Dissociative and associated psychopathological symptoms in patients with epilepsy, pseudoseizures, and both seizure forms

Dissociation in patients with epilepsy and functional seizures: A narrative review of the literature

Dissociation is a "disruption of the usually integrated functions of consciousness, memory, identity or perception of the environment" according to DSM-5.  It is commonly seen in psychiatric disorders including primary dissociative disorders, post-traumatic stress disorder, depression, and panic disorder. Dissociative phenomena are also described in the context of substance intoxication, sleep deprivation and medical illnesses including traumatic brain injury, migraines, and epilepsy. Patients with epilepsy have higher rates of dissociative experiences as measured on the Dissociative Experiences Scale compared to healthy controls. Ictal symptoms, especially in focal epilepsy of temporal lobe origin, may include dissociative-like experiences such as déjà vu/jamais vu, depersonalization, derealization and what has been described as a "dreamy state".  These descriptions are common in the setting of seizures that originate from mesial temporal lobe epilepsy and may involve the amygdala and hippocampus. Other ictal dissociative phenomena include autoscopy and out of body experiences, which are thought to be due to disruptions in networks responsible for the integration of one's own body and extra-personal space and involve the temporoparietal junction and posterior insula. In this narrative review, we will summarize the updated literature on dissociative experiences in epilepsy, as well as dissociative experiences in functional seizures. Using a case example, we will review the differential diagnosis of dissociative symptoms. We will also review neurobiological underpinnings of dissociative symptoms across different diagnostic entities and discuss how ictal symptoms may shed light on the neurobiology of complex mental processes including the subjective nature of consciousness and self-identity.

Multidimensional psychopathological profile differences between patients with psychogenic nonepileptic seizures and epileptic seizure disorders

OBJECTIVE

Early differential diagnosis of psychogenic nonepileptic seizures (PNES) and epileptic seizures (ES) remains difficult. Self-reported psychopathology is often elevated in patients with PNES, although relatively few studies have examined multiple measures of psychopathology simultaneously. This study aimed to identify differences in multidimensional psychopathology profiles between PNES and ES patient groups.

METHOD

This was a retrospective case-control study involving patients admitted for video-EEG monitoring (VEM) over a two-year period. Clinicodemographic variables and psychometric measures of depression, anxiety, dissociation, childhood trauma, maladaptive personality traits, and cognition were recorded. Diagnosis of PNES or ES was determined by multidisciplinary assessment and consensus opinion. General linear mixed models (GLMMs) were used to investigate profile differences between diagnostic groups across psychometric measures. A general psychopathology factor was then computed using principal components analysis (PCA) and differences between groups in this 'p' factor were investigated.

RESULTS

261 patients (77 % with ES and 23 % with PNES) were included in the study. The PNES group endorsed greater symptomatology with GLMM demonstrating a significant main effect of group (η²_p = 0.05) and group by measure interaction (η²_p = 0.03). Simple effects analysis indicated that the PNES group had particularly elevated scores for childhood trauma (β = 0.78), dissociation (β = 0.70), and depression (β = 0.60). There was a high correlation between psychopathology measures, with a single p factor generated to explain 60 % variance in the psychometric scores. The p factor was elevated in the PNES group (β = 0.61). ROC curve analysis indicated that these psychometric measures had limited usefulness when considered individually (AUC range = 0.63-0.69).

CONCLUSION

Multidimensional psychopathological profile differences exist between patients with PNES and ES. Patients with PNES report more psychopathology overall, with particular elevations in childhood trauma, dissociation, and depression. Although not suitable to be used as a standalone screening tool to differentiate PNES and ES, understanding of these profiles at a construct level might help triage patients and guide further psychiatric examination and enquiry.

Evidence-Based Practice for the Clinical Assessment of Psychogenic Nonepileptic Seizures: A Report From the American Neuropsychiatric Association Committee on Research

The American Neuropsychiatric Association's Committee on Research assigned the task of defining the most helpful clinical factors and tests in establishing the diagnosis of psychogenic nonepileptic seizures (PNES) during a neuropsychiatric assessment. A systematic review of the literature was conducted using three search engines and specified search terms for PNES and the predetermined clinical factors and diagnostic tests, followed by a selection process with specific criteria. Data extraction results from selected articles are presented for clinical factors (semiology, psychiatric comorbidities, medical comorbidities, psychological traits) and diagnostic tests (EEG, psychometric and neuropsychological measures, prolactin level, clinical neuroimaging, autonomic testing). Semiology with video EEG (vEEG) remains the most valuable tool to determine the diagnosis of PNES. With the exception of semiology, very few studies revealed the predictive value of a clinical factor for PNES, and such findings were isolated and not replicated in most cases. Induction techniques, especially when coupled with vEEG, can lead to a captured event, which then confirms the diagnosis. In the absence of a captured event, postevent prolactin level and personality assessment can support the diagnosis but need to be carefully contextualized with other clinical factors. A comprehensive clinical assessment in patients with suspected PNES can identify several clinical factors and may include a number of tests that can support the diagnosis of PNES. This is especially relevant when the gold standard of a captured event with typical semiology on vEEG cannot be obtained.

Emotion dysregulation in patients with psychogenic nonepileptic seizures: A systematic review based on the extended process model

Psychogenic nonepileptic seizures (PNES) are characterized by paroxysmal alterations in motor and sensory functions resembling epileptic seizures, but are not caused by epileptiform activity. In recent years, there has been increasing scientific interest in emotion dysregulation in patients with PNES (pwPNES), but the literature has not yet been interpreted within a broader model of emotion dysregulation. The aim of this review was therefore to synthesize the existing literature on emotion dysregulation in pwPNES within the extended process model (EPM) of emotion regulation.

METHODS

PubMed and Web of Science were searched for studies relevant to emotion dysregulation as defined by the EPM. These studies were subjected to a bespoke quality appraisal tool. Studies of acceptable quality were categorized to the different stages of the EPM and critically appraised.

RESULTS

Studies of emotion regulation in pwPNES were generally of low quality - a finding largely driven by small sample sizes. However, there was evidence of emotion dysregulation characterized by deficits in the identification of patients' own emotional states, as well as the selection and implementation of maladaptive regulatory strategies, and altered exteroceptive emotional processing. However, heterogeneity in findings suggests that emotion dysregulation is likely linked to other psychological factors and not common to all pwPNES.

SIGNIFICANCE

This review suggests that while pwPNES are likely to experience emotion dysregulation as defined by the EPM, there is variability in the distribution of regulatory deficits in this patient population, and a person-centered approach should be taken when working with these patients. There is a need for more high quality and better-powered studies in this area.

