Psychological and demographic characteristics of 368 patients with dissociative seizures: data from the CODES cohort

BACKGROUND

We examined demographic, clinical, and psychological characteristics of a large cohort (n = 368) of adults with dissociative seizures (DS) recruited to the CODES randomised controlled trial (RCT) and explored differences associated with age at onset of DS, gender, and DS semiology.

METHODS

Prior to randomisation within the CODES RCT, we collected demographic and clinical data on 368 participants. We assessed psychiatric comorbidity using the Mini-International Neuropsychiatric Interview (M.I.N.I.) and a screening measure of personality disorder and measured anxiety, depression, psychological distress, somatic symptom burden, emotional expression, functional impact of DS, avoidance behaviour, and quality of life. We undertook comparisons based on reported age at DS onset (<40 v. ⩾40), gender (male v. female), and DS semiology (predominantly hyperkinetic v. hypokinetic).

RESULTS

Our cohort was predominantly female (72%) and characterised by high levels of socio-economic deprivation. Two-thirds had predominantly hyperkinetic DS. Of the total, 69% had ⩾1 comorbid M.I.N.I. diagnosis (median number = 2), with agoraphobia being the most common concurrent diagnosis. Clinical levels of distress were reported by 86% and characteristics associated with maladaptive personality traits by 60%. Moderate-to-severe functional impairment, high levels of somatic symptoms, and impaired quality of life were also reported. Women had a younger age at DS onset than men.

CONCLUSIONS

Our study highlights the burden of psychopathology and socio-economic deprivation in a large, heterogeneous cohort of patients with DS. The lack of clear differences based on gender, DS semiology and age at onset suggests these factors do not add substantially to the heterogeneity of the cohort.

Characteristics of 698 patients with dissociative seizures: A UK multicenter study

Objective

We aimed to characterize the demographics of adults with dissociative (nonepileptic) seizures, placing emphasis on distribution of age at onset, male:female ratio, levels of deprivation, and dissociative seizure semiology.

Methods

We collected demographic and clinical data from 698 adults with dissociative seizures recruited to the screening phase of the CODES (Cognitive Behavioural Therapy vs Standardised Medical Care for Adults With Dissociative Non‐Epileptic Seizures) trial from 27 neurology/specialist epilepsy clinics in the UK. We described the cohort in terms of age, age at onset of dissociative seizures, duration of seizure disorder, level of socioeconomic deprivation, and other social and clinical demographic characteristics and their associations.

Results

In what is, to date, the largest study of adults with dissociative seizures, the overall modal age at dissociative seizure onset was 19 years; median age at onset was 28 years. Although 74% of the sample was female, importantly the male:female ratio varied with age at onset, with 77% of female but only 59% of male participants developing dissociative seizures by the age of 40 years. The frequency of self‐reported previous epilepsy was 27%; nearly half of these epilepsy diagnoses were retrospectively considered erroneous by clinicians. Patients with predominantly hyperkinetic dissociative seizures had a shorter disorder duration prior to diagnosis in this study than patients with hypokinetic seizures (P < .001); dissociative seizure type was not associated with gender. Predominantly hyperkinetic seizures were most commonly seen in patients with symptom onset in their late teens. Thirty percent of the sample reported taking antiepileptic drugs; this was more common in men. More than 50% of the sample lived in areas characterized by the highest levels of deprivation, and more than two‐thirds were unemployed.

Significance

Females with dissociative seizures were more common at all ages, whereas the proportion of males increased with age at onset. This disorder was associated with socioeconomic deprivation. Those with hypokinetic dissociative seizures may be at risk for delayed diagnosis and treatment.

Implicit attentional bias for facial emotion in dissociative seizures: Additional evidence

This study sought to extend knowledge about the previously reported preconscious attentional bias (AB) for facial emotion in patients with dissociative seizures (DS) by exploring whether the finding could be replicated, while controlling for concurrent anxiety, depression, and potentially relevant cognitive impairments. Patients diagnosed with DS (n=38) were compared with healthy controls (n=43) on a pictorial emotional Stroop test, in which backwardly masked emotional faces (angry, happy, neutral) were processed implicitly. The group with DS displayed a significantly greater AB to facial emotion relative to controls; however, the bias was not specific to negative or positive emotions. The group effect could not be explained by performance on standardized cognitive tests or self-reported depression/anxiety. The study provides additional evidence of a disproportionate and automatic allocation of attention to facial affect in patients with DS, including both positive and negative facial expressions. Such a tendency could act as a predisposing factor for developing DS initially, or may contribute to triggering individuals' seizures on an ongoing basis. Psychological interventions such as Cognitive Behavioral Therapy (CBT) or AB modification might be suitable approaches to target this bias in clinical practice.

