Neurocognitive Effects of Antiseizure Medications in Children and Adolescents with Epilepsy

Disproportionality analysis of the safety profile of rufinamide in the real world: an evaluation of the FDA Adverse Event Reporting System database

BACKGROUND

Rufinamide (RUF) is an antiepileptic drug recently introduced for managing seizures in Lennox-Gastaut syndrome (LGS), but its adverse reactions are not well understood. This study aims to evaluate RUF's safety profile using data from the FDA Adverse Event Reporting System (FAERS).

METHODS

Disproportionality analysis was conducted to assess RUF-associated adverse drug events (ADEs), using reporting odds ratio (ROR), proportional reporting ratio (PRR), Bayesian confidence propagation neural network (BCPNN), and multi-item gamma-Poisson shrinker (MGPS).

RESULTS

We collected 338 ADE reports related to RUF. Nervous system disorders were the most frequently reported signals, and several new ADEs were detected, including atonic seizures, sudden unexplained death in epilepsy, seizure clusters, multi-drug resistance, and Stevens-Johnson syndrome. Nearly half of the ADEs in pediatric patients were psychological or neurological. Disproportionality analysis within 4 weeks of treatment showed high RORs for QT shortening, sudden death, and atonic seizures.

CONCLUSIONS

Our study revealed prospective signals of new ADEs linked to RUF as well as revealed that both prescribers and patients were more conscious of the risks involved in its clinical use.

Practical considerations for the use of fenfluramine to manage patients with Dravet syndrome or Lennox-Gastaut syndrome in clinical practice

Fenfluramine (FFA), an antiseizure medication (ASM) with serotonergic and sigma-1 receptor activity, is used to manage patients with developmental and epileptic encephalopathies (DEEs). It is approved in the US for treating seizures associated with Dravet syndrome (DS) and Lennox-Gastaut syndrome (LGS) in patients ≥2 years old and as add-on therapy for seizures associated with DS and LGS in the EU, UK, and Japan in similarly aged patients. Consensus guidelines for treatment of DS have recommended FFA to be an early-line ASM, and it has also shown efficacy in managing seizures associated with LGS. DS and LGS are DEEs associated with a range of seizure types, developmental impairments, and multiple comorbidities. Here we provide case vignettes describing 4 patients (3 DS and 1 LGS) aged 4-29 years old in whom up to 14 ASMs had previously failed, to illustrate real-world practice issues encountered by neurologists. This review provides guidance on the use of FFA in the context of ASM polytherapy and drug-drug interactions (DDIs), behavioral issues, dose titration, and adverse events. Along with data from the clinical trial program, these case vignettes emphasize the low risk of DDIs, a generally well-tolerated safety profile, and other seizure and nonseizure benefits (eg, improved cognition and sleep) associated with the use of FFA in DS or LGS. PLAIN LANGUAGE SUMMARY: Fenfluramine is used to treat seizures in individuals with Dravet syndrome and Lennox-Gastaut syndrome, but there are a range of issues that clinicians may face when treating patients. This review highlights four patients from the authors' everyday clinical work and offers guidance and practical considerations by neurologists with expertise in managing these complex conditions related to drug interactions, dosing, and side effects associated with fenfluramine.

Lamotrigine for cognitive deficits associated with neurofibromatosis type 1: A phase II randomized placebo-controlled trial

AIM

To find proof-of-principle evidence for short-term treatment with lamotrigine to improve cognitive functioning of adolescents with neurofibromatosis type 1 (NF1).

METHOD

This was a double-blind, parallel-group, randomized, placebo-controlled clinical trial (the NF1-EXCEL trial: Examining the Cognitive and Electrophysiological benefit of Lamotrigine in Neurofibromatosis type 1; Clinicaltrials.gov identifier NCT02256124), with the aim of enrolling 60 adolescents with NF1 aged 12 to 17  years 6 months. The short-term study intervention was 200 mg of lamotrigine taken orally for 26 weeks. The primary outcome was performance IQ tested with the Wechsler Intelligence Scale for Children, Third Edition, complemented with secondary outcomes for visuospatial learning efficacy, visual perception, visual sustained attention, fine motor coordination, attention-deficit/hyperactivity problems, and executive functioning.

RESULTS

We screened 402 adolescents with NF1, of whom 31 (eight females) entered the study. Complete-case analysis showed no effect of lamotrigine on either performance IQ (-0.23, 95% CI -6.90 to 6.44) or most secondary outcomes. Visual sustained attention showed a trend towards better performance in the lamotrigine group (-0.81, 95% CI -1.67 to 0.04).

INTERPRETATION

Lamotrigine did not improve cognitive functioning in adolescents with NF1. The small treatment effects make it unlikely that a larger sample size could have changed this conclusion.

The Effect of Levetiracetam and Valproic Acid Treatment on Anger and Attention Deficit Hyperactivity Disorder Clinical Features in Children and Adolescents with Epilepsy: A Prospective Study

BACKGROUND AND OBJECTIVE

Antiseizure medications (ASMs) can potentially trigger psychobehavioral adverse events associated with the onset or exacerbation of psychiatric symptoms such as irritability, aggression, and hyperactivity. The objective of this study was to evaluate the effects of levetiracetam and valproic acid on changes in clinical features of anger, attention deficit hyperactivity disorder (ADHD), and oppositional defiant disorder (ODD). The purpose was to furnish guidance on rational drug selection in children and adolescents with epilepsy to minimize psychiatric comorbidity in the treatment of epilepsy.

METHOD

This was a prospective, observational, cohort study involving treatment-naïve children aged 7-18 years with newly diagnosed generalized or focal epilepsy who were prescribed levetiracetam or valproic acid as monotherapy for a 6-month period and regularly followed up. Psychiatric assessment was conducted at the time of the new epilepsy diagnosis and at the six-month follow-up. These assessments were performed using the Schedule for Affective Disorders and Schizophrenia for School-Age Children Current and Lifetime Version (DSM-5), a structured psychiatric interview, as well as the State-Trait Anger Expression Style Inventory and Turgay DSM-IV Based Disruptive Behaviour Disorders Screening and Rating Scale. Anger subscores, ADHD symptoms, change in diagnosis, focal and generalized epilepsy groups, continuous seizures and seizure-free periods before and 6 months after treatment with valproic acid and levetiracetam were compared.

RESULTS

A total of 50 children, 25 in the valproic acid group and 25 in the levetiracetam group, with a mean age of 11.92 ± 3.08 years, were included in the study. There was a statistically significant increase in the ADHD subscale score post-treatment among patients receiving levetiracetam (p = 0.045) and valproic acid (p = 0.034) compared with pre-treatment. The change in both anger-in and anger-out expression scores with treatment was significantly higher in patients receiving levetiracetam (p = 0.035) compared with those receiving valproic acid (p = 0.026). Statistically, there was a significant difference in the diagnostic criteria of the levetiracetam group pre- and post-treatment (p = 0.026). The proportion of patients in whom the diagnostic criteria for ADHD+ODD were fulfilled increased from 16% before treatment to 48% after treatment, a statistically significant increase (p = 0.026).

