Definition of drug resistant epilepsy: consensus proposal by the ad hoc Task Force of the ILAE Commission on Therapeutic Strategies

Can transcutaneous auricular vagus nerve stimulation be considered a viable adjuntive therapy in drug-resistant epilepsy? A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

Transcutaneous auricular vagal nerve stimulation (tVNS) has been investigated as a potential non-invasive therapy in addition to standard medical care in patients with drug-resistant epilepsy (DRE). This meta-analysis evaluates the efficacy and safety of tVNS compared to sham stimulation in patients with DRE.

METHODS

A systematic search was conducted in three electronic databases (PubMed, Scopus, Cochrane) to identify randomized controlled trials (RCTs) comparing tVNS versus sham stimulation for the treatment of DRE. The Cochrane risk of bias tool for randomized trials was utilized for quality assessment.

RESULTS

Four RCTs, comprising 368 patients, with 232 patients in the tVNS group, were included. The meta-analysis revealed that tVNS significantly reduces seizure frequency, as expressed by mean monthly seizure number (mean difference [MD] -3.01, 95 % confidence interval [CI] [-5.37 to -0.65], p < 0.01, I2 = 0 %) and percentage seizure reduction (MD 17.57 %, 95 % CI [1.90 to 33.25], p = 0.03, I2 = 0 %) at the end of treatment. The analysis also indicated a potential effect on responder rate (odds ratio 2.00, 95 % CI [0.98 to 4.05], p = 0.06, I2 = 42 %), although not statistically significant. No significant differences between groups were found regarding seizure freedom, depression, and QOL. Adverse events reported were mostly mild and transient, with no significant differences between groups and comparable discontinuation rates.

CONCLUSIONS

This meta-analysis supports the efficacy and safety of tVNS as an adjunctive therapy for the treatment of DRE. Due to significant methodological concerns in some of the included studies, well-designed RCTs are needed to investigate the efficacy of tVNS on seizure and non-seizure outcomes in patients with DRE.

Association of node assortativity and internalizing symptoms with ketogenic diet effectiveness in pediatric patients with drug-resistant epilepsy

BACKGROUND

The ketogenic diet (KD) is an effective alternative therapy for drug-resistant epilepsy (DRE). However, there are no established predictors for KD effectiveness. We aimed to investigate the impact of 12 months of KD therapy (KDT) on brain connectivity, as measured by functional magnetic resonance imaging (fMRI), and its correlation with seizure control, behavioral/mood alterations, and parental stress.

METHODS

Children with DRE were enrolled in this single-center, prospective cohort study from February 2020 to October 2021. They were divided into a control group and a KDT group. The Child Behavior Checklist (CBCL) and Parental Stress Index (PSI) were administered to parents at the initiation of KDT (T0) and at 12 months (T1). Resting-state fMRI was performed at T0 and at 6 months of KDT. The primary outcome was the between-group difference in the change of CBCL/PSI scores, and brain connectivity metrics after KDT, and the secondary outcome involved measuring their correlation with seizure reduction rates.

RESULTS

Twenty-two patients with DRE were enrolled. We had 13 patients in the control group and 9 in the KDT group. Our data revealed that 12 months of KDT can reduce monthly seizure frequency. Several subscales of CBCL T-scores were higher at T0 compared with the control group, then becoming comparable at T1. The PSI scores from 'mothers' reports reduced after receiving KDT. The changes in node assortativity (ΔAssortativity) were positively correlated with behavioral problems and negatively with seizure reduction rates in the KD group.

CONCLUSIONS

Twelve months of KDT can reduce monthly seizure frequency and improve mood/behavioral disturbances in patients with DRE. Furthermore, KDT could relieve primary caregivers' stress. A lower ΔAssortativity value was associated with better behavioral outcomes and greater seizure reduction. The ΔAssortativity value in fMRI may be a crucial predictor for the effectiveness of KDT.