Autonomic and subjective responsivity to emotional images in people with dissociative seizures

People with dissociative seizures (DS) report a range of difficulties in emotional functioning and exhibit altered responding to emotional facial expressions in experimental tasks. We extended this research by investigating subjective and autonomic reactivity (ratings of emotional valence, arousal and skin conductance responses [SCRs]) to general emotional images in 39 people with DS relative to 42 healthy control participants, whilst controlling for anxiety, depression, cognitive functioning and, where relevant, medication use. It was predicted that greater subjective negativity and arousal and increased SCRs in response to the affective pictures would be observed in the DS group. The DS group as a whole did not differ from controls in their subjective responses of valence and arousal. However, SCR amplitudes were greater in ‘autonomic responders’ with DS relative to ‘autonomic responders’ in the control group. A positive correlation was also observed between SCRs for highly arousing negative pictures and self‐reported ictal autonomic arousal, in DS ‘autonomic responders’. In the DS subgroup of autonomic ‘non‐responders’, differences in subjective responses were observed for some conditions, compared to control ‘non‐responders’. The findings indicate unaffected subjective responses to emotional images in people with DS overall. However, within the group of people with DS, there may be subgroups characterized by differences in emotional responding. One subgroup (i.e., ‘autonomic responders’) exhibit heightened autonomic responses but intact subjective emotional experience, whilst another subgroup (i.e., ‘autonomic non‐responders’) seem to experience greater subjective negativity and arousal for some emotional stimuli, despite less frequent autonomic reactions. The current results suggest that therapeutic interventions targeting awareness and regulation of physiological arousal and subjective emotional experience could be of value in some people with this disorder.

COgnitive behavioural therapy versus standardised medical care for adults with Dissociative non-Epileptic Seizures (CODES): statistical and economic analysis plan for a randomised controlled trial

Background

Dissociative seizures (DSs), also called psychogenic non-epileptic seizures, are a distressing and disabling problem for many patients in neurological settings with high and often unnecessary economic costs. The COgnitive behavioural therapy versus standardised medical care for adults with Dissociative non-Epileptic Seizures (CODES) trial is an evaluation of a specifically tailored psychological intervention with the aims of reducing seizure frequency and severity and improving psychological well-being in adults with DS. The aim of this paper is to report in detail the quantitative and economic analysis plan for the CODES trial, as agreed by the trial steering committee.

Methods

The CODES trial is a multicentre, pragmatic, parallel group, randomised controlled trial performed to evaluate the clinical effectiveness and cost-effectiveness of 13 sessions of cognitive behavioural therapy (CBT) plus standardised medical care (SMC) compared with SMC alone for adult outpatients with DS.

Discussion

The objectives and design of the trial are summarised, and the aims and procedures of the planned analyses are illustrated. The proposed analysis plan addresses statistical considerations such as maintaining blinding, monitoring adherence with the protocol, describing aspects of treatment and dealing with missing data. The formal analysis approach for the primary and secondary outcomes is described, as are the descriptive statistics that will be reported. This paper provides transparency to the planned inferential analyses for the CODES trial prior to the extraction of outcome data. It also provides an update to the previously published trial protocol and guidance to those conducting similar trials.

Trial registration

ISRCTN registry ISRCTN05681227 (registered on 5 March 2014); ClinicalTrials.gov NCT02325544 (registered on 15 December 2014).

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.

Emotion and dissociative seizures: A phenomenological analysis of patients' perspectives

Quantitative research has indicated that patients with dissociative seizures (DS) show altered responses to emotional stimuli, in addition to considerable emotional distress and dysregulation. The present study sought to further explore emotional processes in this population, to extend previous findings, and to provide a phenomenological insight into patients' perspectives on these issues. Semistructured interviews were carried out with 15 patients with DS, and the principles of interpretative phenomenological analysis (IPA) were adopted in data analysis. Key themes elicited included: i) general emotional functioning; ii) adverse (stressful/traumatic) life experiences; iii) the role of emotions in DS; iv) relating to others; and v) resilience, protective factors, and coping mechanisms. The clinical and theoretical implications of the findings are discussed.

