Abstracts

Rationale: A subset of patients with pharmacoresistant epilepsy have comorbid psychogenic non-epileptic seizures (PNES). The benefit of epilepsy surgery in this population is unclear. Only a few small retrospective case series exist but none confirm PNES diagnosis with video EEG in all patients, none address outcomes of quality of life, functional capacity, or utilization of healthcare resources, and some use controversial induction procedures. The most recently published series of 9 patients in 2015 concluded that comorbid PNES should be a relative contraindication to epilepsy surgery (Whitehead K, et al. Impact of psychogenic nonepileptic seizures on epilepsy presurgical investigation and surgical outcomes. Epilepsy & Behavior. 2015; 46: 246-248). Methods: Cases of adult patients admitted to the Cleveland Clinic Epilepsy Monitoring Unit with video EEG confirmation of both epileptic seizures and PNES between 1/1/2009 and 12/31/2014 were retrospectively reviewed. Patients were excluded if no follow-up data was available or if PNES started after epilepsy surgery. Endpoints of interest are health status measures routinely collected from all patients seen in our center by questionnaire at outpatient clinic visits. The primary endpoint is change in quality of life as measured by the Quality of Life in Epilepsy questionnaire (QOLIE-10). Secondary endpoints include seizure and spell frequency, functional capacity as represented by ability to drive and work, and healthcare utilization as measured by seizure-related emergency visits and hospitalizations. Results: Please reference Table 1. Initial review found 171 patients with epileptic and nonepileptic events recorded. Nonepileptic events were potentially physiological (e.g. syncope, migraine, etc.) in 129 patients. Three patients did not have follow-up data. The remaining 39 patients with confirmed PNES were divided into group 1 who underwent epilepsy surgery (16 patients) and group 2 with no surgical intervention (23 patients) for analysis. Comparison of groups showed significant differences in the etiology of epilepsy (p = 0.008), with group 2 encompassing all patients with generalized epilepsies. Though the types of episodes were not reliably distinguishable by patients, a larger proportion who underwent epilepsy surgery (40%) reported complete freedom of both epileptic seizures and PNES at mean follow-up of 26 months (p = 0.013) as opposed to 5% in the nonsurgical group at mean follow-up of 33 months (Figure 1). There was a trend toward improving quality of life scores after surgical intervention, though not directly correlated with freedom of seizures and PNES, and not reaching statistical significance. More patients in the surgical group were driving at follow-up, but there was no difference in those working. There were less patients with seizure-related Emergency Department visits and hospital admissions in the surgical group in the 3 months before the last visit compared to the nonsurgical group. Conclusions: Surgery was effective in managing epilepsy in patients with comorbid PNES and epileptic seizures and invariably resulted in a decrease of PNES. Despite the inherent small sample size, it is clear some patients with comorbid epilepsy and PNES have significant benefit from epilepsy surgery. Comorbid psychogenic episodes, no matter how frequent, should not be considered a contraindication to epilepsy surgery. The benefits of epilepsy surgery for quality of life, functional capacity, and health care utilization were less robust than direct correlation with seizure freedom, but overall the trends appear favorable after surgical intervention. Funding: none