Neurology India, Vol. 51, No. 3, July, 2003, pp. 359-360
A study of epilepsy-related psychosis
Roy AK, Rajesh SV, Iby N, Jose JM, Sarma GR
Code Number: ni03116
The association of epilepsy and psychosis is studied. Among the 500 patients of epilepsy evaluated, there were 12 patients, 8 males and 4 females with epilepsy-related psychosis. Their average age was 38 years. The interval between the age of onset of epilepsy and psychotic features was 9 years. Complex partial seizures were present in 7 patients and primary generalized tonic-clonic seizure was present in 1 patient. Four patients had post-ictal psychosis, 7 had acute interictal psychosis and 1 patient had chronic psychosis. The inter-ictal and chronic psychoses were schizophreniform whereas the post-ictal psychoses were not. EEG showed a temporal focus in 7 patients with complex partial seizures and an extra-temporal focus was identified in 4 out of the other 5 patients. Imaging (CT scan/MRI) revealed abnormalities in 10 patients. This study attempts to define the characteristics of psychoses occurring in epileptics.
Epilepsy is said to affect 20-40 million people worldwide. Mental health problems are increasingly being recognized as co-existing with or significantly complicating the management of patients with epilepsy. People who have epilepsy seem particularly liable to certain major psychiatric disorders. These disorders have been described under the broad rubric of Psychosis of Epilepsy., Jean Etienne Esquirol in his classical 1838 article has described acute states of excitation related to seizures. Levin described 52 cases of epileptic clouded states following two or more seizures. In their report of 14 cases, Logsdail and Toone identified the diagnostic criteria for post-ictal psychosis. Epidemiological studies have revealed an incidence of between 0.5% and 9% of psychoses in epilepsy. A recent Indian study reported a very low incidence of psychosis in cases with epilepsy. The aim of our study was to characterize the relationship between epilepsy and psychosis and to study the phenomenological aspects of psychosis related to epilepsy.
Five hundred consecutive patients of epilepsy were included in this study. The duration of the study was 3 years. The maximum follow-up was for 3 years. Patients of epilepsy were studied with regard to clinical features and response to treatment. EEG and imaging (CT/MRI scan) were done in all cases.
Patients with epilepsy, irrespective of its nature or etiology, having psychotic and other psychiatric symptoms were included in the study. The psychosis was in the form of depression, elation or anxiety-related symptoms. Patients having significant clouding of consciousness as in delirium and confusion were not included in the study. Patients having psychotic or psychiatric symptoms attributed to other medical or psychiatric causes (e.g. drug intoxication, metabolic disturbances, head injury, complex partial seizures) were also excluded. Patients having longstanding psychosis and subsequently developed seizures were excluded.
Of the 500 patients of epilepsy there were 261 (52%) males and 239 (48%) females. Their age ranged from 9-78 years with a mean age of 31 years. There were 12 patients (2.4%), 8 males and 4 females, with epilepsy-related psychosis. Their average age was 38 years. The interval between the age of onset of epilepsy and the onset of psychosis was 9 years. Complex partial seizure with or without secondary generalization was seen in 7 (58.3%) patients, simple partial seizure with secondary generalization was seen in 4 (33.3%) patients and primary generalized tonic-clonic seizure seen in 1 (8.4%) patient. EEG revealed a temporal focus in all 7 patients with complex partial seizures and an extra-temporal focus was seen in 3 of the other 5 patients. Imaging revealed abnormality in 10 (83.3%) out of 12 patients. Three patients had gliosis, 3 had calcified granuloma and 2 cases had medial temporal lobe sclerosis. Two patients had a suggestion of an ischemia/demyelination on MRI. Two patients without neuroimaging abnormalities had interictal psychosis.
Acute interictal psychosis was seen in 7(58.3%) patients, post-ictal psychosis was seen in 4 (33.3%) and chronic psychosis was seen in 1 (8.4%) patient. A schizophreniform phenomenology, i.e. positive symptoms like delusions of reference, auditory hallucinations, was seen in 8 (66.7%) patients. These 8 included all the acute interictal cases and 1 chronic case. Non-specific phenomenology was seen in 4 (33.3%) patients and these included all the post-ictal cases.
Despite their relatively common occurrence, post-ictal psychoses or other brief psychiatric symptoms occurring post-ictally have not been adequately studied., Umbricht et al studied 44 patients with refractory temporal lobe epilepsy and found 8 patients with post-ictal psychosis and 7 patients with chronic psychosis. In the present study, 4 patients (33.3%) had post-ictal psychosis and 1 patient had chronic psychosis.
Although some controversy surrounds the link between psychotic illness and epilepsy, the existence of an interictal psychotic disorder is now generally acepted. It is important to determine whether intermittent or belief psychoses are related to seizure activity. Some patients experience time-limited psychoses and do not experience the truly interictal psychosis, The more common interictal form is the persistent psychosis called schizophrenia-like psychosis of epilepsy (SLPE). These patients often lack the 'negative symptoms' seen in schizophrenia. Whether this syndrome is identical to or different from schizophrenia in the traditional psychiatric sense is undetermined.
In a comparison of symptoms, Perez and Trimble observed that 50% of patients with epilepsy and psychosis could be diagnosed as having schizophrenia. Such schizophreniform phenomenology was seen in 8 (66.6%) patients in this study, which included all interictal cases and 1 chronic case. Recent researchers have reported the enlargement of amygdala and significant reduction in total brain volume in patients with psychosis of epilepsy as compared to normal controls and TLE without psychoses. In the present series no such correlation was found.
Hermann et al suggested that psychosis is seen with greater frequency in patients whose epilepsy began from ages 13 to 18 years than in those with earlier or later onset. In a review of 14 cases by Trimble the mean interval was found to be 15 years (range 11 to 21 years). A temporal lobe focus appeared to raise the incidence of psychosis in epileptic patients, as did focal seizures with secondary generalization. The findings of focal seizures with secondary generalization and temporal lobe focus on EEG in our study are comparable to these findings.
This study has attempted to define the temporal characteristics of psychosis occurring with epilepsy into three well-defined categories namely post-ictal, acute interictal and chronic psychosis.
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