Abstracts

Rationale: Early diagnosis of patients with psychogenic non-epileptic seizures (PNES) improves clinicians' ability to start appropriate treatment. Early, appropriate treatment improves long-term seizure prognosis. Patients with PNES have increased visceral sensitivity and report more positive complaints on review-of-systems questionnaires (RoSQs) than other patients with seizures. If the responses on the RoSQ can differentiate PNES from other seizure types, then these forms could be an early screening tool to improve the identification, treatment and, consequently, prognosis of patients with PNES. Methods: Our dataset included all patients admitted January 2006 to March 2016 for video-electroencephalography at UCLA. RoSQs prior to May 2015 were acquired through retrospective chart review (n=405), whereas RoSQs from subsequent patients were acquired prospectively (n=117). Controlling for sex and number of comorbidities, we used binomial regression to compare the total number of symptoms and the frequency of specific symptoms between five mutually exclusive groups of patients: epileptic seizures (ES), PNES, physiologic non-epileptic seizure-like events (PSLE), mixed PNES plus ES, and inconclusive monitoring. To determine the diagnostic utility of RoSQs to differentiate PNES only from ES only, we used multivariate logistic regression, controlling for sex and the number of medical comorbidities. Results: On average, patients with PNES or mixed PNES plus ES reported more than twice as many symptoms as patients with isolated ES or PSLE (p < 0.001). However, the prospective accuracy to differentiate PNES from ES was not significantly higher than naﶥ accuracy (76% vs 69%, p>0.1). The predictive value and sensitivity for ES of noting fewer symptoms was 76% (95% CI 66-87%) and 93% (95% CI 85-99%), respectively. Conclusions: This analysis of RoSQs confirms that patients with PNES with and without comorbid ES report more symptoms on a population level than patients with epileptic seizures or physiologic seizure-like events. This likely represents nonspecific conversion disorder or increased visceral sensitivity. While these differences help describe the population of patients with PNES, the consistency of RoSQ responses was not accurate or specific enough for it to be used as an early screening tool for PNES. The high predictive value for ES suggests that most patients with relatively few RoSQ symptoms have epileptic seizures. Funding: NIH T32 GM08042, NIH T90 DA022768, NIH R90 DA022768, NIH R90 DA023422, NS03310, NS080181, UCLA Departments of Psychiatry & Biobehavioral Sciences and Biomathematics.