How variable are psychogenic nonepileptic seizures? A retrospective semiological study

Functional seizures: Are they consistent over time?

BACKGROUND

Our previous study showed that functional seizures (FS) are consistent in the same patient during a single video EEG monitoring (VEEG). This study aimed to check whether FS remains consistent across VEEG sessions even after several years.

METHODS

The study evaluated the consistency of FS across different VEEG sessions using five criteria: FS type, the main anatomical region involved (specifically, the body part most affected during the seizure), other involved anatomical regions, frequency of movements, and duration of FS. Consistency levels were categorized as low (one consistent axis), moderate (two consistent axes), and high (three or more consistent axes).

RESULTS

Fourteen patients were included in the final analysis. The mean time between monitoring was 3.8 ± 2.5 years (0.5-8 year). In 13 of 14 patients, the first and second monitoring events were classified into the same FS category. There was consistency in the main anatomical region involved in 9 out of 12 patients with motor FS. In 9 out of 12 patients with motor FS, the other anatomical regions involved were consistent in both sessions. The mean duration of the FS between sessions was inconsistent in most of the patients. Ten patients were classified with high consistency, one patient with moderate consistency, two patients with low consistency, and in one patient, the events were classified as inconsistent.

CONCLUSIONS

Our results show that FS tends to remain consistent in a single patient even after several years, and there is probably no correlation between the degree of consistency and the time between VEEG sessions. These findings have implications for supporting the concept of FS as a consistent phenomenon. Additionally, they may suggest potential avenues for future research to elucidate the origins of FS. Subsequent studies are essential to validate and expand upon these preliminary observations.

The Comparison Between Neuropsychological Features of Psychogenic Non-epileptic Seizures and Epileptic Seizures

Background: Both epileptic seizures (ES) and psychogenic non-epileptic seizures (PNES) are often associated with some degree of cognitive impairment. Video electroencephalography (EEG) monitoring is the gold standard for diagnosing PNES. This diagnostic procedure is costly and available in specific tertiary centers. Neuropsychological assessment can provide clues for the differential diagnosis of PNES and ES and help clarify the nature and etiology of these two disorders. Objectives: Therefore, this study aimed to compare the neuropsychological profiles of PNES and ES patients. Methods: In this analytical cross-sectional study, 30 patients with ES and 31 patients with PNES were compared by neuropsychiatric tests, such as the Wechsler Adult Intelligence scale (WAIS), Addenbrooke’s Cognitive examination (ACE), and California Verbal Learning test (CVLT). Results: There was a female predominance in the PNES group (female-to-male ratio = 4.16/1, P = 0.003). In the PNES group, 77.4% of the patients had a psychiatric disorder versus 66.7% of the patients in the ES group; however, the difference was not statistically significant (P = 0.34). The mean score of total intelligence was higher in the PNES group (84.77 ± 16.94), compared to the ES group (83.63 ± 10.04); however, the difference was not significant (P = 0.75). Based on the mean subscale scores, the digit symbol score (WAIS-IV subscale) and memory score (ACE subscale) were significantly higher in the PNES group compared to the ES group (P = 0.037 and 0.032, respectively). Conclusions: This study showed that neuropsychological assessments might not differentiate ES from non-epileptic seizures.

Long-Term V-EEG in Epilepsy: Chronological Distribution of Recorded Events Focused on the Differential Diagnosis of Epileptic Seizures and Psychogenic Non-Epileptic Seizures

