms are a common feature across the dementias, and their onset can occur at various times in the course of illness. Among neuropsychiatric symptoms, delusions and hallucinations are prevalent across the dementias. Although the prevalence rates of delusions and hallucinations vary based on dementia type, approximately 2.4 million people in the US have dementia-related psychosis.

I have dedicated 25 years to helping people with dementia and their family members and caregivers. I have seen hundreds of patients with neuropsychiatric symptoms, and it’s truly striking how significant these symptoms are in the context of the disease.

What exactly are delusions and hallucinations, and how are they differentiated from each other? A delusion is a false, fixed belief despite evidence to the contrary. For example, a patient may think that a family member is stealing from him or her or that the police are following him or her. A hallucination is a perception-like experience that occurs without an external stimulus and is sensory in nature. Patients may see, hear, smell, taste, or feel something that is not there.

It’s important to know that these are not fleeting symptoms; they are episodic and may persist. Older adults with delusions and hallucinations in dementia may experience these symptoms as often as 2 to 6 times per week. Some studies have shown that delusions persisted beyond 3 months in up to 82% of patients, and hallucinations persisted in up to 52% of patients.

I’d like to provide an example of how dementia-related psychosis can impact an older adult with dementia and his family or caregivers.

Earlier this year, I stopped into my clinic to see a patient. My staff had performed a MoCA—Montreal Cognitive Assessment—for dementia. The score was 12 out of 30; this man had advanced Alzheimer’s dementia. He had been experiencing a persistent delusion: He believed that his daughter was, in fact, his girlfriend. Understandably, this had been very difficult for his daughter who also served as one of his caregivers. To complicate matters further, this man lived alone and he often wandered away. The local police were constantly picking him up and bringing him home after he had wandered off.

The patient’s family was in distress, so they had him admitted to the hospital. However, he was discharged and returned home shortly thereafter. The family felt hopeless and was unable to manage him, so they brought him to my clinic. After the assessment, I dropped everything for an immediate intervention to help him and his family. With the help of a social worker, he was placed in a long-term care facility that day.

Now I’d like to address something that I’m commonly asked: Why do these symptoms of psychosis occur in adults with dementia?

The truth is, the neurobiology of psychosis is complex and unknown. Though other factors may play a role, 3 interconnected neurotransmitter systems are thought to be primarily involved: dopamine, glutamate, and serotonin.

In addition, certain brain changes have been associated with symptoms of psychosis in dementia. Examples include increased density of neocortical neurofibrillary tangles and decreased grey matter in the right frontal cortex.

Furthermore, structural and functional neuroimaging implicates frontotemporal regions in delusions and hallucinations across the dementias.

While we may not completely understand why our patients are experiencing these distressing symptoms, we know that dementia-related psychosis is disruptive and can be dangerous for patients and caregivers. I want clinicians of different specialties to be able to recognize the signs and symptoms of dementia-related psychosis early on. It is important to identify delusions and hallucinations, because about 2.4 million dementia sufferers in the United States experience these symptoms. I want clinicians to truly proceed with caution when it comes to treatment. Currently, there aren’t any FDA-approved drugs for dementia-related psychosis, though clearly there is a need.

For me personally, I’m studying drivers of morbidity and mortality and predictors of disease progression. I’m also looking at factors that drive placement of patients in long-term care facilities and other factors that contribute to caregiver distress. Through it all, I’m dedicated to improving the quality of life for people with dementia-related psychosis and their caregivers.

Thank you for watching. I hope my insights from the clinic help you better understand the prevalence and impact of delusions and hallucinations in dementia-related psychosis.


Cleveland Clinic Lou Ruvo Center for Brain Health
Las Vegas, NV

Faculty Insights

Appropriate care requires that treatable phenomena be sought and managed; this includes dementia-related psychosis.

–Jeffrey Cummings, MD, ScD