Psychogenic non epileptic seizures: a review

Objective

This paper summarizes the recent literature on the phenomena of psychogenic non epileptic seizures (PNES).

Definition and epidemiology

PNES are, as altered movement, sensation or experience, similar to epilepsy, but caused by a psychological process. Although in the ICD-10, PNES belong to the group of dissociative disorders, they are classified as somatoform disorders in the DSM-IV. That represents a challenging diagnosis: the mean latency between manifestations and diagnosis remains as long as 7 years. It has been estimated that between 10 and 30% of patients referred to epilepsy centers have paroxysmal events that despite looking like epileptic episodes are in fact non-epileptic. Many pseudo epileptic seizures have received the wrong diagnosis of epilepsy being treated with anticonvulsants. The prevalence of epilepsy in PNES patients is higher than in the general population and epilepsy may be a risk factor for PNES. It has been considered that 65 to 80% of PNES patients are young females but a new old men subgroup has been recently described.

Positive diagnosis and psychiatric comorbidities

Even if clinical characteristics of seizures were defined as important in the diagnosis algorithm, this point of view could be inadequate because of its lack of sensitivity. Because neuron-specific enolase, prolactin and creatine kinase are not reliable and able to validate the diagnosis, video electroencephalography monitoring (with or without provocative techniques) is currently the gold standard for the differential diagnosis of ES, and PNES patients with pseudoseizures have high rates of psychiatric disorders such as depression, anxiety, somatoform symptoms, dissociative disorders and post-traumatic stress disorder. We found evidence for correlations between childhood trauma, history of childhood abuse, PTSD, and PNES diagnoses. PNES could also be hypothesized of a dissociative phenomena generated by childhood trauma.

Pathophysiology

Some authors report that PNES can be associated with a physical brain disorder playing a role in their development: head injury may contribute to the pathogenesis of PNES. New-onset psychogenic seizures after resective epilepsy surgery or other intracranial neurosurgery have been described. Recent studies found psychogenic seizure disorders associated with brain pathology in the right hemisphere, non specific interictal electroencephalography abnormalities, magnetic resonance imaging changes and neuropsychological deficits. However, complex partial seizures of frontal origin might present similar characteristics with PNES and could be confused with the latter.

Prognosis and treatment

There is actually no clear agreement as the best treatment plan for PNES patients. The PNES diagnosis has to be clearly communicated to the patient. Nevertheless, even after a correct diagnosis is made a high proportion of PNES patients continue to have seizures, serious disability and bad self-reported quality of life. Furthermore, seizure remission cannot be considered a comprehensive measure of medical or psychosocial outcome. Nearly half of the patients who become seizure free remain unproductive and many of these patients continue to have symptoms of psychopathology including other somatoform, depressive, and anxiety disorders. Even if psychiatric comorbidities have to be treated by a psychiatrist? who could also suggest a psychotherapy, in all cases the importance of a neurologist continuing to follow post-diagnosis PNES patients is essential.

Conclusions

PNES is a diagnostic and therapeutic challenge that is costly to patients and to society at large. Further studies are needed to understand this dissociative psychiatric disorder and to propose therapeutic guidelines.     

Patients with epilepsy and psychogenic non-epileptic seizures: an inpatient video-EEG monitoring study

Seizure and EEG characteristics of patients with epilepsy and concomitant psychogenic non-epileptic seizures (PNES) were compared to age and sex matched controls with epilepsy alone in a retrospective case control study. 39 patients with clearly documented epileptic and non-epileptic events were compared to 78 age and sex matched controls, sequentially admitted for video-EEG monitoring with documentation of epilepsy alone. Frontal seizures were higher in prevalence in patients with PNES who had concomitant epilepsy (P<0.001), while temporal seizures were higher in prevalence in patients with epilepsy alone (P<0.04). On regression analysis, the odds of having a frontal seizure was found to be significantly lower in the epilepsy alone group compared to the epilepsy+PNES group (odds ratio 0.13, 95% CI, 0.033-0.51). This significant association between frontal lobe epilepsy and PNES may be related to misattribution of frontal seizures for PNES events, or may reflect frontal lobe cortical dysfunction in this subgroup.     

