According to the data of the WHO, epilepsy is the most frequent nervous disease. More than 50 million in the world suffer from this disease (2007). About 80 thousand of people (2007) suffer from epilepsy in the Republic of Belarus, it is about 0.81% of the Belarusian population.

Mental disorders represent an important component of the clinic of epilepsy that complicates its course. the investigation of the dynamics and structure of the incidence and prevalence of mental disorders in epilepsy has an important scientific and practical value which allows revealing shortcomings in rendering therapeutic and rehabilitative assistance to the contingent of epileptic patients with psychiatric disorders in the institutions of the psychiatric service.

It should be emphasized, there are no special researches, concerning general and primary disease incidence psychiatric disorders of patients with epilepsy in Belarus.

According to the 2010 data of Republic Mental Health Research Center, there were 506 patients with paroxysmal state in the epilepsy ward. Among them 438 cases were accompanied by psychiatric disorders.

Psychiatric disorder was diagnosed if there were symptoms during the interictal period. Cognitive disorders were diagnosed in 125 cases (28,5%), psychoses - in 3 cases (0.7%), depressive disorders - in 12 cases (2.7%), and personality disorders - in 298 cases (68%).

It is thought necessary to do special research on the basis of representative selections from the general population aimed at defining the role of epileptic activity which causes mental dysfunction and is involved in the pathogenesis of psychic disorders of epileptic patients.