Capgras Syndrome

Etiology

Capgras syndrome is a complicated and organic condition caused by structural brain injuries with neuroanatomical damage.[8][9] The cerebral basis of the CS was first explained in 1979 by Alexander et al. as a disorder that correlated with a combination of the right hemisphere damage causing problems with visual recognition and frontal lobe damage-causing difficulties with familiarity.[10] Another study found possible correlations between CS and prosopagnosia in brain-injured patients. Prosopagnosia is a condition in which patients cannot recognize faces.[11] 

Some psychologists hypothesized that patients with CS have conscious ability to recognize faces was still potent. Still, they may also present with damage to the system that facilitates emotional arousal to familiar faces.[12] It entails that an individual may recognize someone while feeling that something is 'wrong' about them. Hirstein and Ramachandran also shared similar findings in studying one patient with CS after a brain injury. This brain injury could be a disconnection between the temporal cortex, an area where familiar faces are recognized, and the limbic system involved in emotions.[13] Hirstein revised this theory and suggested that the patient with CS would not recognize familiar faces.[13]

CS can be seen with reduplicative paramnesia, a delusional misidentification syndrome in which a subject believes a location has been relocated. CS and reduplicative paramnesia are linked since they affect the same brain regions.[10] 

Epidemiology

A study on the prevalence of Capgras syndrome found that its existence in psychiatric populations is under 1%.[14] Another study found the prevalence of CS in all psychiatric conditions to be 1.3% to 4.1% and around 3% for hospitalized patients with psychosis.[15][16] A longitudinal study of patients hospitalized for a primary psychotic episode found that CS is seen in about one in every ten patients.[14] The prevalence of CS was highest among patients with schizophreniform psychosis (50%), brief psychosis (34.8%), and unspecified psychosis (23.9%).[17] About 15% of major depressive episodes and 11% of the patients with delusional disorders and schizophrenia displayed CS symptoms.[17]

The most common underlying primary psychiatric diagnoses in CS are schizoaffective disorder, schizophrenia, and bipolar affective disorder.[17] In a review of over 4,000 patients, six cases had symptoms of CS. Most CS patients displayed violent behavior towards a familiar person and had neuro-medical comorbid conditions.[5] In another review of 260 case reports of delusional misidentification syndromes, 174 (66.9%) patients had CS. CS cases had a high rate of other psychiatric conditions schizophrenia (73% of CS cases), dementia (26.4% of CS cases), and mood disorders (16.7% of CS cases).[5] It has been reported in association with organic disorders in about 25% to 40% of CS cases.[5]

Pathophysiology

The pathophysiology of Capgras syndrome lacks clarity due to its rare nature. Coltheart et al. described a dual factorial hypothesis of the delusional belief validated by the brain's imaging studies. The first prevents familiar faces from inducing an emotional response, while the second controls the ability to reject the delusional belief.[18] There is a disconnection in the pathway between the temporal lobe, the area that coordinates facial processing, and the limbic circuits associated with the appropriate personal and emotional stimulus.[18] 

Undesirable effects from the right hemisphere and frontal lobe dysfunction result in low self-monitoring, ego boundaries, and familiarity with stimuli. Lesions on the bifrontal or right hemisphere cause a disconnection between the frontal lobes and the right temporal-limbic lobes or system, essential for the reconciliation of information about the self-identification of the subject.[19] 

Psychodynamics of Capgras Syndrome

In a review of the first five case reports of CS, Capgras noted that each case was distinct, and no single pattern emerged. The study revealed that the doubles were always of people tied to the patient with strong affective ties.[2]

In their early studies in the 1920s, Capgras and Carrette discussed oedipal problems in women. They stated that this syndrome does not occur in men and that it was peculiar in women. Capgras also found feelings of strangeness in a few cases. Mechanisms suggested by many hypotheses by Capgras showed that a patient becomes aware of changes in their responses to significant persons in their lives. These dynamic changes may occur as a result of genuine changes in the other person.[2]

Berson stated that psychodynamic explanations cluster around four primary themes that emphasize oedipal problems, feelings of strangeness, problems with ambivalence, and pathological splitting of internalized object representations.[2] Berson suggested an interaction of three factors, the psychotic regression to primitive thinking, a paranoid state, and indecisiveness. Another early study found that two primary opposing views of the same person are present, and this uncertainty creates the foundation of CS psychopathology.[2] It means that the doubles' invention allows the patient to act with hostility without risking the guilt that may later emerge. Also, the process of splitting internalized object representations is a facilitator for CS. In other words, CS involves the process of splitting an entity into good and bad images. This splitting becomes pathological because of distortions in interpersonal communications that give off maligned internalized object representations.[20] 