Patients with epilepsy and patients with psychogenic non-epileptic seizures: Video-EEG, clinical and neuropsychological evaluation

Purpose

The incidence of psychogenic non-epileptic seizures (PNES) is 4.9/100,000/year and it is estimated that about 20–30% of patients referred to tertiary care epilepsy centers for refractory seizures have both epilepsy and PNES.The purpose of our study is to evaluate psychiatric disorders and neuropsychological functions among patients with PNES, patients with epilepsy associated with PNES and patients with epilepsy.

Methods

We evaluated 66 consecutive in-patients with video-EEG recordings: 21 patients with epilepsy, 22 patients with PNES and 10 patients with epilepsy associated with PNES; 13 patients were excluded (8 because of mental retardation and 5 because they did not present seizures or PNES during the recording period).

Results

All patients with PNES had a psychiatric diagnosis (100%) vs. 52% of patients with epilepsy. Cluster B personality disorders were more common in patients with PNES.We observed fewer mood and anxiety disorders in patients with PNES compared with those with epilepsy.We did not find statistically significant differences in neuropsychological profiles among the 3 patient groups.

Conclusion

This study can help to contribute to a better understanding of the impact of PNES manifestations, in addition to the occurrence of seizures, in order to provide patients with more appropriate clinical, psychological and social care.     

Frequency of epilepsy in patients with psychogenic seizures monitored by video-EEG

This study examined the frequency of epilepsy in a consecutive series of patients who received a definitive diagnosis of psychogenic nonepileptic seizures (PNES) after completing inpatient video-EEG (VEEG) monitoring. Of the 1,590 patients receiving definitive diagnosis, 514 (32.3%) were diagnosed with PNES. Twenty-nine (5.3%) of these patients were found to have both PNES and epilepsy. When strict diagnostic criteria are applied, there is little overlap between epileptic seizures and PNES among patients referred for VEEG monitoring.     

Do observer and self‐reports of ictal eye closure predict psychogenic nonepileptic seizures?

PURPOSE: Diagnostic delay in distinguishing psychogenic nonepileptic seizures (PNES) from epileptic seizures may result in unnecessary therapeutic interventions and higher health care costs. Previous studies demonstrated that video-recorded eye closure is associated with PNES. The present study prospectively assessed whether observer or self-report of eye closure could predict PNES, prior to video-EEG monitoring. METHODS: Adults referred to an epilepsy monitoring unit (EMU) were prospectively enrolled into the study. At baseline, self-report of eye closure was assessed by questionnaire, and observer report was obtained by interview. Physicians viewed video clips independent of EEG tracings and determined the duration of eye closure during PNES and epileptic seizures. We evaluated whether video-recorded eye closure identified an episode as PNES using random effects models that accounted for episode clustering by subject. The utility of observer and self-report of eye closure in predicting a diagnosis of PNES was tested using logistic regression. RESULTS: Of 132 enrolled subjects, 112 met study criteria during EMU stay for either PNES (n = 43, 38.4%) or epilepsy (n = 84, 75.0%). Fifteen of the 43 PNES subjects (34.9%) had coexisting epilepsy. Self and observer reports of eye closure were neither sensitive nor specific for the diagnosis of PNES. Self-report of eye closure more accurately predicted actual video-recorded eye closure than observer report. Video-recorded eye closure was 92% specific, but only 64% sensitive for PNES identification. DISCUSSION: Neither observer nor self-report of eye closure, prior to VEEG monitoring, predicts PNES. Video-recorded eye closure may not be as sensitive an indicator of PNES as previously reported.     

Pseudosleep events in patients with psychogenic non-epileptic seizures: prevalence and associations

OBJECTIVES: To determine the prevalence and clinical associations of a history of events during sleep in patients with psychogenic non-epileptic seizures (PNES, pseudoseizures), and to compare the prevalence of a history of sleep events with that in poorly controlled epilepsy. METHODS: Prospective study by semistructured interview of the history of event patterns and their clinical associations in 142 patients with video EEG confirmed PNES, and 100 patients with poorly controlled epilepsy. RESULTS: 84/142 patients with PNES (59%) and 47/100 with epilepsy (47%) gave a history of events during sleep (p = 0.062). In patients with PNES, significant associations were found between a history of sleep events and: convulsive clinical semiology, antiepileptic drug treatment, fatigue, suicide attempts, mood disorder, and physical abuse. A particularly strong association with social security benefit was also found (odds ratio 4.0, p<0.001). CONCLUSIONS: The prevalence of a history of sleep events is similar in PNES and epilepsy, and is of no value in discriminating between the two, although a history of events occurring exclusively during sleep does suggest epileptic seizures. The clinical associations found indicate that a combination of psychopathological and external influences may be important in determining whether or not a patient with PNES gives a history of events during sleep.     

