Original articleFactors involved in the long-term prognosis of psychogenic nonepileptic seizures
Introduction
Psychogenic nonepileptic seizures (PNES) are a relatively frequently reported symptom. For example, 7-10% of patients referred to a specialized epilepsy center in The Netherlands have PNES [1] and, internationally, estimates of up to 33% have been mentioned [2]. In theory, the distinction between epileptic seizures and PNES is evident [3]. Epileptic seizures are the clinical manifestation of a sudden abnormal change in brain function, accompanied by excessive electrical discharge of brain cells. PNES are defined as a sudden disruptive change in a person's behavior, which is usually time-limited and resembles or is mistaken for epilepsy but is not accompanied by abnormal paroxysmal discharges on electroencephalogram (EEG) and occurs as a symptom of emotional disturbances, personality factors, or present or historical social circumstances [4], [5], [6]. Although diagnosis can be difficult, diagnostic features have been better characterized in recent years. Diagnosing PNES is important because of potential iatrogenic hazards. Patients may be diagnosed as suffering from intractable epilepsies and may be overtreated [7]. There are indications that prognosis in the long term may be worse in such cases [8]. In addition, long periods of uncertainty of the diagnosis may have a negative impact on social development and occupational opportunities [9], which again may have long-lasting effects. Comparatively little research has been done on long-term prognosis after the diagnosis [10], [11], [12]. Validated treatments and controlled trials are lacking [13]. Furthermore, follow-up period is mostly relatively short, varying from 3 months to a year after diagnosis [14], [15].
The definition of PNES is hindered by a diversity of conflicting terminologies, such as hysterical seizures, psychogenic seizures, nonepileptic seizures, and functional seizures [16], [17]. In the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, PNES is classified as a “conversion disorder with seizures or convulsions.” This variation in terminology represents a variety of models proposed to explain PNES. In fact, theories regarding the causes of these seizures are probably as diverse as the phenomenology of this type of seizure. Using Diagnostic and Statistical Manual of Mental Disorders, Third Edition criteria, Stewart et al. [18] were able to uncover several forms of psychopathology in patients with PNES, with a clear tendency for the combination of borderline and antisocial personality disorders. A remarkable finding was that hysteria was not a common diagnosis. The synonym “hysterical seizure” for PNES is, therefore, not correct. The variety of theoretical models explaining PNES probably reflects the heterogeneity of the psychogenic etiology of PNES, which can be a symptom of various affective and psychiatric factors [19], [20]. As yet, there is no accepted model explaining the psychogenic factors leading to PNES. There are indications that, often, more than one factor or psychogenic mechanism operate in PNES [15], [21].
Some attempts have been made to classify patients with PNES into distinct groups requiring different types of interventions and with different prognoses [22]. For example, persisting seizures are expected to occur in patients with personality disorders [8], [23], whereas patients who have PNES because of recently experienced extreme stressors are considered relatively easy to treat and may, therefore, have PNES only as a temporary symptom [24]. The outcome may, therefore, help us to identify some psychogenic mechanisms. We lack, however, knowledge about the prognosis of PNES, as most studies are cohort studies that only report on the diagnosis but do not provide follow-up data. Long-term outcome may also help us to distinguish between “subtypes” of PNES, as patients with persistent seizures over time may have different psychogenic mechanisms in comparison to patients with full seizure remission.
With regard to outcome, there are different studies suggesting that seizure control alone is not a comprehensive measure of good medical or psychosocial outcome in PNES [11], [25]. Several studies have shown that other outcomes, such as employment status [26], may be of greater importance for patients. A consensus report on PNES treatment emphasized that if an intervention improved seizure control without changing the hypothesized etiology, the validity of the treatment could be called into question [13].
In this study, we will therefore reassess patients diagnosed with PNES 4-6 years after the initial diagnosis in a tertiary referral epilepsy center. Reassessments will be aimed at seizure frequency and possible psychogenic outcomes.
Section snippets
Design
Patients were consecutively included when:
- 1.
They had a diagnosis of PNES. Patients with epilepsy and PNES as comorbid symptoms were not included.
- 2.
The diagnosis had been confirmed in a tertiary referral epilepsy center using clinical description and additional EEG investigations (such as EEG videotelemetry). The type of EEG investigation was based on clinical indications such as patient history and seizure semiology.
- 3.
Diagnosis was made in the period 1998-2000.
- 4.
Normal intelligence was assessed
Results
Table 1 shows the most important clinical and demographic characteristics of the study sample. The average age of the patient sample was 30.4 years (S.D.=10.7; range, 15-49 years). Age had a normal distribution. The vast majority of patients in the sample were female (86.4%). Personal situation varied considerably: 31.8% of patients were living with parents, whereas almost 40.9% of patients were married or were living together. A smaller part of the sample was divorced and single. Lower
Discussion
Whereas none of the patients was seizure-free at diagnosis, a substantial portion of this group was in complete remission at end point. Although group size was limited, the results were convincing: at the time of diagnosis, none of the patients was seizure-free or had only yearly seizures, whereas at end point, 7 of 22 patients were completely in remission and 3 patients had only occasional seizures. The number of patients with daily seizures dropped from nine to two. It has not been fully
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2020, Epilepsy and BehaviorAvoidance in nonepileptic attack disorder: A systematic review and meta-analyses
2019, Epilepsy and BehaviorCitation Excerpt :The remaining 22 articles were read in full to determine eligibility. Eight articles were excluded: five did not consider constructs, which could be considered avoidance [3,33–35]; two used a mixed group with NEAD and functional neurological disorder [36,37], and one was excluded as only a summary was translated into English [38]. Thus, 14 papers were included in the narrative review; six of these articles were included in the meta-analysis comparing NEAD to an HC group; and four were included in the meta-analysis comparing NEAD to an EC group (Fig. 1).
Emotion dysregulation in patients with psychogenic nonepileptic seizures: A systematic review based on the extended process model
2018, Epilepsy and BehaviorCitation Excerpt :In another study, DES scores did not discriminate between pwPNES and epilepsy in a logistic regression model, whereas levels of somatization and psychopathology did and a positive correlation between DES scores and a NEAD severity index lost significance when somatization and psychopathology were controlled for [67]. Finally, when pwPNES were followed up for 4–6 years postdiagnosis, those with reduced seizure frequency also experienced fewer dissociative symptoms [83]. Taken together, these findings suggest self-report measures of dissociation are closely related to current distress or psychopathology.