Non-Epileptic Seizures (NES) are predicted by depressive and dissociative symptoms

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.

Seizures and pseudoseizures: The great divide

Patients who display the neurological phenomena variously referred to as pseudoseizures, dissociative seizures, or psychogenic non-epileptic seizures present an important problem in the treatment of epilepsy. Their convulsive or non-convulsive episodes show no epileptiform activity on electroencephalography but are distressing and debilitating to patients so afflicted, and can be difficult to distinguish from classical epilepsy. It is important to make this distinction, as the treatment for pseudoseizures is typically cognitive behavioral therapy rather than anticonvulsant medication. This review describes the clinical differences in the signs and symptoms of patients with pseudoseizures vs classical epileptic seizures, as well as the underlying mechanisms triggering pseudoseizures, and the outcomes achieved with the treatment paradigms currently available for them.

[Clinical presentation, co-occurrence and suicidality in psychiatric emergency patients with psychogenic non-epileptic seizures]

INTRODUCTION

Non-epileptic psychogenic seizures (PNES) are a common condition but little studied in psychiatry. Our study is the first Moroccan of this topic. Our aim was to describe their clinical presentation, comorbidities and suicidality.

METHOD

It was a one-year recruitment study conducted in the Department of Psychiatry at the University Hospital of Fez. We collected socio-demographic data. Psychometric evaluation used the MINI criteria for different psychiatric disorders, personality disorders and suicidality, the Hamilton anxiety scale, the Beck depression scale and the Childhood Trauma Questionnaire.

RESULTS

Thirty-two patients were included, the majority of whom were female with a low economic level (89 %). The average age of onset average was 23.97 years. The generalized form represented 71.9 % of cases with a triggering factor present in 46 %. The duration of the seizures average was 23.47minutes, and 37.5 % of the patients had at least one attack per day. Among patients, 68.8 % had comorbidity: major depressive disorder MDD (46 %) and post-traumatic stress disorder PTSD (18.6 %). Suicide risk was rated as moderate or severe in 12.5 % of patients, and 40.62 % had a previous suicide attempt. A personality disorder was present in 18.8 % of cases. Finally, a history of child abuse was found in 59.4 % of patients and was correlated to PNES age of onset and co-occurrence depression.

CONCLUSION

We found several similarities with previous studies in terms of clinical description and co-occurrences. However, our sample is characterized by more prolonged and more frequent seizures and a higher rate of suicidality.

Anxiety disorders in predominantly African American and Caribbean American adults with intractable epilepsy: The role of perceived epilepsy stigma

INTRODUCTION

Anxiety disproportionately affects people with epilepsy (PWE) and leads to poor outcomes. Yet, risk factors are not well understood especially among underserved groups. This cross-sectional study aimed to identify epilepsy-specific predictors of anxiety disorders in predominantly African American and Caribbean American PWE.

MATERIALS AND METHODS

The prevalence of anxiety disorders was established via diagnostic interview (Mini-International Neuropsychiatric Interview (MINI)). We identified the extent to which aspects of seizure burden (seizure frequency, seizure severity, convulsive vs. nonconvulsive seizures), seizure worry, and perceived epilepsy stigma were associated with anxiety disorder diagnosis. Finally, logistic regression assessed the overall and independent contributions of significant risk factors.

RESULTS

There were 60 participants (62% women, 52% African American, 27% Caribbean American, 20% Hispanic/Latino) with an average of 2 seizures per month. Nearly half of the sample (43%) had ≥1 anxiety disorder, with 62% of affected individuals qualifying for agoraphobia. Those with anxiety disorders tended to have convulsive seizures (p = 0.037) and endorsed greater seizure worry (p = 0.012), more general symptoms of anxiety (p = 0.005), and worse perceived epilepsy stigma (p = 0.003). Logistic regression accounted for 28% to 37.6% of the variance in anxiety disorder diagnostic status and correctly classified 73% of cases; however, only perceived epilepsy stigma made a unique contribution.

CONCLUSIONS

Anxiety disorders were prevalent in these predominantly African American and Caribbean American PWE. Epilepsy-specific risk factors included convulsive seizures, seizure worry, and perceived epilepsy stigma. Interventions aimed at treating anxiety disorders in diverse PWE may especially benefit from targeting stigma beliefs.