Differential diagnosis in epilepsy is sometimes challenging. Video-electroencephalography (V-EEG) is an essential tool in the diagnosis and management of epilepsy. The prolonged duration of V-EEG recording increases the diagnostic yield of a conventional V-EEG. The right length of monitoring for different indications is still to be established. We present a retrospective descriptive study with a sample of 50 patients with long-term V-EEG monitoring, with a mean age of 36.1 years, monitored from 2013 to 2019 at the Burgos University Hospital. The mean monitoring time was 3.6 days. Events were obtained in 76% of the patients, corresponding to epileptic seizures (ES) in 57.9% of them, with psychogenic non-epileptic seizures (PNES) in 39.5%, and with episodes of both pathologies in 2.6% of the patients. We found that the first event was highly representative, and it correlated with the rest of the events that would be recorded. Moreover, 92% of the first PNES had been captured at the end of the second day, and 89% of the first ES by the end of the third day. V-EEG for differential diagnosis between ES and PNES can be performed in hospitals without specialized epilepsy surgery units. For this indication, the duration of long-term V-EEG can be adjusted individually depending on the nature of the first event.

A descriptive study of patients diagnosed with psychogenic nonepileptic seizures at a tertiary epilepsy center in the Czech Republic: One-year follow-up

PURPOSE

To delineate sociodemographic data of a large sample of Czech Republic patients diagnosed with psychogenic non-epileptic seizures (PNES) at the time of diagnosis and at a follow-up visit one year after discharge. This study collected reports of past stressors, quality of relationships in childhood, family background, traumatic events, and recent adversities in patients diagnosed with PNES.

METHOD

Patients (219w/79m, 37.56 (13.15) years, 12.13 (2.05) years of education) were assessed through a semi-structured interview on clinical and historical data while they were inpatients at the Epilepsy Center, Na Homolce Hospital, Prague. Subsequently, they were re-evaluated one year after discharge from the hospital with the same method. A comparison of this sample to normal controls was subsequently conducted.

RESULTS

We found a higher female (73.5%) predominance; mean duration of seizures was 69.14 months. The majority of patients were single (46.13%) or divorced (16.84%), and 48% received disability benefits. A diversity of developmental risk factors as well as immediate precursors of PNES onset were identified. One year after hospitalization, significant changes were found in all seizure and healthcare characteristics of our sample. When compared to healthy volunteers, the patients also presented with a higher prevalence of stressors and traumatic events in childhood.

CONCLUSIONS

Cross-cultural research contributes important information on the universal components of PNES as well as the unique features observed in distinct localities of differing cultures and ethnicities. This study allows for comparison of sociodemographic features in a Central European sample to the more frequently studied English-speaking samples.

Classification and comparative analysis of psychogenic nonepileptic seizures (PNES) semiology based on video-electroencephalography (VEEG)

BACKGROUND

Multiple classification systems for psychogenic nonepileptic seizures (PNES) based on semiological features have been described. We sought to compare the efficiency of four PNES classification systems.

METHODS

We retrospectively analyzed medical and video-electroencephalography (VEEG) records of patients with PNES with at least one typical event recorded on VEEG. Semiology of PNES events was stringently classified using Hubsch, Dhiman, Wadwekar, and Asadi-Pooya's classification systems.

RESULTS

We studied 248 patients with PNES (78% females, mean age 23.1 ± 10.3 years) and reviewed 498 PNES events. Using Hubsch's scheme, we classified events into: dystonic attacks with primitive gestural activity (5.2%), paucikinetic attacks with preserved responsiveness (9.7%), pseudosyncope (59.8%), hyperkinetic prolonged attacks (16.2%) and axial dystonic prolonged attacks (1.6%), and unclassified (7.5%). Using Dhiman's classification, events were: abnormal motor (hypermotor [10.4%]/ partial motor [12.7%]), dialeptic type (58.6%), mixed patterns (17.3%), and unclassified (1%). Using Wadwekar's classification: dystonic attacks with primitive gestural activity (5.2%), paucikinetic attacks with preserved responsiveness (9.6%), pseudosyncope with/without hyperventilation (65.1%), hyperkinetic prolonged attacks involving limbs ± trunk (18.5%), and axial dystonic prolonged attacks (1.6%). Using Asadi-Pooya's classification, events were: hypermotor (30.1%), non-motor (62.9%), and mixed (7.0%). All events could be classified via Wadwekar and Asadi-Pooya systems.