Identifying psychogenic seizures through comorbidities and medication history

OBJECTIVE

Low-cost evidence-based tools are needed to facilitate the early identification of patients with possible psychogenic nonepileptic seizures (PNES). Prior to accurate diagnosis, patients with PNES do not receive interventions that address the cause of their seizures and therefore incur high medical costs and disability due to an uncontrolled seizure disorder. Both seizures and comorbidities may contribute to this high cost.

METHODS

Based on data from 1,365 adult patients with video-electroencephalography-confirmed diagnoses from a single center, we used logistic and Poisson regression to compare the total number of comorbidities, number of medications, and presence of specific comorbidities in five mutually exclusive groups of diagnoses: epileptic seizures (ES) only, PNES only, mixed PNES and ES, physiologic nonepileptic seizurelike events, and inconclusive monitoring. To determine the diagnostic utility of comorbid diagnoses and medication history to differentiate PNES only from ES only, we used multivariate logistic regression, controlling for sex and age, trained using a retrospective database and validated using a prospective database.

RESULTS

Our model differentiated PNES only from ES only with a prospective accuracy of 78% (95% confidence interval =72-84%) and area under the curve of 79%. With a few exceptions, the number of comorbidities and medications was more predictive than a specific comorbidity. Comorbidities associated with PNES were asthma, chronic pain, and migraines (p < 0.01). Comorbidities associated with ES were diabetes mellitus and nonmetastatic neoplasm (p < 0.01). The population-level analysis suggested that patients with mixed PNES and ES may be a population distinct from patients with either condition alone.

SIGNIFICANCE

An accurate patient-reported medical history and medication history can be useful when screening for possible PNES. Our prospectively validated and objective score may assist in the interpretation of the medication and medical history in the context of the seizure description and history.

Dissociation in patients with dissociative seizures: relationships with trauma and seizure symptoms

BACKGROUND

This study aimed to extend the current understanding of dissociative symptoms experienced by patients with dissociative (psychogenic, non-epileptic) seizures (DS), including psychological and somatoform types of symptomatology. An additional aim was to assess possible relationships between dissociation, traumatic experiences, post-traumatic symptoms and seizure manifestations in this group.

METHOD

A total of 40 patients with DS were compared with a healthy control group (n = 43), matched on relevant demographic characteristics. Participants completed several self-report questionnaires, including the Multiscale Dissociation Inventory (MDI), Somatoform Dissociation Questionnaire-20, Traumatic Experiences Checklist and the Post-Traumatic Diagnostic Scale. Measures of seizure symptoms and current emotional distress (Hospital Anxiety and Depression Scale) were also administered.

RESULTS

The clinical group reported significantly more psychological and somatoform dissociative symptoms, trauma, perceived impact of trauma, and post-traumatic symptoms than controls. Some dissociative symptoms (i.e. MDI disengagement, MDI depersonalization, MDI derealization, MDI memory disturbance, and somatoform dissociation scores) were elevated even after controlling for emotional distress; MDI depersonalization scores correlated positively with trauma scores while seizure symptoms correlated with MDI depersonalization, derealization and identity dissociation scores. Exploratory analyses indicated that somatoform dissociation specifically mediated the relationship between reported sexual abuse and DS diagnosis, along with depressive symptoms.

CONCLUSIONS

A range of psychological and somatoform dissociative symptoms, traumatic experiences and post-traumatic symptoms are elevated in patients with DS relative to healthy controls, and seem related to seizure manifestations. Further studies are needed to explore peri-ictal dissociative experiences in more detail.

Diagnostic implications of review-of-systems questionnaires to differentiate epileptic seizures from psychogenic seizures

OBJECTIVE

Early and accurate diagnosis of patients with psychogenic nonepileptic seizures (PNES) leads to appropriate treatment and improves long-term seizure prognosis. However, this is complicated by the need to record seizures to make a definitive diagnosis. Suspicion for PNES can be raised through knowledge that patients with PNES have increased somatic sensitivity and report more positive complaints on review-of-systems questionnaires (RoSQs) than patients with epileptic seizures. If the responses on the RoSQ can differentiate PNES from other seizure types, then these forms could be an early screening tool.

METHODS

Our dataset included all patients admitted from January 2006 to June 2016 for video-electroencephalography at UCLA. RoSQs prior to May 2015 were acquired through retrospective chart review (n=405), whereas RoSQs from subsequent patients were acquired prospectively (n=190). Controlling for sex and number of comorbidities, we used binomial regression to compare the total number of symptoms and the frequency of specific symptoms between five mutually exclusive groups of patients: epileptic seizures (ES), PNES, physiologic nonepileptic seizure-like events (PSLE), mixed PNES plus ES, and inconclusive monitoring. To determine the diagnostic utility of RoSQs to differentiate PNES only from ES only, we used multivariate logistic regression, controlling for sex and the number of medical comorbidities.

RESULTS

On average, patients with PNES or mixed PNES and ES reported more than twice as many symptoms than patients with isolated ES or PSLE (p<0.001). The prospective accuracy to differentiate PNES from ES was not significantly higher than naïve assumption that all patients had ES (76% vs 70%, p>0.1).

DISCUSSION

This analysis of RoSQs confirms that patients with PNES with and without comorbid ES report more symptoms on a population level than patients with epilepsy or PSLE. While these differences help describe the population of patients with PNES, the consistency of RoSQ responses was neither accurate nor specific enough to be used solely as an early screening tool for PNES. Our results suggest that the RoSQ may help differentiate PNES from ES only when, based on other information, the pre-test probability of PNES is at least 50%.

Psychological and psychiatric aspects of psychogenic non-epileptic seizures (PNES): A systematic review

Psychogenic non-epileptic seizures (PNES) are common in neurological settings and often associated with considerable distress and disability. The psychological mechanisms underlying PNES are poorly understood and there is a lack of well-established, evidence-based treatments. This paper advances our understanding of PNES by providing a comprehensive systematic review of the evidence pertaining to the main theoretical models of this phenomenon. Methodological quality appraisal and effect size calculation were conducted on one hundred forty empirical studies on the following aspects of PNES: life adversity, dissociation, anxiety, suggestibility, attentional dysfunction, family/relationship problems, insecure attachment, defence mechanisms, somatization/conversion, coping, emotion regulation, alexithymia, emotional processing, symptom modelling, learning and expectancy. Although most of the studies were only of low to moderate quality, some findings are sufficiently consistent to warrant tentative conclusions: (i) physical symptom reporting is elevated in patients with PNES; (ii) trait dissociation and exposure to traumatic events are common but not inevitable correlates of PNES; (iii) there is a mismatch between subjective reports of anxiety and physical arousal during PNES; and (iv) inconsistent findings in this area are likely to be attributable to the heterogeneity of patients with PNES. Empirical, theoretical and clinical implications are discussed.