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.

Anxiety and depressive disorders in people with epilepsy: A meta-analysis

OBJECTIVE

Comorbid anxiety and depressive disorders in people with epilepsy (PWE) are highly prevalent and associated with various adverse outcomes. However, the prevalence of anxiety disorders in PWE across studies is highly variable. Our aim was to estimate the prevalence and moderating factors of anxiety and depressive disorders in PWE.

METHODS

Following prospective registration (PROSPERO; CRD42015027101), electronic databases were searched for studies that reported the prevalence of both anxiety and depressive disorders in samples of PWE up until July 2016. Data extracted included the prevalence of anxiety and depressive disorders, and moderators of interest (e.g., method of diagnosis, prevalence of drug-resistant epilepsy). Meta-analysis of the overall pooled prevalence of anxiety and depressive disorders was conducted.

RESULTS

The search yielded 8,636 unique articles, with 27 studies meeting final inclusion criteria (3,221 PWE). The pooled prevalence of anxiety and depressive disorders was 20.2% (95% confidence interval [CI] 15.3-26.0%) and 22.9% (95% CI 18.2-28.4%), respectively. Method of diagnosis significantly moderated anxiety disorder prevalence (Q statistic with one degree of freedom [Q₁ ] = 36.29, p < 0.0001); the prevalence of anxiety disorders based on unstructured clinician assessment was 8.1% (95% CI 5.7-11.4%), compared to a prevalence of 27.3% (95% CI 22.1-33.3%) based on a structured clinical interview. There were no significant moderators of depressive disorder diagnosis.

SIGNIFICANCE

Findings suggest the prevalence of anxiety and depressive disorders in PWE are equivalent, and variability in prevalence of anxiety disorders across studies can be attributed partly to the method of diagnosis. These findings also challenge widely held assumptions that psychiatric comorbidity is more common in people with drug-resistant epilepsy. Future research should aim to improve the detection and management of these comorbidities in PWE, particularly anxiety disorders, which have remained relatively neglected.

Explicit Facial Emotion Processing in Patients With Dissociative Seizures

OBJECTIVE

There have, as yet, been few experimental studies of explicit facial affect recognition in patients with dissociative seizures (DS). The aim of the study was to examine explicit recognition and physiological responses to facial expressions in this group, relative to healthy controls.

METHODS

Forty patients with DS and 43 controls completed a computerized test of facial affect recognition, including five basic expressions (happiness, anger, disgust, fear, neutral). Recognition accuracy, emotional intensity judgements, and skin conductance levels and responses were dependent measures. Analyses controlled for a range of potentially confounding variables, including anxiety, depression, and medication effects.

RESULTS

The DS group was less accurate at identifying facial expressions than controls (p = .005, ηp = 0.10). No group difference emerged for intensity judgements (p = .72, ηp = 0.002). Mean skin conductance levels were higher in the DS group relative to controls (p = .046, ηp = 0.053). However, a subgroup of DS patients showed attenuated skin conductance responses to the facial stimuli, compared with controls (p = .015, ηp = 0.18). These differences could not be accounted for by possible confounding variables. Recognition accuracy for neutral faces correlated negatively with trauma scores (r = -0.486, p = .002) and abandonment concerns (r = -0.493, p = .002) in the DS group.

CONCLUSIONS

Patients with DS showed reduced recognition accuracy for facial affect, despite accurately perceiving its intensity. Elevated autonomic arousal may characterize patients with DS in general, alongside reduced phasic autonomic responses to facial expressions in some patients with the disorder.

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.

Dissociation and functional neurologic disorders

Dissociation has been cited as a possible psychologic mechanism underpinning functional neurologic disorders (FND) since the 19th century. Since that time, changes in psychiatric classification have created confusion about what the term dissociation actually means. The available evidence suggests that it now refers to at least two qualitatively distinct types of phenomena: detachment (an altered state of consciousness characterized by a sense of separation from the self or world) and compartmentalization (a reversible loss of voluntary control over apparently intact processes and functions), as well as their underlying mechanisms. This chapter considers some of the problems with conflating these phenomena under a single heading as well as the relationship between detachment, compartmentalization, and FND. It is argued that FNDs are fundamentally compartmentalization disorders, but that detachment is often part of the clinical picture and may contribute to the development and maintenance of functional symptoms in many cases. By this view, understanding compartmentalization requires an appreciation of the mechanisms involved in controlling and accessing mental processes and contents. Two possible mechanisms in this regard are described and the evidence for these is considered, followed by a discussion of clinical and empiric implications.

