POSTICTAL AND CHRONIC PSYCHOSES IN PATIENTS WITH TEMPORAL-LOBE EPILEPSY

Objective: This study sought to elucidate the relation of clinical, ne uropsychological, and seizure variables to chronic and postictal psych oses in patients with temporal lobe epilepsy. Method: Forty-four patie nts with treatment-refractory temporal lobe epilepsy were given formal psychiatric evaluations; 29 patients had no psychiatric disorder or a nonpsychotic disorder, eight patients had postictal psychoses, and se ven patients had chronic psychoses. Comparisons of clinical, neuropsyc hological, magnetic resonance imaging, and seizure variables were made between the nonpsychotic and the psychotic patients and secondarily, between the patients with transient postictal psychoses and those with chronic psychoses. Results: Bitemporal seizure foci, clustering of se izures, and absence of febrile convulsions were associated with both p ostictal psychoses and chronic psychoses. Younger age at onset of epil epsy and lower verbal and full-scale IQs differentiated the patients w ith chronic psychoses from those with postictal psychoses. Conclusions : Patients with temporal lobe epilepsy with chronic and postictal psyc hoses show similar profiles of clinical and seizure variables, suggest ing shared etiologic factors. These factors may increase the propensit y to develop psychotic symptoms, while other factors, such as time of onset of epilepsy and underlying neuropathology, may determine whether transient or chronic psychotic symptoms develop. Even among patients with treatment-refractory temporal lobe epilepsy, a specific subgroup of patients, characterized by bitemporal seizure foci, art absence of febrile convulsions, and a history of clustering of seizures, appears to be particularly prone to develop psychotic disorders. A process sim ilar to secondary epileptogenesis may be involved in the development o f the psychoses.