Dissociative experiences in patients with epilepsy

A few studies have explored dissociative experiences in epilepsy patients. We investigated dissociative experiences in patients with epilepsy using the dissociative experiences scale (DES). Ninety-eight patients with epilepsy and sixty healthy controls were enrolled in this study. A sociodemographic questionnaire and the Dissociative Experiences Scale (DES), Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI) were administered to the participants. The DES scores were significantly higher for the patients with epilepsy than the healthy individuals. The number of individuals with pathological dissociation (DES ≥ 30) was higher in the epilepsy group (n = 28) than in the control group (n = 8). Also, higher levels of dissociation were significantly associated with frequency of seizures, but were not associated with duration of epilepsy and age at onset of the disorder. These findings demonstrate that patients with epilepsy are more prone to dissociation than controls. The high rate of dissociative experiences among patients with epilepsy suggest that some epilepsy-related factors are present.

Nonepileptic seizures - subjective phenomena

Psychogenic nonepileptic seizures (PNES) superficially resemble epileptic seizures or syncope and most patients with PNES are initially misdiagnosed as having one of the latter two types of transient loss of consciousness. However, evidence suggests that the subjective seizure experience of PNES and its main differential diagnoses are as different as the causes of these three disorders. In spite of this, and regardless of the fact that PNES are considered a mental disorder in the current nosologies, research has only given limited attention to the subjective symptomatology of PNES. Instead, most phenomenologic research has focused on the visible manifestations of PNES and on physiologic parameters, neglecting patients' symptoms and experiences. This chapter gives an overview of qualitative and quantitative studies providing insights into subjective symptoms associated with PNES, drawing on a wide range of methodologies (questionnaires, self-reports, physiologic measures, linguistic analyses, and neuropsychologic experiments). After discussing the scope and limitations of these approaches in the context of this dissociative phenomenon, we discuss ictal, peri-ictal and interictal symptoms described by patients with PNES. We particularly focus on impairment of consciousness. PNES emerges as a clinically heterogeneous condition. We conclude with a discussion of the clinical significance of particular subjective symptoms for the engagement of patients in treatment, the formulation of treatment, and prognosis.

Thoughts, emotions, and dissociative features differentiate patients with epilepsy from patients with psychogenic nonepileptic spells (PNESs)

Psychogenic nonepileptic spells (PNESs) are often very difficult to treat, which may be, in part, related to the limited information known about what a person experiences while having PNESs. For this retrospective study, thoughts, emotions, and dissociative features during a spell were evaluated in 351 patients diagnosed with PNESs (N=223) or epilepsy (N=128). We found that a statistically higher number of thoughts, emotions, and dissociative symptoms were endorsed by patients with PNESs versus patients with epilepsy. Patients with PNESs reported significantly more anxiety and frustration, but not depression, compared with those with epilepsy. Emotions and dissociations, but not thoughts, and a history of any type of abuse were endorsed significantly more often by patients with PNESs. Patients with PNESs are prone to having poor outcomes, and interventions focusing on their actual experiences may be helpful for treatment planning.

Dissociative experiences in epilepsy: effects of epilepsy-related factors on pathological dissociation

Psychogenic nonepileptic seizures (PNESs) in patients with epilepsy can be categorized as dissociative disorders. The prevalence of PNESs in patients with epilepsy appears to be much higher than that of dissociative experiences in nonclinical subjects. In order to clarify as to whether epilepsy-related factors were associated with pathological dissociation, we conducted a controlled study with 225 patients with epilepsy and 334 nonclinically matched individuals. All participants completed the Japanese version of the Dissociative Experiences Scale (DES). There was no significant difference in the DES score (DES-S) between the group with epilepsy and the control group. The group with epilepsy showed a significantly higher DES taxon (DES-T; a subset of DES-S and an index of pathological dissociation) than the control group. Thirty-one out of the 225 patients with epilepsy (13.8%) had PNESs. Because of its strong association with the DES-S and DES-T, PNESs can be regarded as a symptom of dissociation. With multiple regression analysis, the patients with a shorter duration of epilepsy, higher seizure frequency, or shorter period in education tend to suffer from pathological dissociation. These findings demonstrate that patients with epilepsy are more prone to experiencing pathological dissociation when having certain clinical factors.

Cognitive impairment and evaluation in psychogenic nonepileptic seizures: an integrated cognitive-emotional approach

Neuropsychological studies comparing patients with psychogenic nonepileptic seizures (PNES) to those with epilepsy have been largely equivocal. The variability in the neuropsychological literature highlights the heterogeneity of the PNES population across a number of psychiatric and neurologic factors. Phenotypic presentations in PNES arise from complex interactions between vulnerable cognitive and emotional systems. We propose that variability in neuropsychological findings in PNES emerge in the context of diverse psychiatric, neurologic, and clinical factors. Traditional assessments that fail to integrate cognitive and emotional/behavioral profiles sufficiently would fall short in characterizing the complexity of brain-behavior relationships in this population. To advance the neuropsychology of PNES, we propose a systematic approach to measure a number of factors that influence cognitive impairment in this population. We begin by reviewing the current neuropsychological literature in PNES and discussing a number of factors that influence cognitive deficits. We then present a comprehensive neuropsychological battery designed to capture elements (cognitive dysfunction, psychopathology, emotion processing deficits) underlying the proposed vulnerable cognitive-emotional system in PNES. It is our hope that the proposed battery will facilitate the aggregation of data across neuropsychological investigations, to allow more advanced statistical analyses, and ultimately enhance our understanding of PNES and the development of effective management and treatment options.

Dissociative experiences in epilepsy--a neuropathological and sociodemographic study in a Chinese population

BACKGROUND

It is well known that dissociative experiences coexist with various epilepsy syndromes. However, the prevalence of dissociative experiences in different subtypes of epilepsy remains unknown. This is especially important because of the current prevalent view that the etiology of dissociation in seizures is neurobiological rather than psychosocial. The amygdala especially has been implicated in such dissociative features of epilepsy. This would indirectly imply that the patients with CPS have higher prevalence of dissociative symptoms compared with those with GTCS.

METHODOLOGY

We studied and compared the dissociative experiences as well as the depression and anxiety levels between 24 patients suffering from temporal lobe epilepsy and 26 patients suffering from generalized tonic-clonic seizures. We used the Dissociative Experiences Scale to evaluate the dissociative experiences. A third group of healthy individuals was included as the control group. The statistical significance was fixed at 0.05.

RESULTS

There were significant differences between the scores of DES-II of the healthy individuals and those of patients with epilepsy. However, there were no significant differences between the DES scores of different patients with epilepsy categorized according to neuropathology. There were also no significant differences between HAM-A and HAM-D scores between groups with epilepsy, but the scores were higher than those of the healthy individuals. There were significant differences between the DES scores in different sociodemographic groups such that higher scores were observed in groups with lower education (p<0.05). In addition, the scores on DES were higher in individuals with low socioeconomic status than in those with high socioeconomic status.