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.

Comparison of common data elements from the Managing Epilepsy Well (MEW) Network integrated database and a well-characterized sample with nonepileptic seizures

INTRODUCTION

Epilepsy and psychogenic nonepileptic seizures (PNES) are both chronic illnesses characterized by similar and overlapping clinical features. A limited number of studies comparing people with epilepsy (PWE) and patients with PNES that address determinants of health outcomes exist. We conducted an analysis using a well-characterized sample of people with PNES and the Managing Epilepsy Well (MEW) Network integrated data, comparing descriptive data on samples with epilepsy and with documented PNES. Based on the pooled data, we hypothesized that people with PNES would have worse QOL and higher depression severity than PWE.

MATERIAL AND METHODS

We used data from the MEW Network integrated database involving select epilepsy self-management studies comprising 182 PWE and 305 individuals with documented PNES from the Rhode Island Hospital Neuropsychiatry and Behavioral Neurology Clinic. We conducted a matched, case-control study assessing descriptive comparisons on 16 common data elements that included gender, age, ethnicity, race, education, employment, income, household composition, relationship status, age at seizure onset, frequency of seizures, seizure type, health status, healthy days, quality of life, and depression. Standardized rating scales for depression and quality of life were used.

RESULTS

Median seizure frequency in the last 30days for PWE was 1, compared to 15 for patients with PNES (p<0.05). People with epilepsy had a QOLIE-10 mean score of 3.00 (SD: 0.91) compared to 3.54 (0.88) (p<0.01) for patients with PNES. Depression severity was moderate to severe in 7.7% of PWE compared to 34.1% (p<0.05) of patients with PNES.

DISCUSSION

People with epilepsy in selected MEW Network programs are fairly well educated, mostly women, with few minorities and low monthly seizure rates. Those with PNES, however, have higher levels of not working/on disability and had more frequent seizures, higher depression severity, and worse QOL. These differences were present despite demographics that are largely similar in both groups, illustrating that other determinants of illness may influence PNES.

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.

Emotional dysregulation, alexithymia, and attachment in psychogenic nonepileptic seizures

OBJECTIVES

Psychogenic nonepileptic seizures (PNESs) are poorly understood and difficult to treat. Research and theory suggest that problems with recognizing, acknowledging, and regulating emotional states (i.e., emotional dysregulation) may contribute to the development and maintenance of PNESs. However, there is a lack of well-controlled studies using dedicated measures of emotional regulation with patients with PNESs. The current study sought to address this gap.

METHODS

Forty-three patients with PNESs and 24 with epilepsy completed a postal survey comprising measures of emotional dysregulation (Difficulties in Emotion Regulation Scale), alexithymia (Toronto Alexithymia Scale), attachment (Relationship Scales Questionnaire), and psychopathology (Generalized Anxiety Disorder-7; Patient Health Questionnaire-9; Somatoform Dissociation Questionnaire-20). Cluster analysis was used to identify possible subgroups of patients with PNESs characterized by distinct patterns of emotional dysregulation.

RESULTS

Two clusters of patients with PNESs were identified. The first (n=11) was characterized by higher levels of psychopathology, somatization, alexithymia, and difficulties with most aspects of emotional regulation (including identifying, accepting, and describing feelings, accessing adaptive regulatory strategies, performing goal-directed behaviors, and controlling feelings and actions) compared with the group with epilepsy. The second (n=32) was characterized by relatively high somatization and depression scores but comparatively normal levels of alexithymia and emotional regulation.

CONCLUSIONS

The findings suggest that patients with PNESs can be divided into at least two meaningful subgroups characterized by distinct psychological profiles, only one of which is characterized by significant problems with emotional dysregulation. Further research is needed to determine whether the relatively normal emotional dysregulation and high somatization scores of some patients with PNESs are due to emotional avoidance or more basic problems with perceptual and behavioral control.

