P 241. Effects of vagus nerve stimulation on self-concept and locus of control in epilepsy patients

Abstract

Background In the treatment of epilepsy, vagus nerve stimulation (VNS) has shown effects beyond seizure control in terms of improvements of mood, vigilance and attention. Here we investigated in possible effects of VNS on self-concept and locus of control. It was hypothesized that both continuous stimulation and the option of inducing ictal stimulation by use of a magnet can contribute to improved self-efficacy and internal feeling of control in patients following implantation of a vagus nerve stimulator. Methods In this pilot study, 11 consecutive adult epilepsy patients who were able to and agreed to fill out questionnaires prior to implantation of a VNS device as well as at least 6 months after implantation were analyzed. For assessment of self-concept and locus of control, the FKK (Fragebogen zu Kompetenz-und Kontrolluberzeugungen) was used. This questionnaire contains 32 questions assessing the concept of self, internal vs. external locus of control and self-efficacy. Results Patients showed significant improvements in terms of less expressed heteronomy and increased self-efficacy. Self-concept (confidence, self-efficacy, options for action) and internal locus of control showed similar improvements. Changes were not correlated to improvements in seizure control. Discussion These data suggest that vagus nerve stimulation for the treatment of epilepsy leads to improvements in self-concept and subjective locus of control which is independent of seizure control. An assessment of larger groups is needed for confirmation and for analyses of subgroups using additional acute (ictal) versus only chronic VNS. If changes are also found with chronic stimulation only, similar effects may be expected also with non-invasive types of VNS (transcutaneous VNS which presently undergoes clinical investigation).