Post-traumatic factors are involved in the evolution of the number of seizures in patients with PNES.

Objective: The purpose of this prospective study was to identify predictive factors of the evolution of the number of seizures.

Methods: We included 85 individuals with a diagnosis of Psychogenic Nonepileptic Seizure (PNES) who completed at least two clinical interviews spaced by 6 months during a 24-month follow-up. Participants underwent a structured interview with an experimented clinician in PNES to complete standardized evaluation and validated scales. We collected sociodemographic and clinical data on PNES (number of seizures, duration of the disease), anxiety, depression, history of traumas, alexithymia, dissociation, and post-traumatic stress disorder (PTSD). We used a multivariate linear regression analysis to predict the characteristics independently associated with the evolution of the number of seizures in percentage.

Results: Dissociation score was significantly associated with a negative evolution of the number of seizures (p < 0.002). Conversely, the diagnosis of PTSD at inclusion was correlated to a positive evolution of the number of seizures (p < 0.029).

Conclusion: Dissociation was related to a more pejorative evolution of the number of seizures while PTSD diagnosis was associated with a decreased number of seizures. It is therefore essential to improve detection and treatment of post-traumatic dissociation. Further studies are required to understand the impact of PTSD on the evolution of the number of seizures.