CONCLUSION

In our study, pseudosyncope/dialeptic/non-motor semiology emerged as most frequent. Most of our patients with PNES had stereotyped semiology. All events could be classified using the schemes by Asadi-Pooya and Wadweker et al. Dhiman et al. scheme could classify 99% and 7.5% remained unclassified using Hubsch et al. scheme.

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.

Differential diagnosis between epileptic seizures and psychogenic nonepileptic seizures based on semiology

Psychogenic nonepileptic seizures present as paroxysmal symptoms and signs mimicking epileptic seizures. The gold standard test is the synchronous recording by video, electrocardiogram and electroencephalogram. However, video electroencephalogram is not available at many centers and not entirely independent of semiology. Recent studies have focused on semiological characteristics distinguishing these two circumstances. Clinical signs and symptoms provide important clues when making differential diagnosis. The purpose of this review is to help physicians differentiating psychogenic nonepileptic seizures better from epileptic seizures based on semiology, and improve care for those patients.

Reliability of reported peri-ictal behavior to identify psychogenic nonepileptic seizures

PURPOSE

Differentiating psychogenic non-epileptic seizures (PNES) from epileptic seizures (ES) can be difficult, even when expert clinicians have video recordings of seizures. Moreover, witnesses who are not trained observers may provide descriptions that differ from the expert clinicians', which often raises concern about whether the patient has both ES and PNES. As such, quantitative, evidence-based tools to help differentiate ES from PNES based on patients' and witnesses' descriptions of seizures may assist in the early, accurate diagnosis of patients.

METHODS

Based on patient- and observer-reported data from 1372 patients with diagnoses documented by video-elect roencephalography (vEEG), we used logistic regression (LR) to compare specific peri-ictal behaviors and seizure triggers in five mutually exclusive groups: ES, PNES, physiologic non-epileptic seizure-like events, mixed PNES plus ES, and inconclusive monitoring. To differentiate PNES-only from ES-only, we retrospectively trained multivariate LR and a forest of decision trees (DF) to predict the documented diagnoses of 246 prospective patients.

RESULTS

The areas under the receiver operating characteristic curve (AUCs) of the DF and LR were 75% and 74%, respectively (empiric 95% CI of chance 37-62%). The overall accuracy was not significantly higher than the naïve assumption that all patients have ES (accuracy DF 71%, LR 70%, naïve 68%, p > 0.05).

CONCLUSIONS

Quantitative analysis of patient- and observer-reported peri-ictal behaviors objectively changed the likelihood that a patient's seizures were psychogenic, but these reports were not reliable enough to be diagnostic in isolation. Instead, our scores may identify patients with "probable" PNES that, in the right clinical context, may warrant further diagnostic assessment.

A systematic study of stereotypy in epileptic seizures versus psychogenic seizure-like events

OBJECTIVE

The objective of this study was to quantify the features of stereotypy in epileptic seizures and compare it with that of stereotypy in psychogenic nonepileptic seizure-like events (PNES) confirmed by video-electroencephalography (VEEG) monitoring.

METHODS

Video-electroencephalography monitoring records of 20 patients with temporal lobe seizures (TLS) and 20 with PNES were retrospectively reviewed (n = 138 seizures, 48 TLS and 90 PNES). We analyzed the semiology of 59 behaviors of interest for their presence, duration, sequence, and continuity using quantified measures that were entered into statistical analysis.

RESULTS

We identified discontinuity as the parameter that was clearly distinct between PNES and epileptic TLS events: there were significantly more frequent pauses of behavior (i.e., "on-off" pattern) in PNES compared with TLS (P = 0.012). The frequency of pauses during an event was diagnostic of PNES events. For instance, the presence of 2 "pauses" during an episode determines a 69% probability of the seizure being nonepileptic. Moreover, PNES events had significantly greater duration (143 s) than TLS events (68 s) (excluding outliers, P = 0.002) and greater duration variability from one event to another in the same subject (P = 0.005).