Psychogenic nonepileptic seizures: review and update

The population incidence of psychogenic nonepileptic seizures (PNES) may be only 4% that of epilepsy, but many patients with PNES have a tendency to seek medical attention, and PNES make up a larger share of the workload of neurologists and emergency and general physicians. Although a great number of publications describe how PNES can be distinguished from epileptic seizures, it usually takes several years to arrive at this diagnosis, and three-quarters of patients (with no additional epilepsy) are treated with anticonvulsants initially. However, the management of PNES as epileptic seizures can lead to significant iatrogenic harm. Moreover, the failure to recognize the psychological cause of the disorder detracts from addressing associated psychopathology and enhances secondary somatization processes. This review provides an overview of studies of the diagnosis, etiology, treatment, and prognosis of PNES. Physicians should always consider PNES in the differential diagnosis of a seizure disorder. If a diagnosis of PNES is possible, or a diagnosis of epilepsy in doubt, a clear diagnostic categorization should be sought. This should involve the assessment of the patient by a physician versed in the diagnosis of seizure disorders and, in many cases, the documentation of a typical seizure by video-EEG. Outcome may be improved if the diagnosis is more actively sought, made earlier, and communicated more convincingly.     

Weeping During Psychogenic Nonepileptic Seizures

Ictal weeping may help distinguish psychogenic nonepileptic seizures (PNES) from epileptic seizures. However, the prevalence of weeping during PNES or epileptic seizures is unknown. We reviewed videotapes of recorded events in 84 consecutive patients with PNES or epilepsy. Weeping was observed during 14% of PNES in 31% of patients with PNES. Ictal weeping was not observed in any epileptic seizures occurring in 48 patients. The differences were highly significant. One patient with epileptic seizures originating in the right temporal lobe wept soon after the end of a seizure. Depression was not more common in PNES patients with than without ictal weeping. Weeping during an apparent seizure strongly argues that the event is not epileptic.     

Mortality in a cohort of patients with psychogenic non-epileptic seizures

Some evidence suggests that psychogenic non-epileptic seizures (PNES) are associated with increased mortality. The authors obtained death certificate information in a cohort of 260 patients who presented with PNES between 1999 and 2004. The follow-up period averaged 7.92 years, during which 17 patients died, 12/17 were under the age of 75 years, giving a premature (<75 years) mortality rate of 0.58%, compared with a Scottish mortality rate for the 40-75 years age group of 0.41% per year. The main predictor of death was the patient age at presentation of PNES. There was no correlation with withdrawal of anticonvulsant medication, and death certificate information provided no evidence to suggest that the deaths were related to the seizure disorder. The population had a high mean deprivation rank, providing a possible explanation for a modest increase in premature death rate.     

Driving and Epilepsy: a Review of Important Issues

Driving restrictions in people with epilepsy (PWE) is a highly contentious topic. The fundamental difficulty lies in achieving a balance between safety and practicality. The aim of this review is to provide an overview, history, and rationale behind current laws regarding driving restriction in PWE. We also discuss recent findings that may be helpful to practitioners during individual discussions with PWE including seizure recurrence risk after first seizure, recurrent seizure, and anticonvulsant with drawl and driving restrictions in patients with psychogenic non-epileptic seizures (PNES).     

Efficacy of safety signals in the epilepsy monitoring unit (EMU): should we worry?

There is little consensus regarding the critical safety measures to prevent harm in epilepsy monitoring units (EMUs). We sought to determine whether the safety signals (SS) triggered during EMU events differed by seizure type and the efficacy of SS in alerting responders. We screened 468 consecutive EMU admissions from January 2008 until April 2011 for definitive events to evaluate the first 50 events of complex partial seizures (CPS), generalized tonic-clonic seizures (GTC), and psychogenic non-epileptic seizures (PNES). Response to telemetry signal was slower than to push button (PB). When there was PB alarm, response time was slower in patients with PNES. A higher proportion of PNES were triggered by PB. A greater percentage of epileptic seizures were missed compared with PNES. Future studies investigating more effective techniques to capture every epileptic seizure are warranted as 24/7 monitoring by healthcare professionals is not feasible in many settings.     