CONCLUSION

This study found an increase in internalized anger features and ADHD symptom severity in children with epilepsy treated with valproic acid and levetiracetam. In those prescribed levetiracetam, there was a statistically significant rise in the proportion meeting the diagnostic criteria for ADHD + ODD. Our research is one of the first to prospectively examine the psychiatric assessment of children diagnosed with epilepsy. The remarkable results demonstrate changes in psychiatric diagnoses associated with the treatment of levetiracetam and valproic acid. Furthermore, a considerable rise in ADHD symptoms was observed in those treated with valproic acid.

Differential contributions of performance-based and parental reports of executive functioning on memory in pediatric focal and generalized epilepsies

Children with epilepsy often experience deficits in both executive functioning (EF) and memory. However, how these two domains interact and relate to specific epilepsy types remains unclear. This study compared two groups of children: those with localization-related epilepsy (LRE) and those with genetic generalized epilepsy (GGE). We aimed to understand how performance-based and parent-reported EF differentially contribute to understanding memory function in each group. We examined neuropsychological measures assessing memory and EF in 75 children with LRE and 91 with GGE. Multiple linear regressions explored the impact of EF on memory performance. Performance-based EF scores accounted for greater variance in memory scores than parental EF reports. However, performance-based EF measures explained much more variance in visual memory for LRE than GGE and explained much more variance in verbal memory for the GGE group. Parental reports of EF contributed marginally to understanding variance. These findings suggest differential relationships between EF and memory based on epilepsy type. Performance-based EF measures appear more reliable at understanding memory variance than did parent reports. Our results have potential clinical implications for tailoring neuropsychological assessment and intervention for children with different epilepsy types.

Off-label use of cannabidiol in genetic epileptic and developmental encephalopathies: A case report

Developmental Epileptic encephalopathies (DEEs) are severe neurological conditions where cognitive functions appear modulated by both seizure and interictal epileptiform activity. Cannabidiol (CBD) has been shown to be highly effective in the treatment of drug-resistant seizures in patients with DEEs. Along with its antiseizure effects, CBD demonstrated clinical beneficial effects in patients' quality of life, sleep and numerous adaptive behaviors. However, based on the available phase III studies, the indications for this treatment have so far been restricted to Lennox-Gastaut syndrome (LGS), Dravet syndrome (DS) and tuberous sclerosis complex (TSC) by regulatory authorities. We present the case of a 30-year-old girl with a rare genetic DEE, experiencing relevant seizure frequency reduction together with striking improvement in sleep quality, mood, behavior, language and motor skills after introducing off-label CBD.

Pharmacodynamic rationale for the choice of antiseizure medications in the paediatric population

In the landscape of paediatric epilepsy treatment, over 20 anti-seizure medications (ASMs) have gained approval from Drug Regulatory Agencies, each delineating clear indications. However, the complexity of managing drug-resistant epilepsy often necessitates the concurrent use of multiple medications. This therapeutic challenge highlights a notable gap: the absence of standardized guidelines, compelling clinicians to rely on empirical clinical experience when selecting combination therapies. This comprehensive review aims to explore current evidence elucidating the preferential utilization of specific ASMs or their combinations, with a primary emphasis on pharmacodynamic considerations. The fundamental objective underlying rational polytherapy is the strategic combination of medications, harnessing diverse mechanisms of action to optimize efficacy while mitigating shared side effects. Moreover, the intricate interplay between epilepsy and comorbidities partly may influence the treatment selection process. Despite advancements, unresolved queries persist, notably concerning the mechanisms underpinning drug resistance and the paradoxical exacerbation of seizures. By synthesizing existing evidence and addressing pertinent unresolved issues, this review aims to contribute to the evolving landscape of paediatric epilepsy treatment strategies, paving the way for more informed and efficacious therapeutic interventions.

The effect of executive function on health related quality of life in children with self-limited epilepsy with centrotemporal spikes

AIM

The current study aims to investigate the effect of Executive Functions (EFs) on Health Related Quality of Life (HRQoL) in a cohort of children with self-limited epilepsy with centrotemporal spikes (SeLECTS) and to identify possible factors that impact HRQoL specifically related to epilepsy-related variables and EFs skills.

MATERIAL AND METHOD

The Pediatric Quality of Life Inventory 4.0 Generic Core Scales (PedsQL) and The Behavior Rating Inventory of Executive Function (BRIEF-2 and BRIEF-P) were completed by the parents of 129 patients with SeLECTS. Demographic variables and epilepsy-related variables were collected.

RESULTS

Our sample performed in the average range across all the subscales and summary scores of the PedsQL and performed in the normal range of the BRIEF questionnaire. We observed that a lower functioning in EFs was associated with lower overall HRQoL scores. We explored the relationship between epilepsy characteristics and scores on the PedsQL. We found that the use of antiseizure medications (ASMs), longer duration of the treatment, and a higher seizure frequency were associated with a lower HRQoL. Moreover, we observed that executive dysfunction was a significant predictor of reduced HRQoL.

CONCLUSION

Our results suggest the importance of the identification of patients with SeLECTS with a high level of risk for a poor HRQoL. We may now add executive dysfunction to the list of known risk factors for poor HRQoL in children with SeLECTS, along with such factors as seizure frequency, recent seizures, use of ASMs and longer duration of therapy. The early identification of children with SeLECTS at risk of a poor HRQoL could allow the activation of adequate interventions.

Zonisamide: A Comprehensive, Updated Review for the Clinician

Purpose of Review

Zonisamide (ZNS) was first approved in the United States in 2000 for the adjunctive treatment of patients aged 16 years or older with partial (focal) seizures. Although ZNS has been proven to treat multiple seizure types, it has been largely underutilized in US clinical practice.

Recent Findings

Published literature demonstrated that antiseizure medications (ASMs) acting on Na+ and Ca2+ channels may add beneficial effects in many seizure types by reducing seizure frequency and leading to overall improvements. In addition, effects of ZNS may lead to clinical improvements in Parkinson disease, alcohol and sleep disorders, pain, and migraine. ZNS is available in multiple formulations and is a safe and effective, broad spectrum ASM.

Summary

The purpose of this review was to provide an update to what is known about the efficacy of ZNS and where it shows benefits in the treatment of patients with epilepsy and other CNS disorders through its many unique mechanisms of action.