SIGNIFICANCE

Our work provides the first quantified measure of behavioral semiology during epileptic and nonepileptic seizures and offers novel behavioral measures to differentiate them from each other.

Semiological characteristics of patients with psychogenic nonepileptic seizures: Gender-related differences

Psychogenic nonepileptic seizures (PNES) are more prevalent among women, and diagnosis may sometimes be delayed by as much as seven years. Understanding the effect of gender on the presentation of a PNES may assist with diagnosis based on semiological details in the clinical setting. Although video-EEG monitoring (VEM) is the gold standard for diagnosing PNES, determining gender-related seizure semiology through careful history may prevent diagnostic delay while waiting for VEM. The aim of this study was to investigate gender-related differences in the semiology of PNES. Patients, all aged at least 16 years, diagnosed with PNES following VEM between December 2005 and November 2016 were included in this study. All patients' medical records and video-EEG-documented PNES were reviewed, and the presence or absence of semiological signs was recorded for each documented attack. Demographic features and semiological signs of PNES were compared between female and male patients. Forty-one patients (31 females, 10 males) aged 27.2 ± 12.2 years (range: 16-65) were included in the study. Mean age at onset of PNES was higher for female patients than males, at 24.3 ± 11.5 versus 17.5 ± 3.2 years (p = 0.005). The median duration of PNES was longer for female patients than males, at 10 min (range: 5 s-120 min) versus 2 min (range: 10 s-60 min) (p = 0.016). The most common symptom was forced eye closure in both genders. No significant gender-specific differences were observed in terms of the type or semiology of PNES. Although there are no major gender-related differences in PNES semiology, our findings highlight the importance of greater caution, especially in male patients, when diagnosing PNES, remembering that onset may also occur at young ages and that a short seizure duration does not exclude PNES.

Characteristics of patients with confirmed epilepsy and psychogenic nonepileptic seizures in Qatar

OBJECTIVE

The Middle Eastern country of Qatar opened its first epilepsy monitoring unit (EMU) in late 2015. This study compared demographic and clinical characteristics of patients with confirmed epilepsy to those of patients with confirmed psychogenic nonepileptic seizures (PNES).

METHODS

Data were collected via retrospective chart review on 113 patients admitted for evaluation to the Qatar national health system EMU between November 2015 and May 2017.

RESULTS

Seventy-one patients had a confirmed diagnosis (20 had PNES, 46 had epilepsy, 5 had both PNES and epilepsy). Evaluation in 33 patients was inconclusive, and 9 had other medical conditions. Patients with PNES were significantly more likely to be primary Arabic speakers (p = 0.003), and this difference was not explained by education or employment status. The most common referral request in patients with PNES was for recurrent/refractory seizures (p = 0.011), and there was a trend for patients with PNES to have more frequent seizures compared with patients with epilepsy (daily to several per week versus several times a month or less, p = 0.051). Depression was identified in 47% of patients with epilepsy and 65% of patients with PNES, and patients with PNES had higher mean depression scores on the PHQ-9 than patients with epilepsy (p = 0.014). Patients with PNES experienced significantly more fatigue (p = 0.021). Seventy percent of patients with PNES and 50% of patients with epilepsy reported sleep problems.

CONCLUSIONS

The characteristics of patients with epilepsy and PNES at the EMU in Qatar were generally similar to those found worldwide. Patients with PNES more often suffered from frequent depression, sleep problems, and fatigue than those with epilepsy, but these were significant concerns for both groups.

Are the clinical classifications for psychogenic nonepileptic seizures reliable?

BACKGROUND

Psychogenic nonepileptic seizures (PNESs) are episodes that resemble epileptic seizures but are of psychological origin. A few studies have attempted to describe different types of PNES as a combination of clinical signs but their validation and robustness have not yet been reached. The aim of this study was to assess the inter-rater reliability (IRR) of five existing clinical PNES classifications.