Psychiatric disorders in patients with psychogenic non-epileptic seizures, with and without comorbid epilepsy.

PURPOSE: The aim of this study is to describe similarities and differences in epidemiological, psychiatric and semiologic variables between patients with psychogenic none epileptic seizures (PNES) and comorbid epilepsy (mixed PNES), and patients with PNES without comorbid epilepsy (pure PNES). RESULTS: Forty-three patients with PNES diagnosed by Video-EEG were included. Twenty-four had pure PNES, and ninteen mixed PNES. Female population, age, duration of PNES, psychiatric institutionalization, psychopharmacotherapy, dissociative disorders and posttraumatic stress disorder (PTSD), were significantly higher in the pure PNES patients. Suicide attempts, antiepileptic therapy, conversive, affective and personality disorders were frequent in both groups. In the analysis of seizure semiology, the total lack of responsiveness was significantly higher in the mixed PNES group. CONCLUSIONS: Pure PNES patients showed similarities and differences in the psychiatric profile, with a greater prevalence of dissociative disorders and PTSD, factors related to psychiatric severity.     

Comorbid epilepsy and psychogenic non-epileptic seizures: How well do patients and caregivers distinguish between the two

PurposeTo determine whether patients with comorbid epilepsy and psychogenic nonepileptic seizure (PNES) and their caregivers can distinguish between these two events at least one year after initial diagnosis, and to investigate factors associated with correct identification.MethodsAdult patients with at least a one year diagnosis of both epilepsy and PNES, confirmed through video-electroencephalography (VEEG), were selected. Patients and a caregiver of their choice were interviewed and shown videos containing the patients’ epileptic and PNES events. Variables associated with correct identification of events by patients and their caregivers were evaluated.ResultsTwenty-four patients participated in the study. Mean time between VEEG diagnosis and enrollment in the study was 26.8 months (±12.4). Six of patients correctly distinguished between the events shown. Factors associated with correct identification were the absence of intellectual disability, unremitted PNES, and a degree of preserved awareness during the PNES event. Twelve caregivers correctly distinguished between the events shown. Factors associated with correct identification among caregivers were the presentation of only one epileptic seizure type in the patient, and the participation of the caregiver during VEEG monitoring and communication of PNES diagnosis to the patient.ConclusionA significant proportion of patients with epilepsy and PNES and their caregivers seem to be unable to discriminate between these events a year after diagnosis. These findings have implications for both clinical follow-up and research involving this population. Future research should further investigate methods that would allow patients and their caregivers to better distinguish between these two events.     

Etiologic and diagnostic factors of psychogenic pseudo-epileptic seizures

The term psychogenic pseudoepileptic seizures (or psychogenic non-epileptic seizures-NES) generally refers to episodes of psychological origin that resemble epilepsy but without underlying epilepsy. The diagnosis of pseudo-epileptic seizures is confirmed in 5-33% of patients that are considered to suffer from refractory epilepsies. Making a correct diagnosis in patients presenting with attack disorders is sometimes very difficult. However, the best way to establish differential diagnosis of epileptic and pseudoepileptic seizures is to apply long-term video EEG monitoring. Triggering a seizure by means of placebo administration or suggestion to start or stop seizure can be also a helpful method in differential diagnosis. Over the last decade epileptologist have been paying increasing attention to the Minnesota Multiphasic Personality Inventory (MMPI) scales in describing or distinguishing real epileptic seizures vs. non-epileptic attacks. The results of the study may have practical implications for neurological and epilepsy centres, and for improving clinical knowledge and allow to establish aetiological classification of psychogenic pseudoepileptic seizures.     