Epilepsy in childhood and school performance: a nation-wide cohort study

Childhood epilepsy has been linked to poor academic performance, but large-scale studies are lacking. In this nation-wide study of school-aged children, we examined the association between childhood epilepsy and school performance in standardized tests according to phenotypic and treatment-related characteristics. We performed a matched register-based cohort study of children born in Denmark (1997-2009) who participated in the Danish National School Test Programme between 2010 and 2019. We used population and health registers to identify children with epilepsy and a randomly sampled sex- and age-matched reference cohort without epilepsy (ratio 1:10). Norm-based test scores from language and mathematics reflecting performance as a percentile of the nation-wide distribution of scores (scale 1-100) were used to assess academic performance. Adjusted differences in mean standardized scores between children with and without epilepsy were estimated using linear regression models. Among 582 840 children participating in the School Test Programme, we identified 4659 (0.8%) children with epilepsy (52.8% males) and 46 590 matched reference children. Median age at epilepsy onset was 7.5 years (interquartile range: 4.0-10.6). Childhood epilepsy was associated with poorer school performance overall (mean score = 48.2 versus references = 56.7; adjusted difference = -6.7, 95% CI: -7.4 to -6.0), and worse performance was found in all epilepsy subgroups, including in 3534 children with uncomplicated epilepsy (i.e. no other pre-existing neurologic or intellectual disabilities and no identified possible cause for epilepsy; adjusted difference = -6.0, 95% CI: -6.8 to -5.2). No major variation by sex, age or subject was observed, but larger score differences were seen in children using antiseizure medication at time of testing (e.g. valproate monotherapy, adjusted difference = -9.3, 95% CI: -11.5 to -7.0 and lamotrigine monotherapy, adjusted difference = -13.1, 95% CI: -15.0 to -11.3) and in children with psychiatric comorbidity, especially epilepsy with comorbid intellectual disability (adjusted difference = -27.0, 95% CI: -30.0 to -23.9) and epilepsy with comorbid attention deficit/hyperactivity disorder (adjusted difference = -15.7, 95% CI: -19.0 to -12.4). Children with epilepsy scored significantly lower than their unaffected siblings (adjusted difference = -6.2, 95% CI: -7.1 to -5.4). In conclusion, childhood epilepsy was associated with impaired academic performance throughout schooling, which suggest that there is a widespread need for educational support of children with epilepsy, even when the child has no other comorbidities and when the epilepsy appears well-managed.

Valproate use associated with frontal and cerebellar gray matter volume reductions: A voxel-based morphometry study

Recent morphometric magnetic resonance imaging (MRI) studies suggested the possibility that valproate (VPA) use is associated with parieto-occipital cortical thinning in patients with heterogeneous epilepsy syndromes. In this study, we examined the effect of VPA on the brain volume using a large number of homogenous patients with idiopathic generalized epilepsy. Voxel-based morphometry was used to compare regional gray matter (GM) volume between 112 patients currently taking VPA (VPA+ group), 81 patients not currently taking VPA (VPA- group), and 120 healthy subjects (control group). The VPA+ group showed a significant GM volume reduction in the bilateral cerebellum, hippocampus, insula, caudate nucleus, medial frontal cortex/anterior cingulate cortex, primary motor/premotor cortex, medial occipital cortex, and anteromedial thalamus, as compared to the control group. The VPA- group showed a significant GM volume reduction in the anteromedial thalamus and right hippocampus/temporal cortex, as compared to the control group. Compared to the VPA- group, the VPA+ group had a significant GM volume reduction in the bilateral cerebellum, primary motor/premotor cortex, and medial frontal cortex/anterior cingulate cortex. We have provided evidence that VPA use could result in GM volume reductions in the frontal cortex and cerebellum. Our findings should be acknowledged as a potential confounding factor in morphometric MRI studies that include subjects taking VPA.

IQ changes after pediatric epilepsy surgery: a systematic review and meta-analysis

OBJECTIVE

This systematic review aimed to assess the intellectual outcome of children who underwent surgery for epilepsy.

METHODS

A systematic review of electronic databases was conducted on December 3, 2021, for PubMed and January 11, 2022, for Web of Science. The review was conducted according to the PRISMA guidelines. The included studies reported on intelligence quotient (IQ) or developmental quotient (DQ) before and after epilepsy surgery in children. Studies were included, if the patients had medically intractable epilepsy and if the study reported mainly on curative surgical procedures. We conducted a random-effects meta-analysis to determine the mean change of IQ/DQ.

RESULTS

Fifty-seven studies reporting on a total of 2593 patients met the inclusion criteria. The mean age at surgery was 9.2 years (± 3.44; range 2.4 months-19.81 years). Thirty-eight studies showed IQ/DQ improvement on a group level, 8 yielded stable IQ/DQ, and 19 showed deterioration. Pooled analysis revealed a significant mean gain in FSIQ of + 2.52 FSIQ points (95% CI 1.12-3.91). The pooled mean difference in DQ was + 1.47 (95% CI - 6.5 to 9.5). The pooled mean difference in IQ/DQ was 0.73 (95% CI - 4.8 to 6.2). Mean FSIQ gain was significantly higher in patients who reached seizure freedom (+ 5.58 ± 8.27) than in patients who did not (+ 0.23 ± 5.65). It was also significantly higher in patients who stopped ASM after surgery (+ 6.37 ± 3.80) than in patients who did not (+ 2.01 ± 2.41). Controlled studies showed a better outcome in the surgery group compared to the non-surgery group. There was no correlation between FSIQ change and age at surgery, epilepsy duration to surgery, and preoperative FSIQ.

SIGNIFICANCE

The present review indicates that there is a mean gain in FSIQ and DQ in children with medically intractable epilepsy after surgery. The mean gain of 2.52 FSIQ points reflects more likely sustainability of intellectual function rather than improvement after surgery. Seizure-free and ASM-free patients reach higher FSIQ gains. More research is needed to evaluate individual changes after specific surgery types and their effect on long-term follow-up.

Cognitive effect of antiseizure medications in medial temporal lobe epilepsy

BACKGROUND AND PURPOSE

The specific effects of antiseizure medications (ASMs) on cognition are a rich field of study, with many ongoing questions. The aim of this study was to evaluate these effects in a homogeneous group of patients with epilepsy to guide clinicians to choose the most appropriate medications.

METHODS

We retrospectively identified 287 refractory patients with medial temporal lobe epilepsy associated with hippocampal sclerosis. Scores measuring general cognition (global, verbal and performance IQ), working memory, episodic memory, executive functions, and language abilities were correlated with ASM type, number, dosage and generation (old vs. new). We also assessed non-modifiable factors affecting cognition, such as demographics and epilepsy-related factors.

RESULTS

Key parameters were total number of ASMs and specific medications, especially topiramate (TPM) and sodium valproate (VPA). Four cognitive profiles of the ASMs were identified: (i) drugs with an overall detrimental effect on cognition (TPM, VPA); (ii) drugs with negative effects on specific areas: verbal memory and language skills (carbamazepine), and language functions (zonisamide); (iii) drugs affecting a single function in a specific and limited area: visual denomination (oxcarbazepine, lacosamide); and (iv) drugs without documented cognitive side effects. Non-modifiable factors such as age at testing, age at seizure onset, and history of febrile seizures also influenced cognition and were notably influenced by total number of ASMs.

CONCLUSION

We conclude that ASMs significantly impact cognition. Key parameters were total number of ASMs and specific medications, especially TPM and VPA. These results should lead to a reduction in the number of drugs received and the avoidance of medications with unfavorable cognitive profiles.

