Personality profiles differ between patients with epileptic seizures and patients with psychogenic non-epileptic seizures
Authors: Leong Michelle , Wang Albert D , Trainor David , Johnstone Ben , Rayner Genevieve , Kalincik Tomas , Roos Izanne , Kwan Patrick , O’Brien Terence J , Velakoulis Dennis , Malpas Charles B 
Published: July 2019

Aim

The primary aim of the study was to determine whether patients with psychogenic non-epileptic seizures (PNES) have different personality profiles compared to patients with epileptic seizures (ES). The secondary aim was to determine whether any such personality differences could be used to efficiently screen for PNES in clinical settings.

Background

PNES and ES are often difficult to differentiate, leading to incorrect or delayed diagnosis. While the current gold-standard investigation is video-EEG monitoring (VEM), it is resource intensive and not universally available. Although some research has investigated the differential psychological profiles of PNES and ES patients, most studies have focused on symptoms of psychopathology. The lack of research using modern personality models in PNES and ES presents a gap in knowledge that this study aimed to address.

Methods

A retrospective collection of data was conducted on patients who completed the NEO-Five Factor Inventory questionnaire during a VEM admission to the Royal Melbourne Hospital between 2002-2017. Patients were classified as either ES or PNES based on clinical consensus diagnosis. For patients with ES, type of epilepsy and laterality of seizure focus were also recorded. Personality differences were investigated using Bayesian linear mixed effects models. Receiver operating characteristic curve analysis was also performed to generate sensitivities and specificities of individual personality scores.

Results

305 patients were included in the study. The ‘openness to experience’ domain was the only personality factor demonstrating strong evidence for a group difference (BF10 = 21.55, d = −0.43 [95% CI −0.71, −0.17]), with patients in the PNES group having higher scores compared to the ES group. Within the openness to experience domain, only the ‘aesthetic interest’ facet showed evidence for a group difference (BF10 = 7.98, d = −0.39 [95% CI −0.66, −0.12]). ES patients had lower scores on these measures compared to the normal population, while PNES patients did not. Both openness to experience and aesthetic interest, however, showed poor sensitivities (53%, 46% respectively) and specificities (69%, 46% respectively) for classifying PNES and ES patients. There were no differences between personality profiles in Temporal Lobe Epilepsy (TLE) and non-TLE patients, or in laterality in TLE.

Conclusion

Patients with ES exhibit lower openness to experience and aesthetic interest compared to patients with PNES and compared to the general population. Despite these differences, the relatively low sensitivity and specificity of these instruments suggests their use is limited in a clinical setting. Nevertheless, these findings open up new avenues of research using modern personality models to further understand patients with epilepsy and related presentations.