Association between metabolic patterns in 18-FDG PET-CT scan and postsurgical seizure outcomes in patients with temporal lobe epilepsy

INTRODUCTION

Temporal lobe epilepsy (TLE) is the most common type of drug-resistant epilepsy in adults, and surgery is a standard treatment, offering seizure freedom in 60-70 % of patients. Despite advanced imaging, many TLE patients show inconsistent MRI findings, making functional imaging such as 18-FDG PET-CT scans essential in identifying epileptogenic zones. This study aims to assess the association between concordant or non-concordant metabolic patterns in presurgical 18-FDG PET-CT scans and postoperative outcomes in TLE patients.

METHODS

This retrospective, observational study included people with epilepsy (PWE) who underwent TLE surgery at a clinic in Mexico City and had a presurgical 18-FDG PET-CT scan. Seizure outcomes were measured using Engel and ILAE classifications at a two-year follow-up. The concordant group had only temporal hypometabolism ipsilateral to the epileptogenic zone, while the non-concordant group had normal, extratemporal, or bitemporal hypometabolism.

RESULTS

The study included 49 PWE: 28 with concordant PET-CT scans and 21 with non-concordant scans. Comparisons of seizure outcomes using the Engel and ILAE classifications at two years post-surgery revealed no significant differences between the groups (p = 0.972 and p = 0.279, respectively). The use of anti-seizure medications (ASM) after surgery did not differ significantly between groups (p = 0.649).

CONCLUSION

At our center, preoperative evaluation emphasizes the alignment of clinical findings, video-EEG, and MRI. At the two-year follow-up, no significant difference in seizure freedom was observed between patients with temporal lobe hypometabolism alone and those with other patterns.

Sociodemographic barriers in epilepsy surgery in the United States: A systematic review and meta-analysis

OBJECTIVES

The aim of this study was to perform a systematic review and meta-analysis to identify sociodemographic barriers that could contribute to the underutilization of epilepsy surgery.

METHODS

PubMed, EMBASE, and Web of Science databases were systematically reviewed from January 2002 until August 2024. The studies examining the impact of sociodemographic barriers on epilepsy surgery were included. The primary outcomes were the odds ratio (OR) and 95 % confidence intervals (CI) for receiving surgery compared to not-receiving surgery in persons with epilepsy. Race/ethnicity, sex, and insurance had sufficient data to perform a meta-analysis of OR and 95 % CI.

RESULTS

Overall, 1,520,813 patients from 12 studies were evaluated, among which relevant studies were selected for comparing sex (338,170 males and 341,821 females), race (1,056,571 White, 224,693 Hispanic, and 239,549 Black/African-American [Black/AA]), and insurance (232,908 private, 190,849 Medicaid, and 204,478 Medicare). Black/AA patients were significantly less likely to have surgery compared to Whites (OR 0.46, CI 0.35-0.61) or Hispanics (OR: 0.54, CI 0.43-0.67). White patients were more likely to have surgery than other groups examined (OR 1.61, CI 1.28-2.02). There were no significant differences in surgical odds when comparing males to females (OR 1.00, CI 0.97-1.03). Compared to the private insurance, patients with Medicaid (OR 0.61, CI 0.49-0.75) or Medicare (OR: 0.49, CI 0.32-0.77) were less likely to obtain surgery.

CONCLUSION

This meta-analysis highlights the impact of race/ethnicity, sex, and insurance status in the likelihood of receiving epilepsy surgery and can inform targeted interventions and policies aimed at ensuring equity for disadvantaged groups.

Neuropsychiatric disorders in Chinese pediatric tuberous sclerosis complex patients associated with drug-resistant epilepsy: A TAND checklist-based survey