How the Spreading and Intensity of Interictal Epileptic Activity Are Associated with Visuo-Spatial Skills in Children with Self-Limited Focal Epilepsy with Centro-Temporal Spikes

This paper investigates brain-behaviour associations between interictal epileptic discharges and cognitive performance in a population of children with self-limited focal epilepsy with centro-temporal spikes (SeLECTS). Sixteen patients with SeLECTS underwent an extensive neuropsychological assessment, including verbal short-term and episodic memory, non-verbal short-term memory, attentional abilities and executive function. Two quantitative EEG indices were analysed, i.e., the Spike Wave Index (SWI) and the Spike Wave Frequency (SWF), and one qualitative EEG index, i.e., the EEG score, was used to evaluate the spreading of focal SW to other parts of the brain. We investigated associations between EEG indices and neuropsychological performance with non-parametric Spearman correlation analyses, including correction for multiple comparisons. The results showed a significant negative correlation between (i) the awake EEG score and the Block Tapping Test, a visuo-spatial short-term memory task, and (ii) the sleep SWI and the Tower of London, a visuo-spatial planning task (pcorr < 0.05). These findings suggest that, in addition to the usual quantitative EEG indices, the EEG analysis should include the qualitative EEG score evaluating the spreading of focal SW to other parts of the brain and that neuropsychological assessment should include visuo-spatial skills.

Long-term safety and efficacy of adjunctive brivaracetam in pediatric patients with epilepsy: An open-label, follow-up trial

OBJECTIVE

This study was undertaken to evaluate the long-term safety, tolerability, and efficacy of adjunctive brivaracetam (BRV) treatment in pediatric patients with epilepsy.

METHODS

A phase 3, open-label, multicenter, long-term follow-up trial (N01266; NCT01364597) was conducted on patients (aged 1 month to <17 years at core trial entry; direct enrollers aged 4 to <17 years) treated with BRV. Outcomes included treatment-emergent adverse events (TEAEs), behavior assessments (Achenbach Child Behavior Checklist [CBCL], Behavior Rating Inventory of Executive Function [BRIEF]/BRIEF-Preschool version [BRIEF-P]), and efficacy outcomes (percent change in focal seizure frequency, 50% responder rate for all seizure types for patient subgroups <2 years and ≥2 years of age using daily record card data).

RESULTS

Of 257 patients with ≥1 dose of BRV (141 [54.9%] male; mean age = 8.0 years [SD = 4.5]), 36 patients were <2 years of age, and 72.0% of patients had a history of focal seizures. Mean BRV exposure was 3.2 patient-years. At least one TEAE occurred in 93.4% patients, and 32.3% had serious TEAEs. Seven patients died during the trial; no deaths were considered treatment-related. Patients ≥2 years of age had a median decrease in 28-day adjusted focal seizure frequency of 62.9%, and 50.9% had a ≥50% response in all seizures. Patients <2 years of age had a median decrease in 28-day adjusted focal seizure frequency of 96.9%, and 68.2% had a ≥50% response in all seizures. Kaplan-Meier estimated treatment retention was 72.7%, 64.5%, 57.8%, 53.3%, 50.1%, and 44.8% at 1, 2, 3, 4, 5, and 6 years, respectively. Mean changes (baseline to last evaluation) for all Achenbach CBCL and BRIEF-P/BRIEF subscale scores were negative, reflecting stability/slight improvement.

SIGNIFICANCE

Long-term adjunctive BRV treatment was generally well tolerated and efficacious in reducing seizure frequency, and had high retention rates, with generally stable cognitive/behavioral scores in pediatric patients with epilepsy.

Antiseizure Medications in Alzheimer's Disease from Preclinical to Clinical Evidence

Alzheimer's disease (AD) and epilepsy are common neurological disorders in the elderly. A bi-directional link between these neurological diseases has been reported, with patients with either condition carrying almost a two-fold risk of contracting the other compared to healthy subjects. AD/epilepsy adversely affects patients' quality of life and represents a severe public health problem. Thus, identifying the relationship between epilepsy and AD represents an ongoing challenge and continuing need. Seizures in AD patients are often unrecognized because they are often nonconvulsive and sometimes mimic some behavioral symptoms of AD. Regarding this, it has been hypothesized that epileptogenesis and neurodegeneration share common underlying mechanisms. Targeted treatment to decrease epileptiform activity could represent a valuable strategy for delaying the neurodegenerative process and related cognitive impairment. Several preclinical studies have shown that some antiseizure medications (ASMs) targeting abnormal network hyperexcitability may change the natural progression of AD. However, to date, no guidelines are available for managing seizures in AD patients because of the paucity of randomized clinical trials sufficient for answering the correlated questions. Future AD clinical studies are mandatory to update clinicians about the symptomatic treatment of seizures in AD patients and recognize whether ASM therapy could change the natural progression of the disease, thereby rescuing cognitive performance.

The broad-spectrum activity of perampanel: state of the art and future perspective of AMPA antagonism beyond epilepsy

Glutamate is the brain's main excitatory neurotransmitter. Glutamatergic neurons primarily compose basic neuronal networks, especially in the cortex. An imbalance of excitatory and inhibitory activities may result in epilepsy or other neurological and psychiatric conditions. Among glutamate receptors, AMPA receptors are the predominant mediator of glutamate-induced excitatory neurotransmission and dictate synaptic efficiency and plasticity by their numbers and/or properties. Therefore, they appear to be a major drug target for modulating several brain functions. Perampanel (PER) is a highly selective, noncompetitive AMPA antagonist approved in several countries worldwide for treating different types of seizures in various epileptic conditions. However, recent data show that PER can potentially address many other conditions within epilepsy and beyond. From this perspective, this review aims to examine the new preclinical and clinical studies-especially those produced from 2017 onwards-on AMPA antagonism and PER in conditions such as mesial temporal lobe epilepsy, idiopathic and genetic generalized epilepsy, brain tumor-related epilepsy, status epilepticus, rare epileptic syndromes, stroke, sleep, epilepsy-related migraine, cognitive impairment, autism, dementia, and other neurodegenerative diseases, as well as provide suggestions on future research agenda aimed at probing the possibility of treating these conditions with PER and/or other AMPA receptor antagonists.

What are the considerations when initiating treatment for epilepsy in children?

INTRODUCTION

There is a very wide spectrum of epilepsies and developmental and epileptic encephalopathies that affect children, from self-limited forms, not necessarily requiring treatment, to severe drug-resistant ones.

AREAS COVERED

In this perspective, the authors discuss the main factors to consider before drug prescription in children, considering the most recent clinical research, including age, seizure type, epilepsy syndrome, etiology, efficacy and safety profile, comorbidities, gender, available formulations, costs and drug coverage, and regulatory issues. The literature search was conducted through a PubMed search on antiseizure medications for patients aged 0-18, with respect to each of the aforementioned factors, and by checking the reference lists of relevant papers.

EXPERT OPINION

The most expanding field of research and innovation for clinical practice is precision medicine, which addresses the holistic treatment of genetic epilepsies and developmental and epileptic encephalopathies. It achieves this by addressing their detrimental effects on synapses, neurotransmission, and cellular signaling pathways with the double aim to treat seizures and to rescue neurodevelopmental trajectories, but also the issue of adverse events and drug resistance through pharmacogenomics.

How have the recent updated epilepsy classifications impacted on diagnosis and treatment?

INTRODUCTION

Epilepsies are a diverse group of disorders which differ regarding prognosis for seizure control and associated comorbidities. Accurate classification is critical to choose the highest yield investigations and best therapeutic options and to provide the most accurate prognoses regarding the expected degree of seizure control, possible remission, and risk of associated comorbidities to patients and their families. This article reviews the recent updates in epilepsy classification to illustrate how accurate classification impacts care for persons with epilepsy.

