Psychogenic non-epileptic seizures
Encyclopedia
Psychogenic non-epileptic seizures (PNES), also known as Non-Epileptic Attack Disorders, are events superficially resembling an epileptic seizure, but without the characteristic electrical discharges associated with epilepsy
. Instead, PNES are psychological in origin, and may be thought of as similar to conversion disorder
. It is estimated that 20% of seizure patients seen at specialist epilepsy clinics have PNES.
, such as syncope
, migraine
, vertigo
, and stroke
, for example. However, it is important to note that between 10-30% of patients with PNES also have epilepsy. Frontal lobe seizures can be mistaken for PNES, though these tend to have shorter duration, stereotyped patterns of movements and occurrence during sleep. Next, factitious disorder
(simulating seizures intentionally for psychological reasons) and malingering
(simulating seizures intentionally for secondary gain such as compensation or avoidance of criminal punishment) are excluded. Finally other psychiatric conditions are eliminated which may superficially resemble seizures, including panic disorder
, schizophrenia
, and depersonalisation disorder.
An experienced clinician is often able to make the diagnosis from a careful history, but the most conclusive test to distinguish true epilepsy from PNES is long term video-EEG monitoring
, with the aim of capturing one or two episodes on both videotape and EEG simultaneously (some clinicians may use suggestion to attempt to trigger an episode). Conventional EEG
may not be particularly helpful because of a high false-positive rate for abnormal findings in the general population, but also of abnormal findings in patients with some of the psychiatric disorders which can mimic PNES.
Many patients with PNES have a history of childhood abuse especially those with motor involvement. Studies also show that the metaphors patients use are key to diagnosis with evidence of repressed memories commonplace. PNES is more likely to occur in young women with the father the most likely perpetrator of abuse.
Following most tonic-clonic
or complex partial epileptic seizures, blood levels of serum prolactin
rise, which can be detected by laboratory testing if a sample is taken in the right time window. However, due to false positives and variability in results this test is relied upon less frequently.
can also connote "false, fraudulent, or pretending to be something that it is not." Non-epileptic seizures are not false, fraudulent, or produced under any sort of pretense.
The condition may also be referred to as non-epileptic attack disorder, functional seizures, or psychogenic non-epileptic seizures. Within DSM IV the attacks are classified as a somatoform disorder
, whilst in ICD 10 the term dissociative convulsions, is used, classed as a conversion disorder
.
If a patient with suspected PNES has an episode during a clinical examination, there are a number of signs which can be elicited to help support or refute the diagnosis of PNES. Compared to patients with epilepsy, patients with PNES will tend to resist having their eyes forced open (if they are closed during the seizure), will stop their hands from hitting their own face if the hand is dropped over the head, and will fixate their eyes in a way suggesting an absence of neurological interference. Mellors et al. warn that such tests are neither conclusive nor impossible for a determined patient with factitious disorder to "pass" through faking convincingly.
. A number of researchers have identified abnormal personality traits or full-blown personality disorder
s in patients with PNES such as borderline personality. The presence of these personality disorders, often related to a trauma in childhood, has led to researchers postulating that PNES may be an expression of repressed psychological harm in response to trauma such as child abuse. Over-emphasising these theories to patients may lead to false memory syndrome so they should be introduced delicately. Other traumatic experiences such as bullying in adulthood, learning disabilities, or adverse family dynamics may also be important pre-disposing or maintaining factors.
An important first step is a discussion with the patient that explains their diagnosis in a sensitive and open manner. A negative diagnosis experience will frustrate the patient and could cause them to reject any further attempts at treatment. Ten points to breaking the diagnosis to the person and their carers are:
Psychotherapy
is the most frequently used treatment, which might include cognitive behavioral therapy, insight-orientated therapy, and/or group work. Where there is a co-morbid psychiatric condition, treatment with antidepressant
medication can be helpful.
Epilepsy
Epilepsy is a common chronic neurological disorder characterized by seizures. These seizures are transient signs and/or symptoms of abnormal, excessive or hypersynchronous neuronal activity in the brain.About 50 million people worldwide have epilepsy, and nearly two out of every three new cases...
. Instead, PNES are psychological in origin, and may be thought of as similar to conversion disorder
Conversion disorder
Conversion disorder is a condition in which patients present with neurological symptoms such as numbness, blindness, paralysis, or fits without a neurological cause. It is thought that these problems arise in response to difficulties in the patient's life, and conversion is considered a psychiatric...
. It is estimated that 20% of seizure patients seen at specialist epilepsy clinics have PNES.
Diagnosis
The differential diagnosis of PNES firstly involves ruling out epilepsy as the cause of the seizure episodes, along with other organic causes of non-epileptic seizuresNon-epileptic seizures
Non-epileptic seizures are paroxysmal events that mimic an epileptic seizure but do not involve abnormal, rhythmic discharges of cortical neurons. They are caused by either physiological or psychological conditions...