Tuberous sclerosis complex (TSC) is an autosomal-dominant genetic disorder frequently accompanied by neuropsychiatric disorders, especially in patients who have drug-resistant epilepsy (DRE). This study aimed to evaluate the distribution of neuropsychiatric disorders in Chinese children with TSC-related epilepsy using the TAND (Tuberous Sclerosis Complex Associated Neuropsychiatric Disorders) checklist, comparing those with DRE to those achieving seizure freedom. A total of 47 children, aged 6 to 18 years, diagnosed with TSC at Peking University People's Hospital, participated in this cross-sectional study. All participants met the latest diagnostic criteria for TSC. Based on the definition of drug-resistant epilepsy, participants were categorized into DRE group and seizure-free group. Neurodevelopmental disorders were evaluated using the TAND checklist. The study found that 66 % of participants exhibited varying degrees of intellectual disability, with the DRE group demonstrating significantly poorer performance in intelligence, behavior, neuropsychological, and learning skills compared to the seizure-free group. The DRE group also had higher rates of attention-deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD), alongside greater impairments in psychosocial functioning. This study indicates that DRE is strongly associated with neuropsychiatric development in children with TSC, but also that all children with TSC are at increased risk of TAND. Our findings highlight the importance of regular assessment and intervention to support TAND and improve quality of life in this vulnerable group.

Vagal Nerve Stimulation in the Pediatric Population and Correlation between Family and Treatment Team Perspectives: Single-Center Experience

BACKGROUND

 Vagal nerve stimulation (VNS) is an adjunctive therapy to pharmacologic treatment in patients with drug-resistant epilepsy. This study aimed to assess the efficacy of VNS therapy for seizure frequency reduction and improving the quality-of-life (QOL) measures in children with refractory epilepsy and to evaluate the correlation between the perspectives of families and those of the treating team.

METHODS

 This was a prospective cohort study conducted at Abha Maternity and Children's Hospital, Saudi Arabia, from 2018 to 2022. A total of 21 pediatric patients who completed 1 year of follow-up after VNS implantation were included. Patients were aged between 2 and 14 years, with a mean age of 8.14 ± 3.92 years; 11 (52.4%) patients were females. Family and physician assessments were collected blinded to each other using the Clinical Global Impression of Improvement (CGI-I) scores and QOL assessments to evaluate the correlation between the families' and treating team's perspectives on VNS outcomes.

RESULTS

 In this study, VNS showed significant efficacy in reducing the frequency of seizures. VNS significantly reduced the number of seizures per week from a baseline median of 35 to a median of 0.25 at the end of the follow-up period, representing a dramatic reduction of 99.3% (p < 0.001). The number of emergency department visits per year decreased from a baseline median of 12 to a median of 2, a reduction of 83.3% (p < 0.001), while the number of hospital admissions per year decreased from a baseline median of 3 to a median of 1, a 66.7% decrease (p < 0.001). The number of antiepileptic medications taken decreased from a median of four to three (p < 0.001). Notably, 28.57% of the patients achieved complete seizure freedom, and 38% exhibited significant improvement, with at least 50% reduction in seizure frequency. Importantly, none of the patients experienced an increase in seizure frequency following VNS treatment. The family and physician assessments showed varying degrees of alignment in perceptions, with "concentration" exhibiting a significant positive correlation (r = 0.498, p = 0.022), indicating noteworthy agreement, whereas verbal communication did not show a substantial correlation (r = - 0.062, p = 0.791), indicating a divergence of views.

CONCLUSION

 VNS is a promising and well-tolerated therapy for individuals with intractable seizures, offering clinical benefits and potential enhancements in various aspects of QOL. The varying perceptions between family and physician assessments highlight the importance of considering multiple perspectives when evaluating treatment outcomes.

Exploring the Effectiveness of Adjunctive Cenobamate in Focal Epilepsy: A Time-Based Analysis

BACKGROUND

A growing body of evidence supports the effectiveness of cenobamate (CNB). This study aimed to assess the clinical response to add-on CNB through a time-to-event approach and explore the potential contribution of the concomitant classes of antiseizure medications (ASMs) to improve CNB clinical use.

PATIENTS AND METHODS

This study is a subgroup analysis of a larger retrospective, multicenter study on adults with focal-onset seizures participating in the Italian Expanded Access Program at five pre-established centers. The primary endpoint was the time-to-baseline seizure count; secondary endpoints included the rates of seizure response, seizure freedom (defined as no seizures' occurrence since at least the previous follow-up visit), treatment discontinuation, and adverse events (AEs).

