Does your loved one with Lewy body dementia accuse you of being an imposter? They may have Capgras syndrome—a disorder that is also known as Capgras delusions, delusional misidentification syndrome, and the “delusion of doubles.”
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Experts estimate that up to 17% of people withdementia with Lewy bodiesexperience Capgras syndrome.
Hallucinations and Capgras Syndrome
Research indicates that hallucinations in Lewy body dementia are highly correlated with the development of Capgras syndrome. One study also found that people who were being treated with cholinesterase inhibitors (which are sometimes used to treat hallucinations in Lewy body dementia) were less likely to develop Capgras syndrome.
Anxiety and Capgras Syndrome
Anxiety has also been identified as a significant risk factor, with one study finding that people with anxiety and dementia with Lewy bodies had 10 times the risk of developing Capgras syndrome.
Prevalence of Capgras Syndrome in Alzheimer’s
Research has concluded that some people with Alzheimer’s disease also develop Capgras syndrome, although some studies indicate they may also have some Lewy bodies in their brains.
Other Conditions Associated With Capgras Syndrome
Capgras syndrome has been described in other degenerative brain diseases, includingParkinson’s disease(which is very closely related to Lewy body dementia) andfrontotemporal dementia. It has also been found in people with schizophrenia, strokes, and drug abuse.
How to Respond
Caregivers of people with Capgras syndrome report increased challenges compared to caregivers of people with Lewy body dementia who do not display Capgras syndrome.
Because the cognitive function of people with Lewy body dementia varies greatly from time to time, responding to Capgras syndrome is difficult. Sometimes, just going with the flow of the conversation will work, but some caregivers report that the person with Lewy body dementia will catch them in verbal inconsistencies if, for example, they agree that they’re the imposter.
Additionally, since the person may believe the caregiver or family member is an imposter, verbal orphysical aggressionis possible, so caution is suggested in response to Capgras syndrome.
You may find that some of the same tips onresponding to hallucinations in Lewy body dementiawork well in Capgras syndrome since both hallucinations and Capgras syndrome are a misperception of reality.
Treatment
Treating Capgras syndrome requires a cautious approach if medications are going to be used. People with Lewy body dementia are more at risk for serious side effects fromantipsychotic medications, which are often prescribed forparanoia, delusions, and hallucinations. Be sure to report Capgras syndrome to your loved one’s physician for proper evaluation and treatment.
A Word From Verywell
Capgras syndrome presents an additional challenge for those experiencing Lewy body dementia, as well as their caregivers. Despite the frustrations that it creates, try to remember that Capgras syndrome can be very anxiety-producing for the person with dementia. Responding calmly and compassionately after taking a deep breath can help you both.
2 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Thaipisuttikul P, Lobach I, Zweig Y, et al.Capgras syndrome in dementia with Lewy bodies.Int Psychogeriatr. 2013;25(5):843-849.Förstl H, Besthorn C, Burns A, et al.Delusional misidentification in Alzheimer’s disease: a summary of clinical and biological aspects.Psychopathology. 1994;27(3-5):194-9. doi: 10.1159/000284869.
2 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Thaipisuttikul P, Lobach I, Zweig Y, et al.Capgras syndrome in dementia with Lewy bodies.Int Psychogeriatr. 2013;25(5):843-849.Förstl H, Besthorn C, Burns A, et al.Delusional misidentification in Alzheimer’s disease: a summary of clinical and biological aspects.Psychopathology. 1994;27(3-5):194-9. doi: 10.1159/000284869.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Thaipisuttikul P, Lobach I, Zweig Y, et al.Capgras syndrome in dementia with Lewy bodies.Int Psychogeriatr. 2013;25(5):843-849.Förstl H, Besthorn C, Burns A, et al.Delusional misidentification in Alzheimer’s disease: a summary of clinical and biological aspects.Psychopathology. 1994;27(3-5):194-9. doi: 10.1159/000284869.
Thaipisuttikul P, Lobach I, Zweig Y, et al.Capgras syndrome in dementia with Lewy bodies.Int Psychogeriatr. 2013;25(5):843-849.
Förstl H, Besthorn C, Burns A, et al.Delusional misidentification in Alzheimer’s disease: a summary of clinical and biological aspects.Psychopathology. 1994;27(3-5):194-9. doi: 10.1159/000284869.
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