What do we know about non-epileptic seizures in adults with intellectual disability: A narrative review

Psychogenic non-epileptic (functional) seizures in adults with intellectual disability and epilepsy: A matched case-control study

OBJECTIVE

To describe the characteristics of psychogenic non-epileptic (functional) seizures (PNES) in adults with epilepsy and intellectual disability (ID) and to establish differences and risk factors regarding psychosocial functioning between individuals with and without PNES.

METHODS

Adults with ID and epilepsy living in epilepsy care facilities in The Netherlands were screened for PNES by a neurologist. A control group consisting of people with epilepsy and ID, without PNES, was matched according to age, sex, and level of ID. Objective data were retrieved retrospectively from clinical notes of the resident. Standardized questionnaires and tests, adjusted for people with ID, were obtained from participants and their nursing staff. Differences were analyzed using paired t tests, Wilcoxon signed-rank tests, or McNemar's tests, appropriate for matched case-control studies. Conditional logistic regression identified PNES risk factors.

RESULTS

Five hundred forty individuals were screened, of which 42 had PNES (point prevalence 7.8%). In total, 35 cases and 35 controls gave consent. Proxy reports indicated that PNES impacted daily life in 79% by adjusting the individual's schedule, and caused minor injuries in one-third. Those with PNES were mainly female (69%); had a mild (46%) or moderate (37%) level of ID; showed more symptoms of depression (p = .024), anxiety (p = .030), self-injurious behavior (p = .015); and experienced more negative life events (p < .001). Clinically relevant predictors of PNES were the number of negative life events (odds ratio [OR] 1.71, 95% confidence interval [CI] 1.12-2.53) and self-injurious behaviors (OR 5.27, 95% CI .97-28.81).

SIGNIFICANCE

Previously, PNES in individuals with ID and epilepsy were described mainly as a reinforced behavioral pattern, due to limited associations with psychiatric disorders. Our results demonstrate that this population does show individual psychosocial vulnerabilities when measured with instruments adjusted for this population, as indicated by proxy reports from daily caregivers. Viewing PNES as an involuntary response, especially for stress-prone individuals with ID, could reduce stigma and improve treatment.

Psychogenic non-epileptic seizures in individuals with intellectual disability/borderline cognitive function: Characterization through a comparison study

PURPOSE

We set out to characterize psychogenic non-epileptic seizures (PNES) in individuals with either intellectual disability (ID) or borderline intellectual function (BIF) in comparison to those with normal cognitive function. We aimed to identify differences between the two groups to improve clinical management protocols.

METHODS

We conducted a retrospective, observational, single-center study. The medical records of individuals (aged ≥ 14 years) diagnosed with PNES, confirmed through video-electroencephalography (vEEG) at a specialized epilepsy center between January 2008 and December 2021, were reviewed. We restricted our study to individuals who underwent comprehensive neuropsychological evaluations. Furthermore, demographic, clinical, and neuropsychological data with potential prognostic indicators, alongside the reevaluation of vEEG recordings were studied. We compared two study groups based on intelligence quotient (IQ): individuals without ID (IQ≥85; n = 25) and those with either mild ID or BIF (n = 25).

RESULTS

No statistically significant clinical differences were observed between the two groups. Individuals with mild ID/BIF didn't show a longer diagnostic delay, and the prescription of inappropriate antiseizure medications (ASMs) was comparable in both cohorts. Most individuals with mild ID/BIF were treated with behavioral psychotherapeutic approaches with similar outcomes in both subgroups.

CONCLUSIONS

Individuals with mild ID/BIF and PNES don't differ in clinical management. Demographic and clinical data, as well as semiology, were comparable to those of individuals with normal cognitive function. Cognitive behavioral therapy (CBT) appears to be an effective treatment approach for individuals with and without mild ID/BIF. Further studies are needed to validate and ascertain their possible applicability in individuals with moderate/severe ID.

Medical and psychiatric comorbidities, somatic and cognitive symptoms, injuries and medical procedure history in patients with functional seizures from a public and a private hospital

PURPOSE

Patients with functional seizures (FS), otherwise known as psychogenic non-epileptic seizures (PNES), from different socioeconomic backgrounds may differ, however, this remains a gap in current literature. Comorbidities can play both a precipitating and a perpetuating role in FS and are important in the planning of individual treatment for this condition. With this study, we aimed to describe and compare the reported medical and psychiatric comorbidities, injuries, somatic and cognitive symptoms, and medical procedures among patients with FS from a private and a public epilepsy monitoring unit (EMU) in Cape Town, South Africa.

