Rationale: To identify predictors of Psychogenic Non-Epileptic Seizures (PNES) improvement and antiseizure drug (ASD) discontinuation in patients with PNES only, after EMU discharge. Methods: Chart review was undertaken in 271 consecutive patients with PNES confirmed during video-EEG telemetry in our EMU between May 2000 and April 2008. Patients with associated epileptic seizures or without two visits follow-up after discharge were excluded. PNES decrease or resolution over the preceding year and ASD reduction or discontinuation were assessed at admission, discharge and two follow-up visits. Their relationship with demographic and clinical variables were evaluated. Results: A total of 109 subjects were included. The mean age at PNES onset was 33 years old (range 6-90), at EMU admission 38.3 years (16-90), 70.6% were females and mean video-EEG length was 6.1 days and the minimum follow-up seven years. Sixty-four out of 73 (87.7%) subjects on ASD were able to reduce the number of ASDs at the time of the final visit, and 59 (80,8%) discontinued them completely. Fifty-one out of 108 patients (47.2%) reported a PNES decrease after their EMU stay and 28 (25.9%) experienced PNES resolution. Patients achieving ASD discontinuation had significantly more children, more subsequent EMU visits, less risk factors for epilepsy or structural MRI lesions, experienced a greater reduction of ASDs in the EMU, were on fewer ASDs at the time of EMU discharge, and had a greater reduction in their PNES (p< 0.05). On binary regression analysis, predictors of ASD discontinuation were the absence of minor head trauma and less ASDs at EMU discharge (p< 0.05), while there was a tendency for more children (p=0.06) and fewer ASDs at EMU admission (p=0.07). Patients whose PNES frequency improved were significantly younger at the time of PNES onset and EMU admission, were less likely to be unemployed, more likely to be married or cohabiting, less likely to report past minor head trauma or migraine, reported higher PNES frequency, had a shorter stay within the EMU and were more likely off ASDs at the moment of discharge (p< 0.05). On ordinal logistic regression, younger age at EMU admission (p< 0.001) and full-time working (p=0.01) emerged as predictive of PNES reduction.
The 28 subjects with complete resolution of the PNES had significantly shorter time with PNES, ASDs more often discontinued and fewer subsequent visits to the EMU (p< 0.05). They also tended to be younger at the time of EMU admission, less likely unemployed or with anxiety disorders, and had higher frequency of PNES. On binary regression analysis, predictors of PNES resolution were having full-time work (p=0.009), younger age at EMU admission (p=0.06) and reduced ASDs at the final visit (p=0.069). Conclusions: An early diagnosis of PNES, better social resources and less comorbidity, are associated with PNES resolution after a definitive diagnosis in the EMU. Fewer risk factors for epilepsy and lack of MRI structural abnormalities, as well as lower use or higher reduction of ASDs during the EMU stay, also predict ASD discontinuation in these patients. Funding: Please list any funding that was received in support of this abstract.: None.