Abstracts

Rationale: When the diagnosis of psychogenic nonepileptic seizures (PNES) has been appropriately explained and accepted by the patient following video-EEG (VEEG) confirmation, several studies report that up to one-third of these patients can become seizure free during short term follow-up ?" often without any additional intervention (McKenzie et al., 2010; Kanner et al., 1999). However, there are limited data showing whether any pre-diagnosis clinical feature can influence PNES outcome following VEEG confirmation of the diagnosis. This study investigates the effects of pre-diagnosis illness perception upon short-term clinical outcomes following VEEG confirmation of PNES. Methods: From November 2013 to May 2016, we pursued a prospective, longitudinal study following 63 subjects diagnosed with PNES from their VEEG evaluation to three months post-discharge. Prior to explanation of the diagnosis, patients completed a five-point symptom attribution scale, with "5" indicating perception their attacks are exclusively physical in origin, and "4" indicating mostly physical in origin. Concurrently, patients also completed the Brief Illness Perception Questionnaire (BIPQ) prior to learning of their diagnosis. The diagnoses of PNES were then explained by the same clinician (DKC) to all study subjects. At three months post-discharge, the investigators administered the same questionnaires to the patients via telephone interview. An additional questionnaire regarding the current attack burden and interval mental health interventions was given. We performed the Mann-Whitney U test for statistical comparison of groups. Results: Prior to VEEG confirmation, 29 patients (group A) perceived their attacks to be exclusively ("5") or mostly ("4") physical in origin, while 34 patients (group B) did not. At 3 months post-discharge, patients who attributed a physical basis for their attacks prior to diagnosis (group A) endorsed significantly reduced PNES frequency (p = 0.034) and severity/intensity (p = 0.0083). Additionally, when comparing the difference between pre-diagnosis of 3 month post-discharge BIPQ scores, group A patient were more likely to perceive their attacks as affecting their lives less severely (p = 0.0198) and felt they had more control over their attacks (p = 0.03662). These improvements are not likely to be confounded by mental health interventions, since essentially the same proportion (~30%) of patients from each group started seeing a new therapist after VEEG confirmation of PNES. Conclusions: Patients' pre-diagnosis illness perception that their attacks are exclusive or mostly physical basis may be a clinical factor which can significantly influence post-discharge PNES frequency, severity/intensity, as well perceived impairment and control over their attacks. Awareness of pre-diagnosis illness perception may promote the development of a more tailored approach toward the diagnostic explanation and subsequent management of patients with PNES. Funding: none