METHODS

This is a retrospective case-control study. We collected data on the comorbidity and medical procedure histories, as well as symptoms and clinical signs reported by patients with video-electroencephalographically (video-EEG) confirmed FS without comorbid epilepsy. We used digital patient records starting with the earliest available digital record for each hospital until the year 2022.

RESULTS

A total of 305 patients from a private hospital and 67 patients from a public hospital were included in the study (N = 372). Public hospital patients had higher odds of reporting intellectual disability (aOR=15.58, 95% CI [1.80, 134.95]), circulatory system disease (aOR=2.63, 95% CI [1.02, 6.78]) and gait disturbance (aOR=8.52, 95% CI [1.96, 37.08]) compared to patients with FS attending the private hospital. They did, however, have fewer odds of reporting a history of an infectious or parasitic disease (aOR=0.31, 95% CI [0.11, 0.87]), respiratory system disease (aOR=0.23, 95% CI [0.06, 0.82]), or medical procedures in the past (aOR=0.32, 95% CI [0.16, 0.63]).

CONCLUSION

The study presents prevalence and comparative data on the medical profiles of patients with FS from different socioeconomic backgrounds which may inform future considerations in FS diagnosis and treatment.

Using Semiology to Classify Epileptic Seizures vs Psychogenic Nonepileptic Seizures: A Meta-analysis

Background and objectives:

Misdiagnosis of psychogenic nonepileptic seizures (PNES) and epileptic seizures (ES) is common. In the absence of the diagnostic gold standard (video EEG), clinicians rely on semiology and clinical assessment. However, questions regarding the diagnostic accuracy of different signs remain. This meta-analysis aims to evaluate the diagnostic accuracy of semiology in PNES and ES.

Methods:

We systematically searched PubMed, PsycInfo and Medline for original research publications published before 8 February 2021 with no restriction on search dates to identify studies that compared semiology in ES and PNES in epilepsy monitoring units. Non-English publications, review articles, studies reporting on only PNES or ES and studies limited to patients with developmental delay were excluded. Study characteristics and proportions of ‘event groups’ and ‘patient groups’ demonstrating signs were extracted from each article. Bivariate analysis was conducted, and data were pooled in a random effects model for meta-analysis. The I2 statistic was calculated to assess statistical heterogeneity. The QUADAS-2 tool was utilized to assess risk of bias in included studies. The positive likelihood ratio (PLR) and negative likelihood ratio (NLR) were calculated. A PLR > 10 or an NLR < 0.1 has a large impact on the post-test probability of a diagnosis (ES or PNES) whereas a PLR between 5-10 or an NLR between 0.1- 0.2 has a moderate impact on the post-test probability of a diagnosis (ES or PNES).

Results:

The meta-analysis included 14 studies comprising of 800 patients with ES and 452 patients with PNES. For PNES, ictal eye closure (PLR 40.5 95%CI: 16.2-101.3; I2 = 0, from three studies) and asynchronous limb movements (PLR 10.2; 95%CI: 2.8-37.7; I2 = 0, from three studies) reached a PLR threshold > 5. No single sign reached a PLR threshold >5 for ES.

Conclusions:

While all signs require interpretation in the overall clinical context, the presence of ictal eye closure and asynchronous limb movements are reliable discriminative signs for PNES.

Functional Neurological Symptom Disorder in Williams Syndrome: Case Series and Review of Relevant Literature

BACKGROUND

Williams syndrome (WS) is a neurodevelopmental disorder associated with several medical and psychiatric comorbidities.

OBJECTIVE

To describe the clinical presentation and treatment course of functional neurological symptom disorder (FNSD) in 3 adult patients with WS.

METHODS

This report describes the clinical presentation and long-term follow-up of 3 individuals with WS and FNSD who experienced a range of clinical presentations and responses to treatment. The literature on the clinical assessment and treatment of FNSD as it applies to patients with neurodevelopmental disorders is reviewed.

RESULTS

FNSD treatment strategies used in the general population were successfully adapted for these 3 patients. Literature on the diagnosis and treatment of FNSD in patients with neurodevelopmental disorders is lacking.

CONCLUSIONS

FNSD may be more common in individuals with WS than previously appreciated, and future studies describing the prevalence, clinical presentation, risk factors, and treatment of FNSD in WS are needed.