Psychologic treatment of functional neurologic disorders

The management of patients with functional neurologic disorders poses many challenges. Psychologic treatments may well start at the point of delivery of the diagnosis, when careful explanations about the nature of the disorder have to be given to the patient and possibly also relatives/carers. Different conceptual models may assist in explaining the factors underlying the presentation, two of which (functional and dissociative) are briefly outlined here. The challenges for neurologists and psychiatrists of delivering a psychologic formulation as part of the diagnosis delivery are considered, along with the importance of clear communication between professionals involved in the patient's care. Existing literature on treatments incorporating psychologic components suggests that, despite limitations in the study designs and the potential bias in some outcome evaluations, there is evidence to support the use of psychologic interventions for at least some functional neurologic disorders, although larger and better-designed studies are required in this area.

COgnitive behavioural therapy vs standardised medical care for adults with Dissociative non-Epileptic Seizures (CODES): a multicentre randomised controlled trial protocol

BACKGROUND

The evidence base for the effectiveness of psychological interventions for patients with dissociative non-epileptic seizures (DS) is currently extremely limited, although data from two small pilot randomised controlled trials (RCTs), including from our group, suggest that Cognitive Behavioural Therapy (CBT) may be effective in reducing DS occurrence and may improve aspects of psychological status and psychosocial functioning.

METHODS/DESIGN

The study is a multicentre, pragmatic parallel group RCT to evaluate the clinical and cost-effectiveness of specifically-tailored CBT plus standardised medical care (SMC) vs SMC alone in reducing DS frequency and improving psychological and health-related outcomes. In the initial screening phase, patients with DS will receive their diagnosis from a neurologist/epilepsy specialist. If patients are eligible and interested following the provision of study information and a booklet about DS, they will consent to provide demographic information and fortnightly data about their seizures, and agree to see a psychiatrist three months later. We aim to recruit ~500 patients to this screening stage. After a review three months later by a psychiatrist, those patients who have continued to have DS in the previous eight weeks and who meet further eligibility criteria will be told about the trial comparing CBT + SMC vs SMC alone. If they are interested in participating, they will be given a further booklet on DS and study information. A research worker will see them to obtain their informed consent to take part in the RCT. We aim to randomise 298 people (149 to each arm). In addition to a baseline assessment, data will be collected at 6 and 12 months post randomisation. Our primary outcome is monthly seizure frequency in the preceding month. Secondary outcomes include seizure severity, measures of seizure freedom and reduction, psychological distress and psychosocial functioning, quality of life, health service use, cost effectiveness and adverse events. We will include a nested qualitative study to evaluate participants' views of the intervention and factors that acted as facilitators and barriers to participation.

DISCUSSION

This study will be the first adequately powered evaluation of CBT for this patient group and offers the potential to provide an evidence base for treating this patient group.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN05681227 ClinicalTrials.gov NCT02325544.

Epilepsy-related psychosis: a role for autoimmunity?

Postictal psychosis (PIP) is a serious psychiatric complication of epilepsy that occurs in approximately 6% of patients following multiple complex partial or generalized seizures. The psychosis is classically described as having a pleomorphic phenomenology, including paranoid, grandiose, and religious delusions as well as multimodal hallucinations with prominent affective changes and agitation. Little is understood about the pathophysiology of the condition. There has been a recent increase in interest in the relevance of autoimmunity to the pathogenesis of both epilepsy and psychosis. Studies have demonstrated the presence of antibodies directed against synaptic autoantigens (such as the N-methyl-d-aspartate receptor or the voltage-gated potassium channel complex) in approximately 10% of cases of sporadic epilepsy. These same autoantibodies are known to cause encephalopathy syndromes which feature psychiatric symptoms, usually psychosis, as a prominent part of the phenotype as well as other neurological features such as seizures, movement disorders, and autonomic dysfunction. It is beginning to be asked if these antibodies can be associated with a purely psychiatric phenotype. Here, we hypothesize that PIP may be an autoimmune phenomenon mediated by autoantibodies against synaptic antigens. More specifically, we outline a potential mechanism whereby long or repeated seizures cause short-lived blood-brain barrier (BBB) dysfunction during which the brain becomes exposed to pathogenic autoantibodies. In essence, we propose that PIP is a time-limited, seizure-dependent, autoantibody-mediated encephalopathy syndrome. We highlight a number of features of PIP that may be explained by this mechanism, such as the lucid interval between seizures and onset of psychosis and the progression in some cases to a chronic, interictal psychosis.