AREAS COVERED

The authors discuss the ILAE 2017 Classification of the Epilepsies along with the modification of the classification for neonatal seizures and epilepsies. They also discuss the ILAE position papers on Epilepsy syndromes in neonates and infants and children of variable age and the Idiopathic Generalized Epilepsies.

EXPERT OPINION

Accurate epilepsy classification allows selection of the highest yield investigations, choice of optimal therapies, and accurate prognostication of seizures (likelihood of response to antiseizure treatments and likelihood of remission with age), as well as comorbidities (likelihood, type, and severity). As we move into the era of disease modifying therapy, early accurate identification of underlying causes with timely introduction of specific treatments will be crucial to lessen the severity of epilepsy, with improved seizure control and attenuation of associated comorbidities.

Mining and analysis of adverse drug reactions associated with perampanel based on FAERS database

INTRODUCTION

Perampanel (PER) is a non-competitive AMPA glutamate receptor antagonist used as an anti-seizure medication. Large post-marketing databases are still lacking for safety analysis of the new generation of anti-seizure medications. Based on the FDA's adverse event reporting system (FAERS) database, this study aimed to investigate, assess, and offer evidence for the safety of PER to support clinical decision-making.

METHODS

Perampanel-related adverse reaction signals were mined using the reporting odds ratio (ROR), medicines and healthcare products regulatory agency (MHRA), and Bayesian confidence propagation neural network (BCPNN). The rate and occurrence of reported adverse responses were examined.

RESULTS

With the three methodologies used in combination, 83 signals mostly related to psychosis and different nervous system disorders were detected. Among them, suicide behavior, respiratory depression, hepatotoxicity, cognitive impairment, and other possible novel signals warranted consideration. Further examination of the age and gender differences in the detected signals revealed that elderly patients should be closely monitored for any change in consciousness and the occurrence of movement disorders; male patients should be observed for negative mental reactions like a personal attack and homicidal ideation; and female patients should be watched for the occurrence of negative reactions in memory, weight, vision, liver function, and other specific areas.

CONCLUSIONS

This study found that PER had the risk of causing suicide behavior, respiratory depression, hepatotoxicity, and cognitive impairment among other adverse effects. When used clinically, PER should be closely monitored for the occurrence of adverse effects on mental health and behavior. However, these results should be interpreted with caution.

A narrative review of the mechanisms and consequences of intermittent hypoxia and the role of advanced analytic techniques in pediatric autonomic disorders

Disorders of autonomic functions are typically characterized by disturbances in multiple organ systems. These disturbances are often comorbidities of common and rare diseases, such as epilepsy, sleep apnea, Rett syndrome, congenital heart disease or mitochondrial diseases. Characteristic of many autonomic disorders is the association with intermittent hypoxia and oxidative stress, which can cause or exaggerate a variety of other autonomic dysfunctions, making the treatment and management of these syndromes very complex. In this review we discuss the cellular mechanisms by which intermittent hypoxia can trigger a cascade of molecular, cellular and network events that result in the dysregulation of multiple organ systems. We also describe the importance of computational approaches, artificial intelligence and the analysis of big data to better characterize and recognize the interconnectedness of the various autonomic and non-autonomic symptoms. These techniques can lead to a better understanding of the progression of autonomic disorders, ultimately resulting in better care and management.

Lesion Extent Negatively Impacts Intellectual Skills in Pediatric Focal Epilepsy

BACKGROUND

Cognitive development in children and adolescents with focal lesional epilepsy is determined by the underlying epileptogenic lesion, in addition to epilepsy itself. However, the impact of lesion-related variables on intelligence quotient (IQ) and developmental quotient (DQ) remains largely unexplored. Here, we aimed to determine the effect of lesion-related predictors and their relation with epilepsy-related predictors of intellectual functioning.

METHODS

We retrospectively analyzed data from children with focal lesional epilepsy who underwent standardized cognitive evaluation yielding IQ/DQ in our institution.

RESULTS

We included 50 consecutive patients aged 0.5 to 17.5 years (mean, 9.3; S.D., 4.9) at cognitive assessment. Epilepsy duration was 0 to 15.5 years (mean, 3.8; S.D., 4.1). Of the total cohort, 30 (60%) patients had unilobar lesions, seven (14%) multilobar, 10 (20%) hemispheric, and three (6%) bilateral. Etiology was congenital in 32 (64%) cases, acquired in 14 (28%), and progressive in four (8%). For patients with unilobar lesions, the mean IQ/DQ was 97.1 ± 15.7, for multilobar 98.9 ± 20.2, for hemispheric 76.1 ± 20.5, and for bilateral 76.3 ± 4.5. Larger lesion extent, earlier epilepsy onset, and longer epilepsy duration correlated with lower IQ/DQ in the univariate analysis, whereas only lesion extent and epilepsy duration contributed significantly to the explanatory model in the multivariable analysis.

CONCLUSIONS

The present study demonstrates that lesion extent and epilepsy duration are important risk factors for intellectual impairment in pediatric patients with focal lesional epilepsy. These findings are useful for family counseling and the early consideration of interventions that may limit the duration of epilepsy.

Newer Antiseizure Medications and Suicidality: Analysis of the Food and Drug Administration Adverse Event Reporting System (FAERS) Database

BACKGROUND

The association between antiseizure medications (ASMs) and suicidality remains controversial. Analyses of additional datasets are needed to further elucidate the complex relationship between antiseizure medications and suicidality.

OBJECTIVE

The aim of this study was to compare the safety profile of newer ASMs with older ASMs through an analysis of the US Food and Drug Administration Adverse Event Reporting System (FAERS) database, with a focus on suicidality.

METHODS

We queried over 17 million reports in the FAERS database from 2012 to 2021 and identified cases involving ASMs. After removing incomplete and duplicate reports, the study cohort consisted of lacosamide (n = 7593), perampanel (n = 1813), clobazam (n = 3827), brivaracetam (n = 1166), and vigabatrin (n = 5293) compared with a control group of older ASMs (topiramate, lamotrigine, valproic acid, carbamazepine, levetiracetam; n = 71,535). Cases of suicidality (completed suicide, suicidal ideation, attempted suicide, suicidal behavior, suicidal depression) were identified in each group. Adjusted (age and sex) odds ratios (aOR) and associated 95% confidence intervals (CI) were calculated using logistic regression analysis for each new drug when compared with the control group of older ASM drugs.

RESULTS

A total of 6309 cases of suicidality were identified among reports with ASMs. Most reports were sourced from healthcare professionals (5516, 87.4%). The proportion of reports involving suicidality were 210/7593 (2.8%) for lacosamide, 185/1813 (10.2%) for perampanel, 108/3827 (2.8%) for clobazam, 57/1166 (4.9%) for brivaracetam, 14/5293 (0.3%) for vigabatrin, and 5735/71,535 (8.0%) for older ASMs. Compared with older ASMs, the aOR for suicidality was 0.33 (95% CI 0.28-0.38) for lacosamide, 1.34 (95% CI 1.15-1.56) for perampanel, 0.35 (95% CI 0.29-0.43) for clobazam, 0.60 (95% CI 0.45-0.77) for brivaracetam, and 0.03 (95% CI 0.02-0.05) for vigabatrin.

