Different dissociation and alexithymia domains specifically relate to patients with psychogenic non-epileptic seizures (PNES) and with PNES and comorbid epilepsy (PNES+EP)

Background: Several studies previously examined the role of dissociation and alexithymia in patients with psychogenic non-epileptic seizures (PNES). However, their relationship remains unclear. Methods: We administered questionnaires for dissociation (DES-II), alexithymia (TAS-20), anxiety and depression to 57 subjects: 14 patients with PNES, 13 patients with comorbid PNES and epilepsy (PNES+EP), 14 patients with EP and 16 healthy controls. For between-group comparisons we applied Chi-square test, ANOVA and Kruskal-Wallis. The Spearman correlations, hierarchical regression analyses and path models, goodness-of-fit indices and maximum-likelihood estimates of model parameters were obtained through SPSS 27 and AMOS 27. Results: Hierarchical regression analyses showed that nor DES-II neither TAS-20 total scores were able to predict TAS-20 and DES-II total scores, respectively, possibly due to subscale score pooling. Following modification indexes of AMOS 27, in PNES sample, we found that only Depersonalization/Derealization (Dep/Der) was fully mediated by Difficulty Identifying Feelings (DIF) and Absorption (Abs) in predicting Difficulty Describing Feelings (DDF), and a partial effect of DIF and Dep/Der implement DDF, while both DIF and DDF implement Abs. In PNES+EP group, Dep/Der was able to predict DDF, with a partial mediation of Abs that predicted Externally Oriented Thinking, while DDF was able to promote Abs, and DIF effect on Abs was fully mediated by Amnesia (Amn). Limitations: Our study is cross-sectional, participants were self-selected and the data were derived from self-report measures. Conclusions: In PNES, Dep/Der and DIF may play a prominent role, while in PNES+EP, Dep/Der, Abs, DIF and Amn may be involved. Clinical implications are discussed.