Psychogenic non-epileptic seizures—Diagnostic issues: A critical review

In this review we systematically assess our current knowledge about psychogenic non-epileptic seizures (PNES), epidemiology, etiology, with an emphasis on the diagnostic issues. Relevant studies were identified by searching the electronic databases. Case reports were not considered. Articles were included when published after 1980 up till 2005 (26 years). A total of 84 papers were identified; 60 of which were actual studies. Most studies have serious methodological limitations. An open non-randomized design, comparing patients with PNES to patients with epilepsy is the dominant design. The incidence of PNES in the general population is low. However, a relatively high prevalence is seen in patients referred to epilepsy centres (15–30%). Caution is needed in the clinical interpretation of ictal features suggested to be pathognomic for PNES. Video–EEG is widely considered to be the gold standard for diagnosing PNES. Still the differential diagnosis epileptic/non-epileptic seizures can be difficult. Despite the current available technical facilities, the mean latency between onset of PNES and final diagnosis as being non-epileptic and psychogenic is approximately 7 years. One of the reasons for diagnostic delay is that the diagnosis of PNES is often limited to a ‘negative’ process and consequently PNES is characterized as a ‘non-disease’ (i.e. ‘not epilepsy’). The psychological diagnosis is thus an important, although not a conclusive, ‘second phase’ aspect of medical decision making. Specific relations between seizure presentation and underlying psychological mechanisms are not conclusive. A classification between major motor manifestations and unresponsiveness is recognized. With respect to psychological etiology, a heterogeneous set of factors have been identified that may be involved in the causation, development and provocation of PNES.     

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.     

Diagnosing psychogenic nonepileptic seizures: Video-EEG monitoring,suggestive seizure induction and diagnostic certainty

Psychogenic nonepileptic seizures (PNES) can remain undiagnosed for many years, leading to unnecessary medication and delayed treatment. A recent report by the International League Against Epilepsy Nonepileptic Seizures Task Force recommends a staged approach to the diagnosis of PNES (LaFrance, et al., 2013). We aimed to investigate its practical utility, and to apply the proposed classification to evaluate the role of long-term video-EEG monitoring (VEEG) and suggestive seizure induction (SSI) in PNES workup.Using electronic medical records, 122 inpatients (mean age 36.0 ± 12.9 years; 68% women) who received the diagnosis of PNES at our epilepsy center during a 4.3-year time period were included. There was an 82.8% agreement between diagnostic certainty documented at discharge and that assigned retroactively using the Task Force recommendations. In a minority of cases, having used the Task Force criteria could have encouraged the clinicians to give more certain diagnoses, exemplifying the Task Force report's utility.Both VEEG and SSI were effective at supporting high level diagnostic certainty. Interestingly, about one in four patients (26.2%) had a non-diagnostic (“negative”) VEEG but a positive SSI. On average, this subgroup did not have significantly shorter mean VEEG recording times than VEEG-positive patients. However, VEEG-negative/SSI-positive patients had a significantly lower habitual seizure frequency than their counterparts. This finding emphasizes the utility of SSI in ascertaining the diagnosis of PNES in patients who do not have a spontaneous habitual event during VEEG due to, for example, low seizure frequency.     

The spectrum of psychogenic non-epileptic seizures and comorbidities seen in an epilepsy monitoring unit

We sought to study characteristics of patients presenting with psychogenic non-epileptic seizures (PNES), with and without major psychiatric comorbidity. A total of 39 patients who were diagnosed with PNES in a tertiary care setting were studied, and those patients with and without axis I psychiatric disorders in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) were compared. The mean time in confirming the diagnosis was 9 years. More than half the patients were taking anti-epileptic medications when they presented for video-electroencephalographic monitoring. The mean monitoring time required to capture a PNES was 0.6 days. Comorbid chronic medical conditions were found in 38.5% and axis I-psychiatric diagnoses in 48.7%. There were no significant differences in characteristics between those with and without major psychiatric comorbidities.     

Changing the diagnosis from epilepsy to PNES: Patients’ experiences and understanding of their new diagnosis

ObjectiveTo describe patients’ experiences when diagnosed with psychogenic non-epileptic seizures (PNES).MethodsThe study was based on in-depth interviews with ten patients, previously diagnosed with epilepsy and treated with antiepileptic drugs (AEDs) whose seizures were subsequently defined as PNES. The empirical material was analyzed by systematic text condensing strategies within the interpretative tradition.ResultsSwitch in diagnosis was demanding, both cognitively and emotionally. The patients had difficulty understanding the diagnosis. When the cause of the seizures was unclear, this resulted in feelings of hopelessness and helplessness, a need for re-evaluation of self-understanding, and increased levels of patient stress. The patients felt that with the change in diagnosis, responsibility was transferred from the health authorities to themselves.ConclusionsThe mode of communicating the PNES diagnosis may be decisive for the patients’ treatment motivation and ability to cope with the disorder. In order to avoid the patients feeling that they have been abandoned with a difficult diagnosis, close cooperation between neurologists and psychiatrists is essential.