, such as syncope
Syncope (medicine)
Syncope , the medical term for fainting, is precisely defined as a transient loss of consciousness and postural tone characterized by rapid onset, short duration, and spontaneous recovery due to global cerebral hypoperfusion that most often results from hypotension.Many forms of syncope are...
, migraine
Migraine
Migraine is a chronic neurological disorder characterized by moderate to severe headaches, and nausea...
, vertigo
Vertigo (medical)
Vertigo is a type of dizziness, where there is a feeling of motion when one is stationary. The symptoms are due to a dysfunction of the vestibular system in the inner ear...
, and stroke
Stroke
A stroke, previously known medically as a cerebrovascular accident , is the rapidly developing loss of brain function due to disturbance in the blood supply to the brain. This can be due to ischemia caused by blockage , or a hemorrhage...
, for example. However, it is important to note that between 10-30% of patients with PNES also have epilepsy. Frontal lobe seizures can be mistaken for PNES, though these tend to have shorter duration, stereotyped patterns of movements and occurrence during sleep. Next, factitious disorder
Factitious disorder
Factitious disorders are conditions in which a person acts as if he or she has an illness by deliberately producing, feigning, or exaggerating symptoms. Factitious disorder by proxy is a condition in which a person deliberately produces, feigns, or exaggerates symptoms in a person who is in their...
(simulating seizures intentionally for psychological reasons) and malingering
Malingering
Malingering is a medical term that refers to fabricating or exaggerating the symptoms of mental or physical disorders for a variety of "secondary gain" motives, which may include financial compensation ; avoiding school, work or military service; obtaining drugs; getting lighter criminal sentences;...
(simulating seizures intentionally for secondary gain such as compensation or avoidance of criminal punishment) are excluded. Finally other psychiatric conditions are eliminated which may superficially resemble seizures, including panic disorder
Panic disorder
Panic disorder is an anxiety disorder characterized by recurring severe panic attacks. It may also include significant behavioral change lasting at least a month and of ongoing worry about the implications or concern about having other attacks. The latter are called anticipatory attacks...
, schizophrenia
Schizophrenia
Schizophrenia is a mental disorder characterized by a disintegration of thought processes and of emotional responsiveness. It most commonly manifests itself as auditory hallucinations, paranoid or bizarre delusions, or disorganized speech and thinking, and it is accompanied by significant social...
, and depersonalisation disorder.
An experienced clinician is often able to make the diagnosis from a careful history, but the most conclusive test to distinguish true epilepsy from PNES is long term video-EEG monitoring
Long-term video-EEG monitoring
Long-term video-EEG monitoring, also known as video telemetry, is a diagnostic technique used in certain patients with epilepsy or seizures. It involves the inpatient hospitalization of the patient for a period of time, typically days to weeks, during which they are continuously monitored and...
, with the aim of capturing one or two episodes on both videotape and EEG simultaneously (some clinicians may use suggestion to attempt to trigger an episode). Conventional EEG
EEG
EEG commonly refers to electroencephalography, a measurement of the electrical activity of the brain.EEG may also refer to:* Emperor Entertainment Group, a Hong Kong-based entertainment company...
may not be particularly helpful because of a high false-positive rate for abnormal findings in the general population, but also of abnormal findings in patients with some of the psychiatric disorders which can mimic PNES.
Many patients with PNES have a history of childhood abuse especially those with motor involvement. Studies also show that the metaphors patients use are key to diagnosis with evidence of repressed memories commonplace. PNES is more likely to occur in young women with the father the most likely perpetrator of abuse.
Following most tonic-clonic
Tonic-clonic seizure
Tonic–clonic seizures are a type of generalized seizure that affects the entire brain...
or complex partial epileptic seizures, blood levels of serum prolactin
Prolactin
Prolactin also known as luteotropic hormone is a protein that in humans is encoded by the PRL gene.Prolactin is a peptide hormone discovered by Henry Friesen...
rise, which can be detected by laboratory testing if a sample is taken in the right time window. However, due to false positives and variability in results this test is relied upon less frequently.
Terminology
The use of older terms including pseudoseizures and hysterical seizures are discouraged. While it is correct that a non-epileptic seizure may resemble an epileptic seizure, pseudoPseudo
The prefix pseudo- is used to mark something as false, fraudulent, or pretending to be something it is not.-See also:*Falsehood*Pseudorealism*Deception*Mimicry*Pseudo.com*Pseudo: Blood of Our Own...
can also connote "false, fraudulent, or pretending to be something that it is not." Non-epileptic seizures are not false, fraudulent, or produced under any sort of pretense.
The condition may also be referred to as non-epileptic attack disorder, functional seizures, or psychogenic non-epileptic seizures. Within DSM IV the attacks are classified as a somatoform disorder
Somatoform disorder
In psychology, a somatoform disorder is a mental disorder characterized by physical symptoms that suggest physical illness or injury - symptoms that cannot be explained fully by a general medical condition, direct effect of a substance, or attributable to another mental disorder . The symptoms that...