RESULTS

Data on 92 participants were extracted, with a median age of 44 (first quartile (Q1)-third quartile (Q3): 29.25-50.75) years. The number of seizures recorded during the 90-day baseline was reached by 59/92 (64.1%) subjects during the 12-month follow-up. A higher, but not statistically significant probability of reaching the baseline seizures count was shown in the subgroups of subjects taking CNB with sodium channel blockers (SCBs) (hazard ratio [HR] 2.75; 95% confidence interval [CI] 0.79-9.61, p = 0.112) and both SCBs and GABAergics (HR 1.48; 95% CI 0.43-5.09, p = 0.536) compared with subjects taking GABAergics without SCBs. At 12 months, the rates of seizure response, seizure-freedom, and treatment discontinuation were 42.0%, 13.6%, and 23.9%, respectively. A total of 47/92 (51.1%) subjects experienced AEs (mainly somnolence, dizziness, and balance disorders) at a median time of 61 (Q1-Q3: 30-101) days. There was a higher, but not statistically significant risk of AEs occurrence in subjects treated with both SCBs and GABAergics and in those taking SCBs without GABAergics (HR 2.24; 95% CI 0.51-9.82, p = 0.286 and HR 1.40; 95% CI 0.31-6.39, p = 0.661, respectively) compared with those taking GABAergics without SCBs. The main limitations are the retrospective design and the small sample size.

CONCLUSIONS

This time-to-event analysis added new insights to the currently available evidence about the real-world effectiveness of add-on CNB. Explorative estimates suggested favorable trends for subjects treated with concomitant GABAergics and without SCBs, who seemed to reach baseline seizure count and experience AEs less frequently and later than subjects treated with other concomitant ASMs. Further studies are needed to identify the best combinations of CNB with other ASMs to maximize seizure control and tolerability.

Prediction of Pharmacoresistance in Drug-Naïve Temporal Lobe Epilepsy Using Ictal EEGs Based on Convolutional Neural Network

Approximately 30%-40% of epilepsy patients do not respond well to adequate anti-seizure medications (ASMs), a condition known as pharmacoresistant epilepsy. The management of pharmacoresistant epilepsy remains an intractable issue in the clinic. Its early prediction is important for prevention and diagnosis. However, it still lacks effective predictors and approaches. Here, a classical model of pharmacoresistant temporal lobe epilepsy (TLE) was established to screen pharmacoresistant and pharmaco-responsive individuals by applying phenytoin to amygdaloid-kindled rats. Ictal electroencephalograms (EEGs) recorded before phenytoin treatment were analyzed. Based on ictal EEGs from pharmacoresistant and pharmaco-responsive rats, a convolutional neural network predictive model was constructed to predict pharmacoresistance, and achieved 78% prediction accuracy. We further found the ictal EEGs from pharmacoresistant rats have a lower gamma-band power, which was verified in seizure EEGs from pharmacoresistant TLE patients. Prospectively, therapies targeting the subiculum in those predicted as "pharmacoresistant" individual rats significantly reduced the subsequent occurrence of pharmacoresistance. These results demonstrate a new methodology to predict whether TLE individuals become resistant to ASMs in a classic pharmacoresistant TLE model. This may be of translational importance for the precise management of pharmacoresistant TLE.

Laser Interstitial Thermal Therapy for the Treatment of Mesial Temporal Lobe Epilepsy in Children