CONCLUSION

The patients with temporal lobe epilepsy and those with generalized tonic-clonic seizures have similar dissociative experiences which are both more than those found in individuals without epilepsy. However, these dissociative experiences may not be related to the neuropathological parameters as much as they are to the sociodemographic parameters like education, age, socioeconomic status, and sex. This shows that the psychopathology of dissociation in epilepsy is similar to that of the general population.

Resting-state networks and dissociation in psychogenic non-epileptic seizures

OBJECTIVE

Psychogenic non-epileptic seizures (PNES) are epilepsy-like episodes which have an emotional rather than organic origin. Although PNES have often been related to the process of dissociation, the psychopathology is still poorly understood. To elucidate underlying mechanisms, the current study applied independent component analysis (ICA) on resting-state fMRI to investigate alterations within four relevant networks, associated with executive, fronto-parietal, sensorimotor, and default mode activation, and within a visual network to examine specificity of between-group differences.

METHODS

Twenty-one patients with PNES without psychiatric or neurologic comorbidities and twenty-seven healthy controls underwent resting-state functional MR imaging at 3.0T (Philips Achieva). Additional neuropsychological testing included Raven's Matrices test and dissociation questionnaires. ICA with dual regression was used to identify resting-state networks in all participants, and spatial maps of the networks of interest were compared between patients and healthy controls.

RESULTS

Patients displayed higher dissociation scores, lower cognitive performance and increased contribution of the orbitofrontal, insular and subcallosal cortex in the fronto-parietal network; the cingulate and insular cortex in the executive control network; the cingulate gyrus, superior parietal lobe, pre- and postcentral gyri and supplemental motor cortex in the sensorimotor network; and the precuneus and (para-) cingulate gyri in the default-mode network. The connectivity strengths within these regions of interest significantly correlated with dissociation scores. No between-group differences were found within the visual network, which was examined to determine specificity of between-group differences.

CONCLUSIONS

PNES patients displayed abnormalities in several resting-state networks that provide neuronal correlates for an underlying dissociation mechanism.

Comparisons of childhood trauma, alexithymia, and defensive styles in patients with psychogenic non-epileptic seizures vs. epilepsy: Implications for the etiology of conversion disorder

BACKGROUND

It has been theorized that conversion disorder is the result of emotion that cannot be experienced consciously as feeling states or put into words (i.e., alexithymia), but there is little confirming empirical evidence. We sought to characterize subjects with conversion disorder compared to subjects with a distinct medical illness, using the model of psychogenic non-epileptic seizures (PNES) vs. epilepsy (ES), on measures of childhood traumatic experience, alexithymia and maturity of psychological defensive strategies.

METHODS

All subjects admitted to the Epilepsy Monitoring Unit of the University of Cincinnati Medical Center were offered self-report questionnaires (Childhood Trauma Questionnaire, Toronto Alexithymia Scale-20 and Response Evaluation Measure-71) at the outset of evaluation. Diagnosis of each subject was confirmed by video-EEG and we compared subjects with PNES to those with ES on these measures.

RESULTS

82 subjects had ES AND 96 had PNES. Those with PNES were significantly more likely to have experienced childhood trauma in all domains (p=.005 to p=.05), and were significantly more likely to have alexithymia (p=.0267). There was a significant difference in the capacity to identify feelings, and a trend towards significance in capacity to describe feelings. There were no differences in defensive styles between the two groups.

CONCLUSIONS

PNES diagnosis was associated with female sex, higher alexithymia scores and higher rates of childhood trauma, but not with differences in defensive styles compared to ES. These findings add empirical evidence for theories regarding the cause of conversion disorder and may aid in the design of prospective treatment trials in patients with conversion disorder.

Dissociative experiences and quality of life in patients with non-epileptic attack disorder

Dissociative experiences are commonly reported by patients with non-epileptic attack disorder (NEAD). This cross-sectional study examined the prevalence and characteristics of dissociative experiences in patients with NEAD and assessed their association with health-related quality of life (HRQoL). Fifty-three patients diagnosed with NEAD were consecutively recruited (70.0% female, mean age=42 years, 22.0% with comorbid epilepsy) from a specialist neuropsychiatric clinic. Our sample reported high levels of dissociative experiences, with 36.7% of patients scoring ≥30 on the Dissociative Experiences Scale (DES). Significant negative correlations were found between total DES scores and HRQoL, as measured by the QOLIE-31 questionnaire (r=-0.64, p<0.001). This association remained significant when accounting for symptoms of depression and anxiety, other psychiatric comorbidities, and attack frequency and severity. These findings suggest a high prevalence of dissociative experiences in this patient population, highlighting the importance of routinely screening patients for dissociative symptoms and their impact on patients' lives.

Epilepsy, mental health disorder, or both?

Temporal lobe epilepsy (TLE), a subset of the seizure disorder family, represents a complex neuropsychiatric illness, where the neurological presentation may be complemented by varying severity of affective, behavioral, psychotic, or personality abnormalities, which, in turn, may not only lead to misdiagnosis, but also affect the management. This paper outlines a spectrum of mental health presentations, including psychosis, mood, anxiety, panic, and dissociative states, associated with epilepsy that make the correct diagnosis a challenge.

Psychogenic nonepileptic seizures: characterization of two distinct patient profiles on the basis of trauma history

This prospective study investigated and compared psychiatric features of 25 consecutive patients with psychogenic nonepileptic seizures (PNES) on the basis of presence of reported trauma. The "trauma" group comprised 19 patients (76%) and the "no-trauma" group comprised 6 patients (34%). We compared history of PNES, psychiatric comorbidity, alexithymia, and symptoms of dissociation. The study clearly characterized two distinct profiles of patients with PNES on the basis of trauma history. Patients with trauma had at least one psychiatric comorbidity or antecedent (vs 0% in the no-trauma group NT, P<0.001) and a higher median score of dissociation (P<0.001). Patients without trauma had more frequent "frustration situations" as a factor triggering PNES and subsequent sick leaves as perpetuating factors (P=0.001). Trauma antecedents correlated with a high rate of psychiatric comorbidity and a strong dissociative mechanism. Patients without trauma had no psychiatric comorbidity and a weaker dissociative mechanism.

Rating scale for psychogenic nonepileptic seizures: scale development and clinimetric testing

Our aim was to develop a clinimetric scale evaluating motor phenomena, associated features, and severity of psychogenic nonepileptic seizures (PNES). Sixty video/EEG-recorded PNES induced by suggestion maneuvers were evaluated. We examined the relationship between results from this scale and results from the Clinical Global Impression (CGI) scale to validate this technique. Interrater reliabilities of the PNES scale for three raters were analyzed using the AC1 statistic, Kendall's coefficient of concordance (KCC), and intraclass correlation coefficients (ICCs). The relationship between the CGI and PNES scales was evaluated with Spearman correlations. The AC1 statistic demonstrated good interrater reliability for each phenomenon analyzed (tremor/oscillation, tonic; clonic/jerking, hypermotor/agitation, atonic/akinetic, automatisms, associated features). KCC and the ICC showed moderate interrater agreement for phenomenology, associated phenomena, and total PNES scores. Spearman's correlation of mean CGI score with mean total PNES score was 0.69 (P<0.001). The scale described here accurately evaluates the phenomenology of PNES and could be used to assess and compare subgroups of patients with PNES.

