Sleep in psychogenic nonepileptic seizures and related disorders

Functional seizures and their mimics: a retrospective service review of cases from a tertiary video telemetry database

ABSTRACT

Objective

Identify the proportion of patients referred with putative functional seizures (FS) that were subsequently re-diagnosed as epileptic seizures (ES), or an alternative diagnosis, following video telemetry EEG (VTEEG). In addition, describe the characteristics of those seizures.

Methods

The VTEEG reports from patients admitted to the Chalfont Centre for Epilepsy between 2019 and 2022 were reviewed. Pre-VTEEG and post-VTEEG diagnoses were compared to identify whether a diagnostic revision was made from suspected FS to ES or another diagnosis. Diagnostic revision cases were then grouped into cohorts with associated features and reviewed to characterise and describe FS mimics.

Results

444 VTEEG reports where patients had habitual events were identified. 4.7% of patients were referred with FS and were subsequently diagnosed with ES or another diagnosis. In this group, several cohorts could be identified including frontal lobe epileptic seizures, ES with functional overlay, insular or temporal lobe epileptic seizures associated with autonomic or marked experiential peri-ictal symptoms, and individuals who had both ES and FS but whose ES were revealed on medication withdrawal.

Conclusion

In patients referred to a tertiary epilepsy unit, a small minority of cases had seizures diagnosed as functional and reclassified as epileptic or an alternative diagnosis. It is clinically important to be aware of these FS mimics.

The neurobiology of functional neurological disorders characterised by impaired awareness

We review the neurobiology of Functional Neurological Disorders (FND), i.e., neurological disorders not explained by currently identifiable histopathological processes, in order to focus on those characterised by impaired awareness (functionally impaired awareness disorders, FIAD), and especially, on the paradigmatic case of Resignation Syndrome (RS). We thus provide an improved more integrated theory of FIAD, able to guide both research priorities and the diagnostic formulation of FIAD. We systematically address the diverse spectrum of clinical presentations of FND with impaired awareness, and offer a new framework for understanding FIAD. We find that unraveling the historical development of neurobiological theory of FIAD is of paramount importance for its current understanding. Then, we integrate contemporary clinical material in order to contextualise the neurobiology of FIAD within social, cultural, and psychological perspectives. We thus review neuro-computational insights in FND in general, to arrive at a more coherent account of FIAD. FIAD may be based on maladaptive predictive coding, shaped by stress, attention, uncertainty, and, ultimately, neurally encoded beliefs and their updates. We also critically appraise arguments in support of and against such Bayesian models. Finally, we discuss implications of our theoretical account and provide pointers towards an improved clinical diagnostic formulation of FIAD. We suggest directions for future research towards a more unified theory on which future interventions and management strategies could be based, as effective treatments and clinical trial evidence remain limited.

Sleep Disturbances in Patients with Nonepileptic Seizures

OBJECTIVE

Up to 20% of patients treated for epileptic seizures experience psychogenic nonepileptic paroxysms (PNES). These patients present a significant burden for the health care systems because of poor treatment outcomes. The presented review aims to summarize the current state of knowledge on sleep disturbances in patients with nonepileptic seizures.

METHODS

Articles were acquired via PubMed and Web of Science, and papers between January 1990 and March 2020 were extracted. Inclusion criteria were (1) published in a peer-reviewed journal: (2) studies in humans only; or (3) reviews on a related topic; (4) English language. The exclusion criteria were: (1) abstracts from conferences; (2) commentaries; (3) subjects younger than 18 years. From primary assessment, 122 articles were extracted; after obtaining full texts and secondary articles from reference lists, 45 papers were used in this review.

RESULTS

Limited data are available regarding sleep disorders in PNES patients, over the last 30 years only nine original research papers addressed sleep problems in patients with PNES with only six studies assessing objectively measured changes in sleep. Current literature supports the subjective perception of the sleep disturbances with mixed results in objective pathophysiological findings. Conflicting results regarding the REM phase can be found, and studies reported both shortening and prolonging of the REM phase with methodological limitations. Poor sleep quality and shortened duration have been consistently described in most of the studies.

CONCLUSION

Further research on a broader spectrum of patients with PNES is needed, primarily focusing on objective neurophysiological findings. Quality of life in patients suffering from PNES can be increased by good sleep habits and treatment of comorbid sleep disorders.

Atypical Prodromal Symptoms Help to Distinguish Patients With Psychogenic Nonsyncopal Collapse Among Youth Referred for Fainting

BACKGROUND

Distinguishing patients with psychogenic nonsyncopal collapse (PNSC), a conversion disorder that resembles syncope, can pose a difficult clinical challenge. Using the open-ended question "what does it feel like to faint?," the present study aimed to characterize how patients with PNSC perceive and communicate the prodromal symptoms associated with their attacks by comparing narratives between patients with PNSC and those with syncope.

METHODS

During a 42-month database-type study of tilt-table diagnoses, all patients with a history of fainting were asked the open-ended question. Symptom descriptions were compared, qualitatively and quantitatively, between patients with PNSC and those with tilt-induced syncope (n = 121 in both cohorts).

RESULTS

Twenty-nine patients (24%) diagnosed with PNSC and eight (6.6%) diagnosed with syncope either denied having any prodromal symptoms or could not recall any symptoms (P < 0.001). Among patients who reported prodromal symptoms, patient narratives led to the formation of 26 symptom categories. Symptom frequencies differed between cohorts in 19 of the symptom categories (each P value <0.05). Qualitative differences in the descriptions of symptoms were often present, even when symptom frequencies did not differ. More patients with PNSC described atypical symptoms than patients with syncope, 54 of 92 (58.7%) versus eight of 113 (7.1%), P < 0.001.

CONCLUSIONS

Symptom narratives can help to distinguish patients with PNSC from those with syncope. The use of a single, open-ended question as a screening tool for conversion disorder has immediate clinical relevance because it can be instituted easily in a busy clinical setting.

Sleep in psychogenic nonepileptic seizures: Time to raise a red flag

Poor sleep is a frequent complaint in patients with psychogenic nonepileptic seizures (PNES). However, few studies have examined sleep problems in this population. We aimed to compare sleep complaints in patients with PNES with those with epilepsy. Subjects diagnosed as having PNES by experts using video-electroencephalography (vEEG) were recruited through the Brigham and Women's Hospital epilepsy monitoring unit (EMU) between 3/25/2013 and 3/29/2018. Controls were patients with epilepsy recruited through the EMU and subspecialty clinics. All subjects were given the Beck Depression Inventory, 2nd Edition (BDI-II) and the Quality of Life in Epilepsy Inventory-10 (QOLIE-10). Subjective sleep problems were identified from item 16 (changes in sleep patterns) of the BDI-II. Independent sample t-test, chi-square test, and Spearman correlation were used. A total of 149 patients with PNES and 82 patients with epilepsy completed the BDI-II and QOLIE-10. Compared with control subjects with epilepsy, patients with PNES more frequently reported moderate-severe changes in sleep patterns, notably sleeping less than usual, waking up 1-2 h too early, and having trouble returning to sleep. These changes in sleep patterns were associated with worse quality of life. Our findings suggest that sleep is more commonly reported as a problem in PNES compared with epilepsy. Because sleep plays a major role in good health, understanding the specific sleep problem in PNES may provide insight for improving quality of life for this challenging disorder.