CONCLUSION

When compared with older ASMs, four newer ASMs (lacosamide, clobazam, brivaracetam, and vigabatrin) were found to have significantly lower odds of suicidality, while perampanel was found to significantly increase the odds of suicidality. Pronounced variability (greater than 30 fold) in the proportion of FAERS reports associated with suicidality among the drugs studied was identified. The results of this case control study of FDA adverse event reports spanning 10 years and 6309 cases of suicidality expand our understanding of the safety profile of newer ASMs.

Fenfluramine: a plethora of mechanisms?

Developmental and epileptic encephalopathies are rare, treatment-resistant epilepsies with high seizure burden and non-seizure comorbidities. The antiseizure medication (ASM) fenfluramine is an effective treatment for reducing seizure frequency, ameliorating comorbidities, and potentially reducing risk of sudden unexpected death in epilepsy (SUDEP) in patients with Dravet syndrome and Lennox-Gastaut syndrome, among other rare epilepsies. Fenfluramine has a unique mechanism of action (MOA) among ASMs. Its primary MOA is currently described as dual-action sigma-1 receptor and serotonergic activity; however, other mechanisms may be involved. Here, we conduct an extensive review of the literature to identify all previously described mechanisms for fenfluramine. We also consider how these mechanisms may play a role in the reports of clinical benefit in non-seizure outcomes, including SUDEP and everyday executive function. Our review highlights the importance of serotonin and sigma-1 receptor mechanisms in maintaining a balance between excitatory (glutamatergic) and inhibitory (γ-aminobutyric acid [GABA]-ergic) neural networks, and suggests that these mechanisms may represent primary pharmacological MOAs in seizures, non-seizure comorbidities, and SUDEP. We also describe ancillary roles for GABA neurotransmission, noradrenergic neurotransmission, and the endocrine system (especially such progesterone derivatives as neuroactive steroids). Dopaminergic activity underlies appetite reduction, a common side effect with fenfluramine treatment, but any involvement in seizure reduction remains speculative. Further research is underway to evaluate promising new biological pathways for fenfluramine. A better understanding of the pharmacological mechanisms for fenfluramine in reducing seizure burden and non-seizure comorbidities may allow for rational drug design and/or improved clinical decision-making when prescribing multi-ASM regimens.

Evaluation of functional mobility, balance, and executive functions in children with epilepsy

OBJECTIVE

It is known that motor skills and executive functions are interrelated in healthy children. The study aims to evaluate the functional mobility, balance and executive functions in children who are diagnosed with epilepsy and to determine whether they are related to each other.

METHODS

The study included 21 children who were diagnosed with epilepsy and have no additional comorbidities and 21 healthy children who had similar age and sex to those diagnosed with epilepsy. Their demographic data were collected using a descriptive information form. In addition, the Timed Up and Go Test (TUG) and the Stair Climb Test (SCT) were used to evaluate their functional mobility, the Pediatric Berg Balance Scale (PBSS) to evaluate their balance, and the Behavior Evaluation Inventory for Executive Functions Parent Form (BRIEF-P) to evaluate their executive functions.

RESULTS

Our study found a statistically significant difference between the children with epilepsy and their healthy peers in terms of functional mobility and executive functions (p < 0.05). However, there was no statistically significant difference between them in terms of balance parameters (p > 0.05). In addition, a statistically significant difference was found between the executive functions and functional mobility in children with epilepsy (p < 0.05). The coefficient of determinations (R2) indicating how differences in T and SCT scores explained by executive function domains were found as 0.718 and 0.725, respectively.

CONCLUSIONS

Epilepsy can negatively affect several aspects of functional mobility and executive functions in childhood. According to the results of our study, it is important to recognize the motor skills and executive functions problems of children with epilepsy who do not have additional comorbidities, and to direct them to appropriate healthcare programs. Our results support the need to raise awareness in both health professionals and families to encourage children with epilepsy to be more active.

Is There a Cognitive Decline in Pediatric Patients Following Epilepsy Surgery?

BACKGROUND

Epilepsy surgery is currently the only way to cure drug-resistant epilepsy (DRE). The loss of epileptic activity or its propagation in the developing brain may not only result in seizure freedom but also be associated with further positive effects. Here, we analyzed the cognitive development of children and adolescents with DRE after epilepsy surgery.

METHODS

We evaluated retrospectively the cognitive development of children and adolescents before and after epilepsy surgery.

RESULTS

Fifty-three children and adolescents underwent epilepsy surgery at a median age of 7.62 years. Overall seizure freedom was 86.8% at a current median observation period of 20 months. Presurgically, 81.1% had the clinical diagnosis of cognitive impairment, which was confirmed by standardized tests in 43 of 53 patients (76.7%). Further 10 patients had severe cognitive impairment rendering a standardized test impossible. The median intelligence quotient (IQ)/development quotient value was 74. After surgery, caretakers reported developmental progress in all patients, whereas the median IQ decreased slightly (P = 0.404). In eight patients the IQ points decreased after surgery; however, their individual raw scores increased in line with their reported increase in cognitive abilities.

CONCLUSIONS

We did not detect any cognitive deterioration in children following epilepsy surgery. A loss of IQ points did not correspond to a real loss of cognitive abilities. These patients developed more slowly than age-matched peers with an average development speed but profited individually as seen in their raw scores. Therefore, an individual analysis of raw scores is relevant to assess the cognitive development after surgery.

Fenfluramine treatment is associated with improvement in everyday executive function in preschool-aged children (<5 years) with Dravet syndrome: A critical period for early neurodevelopment

OBJECTIVE

To evaluate whether fenfluramine (FFA) is associated with improvement in everyday executive function (EF)-self-regulation-in preschool-aged children with Dravet syndrome (DS).

METHODS

Children with DS received placebo or FFA in one of two phase III studies (first study: placebo, FFA 0.2 mg/kg/day, or FFA 0.7 mg/kg/day added to stiripentol-free standard-of-care regimens; second study: placebo or FFA 0.4 mg/kg/day added to stiripentol-inclusive regimens). Everyday EF was evaluated at baseline and Week 14-15 for children aged 2-4 years with parent ratings on the Behavior Rating Inventory of Executive Function®-Preschool (BRIEF®-P); raw scores were transformed to T-scores and summarized in Inhibitory Self-Control Index (ISCI), Flexibility Index (FI), Emergent Metacognition Index (EMI), and Global Executive Composite (GEC). Clinically meaningful improvement and worsening were defined using RCI ≥ 90% and RCI ≥ 80% certainty, respectively. The associations between placebo vs FFA combined (0.2, 0.4, and 0.7 mg/kg/day) or individual treatment groups and the likelihood of clinically meaningful change in BRIEF®-P indexes/composite T-scores were evaluated using Somers'd; pairwise comparisons were calculated by 2-sided Fisher's Exact tests (p ≤ 0.05) and Cramér's V.