Emotional trauma and abuse in patients with psychogenic nonepileptic seizures

A history of childhood trauma and the presence of dissociative phenomena are considered to be the most important risk factors for psychogenic nonepileptic seizure disorder (PNESD). This case-control study investigated 20 patients with PNESD and 20 with temporal lobe epilepsy (TLE) diagnosed by video/EEG monitoring who were matched for gender and age. Patients with both conditions were not included in the study. Groups were evaluated for age at onset and at diagnosis, worst lifetime weekly seizure frequency, trauma history, and presence of dissociative phenomena. Age at onset (P=0.007) and age at diagnosis (P<0.001) were significantly higher in the PNESD group than the control group, as were the scores on the Dissociative Experiences Scale (P<0.001) and Childhood Trauma Questionnaire (P=0.014). Only the differences in scores on the Childhood Trauma Questionnaire subscales Emotional Neglect (P=0.013) and Emotional Abuse (P=0.014) reached statistical significance. Dissociative phenomena and a reported history of childhood trauma are more common in patients with PNESD than in those with TLE. However, only emotional neglect and abuse were associated with PNESD in this study.

[Psychogenic non-epileptic seizures: history and critique of a concept]

This discussion of the evolution of psychiatric knowledge concerning psychogenic non-epileptic seizures (PNES) sheds light on the epistemological assumptions underlying the concept and on its practical implications as well. PNES are defined as repeated seizures or attacks which can be mistaken for epilepsy because of the similar behavioral changes displayed, but which differ in that they are not the result of abnormal electrical activity in the brain and may be psychogenic in origin. The article investigates the historical development of the concept of PNES over the past forty years. The concepts of psychiatric comorbidity, abuse, and dissociation enter the discussion owing to their roles in the checkered development of the concept of PNES.

Evaluation of dissociative experiences and the clinical utility of the Dissociative Experience Scale in patients with coexisting epilepsy and psychogenic nonepileptic seizures

We investigated the relationship between dissociation and psychogenic nonepileptic seizures (PNES) and evaluated the clinical utility of the Dissociative Experience Scale (DES) in patients with epilepsy. The DES was administered to 30 patients with epilepsy and PNES, 50 patients with epilepsy and no PNES, and 85 nonclinical individuals. Patients with epilepsy and PNES scored significantly higher on the DES (29.3) than patients with epilepsy without PNES (13.5) and nonclinical individuals (11.1). High DES scores (>30) were more frequently observed in patients with epilepsy and PNES (53%) than in patients with epilepsy without PNES (12%) and nonclinical individuals (6%). DES score did not differ significantly with respect to epilepsy-related variables. Neither the frequency nor severity of PNES was significantly associated with the DES score. Our findings confirm some associations between PNES and dissociation in patients with coexisting epilepsy and PNES. The DES could be helpful in determining the tendency to have PNES in patients with epilepsy.

Psychogenic non-epileptic seizures--definition, etiology, treatment and prognostic issues: a critical review

In this review we systematically assess our currently available knowledge about psychogenic non-epileptic seizures (PNES) with an emphasis on the psychological mechanisms that underlie PNES, possibilities for psychological treatment as well as prognosis. Relevant studies were identified by searching the electronic databases. Case reports were not considered. 93 papers were identified; 65 of which were studies. An open non-randomized design, comparing patients with PNES to patients with epilepsy is the dominant design. A working definition for PNES is proposed. With respect to psychological etiology, a heterogeneous set of factors have been identified. Not all factors have a similar impact, though. On the basis of this review we propose a model with several factors that may interact in both the development and prolongation of PNES. These factors involve psychological etiology, vulnerability, shaping, as well as triggering and prolongation factors. A necessary first step of intervention in patients with PNES seems to be explaining the diagnosis with care. Although the evidence for the efficacy of additional treatment strategies is limited, variants of cognitive (behavioural) therapy showed to be the preferred type of treatment for most patients. The exact choice of treatment should be based on individual differences in the underlying factors. Outcome can be measured in terms of seizure occurrence (frequency, severity), but other measures might be of greater importance for the patient. Prognosis is unclear but studies consistently report that 1/3rd to 1/4th of the patients become chronic.

Depression and symptoms affect quality of life in psychogenic nonepileptic seizures

BACKGROUND

In patients with active epilepsy, adverse medication effects and severity of depression are correlated with health-related quality of life, but seizure frequency is not. We sought to examine if the same pattern exists in patients with psychogenic nonepileptic seizures (PNES).

METHODS

We administered seizure calendars, quality of life (QOL) scales, depression scales, and symptom checklists to 49 patients with video EEG-confirmed PNES. Data analysis consisted of performing Pearson correlation coefficients, scatter plots, and t tests.

RESULTS

Depression and symptom scores significantly increased as health-related QOL scores decreased (partial correlation coefficient r = -0.73 for both comparisons), whereas seizure count was nonsignificant (partial correlation coefficient r = -0.19).

CONCLUSIONS

As is seen in epilepsy, patients with psychogenic nonepileptic seizures demonstrate that higher depressive symptoms and somatic symptoms are independently related to worsening quality of life (QOL); however, seizure frequency is not. Seizure frequency is an important focus in patient care and treatment trials. The findings underscore the importance of, along with seizure counts, also examining QOL, depression, and somatic symptoms in patients with seizures.

Cognitive behavioral therapy for psychogenic nonepileptic seizures

Treatment trials for psychogenic nonepileptic seizures (PNES) are few, despite the high prevalence and disabling nature of the disorder. We evaluated the effect of cognitive behavioral therapy (CBT) on reduction of PNES. Secondary measures included psychiatric symptom scales and psychosocial variables. We conducted a prospective clinical trial assessing the frequency of PNES in outpatients treated using a CBT for PNES manual. Subjects diagnosed with video/EEG-confirmed PNES were treated with CBT for PNES conducted in 12 weekly sessions. Seizure calendars were charted prospectively. Twenty-one subjects enrolled, and 17 (81%) completed the CBT intervention. Eleven of the 17 completers reported no seizures by their final CBT session. Mean scores on scales of depression, anxiety, somatic symptoms, quality of life, and psychosocial functioning showed improvement from baseline to final session. CBT for PNES reduced the number of PNES and improved psychiatric symptoms, psychosocial functioning, and quality of life.