Cognitive-behavioral therapy for psychogenic nonepileptic seizures: a pilot RCT

OBJECTIVE

To compare cognitive-behavioral therapy (CBT) and standard medical care (SMC) as treatments for psychogenic nonepileptic seizures (PNES).

METHODS

Our randomized controlled trial (RCT) compared CBT with SMC in an outpatient neuropsychiatric setting. Sixty-six PNES patients were randomized to either CBT (plus SMC) or SMC alone, scheduled to occur over 4 months. PNES diagnosis was established by video-EEG telemetry for most patients. Exclusion criteria included comorbid history of epilepsy, <2 PNES/month, and IQ <70. The primary outcome was seizure frequency at end of treatment and at 6-month follow-up. Secondary outcomes included 3 months of seizure freedom at 6-month follow-up, measures of psychosocial functioning, health service use, and employment.

RESULTS

In an intention-to-treat analysis, seizure reduction following CBT was superior at treatment end (group x time interaction p < 0.0001; large to medium effect sizes). At follow-up, the CBT group tended to be more likely to have experienced 3 months of seizure freedom (odds ratio 3.125, p = 0.086). Both groups improved in some health service use measures and on the Work and Social Adjustment Scale. Mood and employment status showed no change.

CONCLUSIONS

Our findings suggest that cognitive-behavioral therapy is more effective than standard medical care alone in reducing seizure frequency in PNES patients.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that CBT in addition to SMC, as compared to SMC alone, significantly reduces seizure frequency in patients with PNES (change in median monthly seizure frequency: baseline to 6 months follow-up, CBT group, 12 to 1.5; SMC alone group, 8 to 5).

Ictal symptoms of anxiety, avoidance behaviour, and dissociation in patients with dissociative seizures

OBJECTIVE

To examine anxiety related seizure symptoms and avoidance behaviour in adults with dissociative (psychogenic non-epileptic) seizures (DS) in comparison with a group suffering from partial epilepsy.

METHODS

25 DS and 19 epilepsy patients completed an attack symptom measure, the hospital anxiety and depression scale, the dissociative experiences scale, and the fear questionnaire.

RESULTS

DS patients reported the presence of significantly greater numbers of somatic symptoms of anxiety during their attacks than the epilepsy group, despite not reporting subjectively higher levels of anxiety. The DS patients also reported higher levels of agoraphobic-type avoidance behaviour than the epilepsy group. Measures of dissociation were higher in the DS group, who also reported greater symptoms of depression.

CONCLUSIONS

The findings support a model whereby DS occur as a paroxysmal, dissociative response to heightened arousal in the absence of raised general anxiety levels. The model has practical implications for clinical assessment and treatment: in clinical practice, inquiry about these symptoms may help in the diagnosis of DS; with respect to treatment, the anxiety related symptoms and avoidance behaviour prevalent in DS are a potential focus for a cognitive behavioural approach analogous to that used in the treatment of other anxiety disorders.

The approach to patients with "non-epileptic seizures"

Up to one fifth of patients who present to specialist clinics with seizures do not have epilepsy. The majority of such patients suffer from psychologically mediated episodes; dissociative seizures, often referred to as "non-epileptic seizures". This paper describes the diagnostic evaluation of seizure disorders, including clinical assessment and the role of special investigations. The organic and psychiatric imitators of epilepsy are outlined and findings on psychiatric assessment are reviewed. This group of patients often proves difficult to engage in appropriate treatment and an approach to explaining the diagnosis is described. As yet there are no controlled trials of treatment in this disorder but preliminary evidence suggests cognitive behavioural therapy is both a rational and promising way forward.