Violence in Capgras Syndrome

A previous study has shown associations between CS with aggression and homicide.[21] Homicide was reported in 6% of the functional cases, which might indicate the delusion is riskier than first believed.[22] Despite finding associations between aggression and functionality (38%) rather than organic etiology, it was also frequent in the latter (23%). Pandis also suggested, however, that the non-violent Capgras patients constitute the majority. In a review of 4,200 patients in 1983, most cases were determined to have threatened or shown violent behaviors towards a familiar person. Many also had neuro-medical conditions present as confounding contributors.[5] The violence occurs due to psychological regression.[6]

History and Physical

Capgras syndrome patients may present with a variety of symptoms, depending upon the underlying disorder. Irrespective of the etiology that consists of schizophrenia and schizoaffective disorders, Alzheimer disease (AD), dementia, Lewy body dementia, epilepsy, cerebrovascular accident (CVA), pituitary tumors, and advanced Parkinson disease (PD), the CS experience delusion of identical doubles that is close to them.[1][4][5] The patient may also be agitated and aggressive towards the person significant to them due to a defect in recognizing familiar faces.[8][13]

Evaluation

Capgras syndrome is a clinical diagnosis. Its diagnosis is based on clinical assessment of symptoms.[5]

Treatment / Management

Treatment and Management of Capgras Syndrome

Generally, delusional disorders are challenging due to poor patient insight. Lack of empirical data poses a significant challenge to manage Capgras syndrome patients effectively.[23] Therapy, with the support of antipsychotic medications, is a common intervention.[23] Management of CS includes establishing a therapeutic alliance while negotiating mutually acceptable symptomatic treatment goals. It involves expressing empathy and interest in the patients' predicament.[22] It is also necessary to avoid confrontation of the Capgras symptoms.[6] Another study has also shown that using medications appropriately to target the underlying disorder's core symptoms is an effective management strategy.[15] Patient hospitalization is necessary if the patient is engaging in self-harm or violence. Identifying and treating comorbid psychiatric disorders is key to the management of CS.[15][24](B3)

Counseling Patient and Family Education

Due to the risk of violence meted on the misidentified person, it is crucial to assist CS patients' caregivers by utilizing communication techniques, counseling, medications, and reasonable problem-solving skills. Caregivers' feelings must be taken into consideration to reassure them. Better auditory interaction is advocated. Such communication is aimed primarily to circumvent CS patient's difficulty connecting with caregivers through face-to-face encounters. The caregiver needs to announce themselves and communicate clearly while out of sight to establish better emotional ties. The caregiver should self-evaluate to recognize gaps and strengths in managing the patients' condition while also relying on other family, friends, and relatives.[24](B3)

Prognosis and Complications of Capgras Syndrome

The onset of the Capgras syndrome can occur concurrently or later than the initiation of the comorbid psychosis. A study following 20 CS patients found the resolution of Capgras Syndrome symptoms after remission of the depressive disorder. The CS symptoms were more persistent in the schizophrenia patients that present with psychosis. If the onset of CS coincides with psychosis, the reappearance of the psychotic condition may return the CS symptoms.[25]

CS symptoms may result in intrapersonal and interpersonal conflicts, along with poor social relationships. An individual with this kind of disorder is prone to self-harm and violence. There are also implications for the patient's family, as the stress on the caregiver and stigma-related stressors could further compound the issue.[24] Socioeconomic implications include the patient's inability to retain a job, which further impacts household members, including caregivers. In a nutshell, the Capgras Syndrome poses a strain on the health care system and society.(B3)

Differential Diagnosis

Differential Diagnosis

Capgras syndrome and delusional disorders generally may co-exist with other illnesses. Table 1 below shows the various medical conditions associated with the development of delusional disorders.[1][4][26] 

There are fluctuating levels of consciousness, hallucinations, and poor cognitive abilities in delirium cases that are not present in cases of delusional disorders.[2] In substance-related disorder cases, drugs like amphetamines and cocaine are associated with delusions. Hallucinogens, alcohol, and steroids are linked with delusional disorders.[2] In cases of schizophrenia, the delusions are usually bizarre with associated hallucinations.[4]

Prognosis

The onset of the Capgras syndrome can occur concurrently or later than the initiation of the comorbid psychosis.[25] A study following 20 CS patients found the resolution of Capgras syndrome symptoms after remission of the depressive disorder. The CS symptoms were more persistent in the schizophrenia patients that present with psychosis.[25] If the onset of CS coincides with psychosis, the reappearance of the psychotic condition may return the CS symptoms.[25]

Complications

Capgras syndrome symptoms may result in intrapersonal and interpersonal conflicts, along with poor social relationships. An individual with this kind of disorder is prone to self-harm and violence. There are also implications for the patient's family, as the stress on the caregiver and stigma-related stressors could further compound the issue.[24] Socioeconomic implications include the patient's inability to retain a job, which further impacts household members, including caregivers. In a nutshell, the Capgras Syndrome poses a strain on the health care system and society.[24][25]