Factors involved in the long-term prognosis of psychogenic nonepileptic seizures

Information on the long-term effects of psychogenic nonepileptic seizures (PNES) is limited. We therefore reassessed 22 patients 4-6 years after the initial diagnosis of PNES in a tertiary referral epilepsy center. The diagnosis was confirmed using clinical description and additional electroencephalogram investigations in 1998, 1999, and 2000. Patients with epilepsy and PNES as comorbid symptoms were not included. Reassessments were aimed at seizure reduction and possible psychogenic factors.

Three psychological tests were used at baseline at the time of diagnosis and repeated at end point. These three tests assessed different "levels" of psychological function [i.e., complaints (The Symptoms Check List Revised), coping strategy (The Dissociation Questionnaire), and personality factors/psychopathology Nederlandse Verkorte MMPI].

Twenty-two patients were included. Seizure frequency showed statistically significant reduction. At the time of diagnosis, none of the patients was seizure-free or had only yearly seizures, whereas at end point, 7 of 22 patients were completely in remission and 3 patients had only occasional seizures. The number of patients with daily seizures dropped from nine to two. It has not been fully clarified which factors caused this improvement, but the common denominators are that a definitive expert diagnosis in a tertiary center was made and all possible efforts were made to inform the patient in a respectful manner about the diagnosis. In addition to seizure reduction, there was improvement on different levels of psychological function, showing reduction in psychological distress, reduction in dissociative features such as amnesia, increase in self-control, reduction in feelings of dissatisfaction and passive avoidant behavior, and a more active attitude towards social contact.

In the long term, the patients with PNES who were included in our study have more self-control and approach social contact with a more self-confident attitude. This does not necessary reflect a causal relationship with the observed seizure reduction. Nonetheless, it is noteworthy that, post aut propter, the eradication of a symptom (i.e., seizures) with social consequences is followed by or is associated with a more confident social attitude. This opens possibilities for treatment strategies.