Psychogenic seizures/ Non-epileptic events
Nitin K. Sethi, MD
Assistant Professor of Neurology
New York-Presbyterian Hospital
Weill Cornell Medical Center
New York, NY 10065
Non-epileptic events are paroxysmal episodes that resemble and are often misdiagnosed as epileptic seizures. Non-epileptic events can be further of two kinds
Psychogenic non-epileptic seizures (PNES)
Non epileptic but not psychogenic (“physiologic”) event
Non-epileptic but not psychogenic (physiologic) events: examples include
- Myoclonus which is not cortical (segmental/ spinal)
- Parasomnias: sleep walking, nocturnal panic attacks, nightmares, sleep terrors
- Complicated migraine
- Transient ischemic attacks
- Startle induced phenomena
Psychogenic non-epileptic events
Multiple terminology: pseudoseizures, nonepileptic seizures, nonepileptic events, and psychogenic non-epileptic seizures.
By definition PNES are psychogenic (psychological) in origin.
- a form of conversion disorder or more broadly somatoform disorder—these are involuntary
- a form of malingering or factitious disorder—these are voluntary
Frequency/ sex ratio and age of onset
- Up to one in five patients with apparently medical intractable epilepsy referred to epilepsy centres.
- Incidence and prevalence varies in different countries: likely on account of differences in social and cultural norms.
- More frequent in women as compared to men.
- Typical age of onset is young adulthood
Making the diagnosis
Misdiagnosis is common!!!
Patients present with history of uncontrolled seizures/ typical events inspite of
multiple inpatient admissions
multiple anti-epileptic drugs (AEDs)
Making the diagnosis
- Good history forms the backbone
- History of typical event
- From patient
- From family/ caregiver/bystander
Points to consider:
Does the event occur out of sleep or do the events always occur during daytime when people are around
Specific triggers that are unusual for epilepsy: events are clearly precipitated by emotional stress (“I become angry and then shake”)
Circumstances in which attacks occur: around an audience (family, social events)
Details of the typical event: motor movements characteristics that are inconsistent with epileptic seizures: side-to-side shaking of the head, bilateral asynchronous trashing movements which are out of phase, weeping, verbalization and arching of the back (pelvic thrusting), eyes are closed and cannot be pried open.
History of other coexisting psychogenic conditions: fibromyalgia, chronic fatigue syndrome, IBS.
Good psychosocial history: depression, bipolar disorder, personality disorders (hysterical personality), family dynamics.
History of sexual abuse is specially important.
Making the diagnosis
VIDEO-EEG study is the gold standard
- Helps to make an electroclinical correlation: capture a typical event on the video and interpret the electrographic correlate.
- No change in the background EEG during the clinical event.
- Clinical event is inconsistent with known seizure semiology: event starts-stops-then starts again, awareness is preserved in spite of bilateral motor convulsive activity.
If Video-EEG facility is unavailable: routine EEG, ambulatory EEG, extended EEG—with suggestibility—lower yield
Imaging studies may or may not be normal: correlate the MRI/ CT with the history
Blood tests: prolactin (increased for about 30 minutes after a generalized convulsion)—impractical, hence not too useful.
patients frequently do not accept their diagnosis (” I am not crazy” ” I shall see another doctor”)
hence the way one delivers/explains the diagnosis to patients and their families is an art: some physicians are blunt, others are more vague or mask their words
Patients may or may not be agreeable to seeing a psychiatrist
- Assure continuity of care
- Be supportive
- Be non confrontational
can AEDs be tapered off?
Does the patient have co-existing true seizures?
So your doctor may get other professionals involved: social workers, psychiatrists
- Not all patients become “seizure”/spell free—many in fact do not
- Males become spell free more than females
- If they have a previous psychiatric diagnosis or some motive like disability/ unresolved marital stress—they shall not become spell free
- Events may become less dramatic—less hospitalizations or visits to the doctor
- They may be lost to follow up and find another doctor