Auras in psychogenic nonepileptic seizures

Prevalence of ictal injuries in functional (psychogenic nonepileptic) seizures: A systematic review and meta-analysis

OBJECTIVE

Ictal injuries have long been considered typical signs of epileptic seizures. However, studies have shown that patients with functional seizures (FS)-also named psychogenic nonepileptic seizures-can also present these signs, misleading physicians and delaying a correct diagnosis. This systematic review aimed to assess the prevalence of injuries from FS.

METHODS

A literature search was performed in PubMed, Embase, LILACS (Latin American and Caribbean Health Sciences Literature), Scopus, Web of Science, PsycINFO, Google Scholar, OpenGrey, and ProQuest. Observational studies were included. The risk of bias was assessed using the Joanna Briggs Institute (JBI) checklist for studies reporting prevalence data. RStudio was used for meta-analyses. Cumulative evidence was evaluated according to Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) criteria.

RESULTS

From the 2607 identified records, 41 studies were included in the qualitative synthesis, and 28 were included in meta-analyses. A meta-analysis of 13 studies, including 1673 individuals, resulted in an overall lifetime prevalence of injuries due to FS per person of 25% (95% confidence interval [CI] = 19%-32%, I2  = 88%). Considering a limited period (video-electroencephalographic [VEEG] monitoring days), a meta-analysis of 13 studies, including 848 individuals, resulted in an injury prevalence due to FS per person of .7% (95% CI = 0%-3%, I2  = 73%). Also, a meta-analysis of eight studies, including 1000 individuals, resulted in a prevalence of injuries per FS of .1% (95% CI = 0%-.98%, I2  = 49%). The certainty in cumulative evidence assessed by GRADE was rated "very low" for lifetime prevalence of injuries per person, "low" for prevalence per person during VEEG monitoring, and "moderate" for prevalence per number of FS.

SIGNIFICANCE

Overall pooled lifetime prevalence of injuries due to FS per person was 25%. In comparison, the prevalence of injuries per person during VEEG monitoring and per functional seizure was .7% and .1%, respectively. [Correction added on 07 October 2023, after first online publication: In the preceding sentence, 'consecutively' was corrected to 'respectively'.] The evidence of the occurrence of injuries due to FS breaks the paradigm that epileptic seizures can cause injuries but FS cannot.

Somatosensory Auras in Epilepsy: A Narrative Review of the Literature

An aura is a subjective experience felt in the initial phase of a seizure. Studying auras is relevant as they can be warning signs for people with epilepsy. The incidence of aura tends to be underestimated due to misdiagnosis or underrecognition by patients unless it progresses to motor features. Also, auras are associated with seizure remission after epilepsy surgery and are an important prognostic factor, guiding the resection site and improving surgical outcomes. Somatosensory auras (SSAs) are characterized by abnormal sensations on one or more body parts that may spread to other parts following a somatotopic pattern. The occurrence of SSAs among individuals with epilepsy can range from 1.42% to 80%. The upper extremities are more commonly affected in SSAs, followed by the lower extremities and the face. The most common type of somatosensory aura is paresthetic, followed by painful and thermal auras. In the primary somatosensory auras, sensations occur more commonly contralaterally, while the secondary somatosensory auras can be ipsilateral or bilateral. Despite the high localizing features of somatosensory areas, cortical stimulation studies have shown overlapping sensations originating in the insula and the supplementary sensorimotor area.

Aura: epilepsy vs. functional (psychogenic) seizures

PURPOSE

To compare auras between three groups of people with seizures [i.e., Idiopathic generalized epilepsies (IGE) vs. Temporal lobe epilepsy (TLE) vs. Functional seizures (FS)].

METHODS

All patients, 10 years of age or older, with a diagnosis of IGE, TLE, or FS were prospectively registered in an electronic database and retrospectively studied at the outpatient epilepsy clinic at Shiraz University of Medical Sciences, Shiraz, Iran, from 2008 until 2020.

RESULTS

One thousand and three hundred ninety-one patients were studied (480 with IGE, 617 with TLE, and 294 with FS). Among patients with TLE, 63.5% of individuals reported auras; this figure was 68% in the FS and 12.7% in the IGE groups (p < 0.00001). Odds ratio of having auras in the TLE group compared with the IGE group was 11.96 (95% CI: 8.73-16.39; p = 0.0001). Odds ratio of having auras in the TLE group compared with the FS group was 0.81 (95% CI: 0.61-1.10; p = 0.1840). Odds ratio of having auras in the FS group compared with the IGE group was 14.61 (95% CI: 10.15-21.02; p = 0.0001). The following auras were more frequent among patients with TLE: emotional, cognitive, epigastric, and olfactory/gustatory. The following auras were more frequent among patients with FS: headache and dizziness/vertigo.

