Capgras Syndrome and Vascular Dementia

A 76-year-old man was examined as an outpatient. He was prompted by his family to visit a psychiatrist, and he was accompanied by his wife who was horrified and distressed. Twenty days before referral, he had developed the delusion that his wife had been replaced by another lady with quite similar external features. He displayed aggressive behavior toward the supposed impostor. On examination, the patient’s thought and speech processing were impaired, and his score in the Mini-Mental State Examination was 23/30. He had no past psychiatric history, but his medical history revealed inadequately controlled hypertension. The patient was referred for laboratory investigation, including neuroimaging. The brain CT revealed several infarctions in the white matter. The patient was diagnosed with early-stage vascular dementia. He was prescribed risperidone and donepezil, which resulted in the improvement of his symptomatology. The patient was also referred to physicians for the management of hypertension.

Although misidentification syndromes are not uncommon in patients with vascular dementia, especially in the later stages of the disorder, 3 there are only two reported cases of patients with Capgras syndrome associated with vascular dementia and vascular cognitive impairment. 4, 5 This unusual presentation of Capgras syndrome as a first symptom in vascular dementia, together with a previous report of a patient whose syndrome developed in the early stages of vascular dementia, 4 suggests that the development of the syndrome in cases of vascular dementia may differ in terms of time of appearance from cases associated with other conditions. It should be noted that although misidentification syndromes typically appear in later stages of the disease, they can also occur early in patients with Alzheimer’s disease. 2

Capgras syndrome and other delusional misidentification syndromes may develop early in the course of vascular dementia and may contribute to the patient’s morbidity. They may be associated with aggressive behavior, thus causing significant distress to caregivers and may worsen functioning in a patient with physical (i.e., vascular) morbidity. Clinicians should consider vascular dementia as an underlying cause of Capgras syndrome and arrange appropriate clinical and laboratory investigation. Particular attention should be paid in the evaluation of aggression and the risk of violence. 4 Treatment with antipsychotics and/or acetylcholinesterase inhibitors may help patients.