Abstracts

Rationale: Psychogenic non-epileptic seizures (PNES) are a diagnostic and therapeutic challenge for the clinician, since they can mimic the full spectrum of epileptic seizures. To date, no scales are available to accurately assess the PNES. A validated scale assessing the psychogenic motor disorders has recently been reported (1). We adapted this scale to develop and test a clinimetric scale for PNES Methods: Patients were 46 woman and 14 men, ranging in age 17 to 85 years (38.9 ± 18.7). Eight out of 60 patients had both epileptic seizures and PNES. Eight PNES occurred spontaneously, 50 were induced by different suggestion manoeuvres. Patients were recorded according to a standardized video-EEG protocol. Three epileptologists independently rated these videotapes. The PNES scale rated the motor phenomena involving different body regions, the associated features (sphynteric incontinence, morsus, drooling, eye closure, hyperventilation, lament or crying) and the responsiveness. The relation between the PNES scale and the Clinical Global Impression Scale [CGI] (2) was examined. Interrater reliabilities of both PNES and CGI scales were then assessed (Kendall’s coefficient of concordance, Spearman correlation, and intraclass correlation coefficients). Results: Interrater agreements for presence or absence of each phenomenon ranged from 58.3 to 100%. Kendall’s concordance coefficients were 0.704 and 0.666 for total phenomenology and PNES scores, respectively. ICCs values for total phenomenology (0.536) and PNES scores(0.452) showed a significant interrater reliability (p<0.001). Spearman correlations between total PNES scores and CGI ratings for the three raters ranged from 0.311 to 0.606 (p<0.02) Conclusions: This new scale is proposed as a user-friendly and clinically sound instrument for the quantitative assessment of PNES. REFERENCES 1.Hinson VK, Cubo E, Comella CL, Goetz CG, Leurgans S. Rating scale for psychogenic movement disorders: scale development and clinimetric testing. Mov Disord. 2005; 20:1592-7. 2.Guy W. ECDEU Assessment manual for psychopharmacology. Washington, DC: US Government Printing Office; 1976.