Psychiatric symptoms and dissociation in conversion, somatization and dissociative disorders

OBJECTIVE

Conversion, dissociation and somatization are historically related in the long established concept of hysteria. Somewhere along the way they were separated due to the Cartesian dualistic view. The aim of the present study was to compare these pathologies and investigate whether symptoms of these pathologies overlap in their clinical appearance in a Portuguese sample.

METHOD

Twenty-six patients with conversion disorder, 38 with dissociative disorders, 40 with somatization disorder, and a comparison group of 46 patients having other psychiatric disorders answered questions about dissociation (Dissociative Experiences Scale), somatoform dissociation (Somatoform Dissociation Questionnaire), and psychopathological symptoms (Brief Symptom Inventory).

RESULTS

Dissociative and somatoform symptoms were significantly more frequent in dissociative and conversion disorder than in somatization disorder and controls. There were no significant differences between dissociative and conversion patients.

CONCLUSIONS

Conversion disorder is closely related to dissociative disorders. These results support the ICD-10 categorization of conversion disorder among dissociative disorders and the hypothesis of analogous psychopathological processes in conversion and dissociative disorders versus somatization disorder.

Comparison of two types of dissociation in epileptic and nonepileptic seizures

Dissociation is regarded as a possible psychological mechanism in nonepileptic seizures (NES), although existing evidence for this is equivocal. It has been suggested that the contradictory findings in this area reflect the use of measures that conflate qualitatively distinct types of dissociation, and provide inadequate coverage of the aspects of dissociation most closely related to NES. The study described here addressed this shortcoming by measuring the occurrence of two different types of dissociation, "detachment" (measured using the Cambridge Depersonalisation Scale) and "compartmentalization" (measured using the Somatoform Dissociation Questionnaire), in patients with NES (n=32) and epilepsy controls (n=37). As predicted, patients with NES scored significantly higher on the measure of compartmentalization only; contrary to prediction, however, this difference was no longer significant when anxiety and depression were controlled for. The conceptual and methodological implications of the study are discussed.

Demographic and mental health factors associated with pathological dissociation in a Portuguese sample

Pathological dissociation has been extensively studied in many countries; however, little is known about it in Portugal. This research examined the role of demographic variables and mental health on dissociation in Portugal. We assessed 505 participants from 6 samples consisting of dissociative patients (n = 37), conversive patients (n = 26), somaticizing patients (n = 59), posttraumatic stress disorder patients (n = 50), other psychiatric patients (n = 174), and nonclinical subjects (n = 159). Dissociation was measured by Portuguese versions of the Dissociative Experiences Scale and Somatoform Dissociation Questionnaire; the LEAD procedure and subscales of the Brief Symptom Inventory indicated mental health. Pathological psychological dissociation was significantly more frequent in women, in the youngest of the participants, and in those with less education. Multiple logistic regression revealed that psychoticism, paranoid ideation, and depression symptoms made both men and women more vulnerable to psychological dissociation. Furthermore, psychological dissociation was more probable in men having symptoms of obsession and paranoid ideation and in women having symptoms of psychoticism and paranoid ideation. Pathological somatoform dissociation was significantly more probable in women with less education. Moreover, somatoform dissociation was more likely in women with somatization symptoms and more likely in men with symptoms of somatization and psychoticism. Even though significant associations were found, causal relations could not be established because the study was cross-sectional.

Conceptualization and treatment of psychogenic non-epileptic seizures

Psychogenic non-epileptic seizures (PNES) frequently present co-morbidly with a range of somatic and psychiatric conditions. This review discusses the relationship between PNES, a number of co-morbid psychiatric symptoms, early attachment trauma, and disruption of neurological development. We suggest that it may be clinically useful to understand PNES with reference to three patterns of co-morbidity and trauma history. In the first group, PNES are one symptom of a response to severe, chronic trauma and invalidation in attachment relationships, or a response to a recent event that overwhelms an emotion regulation system shaped by attachment trauma. For a second group, PNES occur in the context of ongoing interruptions to self and memory with or without a history of attachment trauma. For a third group, PNES occur in the absence of extensive co-morbidity and apparent trauma, primarily as a panic reaction, in a population with under-developed emotion regulation skills. Treatment approaches consistent with these conceptualizations are suggested.

Should conversion disorder be reclassified as a dissociative disorder in DSM V?

Pseudoneurological symptoms (i.e., conversion disorder), historically subsumed within the "hysteria" concept alongside phenomena such as psychogenic amnesia and multiple personality disorder, have been classified as somatoform disorders since DSM-III. Since then, there have been repeated calls to reclassify conversion disorder with the dissociative disorders, as in ICD-10. The authors review issues such as the high correlations between pseudoneurological and dissociative symptoms, the high rates of trauma reported for both groups, and the position that these phenomena share underlying processes. Although reintegrating pseudoneurological symptoms with the dissociative disorders is not without complications, there is a strong case for such a reclassification.

The idiosyncratic aspects of the epilepsy of Fyodor Dostoevsky

The goal of this article is to review the idiosyncratic aspects of the epilepsy of Fyodor Dostoevsky, one of the greatest writers of all time. The onset of his seizures is controversial, with some evidence pointing to his childhood and other reports that would place the onset in his teens or his twenties. His life in prison in Siberia and then in the Russian army is reviewed. His lifestyle included many factors that exacerbated his epilepsy, especially stress and sleep deprivation. His compulsion for gambling played an important role in producing great stress in his life, as he tried to reverse his poverty in the casinos. The most idiosyncratic aspect of his epilepsy was his so-called ecstatic aura. The etiology of his seizures was probably inherited as revealed by the seizures of his father and the status epilepticus and death of his young son. This great writer died from lung hemorrhages in 1891. Discussed in this review is that he did not likely have an aura of ecstasy; only a few such possible cases can be found in the world literature. For those few cases, evidence from electrical self-stimulation studies in animals and humans, investigating "pleasure centers," can be found to involve the limbic system, especially the septal nucleus. Data from the human amygdala provide evidence why almost all auras are, in fact, unpleasant and not pleasant. A review of recent data on the risks to offspring of epileptic fathers confirms that the etiology of Dostoevsky's epilepsy was probably inherited and that he probably had an idiopathic generalized epilepsy with minor involvement of the temporal lobe. A relationship is seen between his severe obsession with gambling and his epilepsy. Finally, Fyodor Dostoevsky is an excellent example of the "temporal lobe personality."