Subgroup classification in patients with psychogenic non-epileptic seizures

INTRODUCTION

In this open non-controlled clinical cohort study, the applicability of a theoretical model for the diagnosis of psychogenic non-epileptic seizures (PNES) was studied in order to define a general psychological profile and to specify possible subgroups.

METHODS

Forty PNES patients were assessed with a PNES "test battery" consisting of eleven psychological instruments, e.g., a trauma checklist, the global cognitive level, mental flexibility, speed of information processing, personality factors, dissociation, daily hassles and stress and coping factors.

RESULTS

The total PNES group was characterized by multiple trauma, personality vulnerability (in a lesser extent, neuropsychological vulnerabilities), no increased dissociation, many complaints about daily hassles that may trigger seizures and negative coping strategies that may contribute to prolongation of the seizures. Using factor analysis, specific subgroups were revealed: a 'psychotrauma subgroup', a 'high vulnerability somatizing subgroup' (with high and low cognitive levels) and a 'high vulnerability sensitive personality problem subgroup'.

CONCLUSION

Using a theoretical model in PNES diagnosis, PNES seem to be a symptom of distinct underlying etiological factors with different accents in the model. Hence, describing a general profile seems to conceal specific subgroups with subsequent treatment implications. This study identified three factors, representing two dimensions of the model, that are essential for subgroup classification: psychological etiology (psychotrauma or not), vulnerability, e.g., the somatization tendency, and sensitive personality problems/characteristics ('novelty seeking'). For treatment, this means that interventions could be tailored to the main underlying etiological problem. Also, further research could focus on differentiating subgroups with subsequent treatment indications and possible different prognoses.

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.

Depression and epilepsy, pain and psychogenic non-epileptic seizures: clinical and therapeutic perspectives

The clinical manifestations of depression in people with epilepsy (PWE) are pleomorphic, often associated with anxiety symptoms and anxiety disorders. The ongoing debate of whether the clinical presentation of depression in PWE is unique to this neurologic disorder is reviewed. Comorbid depression can impact the recruitment of PWE for pharmacologic trials with antiepileptic drugs (AEDs). Yet, the impact of depression on the response of the seizure disorder to pharmacotherapy with AEDs and its impact on worse adverse events may bias the interpretation of the trial findings, particularly when depressed patients are included in the AED trials. PWE have a greater suicidal risk than the general population. This risk is mediated by multiple factors, and recent data from the FDA have imputed a potential pathogenic role to all AEDs. The recognition of patients at risk is reviewed. Yet, the validity of the FDA data has been questioned, and the status of this controversial question is analyzed. As in the case of epilepsy, depression and pain syndromes have a relatively high comorbidity. The negative impact of depression on pain is reminiscent of that of depression in PWE; furthermore, the high comorbidity may be also associated with the existence of common pathogenic mechanisms. Neurologists and in particular, epileptologists establish the diagnosis of psychogenic non-epileptic seizures (PNES) in whom a comorbid depressive disorder is very often identified. The role of depression in the course of PNES and its treatment are discussed. Scarce data are available on the treatment of depression in PWE. Thus, clinicians have had to adopt data from patients with primary depressive disorders. We outline a consensus strategy on the identification and treatment of depressive disorders in adult and pediatric patients with epilepsy.

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.

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.

Conversion disorder and coexisting nonepileptic seizures in patients with refractory seizures

Nonepileptic seizures (NES) are commonly observed in patients with seizures resistant to antiepileptic drugs (AEDs). However, NES may be symptomatic of different diagnoses, in particular, conversion disorder (CD) and coexisting NES and epileptic seizures (CENES). We compared the clinical characteristics of these disorders in 219 patients with refractory seizures. The prevalence of NES was similar in children (11%) and adults (16%). In both groups, CENES represented the most frequent cause of NES (75%). In adults, CD was associated with a shorter duration of illness and normal neuroimaging and interictal EEG compared with the other groups. Patients with CD represented one-quarter of all patients with AED-resistant seizures with normal presentation during interictal investigations. In both children and adults with AED-resistant seizures, NES are frequently observed and are three times more likely to be CENES than CD.