Idiopathic Seizures
Written by Ellese Elliott
[Psychogenic / Non-Epileptic Seizures]
An epileptic seizure is underpinned by a mechanism involving a large group of neurons that are hyper-excitable and hyper-synchronised[1]. This mechanism is identified using an electroencephalogram (EEG). However, not all seizures are epileptic; meaning, they are not underpinned by this specific neurological mechanism, and are therefore called non-epileptic seizures (NES).
Non-epileptic seizures have traditionally been bisected into the sub categories: physiological and psychogenic. Physiological NES’s are thought to have physiological causes and include a broad spectrum of disorders; such as syncope, sleep disorders, paroxysmal movement disorders, paroxysmal endocrine disturbances, transient ischaemic attacks (TIAs) and more. Conversely, psychogenic NES’s are thought to be caused by the mind[2] and have been known by the terms: psychogenic-seizures[3], hysterical seizures[4], imitation seizures[5], dissociative seizures[6], functional seizures/attacks[7], and by the least preferential name, pseudo-seizures[8]; a term that has now been widely rejected by the scientific community. This is not an exhaustive list.
However, in light of emerging evidence of differential neurological correlates present alongside ‘psychogenic seizures’, and the spurious reasoning that the physiological/psychogenic distinction is based on, we believe that this distinction will soon be rendered obsolete and the concept of psychological seizures abandoned. As such, we prefer to use the term ‘idiopathic seizures’; meaning, seizures of unknown origin. This article will refer to what is known as ‘psychogenic seizures’ as idiopathic seizures for these reasons. Seizures then have different mechanisms and causes. But what are seizures?
Reuber and Kurtheen offer a definition of non-epileptic attack disorder (NEAD) that we think can be used generally to describe seizures; being,
“Episodes of paroxysmal impairment of self-control associated with a range of motor, sensory and mental manifestations…[9]“.
However, not all seizures sufferers have reported that their seizures are paroxysmal (sudden), and report more of a gradual onset. An omission of the term paroxysmal may be appropriate.
Manifestations of idiopathic seizures can include: convulsions, stiffening, tremors, staring spells, unresponsiveness, biting the tip of the tongue, side to side head movements,
crying and/or screaming, neck and spine bending backwards, eyes closed/flickering, and thrusting of the hips. To note, this is not a comprehensive list and seizures may fluctuate in severity[10].
These features are strikingly similar to epilepsy, and at first glance, it may be difficult to differentiate epilepsy from idiopathic seizures. However, Dr Jon Stone presents a list of typical features of idiopathic seizures that the doctor can use to differentiate these from epileptic seizures, which include; the longevity of the seizure, the type of movements of your head and limbs if appropriate, the duration of unresponsiveness, and the duration of the onset, or ‘warning period'[11]. Failing this, Selim R. Benbadis, M.D., Director of Comprehensive Epilepsy Program, states that physicians have the ability to diagnose idiopathic seizures by using EEG-video monitoring[12]. However, diagnosis is another problematic area due to the unknown cause(s) of idiopathic seizures and the fact that some epileptic seizures do not appear on the EEG recording.
Treatment
In a treatment review of idiopathic seizures conducted by Gaston Baslet in 2012, Baslet found that psychotherapy and psychopharmacotherapy are very promising approaches, but further study is required. Cognitive behavioural therapy (CBT) in idiopathic seizures is the only psychotherapeutic study reported by the treatment review to have been studied in a pilot randomised control trial. Therefore, CBT has the best supported evidence than any other psychotherapeutic study[13]. In the most promising cited study, Goldstein et al. found that the frequency of idiopathic seizures were significantly lower at the end of a 12 week session treatment with standard medical care(SMC), then the control group who only received (SMC). However, after 12 months, the difference of seizure frequency between these two groups was not statistically significant[14]. Mindfulness-based interventions, EMDR, and sensorimotor therapy are other possible therapies that may be used to treat idiopathic seizures however; they have not been systematically studied in regard to idiopathic seizures.
LaFrance et al. conducted a randomized, double blind, placebo-controlled trial over a 12 week period which evaluated the effectiveness of flexibledose sertraline at reducing the frequency of idiopathic seizures. There was a 45% decrease in biweekly event frequency, where the control group showed an 8% increase. However, due to the small number of participants, more studies need to be conducted in order to warrant this type of psychopharmotherapeutic treatment.
CBT with SMC and Setraline are reported by Baslet to be the most promising treatments, but require further investigation in larger samples. Since, in 2014, LaFrance et al. conducted a pilot randomized clinical trial involving 38 patients and found in the arm which combined psychotherapy (cognitive behavioural therapy informed psychotherapy (CBT-ip)) with sertraline, seizures reduced by 59.3%. In distinction, the CBT-ip arm showed a 51.4% seizure reduction, whereas the sertraline-only arm did not show a reduction in seizures[15]. Due to the conflicting results of the outcome of Setraline on seizure reduction, and the again small amount of participants, as Baslet said previously, more tests need to be done. However, the fact that other psychotherapeutic and psychopharmotherapeutic interventions haven’t been studied leaves the gate open to new research to be done in these areas.
It is very difficult to suffer with seizures, but we also recognise how difficult and frustrating it is to not know the actual cause of your seizures. Irrespective of cause, all patients deserve respectable care and effective treatment plans and we hope more studies will be conducted in the future into the cause and treatment of idiopathic seizures. We also implore the scientific community to refer to this phenomenon as idiopathic seizures until such a time when they have established such evidence.