RESULTS

Data were analyzed for 61 evaluable children of median age 3 years (placebo, n = 22; FFA 0.2 mg/kg/day, n = 15; 0.4 mg/kg/day [with stiripentol], n = 10; 0.7 mg/kg/day, n = 14 [total FFA, n = 39]). Elevated or problematic T-scores (T ≥ 65) were reported in 55% to 86% of patients at baseline for ISCI, EMI, and GEC, and in ∼33% for FI. Seventeen of the 61 children (28%) showed reliable, clinically meaningful improvement (RCI ≥ 90% certainty) in at least one BRIEF®-P index/composite, including a majority of the children in the FFA 0.7 mg/kg/day group (9/14, 64%). Only 53% of these children (9/17) also experienced clinically meaningful reduction (≥50%) in monthly convulsive seizure frequency, including 6/14 patients in the FFA 0.7 mg/kg/day group. Overall, there were positive associations between the four individual treatment groups and the likelihood of reliable, clinically meaningful improvement in all BRIEF®-P indexes/composite (ISCI, p = 0.001; FI, p = 0.005; EMI, p = 0.040; GEC, p = 0.002). The FFA 0.7 mg/kg/day group showed a greater likelihood of reliable, clinically meaningful improvement than placebo in ISCI (50% vs 5%; p = 0.003), FI (36% vs 0%; p = 0.005), and GEC (36% vs 0%; p = 0.005). For EMI, the FFA 0.7 mg/kg/day group showed a greater likelihood of reliable, clinically meaningful improvement than the FFA 0.2 mg/kg/day group (29% vs 0%; p = 0.040), but did not meet the significance threshold compared with placebo (29% vs 5%; p = 0.064). There were no significant associations between treatment and the likelihood of reliable, clinically meaningful worsening (p > 0.05).

SIGNIFICANCE

In this preschool-aged DS population with high baseline everyday EF impairment, FFA treatment for 14-15 weeks was associated with dose-dependent, clinically meaningful improvements in regulating behavior, emotion, cognition, and overall everyday EF. These clinically meaningful improvements in everyday EF were not entirely due to seizure frequency reduction, suggesting that FFA may have direct effects on everyday EF during the early formative years of neurodevelopment.

Fenfluramine provides clinically meaningful reduction in frequency of drop seizures in patients with Lennox-Gastaut syndrome: Interim analysis of an open-label extension study

OBJECTIVE

This study was undertaken to evaluate the long-term safety and effectiveness of fenfluramine in patients with Lennox-Gastaut syndrome (LGS).

METHODS

Eligible patients with LGS who completed a 14-week phase 3 randomized clinical trial enrolled in an open-label extension (OLE; NCT03355209). All patients were initially started on .2 mg/kg/day fenfluramine and after 1 month were titrated by effectiveness and tolerability, which were assessed at 3-month intervals. The protocol-specified treatment duration was 12 months, but COVID-19-related delays resulted in 142 patients completing their final visit after 12 months.

RESULTS

As of October 19, 2020, 247 patients were enrolled in the OLE. Mean age was 14.3 ± 7.6 years (79 [32%] adults) and median fenfluramine treatment duration was 364 days; 88.3% of patients received 2-4 concomitant antiseizure medications. Median percentage change in monthly drop seizure frequency was -28.6% over the entire OLE (n = 241) and -50.5% at Month 15 (n = 142, p < .0001); 75 of 241 patients (31.1%) experienced ≥50% reduction in drop seizure frequency. Median percentage change in nondrop seizure frequency was -45.9% (n = 192, p = .0038). Generalized tonic-clonic seizures (GTCS) and tonic seizures were most responsive to treatment, with median reductions over the entire OLE of 48.8% (p < .0001, n = 106) and 35.8% (p < .0001, n = 186), respectively. A total of 37.6% (95% confidence interval [CI] = 31.4%-44.1%, n = 237) of investigators and 35.2% of caregivers (95% CI = 29.1%-41.8%, n = 230) rated patients as Much Improved/Very Much Improved on the Clinical Global Impression of Improvement scale. The most frequent treatment-emergent adverse events were decreased appetite (16.2%) and fatigue (13.4%). No cases of valvular heart disease (VHD) or pulmonary arterial hypertension (PAH) were observed.

SIGNIFICANCE

Patients with LGS experienced sustained reductions in drop seizure frequency on fenfluramine treatment, with a particularly robust reduction in frequency of GTCS, the key risk factor for sudden unexpected death in epilepsy. Fenfluramine was generally well tolerated; VHD or PAH was not observed long-term. Fenfluramine may provide an important long-term treatment option for LGS.

Optimization of Therapy in Patients with Epilepsy and Psychiatric Comorbidities: Key Points

Psychiatric disorder comorbidity in patients with epilepsy (PWE) is very frequent with a mean percentage prevalence of up to 50% and even higher. Such a high frequency suggests that epilepsy and psychiatric disorders might share common pathological pathways. Various aspects contribute in making the matter very complex from a therapeutic point of view. Some antiseizure medications (ASMs), namely valproic acid, carbamazepine, and lamotrigine, have mood-stabilising effects and are routinely used for the treatment of bipolar disorder in patients who do not have epilepsy. Pregabalin and, to a lesser extent, gabapentin, exerts anxiolytic effects. However, several ASMs, in particular levetiracetam, topiramate, and perampanel, may contribute to psychiatric disorders, including depression, aggressive behaviour, and even psychosis. If these ASMs are prescribed, the patient should be monitored closely. A careful selection should be made also with psychotropic drugs. Although most of these can be safely used at therapeutic doses, bupropion, some tricyclic antidepressants, maprotiline, and clozapine may alter seizure threshold and facilitate epileptic seizures. Interactions between ASMs and psychotropic medication may make it difficult to predict individual response. Pharmacokinetic interactions can be assessed with drug monitoring and are consequently much better documented than pharmacodynamic interactions. Another aspect that needs a careful evaluation is patient adherence to treatment. Prevalence of non-adherence in PWE and psychiatric comorbidities is reported to reach values even higher than 70%. A careful evaluation of all these aspects contributes in optimizing therapy with a positive impact on seizure control, psychiatric wellbeing, and quality of life.

Effect of Oxcarbazepine on Language Function in Patients With Newly Diagnosed Pediatric Epilepsy

BACKGROUND AND PURPOSE

This study aimed to determine the effects of oxcarbazepine (OXC) on the language function of patients with pediatric epilepsy.

METHODS

We assessed the language abilities of patients aged 5-17 years with newly diagnosed focal epilepsy and the same number of age-matched healthy children using the Test of Problem Solving (TOPS) and the Receptive and Expressive Vocabulary Test-Receptive (REVT-R). The Mean Length of Utterance-words (MLU-w) was used to estimate linguistic productivity before and after OXC initiation. All patients received OXC monotherapy with a starting dosage of 10 mg/kg/day for 1 week, which in some cases was increased to 30 mg/kg/day (or 1,200 mg/day).