CONCLUSION

Auras are not specific to focal epilepsies. Future studies should investigate auras in large cohorts of patients with focal or generalized epilepsies and also those with FS to determine the exact clinical value of each aura.

Reliability of additional reported seizure manifestations to identify dissociative seizures

PURPOSE

Descriptions of seizure manifestations (SM), or semiology, can help localize the symptomatogenic zone and subsequently included brain regions involved in epileptic seizures, as well as identify patients with dissociative seizures (DS). Patients and witnesses are not trained observers, so these descriptions may vary from expert review of seizure video recordings of seizures. To better understand how reported factors can help identify patients with DS or epileptic seizures (ES), we evaluated the associations between more than 30 SMs and diagnosis using standardized interviews.

METHODS

Based on patient- and observer-reported data from 490 patients with diagnoses documented by video-electoencephalography, we compared the rate of each SM in five mutually exclusive groups: epileptic seizures (ES), DS, physiologic seizure-like events (PSLE), mixed DS and ES, and inconclusive testing.

RESULTS

In addition to SMs that we described in a prior manuscript, the following were associated with DS: light triggers, emotional stress trigger, pre-ictal and post-ictal headache, post-ictal muscle soreness, and ictal sensory symptoms. The following were associated with ES: triggered by missing medication, aura of déjà vu, and leftward eye deviation. There were numerous manifestations separately associated with mixed ES and DS.

CONCLUSIONS

Reported SM can help identify patients with DS, but no manifestation is pathognomonic for either ES or DS. Patients with mixed ES and DS reported factors divergent from both ES-alone and DS-alone.

Marital status in patients with functional (psychogenic nonepileptic) seizures: An international study

PURPOSE

The study aimed to investigate the marital status in a cohort of patients with functional seizures from seven countries in four continents. Factors associated with marital status were also explored.

METHODS

Adult patients with functional seizures who were admitted to the epilepsy monitoring units at centers in Iran, Qatar, USA, France, Georgia, Egypt, and United Arab Emirates (UAE) were retrospectively identified. Marital status was assessed in the whole cohort.

RESULTS

Four hundred thirty-two patients were included (241 from Iran, 52 from France, 48 from Qatar, 41 from the USA, 19 from UAE, 18 from Egypt, and 13 from Georgia); 302 were women and 130 were men. One hundred fifty (35%) subjects were single, 245 (57%) were married, and 37 (8%) were separated (31 divorced, 7%; 6 widowed, 1%). Auras with functional seizures were less frequently reported by single people in comparison with that by married patients (54% vs. 61%) [odds ratio (OR) = 0.58]. Separated people compared with those who were married less often had auras with their functional seizures (27% vs. 61%; OR = 0.26) and more often reported a history of sexual abuse (49% vs. 12%; OR = 6.14).

CONCLUSION

The marital status has significant associations with the semiology of functional seizures. A history of sexual abuse is significantly associated with being separated and should be inquired and tackled appropriately during the management process of patients with functional seizures.

Suggestive seizure induction for inpatients with suspected psychogenic nonepileptic seizures

OBJECTIVE

To determine the utility of suggestive seizure induction for inpatient work-up of suspected psychogenic nonepileptic seizures (PNES).

METHODS

Prospective study of epilepsy center inpatient admissions with suspected PNES. Patients were randomized to undergo suggestive induction first (group A) and then, if necessary, long-term video-electroencephalography (EEG) monitoring, or vice versa (group B). Diagnostic pathways were compared. Potential clinical predictors for diagnostic success were evaluated.

RESULTS

Length of in-hospital stay did not significantly differ between groups. Suspicion of PNES was confirmed in 43 of 77 (56%) patients, evenly distributed between group A (22 of 39) and group B (21 of 38). In nine patients, recorded habitual seizures were epileptic and in 25 cases, no diagnostic event could be recorded. Diagnosis of PNES was ascertained primarily by recording a typical seizure through suggestive induction in 24 patients and through long-term monitoring in 19 patients. In group A (induction first), monitoring was not deemed necessary in 21% of cases. In group B (monitoring first), 13% would have remained inconclusive without suggestive induction. Patients who reported triggers to their habitual seizures were not more likely to have spontaneous or provoked PNES during monitoring or suggestive inducion, respectively. Patients with subjective seizure prodromes (auras) were significantly more likely to have a PNES during suggestive induction than those without (odds ratio [OR] 3.4, 95% confidence interval [CI] 1.1-10.4). There was no significant difference in seizure frequency between patients with spontaneous PNES during long-term monitoring and those with nondiagnostic monitoring sessions.