The Brief Symptom Inventory (BSI) as a screening tool for psychological disorders in patients with epilepsy and mild intellectual disabilities in residential care

This study examines the usefulness of the Brief Symptom Inventory (BSI) as a screening tool for psychological disorders in patients with epilepsy and mild intellectual disabilities. Participants were 91 residents of the Bethel Institute, Bielefeld, Germany. Cronbach's alpha was revealed to be sufficient for the composite score Global Severity Index (GSI) (0.95) and for most of the subscales (0.64-0.80). Compared with normative data, residents with epilepsy scored slightly higher on all BSI scales. Only the subscale Paranoid Ideation was especially elevated, a finding of heuristic value. Subgroups of residents with past psychiatric morbidity, on current psychotropic medication, with poor seizure control, and more epilepsy-related problems either tended toward or demonstrated higher GSI scores. These results indicate the validity of the questionnaire with the GSI as a global indicator of possible psychopathology. BSI subscales seemed to reflect predominantly the amount of emotional distress, but their potential to identify specific clinical syndromes remained unclear.

Trauma and dissociation in conversion disorder and chronic pelvic pain

OBJECTIVE

The purpose of this study was to: a) assess the link between sexual and/or physical abuse and dissociation in conversion disorder and chronic pelvic pain patients; and b) assess whether this effect is independent of level of general psychopathology.

METHOD

This report examines data from four separate samples. Fifty-two patients with chronic pelvic pain, 61 patients with non-epileptic seizures, and two samples of patients (102 and 54) with predominantly motor or sensory types of conversion disorder were studied.

RESULTS

Using point-biserial correlations no compelling evidence for a consistent and positive association of sexual and/or physical abuse with dissociation was found. After statistically controlling for level of psychopathology using multiple regression analyses, in most of the cases the association of abuse with dissociation was no longer statistically significant. Only physical abuse predicted level of somatoform dissociation over and above level of psychopathology.

CONCLUSION

In future clinical studies of dissociation in patients with conversion disorder and chronic pelvic pain more complex models may be needed with less exclusive reliance on historical antecedents such as childhood abuse and more emphasis on recent potentially traumatizing experiences or co-morbid psychiatric disorders.

Frequency of panic symptoms in psychogenic nonepileptic seizures

This study investigates the frequency of symptoms of panic attack in a sample of adults (n = 18) and adolescents (n = 21) who were evaluated for intractable seizure disorder and diagnosed with psychogenic nonepileptic seizures (PNES). Medical records were retrospectively reviewed for symptoms associated with their typical seizure events as documented by the attending epileptologist. Adolescents, as a group, reported significantly more symptoms of panic attack than adults. Three adolescents met the full criteria for a panic attack, while no adults met these criteria. In addition, while numerous adults endorsed no panic symptoms associated with their PNES episodes, all adolescents endorsed at least one symptom. Implications of results are discussed in terms of the diagnosis and treatment of PNES in the different age groups.

Can memories kindle nonconvulsive behavioral seizures in humans? Case report exemplifying the "limbic psychotic trigger reaction"

We present three hypotheses-(1) the limbic psychotic trigger reaction (LPTR) is a form of nonconvulsive behavioral seizures (NCBS), (2) kindling may occur in the LPTR, and (3) kindling may occur with memory stimuli-and report a case that may exemplify a LPTR kindled by memory and triggered by light and smell. The LPTR has a primate model, in which NCBS are kindled by intermittent exposure to actual subthreshold stimuli. In humans, we propose that such triggering stimuli can be revived by memory alone. Thus, individualized stimuli can trigger partial limbic seizures or seizure-like bizarre episodes with a transient loss of frontal control functions. We present a case of paroxysmal episodes of out-of-character, bizarre, unplanned nonvoluntary acts that occurred with flat affect and without drive motivation (e.g., "fire setting"). Implicated is a transient state of limbic "paleo-consciousness" with preserved memory, autonomic arousal, and first-time brief psychosis (e.g., olfactory, visual hallucinations and depersonalization with olfactory attributes). As in kindled primates, LPTR patients do not show a consistent pattern of morphological brain abnormality; half have had an abnormal electroencephalogram, computed tomography scan, or magnetic resonance image at some time during their lives, and half (including the new patient) have had closed head injuries.

An Evaluation of Cognitive Behavioral Therapy as a Treatment for Dissociative Seizures

OBJECTIVE

To evaluate in an open trial the effectiveness of cognitive behavioral therapy as a treatment of adults with dissociative seizures (i.e., "pseudoseizures").

BACKGROUND

Although suggestions have been made concerning the management of patients with dissociative seizures, no studies have previously evaluated the systematic use of cognitive behavioral therapy in the treatment of this disorder.

METHOD

Twenty patients diagnosed with dissociative seizures were offered treatment comprising 12 sessions of cognitive behavioral therapy. Principal outcome measures were dissociative seizure frequency and psychosocial functioning, including improvement in employment status and mood. Measures were administered before treatment, at the end of treatment, and at a 6-month follow-up.

RESULTS

Treatment was completed by 16 patients (questionnaire measures were not available for 4 patients who discontinued treatment). Following treatment, there was a highly significant reduction in seizure frequency and an improvement in self-rated psychosocial functioning. These improvements were maintained at the 6-month follow-up. There was also a tendency for patients to have improved their employment status between the start of treatment and the 6-month follow-up period.

CONCLUSIONS

In this open prospective trial, cognitive behavioral therapy was associated with a reduction in dissociative seizure frequency and an improvement in psychosocial functioning in adults with dissociative seizures.

Seizure disorders, depression, and health-related quality of life

Disease and mood states are important determinants of quality of life (QOL). Low QOL, due to mood states, can be expected especially in psychiatric disorders such as depression. However, patients with seizure disorders may be even more affected because of the combined burden of physical episodes, psychiatric comorbidities, and psychosocial factors (e.g., stigma). In this study, we compare the quality of life in seizure disorders and clinical depression. Based on our earlier findings, we hypothesize that epilepsy patients fare better than patients with psychogenic, nonepileptic seizures (PNES), and we speculate that QOL in PNES is also lower relative to clinical depression. We estimate the relationships between type of seizures (epilepsy vs PNES), depression, and QOL (SF-36) using multiple regression, and we compare the SF-36 scores of patients with epilepsy and PNES (n=194) with the normative data for clinical depression using one-sample t tests. Our findings indicate that depression contributes to the poor QOL in both epilepsy and PNES, but the patients with PNES, even those without depression, have worse QOL compared with both the epilepsy patients and the depression norms. We conclude that evaluating and treating mood states is as important as treating PNES itself when caring for patients with PNES, and it might be the first step toward improving their QOL.

