Causes and risk factors
The cause of PNES has not yet been established. One hypothesis is that they are a learned physical reaction or habit the body develops, similar to a reflex. The individual does not have control of the learned reaction, but this can be retrained to allow the patient to control the physical movements again. The production of seizure-like symptoms is not under voluntary control, meaning that the person is not faking; symptoms which are feigned or faked voluntarily would fall under the categories of factitious disorder or malingering.Risk factors for PNES include having a history of head injury, and having a diagnosis of epilepsy. Approximately 10–30% of people diagnosed with PNES also have an epilepsy diagnosis. People diagnosed with PNES commonly report physical, sexual, or emotional trauma, but the reported incidence of these events may not differ between PNES and epilepsy. Diagnosis
According to the Diagnostic and Statistical Manual of Mental Disorders (version 5) the criteria for receiving a diagnosis of PNES are:
One or more symptoms of altered voluntary motor or sensory function. Clinical findings provide evidence of incompatibility between the symptom and recognized neurological or medical conditions. The symptom or deficit is not better explained by another medical or mental disorder. The symptom or deficit causes clinically significant distress or impairment in social, occupational, or other important areas of functioning or warrants medical evaluation.Additionally, the specific symptom type must be reported "with attacks or seizures".Some individuals with PNES have carried an erroneous diagnosis of epilepsy.
This outcome data was obtained in a referral-based academic epilepsy center and loss to follow-up was considerable; the authors point out ways in which this may have biased their outcome data. Outcome was shown to be better in people with higher IQ, social status, greater educational attainments, younger age of onset and diagnosis, attacks with less dramatic features, and fewer additional somatoform complaints.For individuals who pursue treatment for PNES, CBT has shown varying rates of success but it has been established as one of the most promising treatments to date. ReACT has shown reduction in symptoms by 100% seven days after treatment and 82% of individuals who completed the therapy remained symptom free for 60 days. A follow-up has not been done to see if the therapy retained its reduction of symptoms beyond the 60 days. The largest trial of CBT for PNES though found no significant reduction in monthly seizures compared to the control arm at 12 months, however there were significant improvements on a number of secondary outcomes, such as psychosocial functioning, and self-rated and clinician-rated global change. History
Hystero-epilepsy is a historical term that refers to a condition described by 19th-century French neurologist Jean-Martin Charcot where people with neuroses "acquired" symptoms resembling seizures as a result of being treated on the same ward as people who genuinely had epilepsy. The etiology of FND was historically explained in the context of psychoanalytic theory as a physical manifestation of psychological distress and repressed trauma.