ObjectiveFew studies have explored the efficacy of laser interstitial thermal therapy in pediatric epilepsy surgery. This study aims to evaluate seizure-free outcomes in children and adolescents with mesial temporal lobe epilepsy who underwent laser interstitial thermal therapy.MethodsThis was a retrospective cohort study performed at a level 4 epilepsy center. All patients had comprehensive presurgical epilepsy evaluations with a consensus treatment decision made by a multidisciplinary team. Brain magnetic resonance imaging (MRI) data were used to determine lesional vs nonlesional groups. All laser interstitial thermal therapy procedures were performed using Visualase laser ablation systems by the neurosurgical team. Seizure-free outcomes were measured according to the Engel surgical outcome scale.ResultsThis study included 19 patients (12 girls, 7 boys). Age of epilepsy onset ranged from 2 to 17 years (mean 9.9 years), and age at time of surgery ranged from 8 to 20 years (mean 15.1 years). Ten patients (52.5%) had signs of hippocampal sclerosis on MRI (lesional group), and 9 patients (47.5%) had a normal brain MRI (nonlesional group). Engel 1 score was achieved by 14 of 19 patients (73.5%): 9 of 10 patients (90%) in the lesional group and 5 of 9 patients (55.5%) in the nonlesional group. Younger age of seizure onset was a predictor of better postsurgical outcome, but no other outcome predictors could be established.ConclusionLaser interstitial thermal therapy is safe and effective for the treatment of drug-resistant mesial temporal lobe epilepsy in children, rendering more favorable seizure-free outcomes in pediatric patients with hippocampal atrophy than in those with nonlesional mesial temporal lobe epilepsy.

Altered neural avalanche spreading in people with drug-resistant epilepsy✰

OBJECTIVE

To characterize a peculiar "EEG endophenotype" of drug-resistant epilepsy (DRE) through the graph theory characterization of avalanche spatiotemporal spreading properties.

METHODS

We performed avalanche analysis and computed avalanche transition matrices (ATMs) on 19-channel scalp EEG of 120 people with epilepsy (60 DRE and 60 non-DRE) who assumed two anti-seizure medications, comparing such results with a group of 40 healthy subjects (HS). Network topologies of ATMs were characterized through graph theory metrics. We performed an analysis of variance to compare aperiodic metrics between HS, DRE and non-DRE. Logistic regression was performed to test and compare the ability of graph theory metrics on ATM and clinical features to correctly discriminate the PwE group according to the clinical outcome (DRE or non-DRE).

RESULTS

DRE exhibited a peculiar altered avalanche spreading as proved by the higher mean betweenness centrality, the longer characteristic path length and the lower small-world index (more regular and less plastic network topology) of ATMs than non-DRE and HS (p-values from <0.001 to 0.05). Graph metrics on ATMs significantly improved the yield of detecting DRE and contributed the most to the model accuracy (0.83) than clinical features. Resting-state EEG activity of HS and PwE did not deviate from the characteristics of a system operating at criticality.

CONCLUSIONS

ATMs detect alterations of resting-state networks peculiar to the DRE condition.

SIGNIFICANCE

These findings could open new scenarios for the future identification of promising biomarkers of DRE through scalp EEG.

Distinct gray matter and metabolic characteristics in hypothalamic hamartoma network with different semiology

OBJECTIVE

Hypothalamic hamartomas (HHs) are developmental malformations associated with focal epilepsy. We investigated the patterns of gray matter morphology and cerebral metabolism in individuals with HHs, with and without focal to bilateral tonic-clonic seizures (FBTCSs), aiming to clarify the accompanying network abnormalities.

METHODS

We analyzed magnetic resonance imaging (MRI) and fluorodeoxyglucose positron emission tomography (PET) data from 59 patients with HHs (28 with FBTCSs, 31 without), as well as MRI data from 30 healthy controls (HCs) and PET data from 45 HCs. We assessed gray matter voxel-based morphometry and quantitative analysis of cerebral glucose uptake in HH patients and controls, with age, sex, and total intracranial volume as covariates, and drew correlations with duration of epilepsy and seizure semiology and frequency.

RESULTS

Compared to HCs, HH patients had significantly increased gray matter volume (GMV) in the ipsilateral amygdala, piriform cortex, hypothalamus, and bilateral temporal cortices; patients with FBTCSs primarily showed increased GMV in the HH stalk, whereas those without FBTCSs showed increased GMV prominently in the amygdala. GMVs of amygdala and piriform cortex were greater and the ipsilateral midtemporal cortex was more hypometabolic the longer the duration of epilepsy and the greater the seizure frequency. No significant GMV or cerebral glucose uptake differences were found between HH patients with and without FBTCSs.