Phenomenology and psychiatric origin of psychogenic nonepileptic seizures

INTRODUCTION Psychogenic nonepileptic seizure (PNES) is a sudden change in a person's behavior, perception, thinking, or feeling that is usually time limited and resembles, or is mistaken for, epilepsy but does not have the characteristic electroencephalographic (EEG) changes that accompanies a true epileptic seizure [1]. It is considered that PNES is a somatic manifestation of mental distress, in response to a psychological conflict or other Stressors [2]. A wide spectrum of clinical presentation includes syncope, generalized tonic-clonic seizure, simple and complex partial seizure, myoclonic seizure, frontal lobe seizures and status epilepticus [3]. Coexistence of epilepsy and PNES is seen in approximately 9% of cases [5]. Between 25-30% of patients referred to tertiary centers and initially diagnosed as refractory epilepsy were on further examination diagnosed as PNES [6,7]. In DSM-IV [12] PNES are usually categorized under conversion disorder with seizures or convulsions. However, psychiatric basis of PNES may be anxiousness (panic attack), somatization or factitious disorder, simulation, dissociative disorders and psychosis [1]. AIM The aim of the study was to establish clinical phenomenology and EEG characteristics as well as basic psychiatric disorder in patients with PNES. METHOD In a retrospective study covering the period from January 1st 1999 till April 31 st 2003, 24 patients (22 female, 2 male) treated at the Institute of Neurology in Belgrade were analyzed. PNES were defined as sudden change in behavior incoherent with epileptiform activity registered on EEG. Possible PNES were determined on the basis of history data and clinical examination during the attack but definitive confirmation was established only by the finding of no ictal EEG changes during typical seizure of each patient. Patients with coexisting epilepsy were included in the study, too. At least two standard EEG (range 2-6, median 4) were performed at the beginning of diagnostic evaluation. Demographic data, clinical presentation (apparent loss of consciousness, type of convulsion and associated clinical signs) and placebo-induced seizures (administration of saline near the cubital vein) with EEG or video-EEG monitoring were analyzed. Basic psychiatric disorder was classified according to DSM IV classification criteria. RESULTS Duration of PNES was 4.7 years (range from 2 months to 30 years). The time from onset to the diagnosis of PNES was 4.5 years. Epilepsy comorbidity was diagnosed in 9 patients (37.5%). The average time of use of antiepileptic drugs (AED) in the group of isolated PNES was 2.4 years and 20% of patients were treated with two or more AED. The vast majority of patients presented with bilateral convulsions (54.16%) with apparent loss of consciousness found in 91.6% of cases. Ictal iwury (16.7%), tongue bite (4.2%) and premonition of the seizure (17.4%) were uncommon. Variability in clinical presentation of seizures was found in over half of patients (57%). Psychological trigger could be determined in over 60% of patients. EEG findings in a group with isolated PNES suggesting the existence of epileptiform activity was found in one case. EEG monitoring of placebo-induced seizure was performed in 20 patients, of whom 19 (95%) showed typical habitual attack with no electroclinical correlate. In 70% of cases conversion disorder DSM-IV criteria were fulfilled. Somatization disorder and undifferentiated somatoform disorder were found in 3 patients. The diagnosis of factitious disorder was made in one case and only two patients were undiagnosed according to DSM-IV. DISCUSSION Average delay from onset to diagnosis of PNES in larger studies was estimated to be approximately 7 years [8]. Even though diagnostic delay in our study was shorter, organizational reasons for this could not be found. Longer duration of a typical attack (compared to the epileptic seizure), apparent loss of consciousness, bilateral convulsion behavior and significant clinical variability in absence of typical epileptic elements such as tongue bite and ictal iwury could be the main clinical manifestation of PNES. We found rare interictal abnormalities (6.7%) in the group with isolated PNES and significant percentage (77.7%) in patients with coexisting epilepsy which is coherent with other reports [8]. The latest could lead to prolonged delay in appropriate diagnosis and suitable treatment. Clear psychological trigger wasn't noted in whole group of patients (61 %). This, however, is not unusual since PNES represents a chronic disorder with repeated triggering that could lead to less significant role of the same psychological trigger in developed PNES. Even insufficiently resolved in ethical terms, placebo-induced procedure was of huge sensitivity. In clinical practice conversion disorder is hard to differ from malingering or implementation of secondary gain. One could make the conclusion only on the basis of detailed and careful estimation of the symptoms developing context Conversion disorder is more prevalent among women (from 2:1 to 10:1) [4, 13] but modest percentage of affected men could be explained only by limited sample in this study. CONCLUSION PNES is often replaced with epilepsy and in number of cases clinical differentiation is not easy. One should be acquainted with clinical presentation of PNES as well as its psychiatric origin in order to adequately recognize and treat the disorder.

Somatization, dissociation and general psychopathology in patients with psychogenic non-epileptic seizures

The etiology of psychogenic non-epileptic seizures (PNES) remains uncertain. Previous studies have shown that PNES patients are characterized by high levels of somatization, dissociation and general psychopathology but a correlation of measures of these features and PNES severity or outcome has never been demonstrated, although this would strengthen a possible etiological link. This study measured somatization (Screening Test for Somatoform Symptoms-2), dissociation (Dissociative Experience Scale, DES), and general psychopathology (Symptom Checklist-90-Revised, SCL-90) in 98 patients with PNES and 63 patients with epilepsy. All mean scores were raised in the PNES compared to the epilepsy group. However, only measures of somatization and general psychopathology discriminated between patients with PNES and epilepsy in a logistic regression model (even when patient gender was controlled for). In PNES patients, high somatization scores correlated with poor outcome and greater seizure severity even after correction was made for dissociation and psychopathology. Dissociation and psychopathology scores were not independently associated with outcome or severity. The results suggest that, as a group, patients with PNES are best characterized by their tendency to express psychosocial distress by producing unexplained somatic symptoms which are brought to medical attention. Although dissociation may be relevant in some individuals it does not appear to be an independent factor across the whole PNES patient group.

Non-epileptic seizures: patients' understanding and reaction to the diagnosis and impact on outcome

RATIONALE

The study aim was to assess patients' understanding of and reaction to a diagnosis of non-epileptic attack disorder and to explore whether these factors contribute to outcome.

METHOD

Eighty-four patients diagnosed with non-epileptic attack disorder participated in the study. Participants answered questions about their seizures and understanding and reaction to the diagnosis. Data were collected by semi-structured telephone interview. Questionnaires were sent to the patients' general practitioners (GPs) to gather information regarding the patient's seizure status, prescription of anti-epileptic drugs and opinion regarding the diagnosis.

RESULTS

At the time of follow-up, a third of participants reported being seizure free. A total of 63% did not have a good understanding of the diagnosis, most were unclear about the precipitating factors and the most common reaction to the diagnosis was confusion. Many reported a negative impact of NES on everyday life. Sixty-five percent reported receiving psychological follow-up but the number of sessions attended was few (median 2). There was evidence that the reaction to the diagnosis contributed to the outcome in particular an angry outcome was associated with a poor prognosis. Ten GPs did not agree with the diagnosis.

CONCLUSION

Patients understanding and reactions to a diagnosis of non-epileptic attacks are important factors that should contribute to the development of more tailored treatment approaches.