Abstracts

Rationale: The prevalence of depression in patients with seizures is estimated to be 3-9% in those with well-controlled epilepsy, 20-55% in individuals with refractory epilepsy, and 20-40% in those with psychogenic nonepileptic seizures (PNES) who are referred to epilepsy centers. Depressive symptomatology has a significant negative impact on patients with seizures. Suicide is approximately 5-10 times more common among individuals with epilepsy than the general population and studies suggest that depression is more closely related than seizure frequency to poor quality of life among individuals with epilepsy. Depression is a multidimensional condition encompassing affective, physiological, and cognitive symptoms and although depression’s high comorbidity with both epileptic seizures (ES) and PNES has been established, few studies have addressed whether the types of depressive symptoms experienced differ by seizure type.Methods: The present research retrospectively examined the self-reported depressive symptomatology of patients (n=60 ES and 56 PNES) who underwent video-EEG monitoring and completed neuropsychological testing including self-report objective measures of psychopathology [Beck Depression Inventory-Second Edition (BDI-II); Personality Assessment Inventory (PAI)]. Differences in self-reported depressive symptoms were compared between the ES vs. PNES groups, as well as among several subgroups with ES (i.e., temporal vs. extra-temporal, right MTS vs. left MTS, and partial vs. generalized onset). Results: The PNES group endorsed a significantly higher level of physiological symptoms of depression as measured by the PAI DEP-P subscale than the ES group (PNES mean T=60.8, SD=11.6; ES mean T=55.6, SD=12.7; [t(114)=-2.33, p < .05]). No statistically significant differences were observed between the PNES and ES patients on the BDI-II total score, PAI DEP clinical scale, or the other 2 PAI DEP subscales. Comparison of the ES subgroups’ self-reported depressive symptoms did not yield statistically significant differences on any of the measures. Conclusions: Although the BDI-II total score did not evidence a significant difference between the ES and PNES groups, depression measures that parse out different types of depressive symptoms, such as the PAI subscales, distinguished between these two groups. Relative to normative data, the self-reported level of depressive symptoms was at the upper end of normal limits for both patient groups on measures that utilize a total score; and when the different dimensions of depressive symptoms were considered, the PNES group endorsed a mildly elevated rate of physiological symptoms. No evidence was found for differences in depressive symptoms among patients with different types of ES in the present study, possible due to limited sample sizes in these subgroups. These findings highlight the importance of multidimensional assessment of depressive symptoms.