SIGNIFICANCE

Our results support the notion that suggestive seizure induction can reduce the number of inconclusive inpatient workups, and can obviate resource-intensive long-term monitoring in one fifth of cases. Patients who are aware of prodromes might have a higher chance of having seizures induced through suggestion.

Psychogenic Non-epileptic Seizures and Pseudo-Refractory Epilepsy, a Management Challenge

Psychogenic nonepileptic seizures (PNES) are neurobehavioral conditions positioned in a gray zone, not infrequently a no-man land, that lies in the intersection between Neurology and Psychiatry. According to the DSM 5, PNES are a subgroup of conversion disorders (CD), while the ICD 10 classifies PNES as dissociative disorders. The incidence of PNES is estimated to be in the range of 1.4-4.9/100,000/year, and the prevalence range is between 2 and 33 per 100,000. The International League Against Epilepsy (ILAE) has identified PNES as one of the 10 most critical neuropsychiatric conditions associated with epilepsy. Comorbidity between epilepsy and PNES, a condition leading to "dual diagnosis," is a serious diagnostic and therapeutic challenge for clinicians. The lack of prompt identification of PNES in epileptic patients can lead to potentially harmful increases in the dosage of anti-seizure drugs (ASD) as well as erroneous diagnoses of refractory epilepsy. Hence, pseudo-refractory epilepsy is the other critical side of the PNES coin as one out of four to five patients admitted to video-EEG monitoring units with a diagnosis of pharmaco-resistant epilepsy is later found to suffer from non-epileptic events. The majority of these events are of psychogenic origin. Thus, the diagnostic differentiation between pseudo and true refractory epilepsy is essential to prevent actions that lead to unnecessary treatments and ASD-related side effects as well as produce a negative impact on the patient's quality of life. In this article, we review and discuss recent evidence related to the neurobiology of PNES. We also provide an overview of the classifications and diagnostic steps that are employed in PNES management and dwell on the concept of pseudo-resistant epilepsy.

Terminology for psychogenic nonepileptic seizures: Making the case for "functional seizures"

PURPOSE

The purpose of the study was to review the literature on the terminologies for psychogenic nonepileptic seizures (PNES) and make a proposal on the terminology of this condition. This proposal reflects the authors' own opinions.

METHODS

We systematically searched MEDLINE (accessed from PubMed) and EMBASE from inception to October 10, 2019 for articles written in English with a main focus on PNES (with or without discussion of other functional neurological disorders) and which either proposed or discussed the accuracy or appropriateness of PNES terminologies.

RESULTS

The search strategy reported above yielded 757 articles; 30 articles were eventually included, which were generally of low quality. "Functional seizures" (FS) appeared to be an acceptable terminology to name this condition from the perspective of patients. In addition, FS is a term that is relatively popular with clinicians.

CONCLUSION

From the available evidence, FS meets more of the criteria proposed for an acceptable label than other popular terms in the field. While the term FS is neutral with regard to etiology and pathology (particularly regarding whether psychological or not), other terms such as "dissociative", "conversion", or "psychogenic" seizures are not. In addition, FS can potentially facilitate multidisciplinary (physical and psychological) management more than other terms. Adopting a universally accepted terminology to describe this disorder could standardize our approach to the illness and facilitate communication between healthcare professionals, patients, their families, carers, and the wider public.

Semiological classification of psychogenic nonepileptic seizures: A systematic review and a new proposal

PURPOSE

A semiological classification of psychogenic nonepileptic seizures (PNES) may help address proper diagnosis and management and also provide standardization for future studies. The aim of the current paper was to systematically review the literature on the proposed classification systems for the semiology of PNES and to provide a new proposal based on the best available evidence.

METHODS

I searched the electronic database PubMed on May 16, 2019 for articles that included the following search terms: "psychogenic" AND "semiology" or "classification" and also "nonepileptic" AND "semiology" or "classification" and also "pseudoseizure" AND "semiology" or "classification" since 1940. I applied the same methodology using the electronic database Scopus, though I limited the search to the title, abstract, and keywords.

RESULTS

I could identify 15 classification systems through this search strategy using the electronic database PubMed. Searching the Scopus did not yield any additional relevant papers.

CONCLUSION

I proposed a new semiological classification system for PNES based on this systematic review. This includes three major classes of motor seizures, nonmotor seizures, and mixed semiology. A universally accepted and appropriate semiological classification system for PNES may lead to better standardization of future studies and may also help in better understanding of the pathophysiological basis of this condition.