Illness representations, coping styles and mood in adults with epilepsy

It has been generally accepted that psychosocial well-being in people with epilepsy may show an association with the type of coping strategies they adopt. However, relatively little attention has been paid to the way people with epilepsy perceive their illness (illness representations) in determining their well-being and whether these representations are related to coping strategies in determining psychological outcome. We administered the Illness Perception Questionnaire and the Ways of Coping scale and examined their relationship with anxiety and depression scores in 43 adults with chronic epilepsy. Within multiple regression analyses, whilst epilepsy variables were not significantly related to mood, after also adjusting for patients' gender, anxiety scores were best predicted by an increased relative use of escape-avoidance and a decreased relative use of distancing as coping strategies; increased depression scores were best predicted by greater relative use of escape-avoidant and self-controlling coping. Once coping factors had been accounted for, Illness Identity scores independently predicted anxiety scores, indicating that coping was not acting simply to mediate the impact of illness representations on patients' mood. However, illness representations did not independently predict depression, suggesting that in the case of negative affect, coping was acting as a mediating factor. Findings indicate the importance of aspects of epilepsy patients' cognitive representations of their illness, as well as of their coping styles in determining psychological well-being.

Nonepileptic seizures following general anesthetics: a report of five cases

Five patients who developed seizures following a general anesthetic are described. It is not possible to determine retrospectively whether or not the initial attacks were definitely epileptic, but these patients all subsequently received a diagnosis of psychological nonepileptic convulsions/seizures (also known as pseudoseizures, psychogenic nonepileptic seizures, and nonepileptic attack disorder) established by video/EEG telemetry or ictal EEG recordings. In two cases there was evidence of concurrent epilepsy. We suggest that nonepileptic seizures may develop following postanesthetic seizures and that a psychogenic basis for seizures occurring after general anesthetics needs to be considered.

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.

Pseudoseizures and asthma

BACKGROUND

Sexual abuse and head injury are important risk factors of pseudoseizures, reported in about a third of patients. Clinical experience suggests that asthma is another possible risk factor.

OBJECTIVES

To determine the relative prevalence of asthma in patients with pseudoseizures.

METHODS

A retrospective record review was undertaken of reported asthma in 102 patients with pseudoseizures and 70 psychotic controls. The pseudoseizure patients were subgrouped according to method of diagnosis: 47 in whom epilepsy was excluded by capturing a typical attack on video-electroencephalographic monitoring (VEEM), and 55 not diagnostically confirmed with VEEM.

RESULTS

Asthma was reported in 26.5% of pseudoseizure patients, compared with 8.6% of the psychotic controls (chi(2) = 8.6; p = 0.003). Asthma was reported at similar rates in the VEEM confirmed (29.8%) and non-VEEM confirmed (23.6%) pseudoseizure subgroups. The significant excess of reported asthma held for both the VEEM confirmed subjects (Pearson's chi(2) = 5.4, p = 0.02) and non-VEEM confirmed subjects (Pearson's chi(2) = 8.9, p = 0.003).

CONCLUSIONS

There is an association between pseudoseizures and reported asthma. Various models are proposed whereby somatisation, anxiety hyperventilation, and dissociative elaboration may account for the observed association. Both asthma and anxiety hyperventilation may be important risk factors for the development of pseudoseizures. The reported asthma may itself be psychogenic in origin in a proportion of patients. Confirmatory prospective studies are indicated.

Cognitive behaviour therapy with adults with intractable epilepsy and psychiatric co-morbidity: preliminary observations on changes in psychological state and seizure frequency

Cognitive behaviour therapy (CBT) was undertaken with six adults with chronic, poorly controlled seizures and co-existing psychiatric and/or psychosocial difficulties. During 12 sessions of CBT from an experienced CBT Nurse Specialist, treatment focused concurrently on epilepsy-related problems, associated psychopathology and on the development of psychological strategies to reduce seizure occurrence. At the end of treatment participants rated their initial epilepsy-related problem as having less impact on their daily lives and at one-month follow-up reported less deleterious impact on everyday life in terms of their psychological difficulties. In addition participants demonstrated significant improvements in terms of their self-rated work and social adjustment, and in their decreased use of escape-avoidance coping strategies. These positive findings occurred despite the absence of a significant decrease in seizure frequency. Issues raised by the complexity and severity, both of these patients' psychological/psychosocial difficulties and their epilepsy, are discussed in relation to the optimal length of treatment that may be required when adopting a CBT model in this patient group.