, whilst in ICD 10 the term dissociative convulsions, is used, classed as a conversion disorder
Conversion disorder
Conversion disorder is a condition in which patients present with neurological symptoms such as numbness, blindness, paralysis, or fits without a neurological cause. It is thought that these problems arise in response to difficulties in the patient's life, and conversion is considered a psychiatric...
.
Distinguishing features
Some features are more or less likely to suggest PNES but they are not conclusive and should be considered within the broader clinical picture. Features which are common in PNES but rarer in epilepsy include: biting the tip of the tongue, seizures lasting more than 2 minutes, seizures having a gradual onset, a fluctuating course of disease severity, the eyes being closed during a seizure, and side to side head movements. Features which are uncommon in PNES include automatisms (automatic complex movements during the seizure), severe tongue biting, biting the inside of the mouth, and incontinence.If a patient with suspected PNES has an episode during a clinical examination, there are a number of signs which can be elicited to help support or refute the diagnosis of PNES. Compared to patients with epilepsy, patients with PNES will tend to resist having their eyes forced open (if they are closed during the seizure), will stop their hands from hitting their own face if the hand is dropped over the head, and will fixate their eyes in a way suggesting an absence of neurological interference. Mellors et al. warn that such tests are neither conclusive nor impossible for a determined patient with factitious disorder to "pass" through faking convincingly.
Risk factors
Most PNES patients (75%) are women, with onset in the late teens to early twenties being typical. PNES patients often have a history of multiple vague, unexplained medical problems and may have a psychiatric condition such as major depressive disorder or an anxiety disorderAnxiety disorder
Anxiety disorder is a blanket term covering several different forms of abnormal and pathological fear and anxiety. Conditions now considered anxiety disorders only came under the aegis of psychiatry at the end of the 19th century. Gelder, Mayou & Geddes explains that anxiety disorders are...
. A number of researchers have identified abnormal personality traits or full-blown personality disorder
Personality disorder
Personality disorders, formerly referred to as character disorders, are a class of personality types and behaviors. Personality disorders are noted on Axis II of the Diagnostic and Statistical Manual of Mental Disorders or DSM-IV-TR of the American Psychiatric Association.Personality disorders are...
s in patients with PNES such as borderline personality. The presence of these personality disorders, often related to a trauma in childhood, has led to researchers postulating that PNES may be an expression of repressed psychological harm in response to trauma such as child abuse. Over-emphasising these theories to patients may lead to false memory syndrome so they should be introduced delicately. Other traumatic experiences such as bullying in adulthood, learning disabilities, or adverse family dynamics may also be important pre-disposing or maintaining factors.
Treatment
There have been no randomized controlled trials to examine treatment options in PNES. Therefore evidence comes from case reports, small treatment series, and the experience of individual clinicians.An important first step is a discussion with the patient that explains their diagnosis in a sensitive and open manner. A negative diagnosis experience will frustrate the patient and could cause them to reject any further attempts at treatment. Ten points to breaking the diagnosis to the person and their carers are:
- Reasons for concluding they do not have epilepsy
- What they do have (describe dissociationDissociationDissociation is an altered state of consciousness characterized by partial or complete disruption of the normal integration of a person’s normal conscious or psychological functioning. Dissociation is most commonly experienced as a subjective perception of one's consciousness being detached from...
) - Emphasise they are not suspected of "putting on" the attacks
- They are not "mad"
- Triggering "stresses" may not be immediately apparent.
- Relevance of aetiological factors in their case
- Maintaining factors
- May improve after correct diagnosis
- Caution that anticonvulsant drug withdrawal should be gradual
- Describe psychological treatment
Psychotherapy
Psychotherapy
Psychotherapy is a general term referring to any form of therapeutic interaction or treatment contracted between a trained professional and a client or patient; family, couple or group...
is the most frequently used treatment, which might include cognitive behavioral therapy, insight-orientated therapy, and/or group work. Where there is a co-morbid psychiatric condition, treatment with antidepressant
Antidepressant
An antidepressant is a psychiatric medication used to alleviate mood disorders, such as major depression and dysthymia and anxiety disorders such as social anxiety disorder. According to Gelder, Mayou &*Geddes people with a depressive illness will experience a therapeutic effect to their mood;...
medication can be helpful.
Prognosis
Though there is limited evidence, outcomes appear to be relatively poor with a review of outcome studies finding that two thirds of PNES patients continue to experience episodes and more than half are dependent on social security at three year followup. This outcome data was obtained in a referral-based academic epilepsy center and loss to followup was considerable; the authors point out ways in which this may have biased their outcome data.External links
- Article in Neuropsychiatry news – this article has statistical research data which suggests that non-epileptic seizures can be dramatically improved with psychotherapy.
- Epilepsy Foundation article about non-epileptic seizures
- Epilepsy.com article about non-epileptic seizures
- National Society for Epilepsy (UK) article on Non-epileptic attack disorder – a technical article aimed at health professionals