RESULTS

The study finally included 41 pediatric patients (22 males and 19 females; age 9.9±3.0 years, mean±standard deviation). All language parameters of the TOPS improved significantly after initiating OXC (determining cause, 12.5±4.8-13.7±4.1 [p=0.016]; making inference, 15.6±5.6-17.4±6.4 [p<0.001]; and predicting, 9.8±5.0-11.6±4.5 [p=0.001]). However, patients who received OXC did not exhibit a significantly extended MLU-w (determining cause, p=0.493; making inference, p=0.386; and predicting, p=0.341). Receptive language scores also significantly increased after taking OXC (REVT-R: 121.0±43.1-129.4±43.8, p=0.002), but the percentage of development age to chronological age did not vary (REVT-developmental quotient: p=0.075).

CONCLUSIONS

Our results suggest that OXC is safe and preserves language function in patients with pediatric epilepsy.

Genetic Knockout of TRPM2 Increases Neuronal Excitability of Hippocampal Neurons by Inhibiting Kv7 Channel in Epilepsy

Epilepsy is a chronic brain disease that makes serious cognitive and motor retardation. Ion channels affect the occurrence of epilepsy in various ways, but the mechanisms have not yet been fully elucidated. Transient receptor potential melastain2 (TRPM2) ion channel is a non-selective cationic channel that can permeate Ca²⁺ and critical for epilepsy. Here, TRPM2 gene knockout mice were used to generate a chronic kindling epilepsy model by PTZ administration in mice. We found that TRPM2 knockout mice were more susceptible to epilepsy than WT mice. Furthermore, the neuronal excitability in the hippocampal CA1 region of TRPM2 knockout mice was significantly increased. Compared with WT group, there were no significant differences in the input resistance and after hyperpolarization of CA1 neurons in TRPM2 knockout mice. Firing adaptation rate of hippocampal CA1 pyramidal neurons of TRPM2 knockout mice was lower than that of WT mice. We also found that activation of Kv7 channel by retigabine reduced the firing frequency of action potential in the hippocampal pyramidal neurons of TRPM2 knockout mice. However, inhibiting Kv7 channel increased the firing frequency of action potential in hippocampal pyramidal neurons of WT mice. The data suggest that activation of Kv7 channel can effectively reduce epileptic seizures in TRPM2 knockout mice. We conclude that genetic knockout of TRPM2 in hippocampal CA1 pyramidal neurons may increase neuronal excitability by inhibiting Kv7 channel, affecting the susceptibility to epilepsy. These findings may provide a potential therapeutic target for epilepsy.

Psychobehavioural and Cognitive Adverse Events of Anti-Seizure Medications for the Treatment of Developmental and Epileptic Encephalopathies

The developmental and epileptic encephalopathies encompass a group of rare syndromes characterised by severe drug-resistant epilepsy with onset in childhood and significant neurodevelopmental comorbidities. The latter include intellectual disability, developmental delay, behavioural problems including attention-deficit hyperactivity disorder and autism spectrum disorder, psychiatric problems including anxiety and depression, speech impairment and sleep problems. Classical examples of developmental and epileptic encephalopathies include Dravet syndrome, Lennox-Gastaut syndrome and tuberous sclerosis complex. The mainstay of treatment is with multiple anti-seizure medications (ASMs); however, the ASMs themselves can be associated with psychobehavioural adverse events, and effects (negative or positive) on cognition and sleep. We have performed a targeted literature review of ASMs commonly used in the treatment of developmental and epileptic encephalopathies to discuss the latest evidence on their effects on behaviour, mood, cognition, sedation and sleep. The ASMs include valproate (VPA), clobazam, topiramate (TPM), cannabidiol (CBD), fenfluramine (FFA), levetiracetam (LEV), brivaracetam (BRV), zonisamide (ZNS), perampanel (PER), ethosuximide, stiripentol, lamotrigine (LTG), rufinamide, vigabatrin, lacosamide (LCM) and everolimus. Bromide, felbamate and other sodium channel ASMs are discussed briefly. Overall, the current evidence suggest that LEV, PER and to a lesser extent BRV are associated with psychobehavioural adverse events including aggressiveness and irritability; TPM and to a lesser extent ZNS are associated with language impairment and cognitive dulling/memory problems. Patients with a history of behavioural and psychiatric comorbidities may be more at risk of developing psychobehavioural adverse events. Topiramate and ZNS may be associated with negative effects in some aspects of cognition; CBD, FFA, LEV, BRV and LTG may have some positive effects, while the remaining ASMs do not appear to have a detrimental effect. All the ASMs are associated with sedation to a certain extent, which is pronounced during uptitration. Cannabidiol, PER and pregabalin may be associated with improvements in sleep, LTG is associated with insomnia, while VPA, TPM, LEV, ZNS and LCM do not appear to have detrimental effects. There was variability in the extent of evidence for each ASM: for many first-generation and some second-generation ASMs, there is scant documented evidence; however, their extensive use suggests favourable tolerability and safety (e.g. VPA); second-generation and some third-generation ASMs tend to have the most robust evidence documented over several years of use (TPM, LEV, PER, ZNS, BRV), while evidence is still being generated for newer ASMs such as CBD and FFA. Finally, we discuss how a variety of factors can affect mood, behaviour and cognition, and untangling the associations between the effects of the underlying syndrome and those of the ASMs can be challenging. In particular, there is enormous heterogeneity in cognitive, behavioural and developmental impairments that is complex and can change naturally over time; there is a lack of standardised instruments for evaluating these outcomes in developmental and epileptic encephalopathies, with a reliance on subjective evaluations by proxy (caregivers); and treatment regimes are complex involving multiple ASMs as well as other drugs.

Social cognition in children and adolescents with epilepsy: A meta-analysis

Many studies have investigated impairments in two key domains of social cognition (theory of mind [ToM] and facial emotion recognition [FER]) in children and adolescents with epilepsy. However, inconsistent conclusions were found. Our objective was to characterize social cognition performance of children and adolescents with epilepsy. A literature search was conducted using Web of Science, PubMed, and Embase databases. The article retrieval, screening, quality assessment (Newcastle-Ottawa-Scale), and data extraction were performed independently by two investigators. A random-effects model was used to examine estimates. The meta-analysis included 19 studies, with a combined sample of 623 children and adolescents with epilepsy (mean [SD] age, 12.13 [2.62] years; 46.1% female) and 677 healthy controls [HCs]) (mean [SD] age, 11.48 [2.71] years; 50.7% female). The results revealed that relative to HCs, children and adolescents with epilepsy exhibited deficits in ToM (g = -1.08, 95% CI [-1.38, -0.78], p < 0.001, the number of studies [k] = 13), FER (g = -0.98, 95% CI [-1.33, -0.64], p < 0.001, k = 12), and ToM subcomponents (cognitive ToM: g = -1.04, 95% CI [-1.35, -0.72], p < 0.001, k = 12] and affective ToM: g = -0.73, 95% CI [-1.12, -0.34], p < 0.001, k = 8). In addition, there were no statistically significant differences in social cognition deficits between children and adolescents with focal epilepsy and generalized epilepsy. Meta-regressions confirmed the robustness of the results. These quantitative results further deepen our understanding of the two core domains of social cognition in children and adolescents with epilepsy and may assist in the development of cognitive interventions for this patient population. Systematic review registration: https://inplasy.com/inplasy-2022-3-0011/, identifier INPLASY202230011.