METHODS

A total of 107 PNESs from 54 patients were retrospectively analyzed independently by two trained epileptologists, who were blinded to each other's findings. The recorded events were grouped according to the five chosen classifications systems. The IRR was measured using a kappa (κ) coefficient for each PNES classification. We also report category-specific κ values.

RESULTS

Our study demonstrated a mild to moderate IRR (κ from 0.44-0.68) for classifying PNES using the 5 proposed classification schemes. Within these classifications, the most reproducible classes are the subjective ones followed by the dialeptic group. Classes based on motor signs are the least reproducible.

CONCLUSION

The IRR for current clinical classifications of PNES was only moderate. The difficulty to analyze motor signs could explain this poor reliability. It is necessary to ensure the reliability of clinical classifications of PNES in order for them to be a relevant tool in clinical practice or to explore correlations in clinical research. Future research would benefit from increased precision of diagnostic criteria specific to each class.

Semiology of psychogenic nonepileptic seizures: An international cross-cultural study

PURPOSE

We compared the semiology of psychogenic nonepileptic seizures (PNES) between patients from the USA and Brazil. This international cross-cultural comparative study may expand understanding of PNES across the borders.

METHODS

We retrospectively investigated all patients with PNES admitted to one epilepsy center in the USA and one in Brazil. We classified their seizures into four classes: generalized motor, akinetic, focal motor, and subjective symptoms. All patients were interviewed by an epileptologist in both countries and were administered psychological assessment measures, including questions about PNES risk factors. For the statistical analyses, we compared patients from the two nations.

RESULTS

Eighty-nine patients (49 from the USA and 40 from Brazil) were studied. Patients from the two countries were not significantly different with regard to sex and age, but patients from Brazil had earlier age at onset (26years vs. 34years; P=0.004) and a significantly greater delay in diagnosis (9.9years vs. 5.6years; P=0.001). Some characteristics of PNES were different between the two groups; patients from the USA had generally more seizure types and more often reported subjective seizures (55% in the USA vs. 10% in Brazil; P=0.0001). Clinical and historical characteristics of the patients were not significantly different.

CONCLUSION

Delay in diagnosis of PNES may represent a major factor in resource-limited countries. Large multicenter cross-cultural studies may reveal subtle but significant cross-cultural differences with respect to the semiological, clinical, and historical aspects of PNES; however, patients with PNES share more similarities than differences.

Delay in diagnosis of psychogenic nonepileptic seizures in adults: A post hoc study

PURPOSE

The aim of the current post hoc study was to investigate factors associated with delay in diagnosis of adult patients with psychogenic nonepileptic seizures (PNES).

METHODS

We retrospectively investigated all patients with PNES admitted to the epilepsy-monitoring unit at the Jefferson Comprehensive Epilepsy Center from 2012 through 2016. We identified the median time to diagnosis of PNES and divided the patients into two groups. We studied factors associated with delay in diagnosis of PNES.

RESULTS

In all, 49 patients (39 women and 10 men) were studied. Mean age at the time of admission was 40±16years and at the onset of the seizures was 34±16years. Disease duration was 5.6±8.2years. The median for time to diagnosis was 3years. Patients with early diagnosis (before 3years after seizure onset) (21 patients) and patients with late diagnosis (delay of 3years or more from onset) (28 patients) were compared. Only history of head trauma had significant association with the delay in diagnosis: 2 of 19 patients (7%) with an early diagnosis and 11 of 28 patients (39%) with a late diagnosis reported head trauma (P=0.02).

CONCLUSION

Delay in diagnosis of PNES is common, and some factors (e.g., history of head trauma) may contribute to this delay. It is important that physicians involved in the management of seizures appreciate the importance of making an early and definitive diagnosis of PNES.