SIGNIFICANCE

HH-related epilepsy is a network disorder characterized by widespread abnormalities beyond the lesion. This highlights the importance of considering the whole network when formulating diagnosis and treatment plans.

Dataset of long-term multi-site LFP activity with spontaneous chronic seizures in temporal lobe epilepsy rats

The characteristics of refractory epilepsy change with disease progression. However, relevant studies are scarce due to the difficulty in obtaining long-term multi-site data from patients with epilepsy. This work aimed to provide a long-term brain electrophysiological dataset of 15 pilocarpine-treated rats with temporal lobe epilepsy (TLE). The dataset was constituted by multi-site local field potential (LFP) signal recorded from 12 sites in the Papez circuit in TLE, including spontaneous seizures and interictal fragments in the chronic period. The LFP data were saved in MATLAB, stored in the Neurodata Without Borders format, and published on the DANDI Archive. We validated the dataset technically through specific signal analysis. In addition, we provided MATLAB codes for basic analyses of this dataset, including power spectral analysis, seizure onset pattern identification, and interictal spike detection. This dataset could reveal how the electrophysiological and epileptic network properties of the brain of rats with chronic TLE changed during epilepsy development, thus help inform the design of adaptive neuromodulation for epilepsy.

Impact of epilepsy surgery on the adaptive behavior of children with drug-resistant epilepsy

OBJECTIVE

This study was undertaken to assess the impact of surgical treatment on the adaptive abilities of children with drug-resistant epilepsy (DRE) and moderate or severe developmental delays, and to identify factors that could potentially predict adaptive outcomes following epilepsy surgery.

METHODS

A retrospective observational cohort study was conducted involving 130 pediatric patients with DRE treated in the Ribeirão Preto Epilepsy Surgery Program of the University of São Paulo between 1996 and 2019. Patients underwent comprehensive preoperative evaluations, including neurological, psychiatric, social, and neuropsychological assessments using the Vineland Adaptive Behavior Scale. Adaptive functioning was assessed at three time points: before surgery and approximately 15 months and 34 months after surgery. Seizure outcomes were classified using the Engel scale. Statistical analyses included analysis of variance, Spearman correlation, and general linear model for repeated measures.

RESULTS

Before surgery, patients exhibited severe adaptive delays, with an average age equivalence (AE) of 18.2 months compared to an average chronological age of 78 months. Postoperatively, significant improvements in AE were observed, particularly among patients who achieved seizure freedom (Engel class I). At the first postoperative evaluation (median of 15 months after surgery), the average AE increased to 24.1 months (p < .01). At the second postoperative evaluation (median of 34 months after surgery), the average AE further increased to 27.5 months. Seizure-free patients demonstrated greater improvements in adaptive skills compared to those who continued to experience seizures (F = 5.845, p = .018) SIGNIFICANCE: This study reinforces that epilepsy surgery can lead to significant adaptive improvements in children with DRE, including those with severe neurological impairments. The findings highlight the positive impact of seizure freedom on developmental progress and underscore the importance of early intervention to minimize adaptive delays.

Identification and enrichment of potential pathways in the buffy coat of patients with DRE using non-targeted metabolomics integrated with GEO Datasets

BACKGROUND

This study aims to identify potential biomarkers in the buffy coat of drug-resistant epilepsy (DRE) patients with mesial temporal lobe epilepsy and to elucidate associated pathways.

METHODS

A comprehensive non-targeted metabolomic and Gene Expression Omnibus (GEO) datasets analysis was first performed on buffy coat from DRE patients and non-epilepsy (CON) patients. Potential enriched biomarkers and pathways were integrated with gene expression profiles from GEO datasets to identify robust biomarkers.

RESULTS

In the DRE group, there were 15 patients (10 males and 5 females), with an average age of (37.67 ± 15.53) years. In the CON group, there were 10 patients (7 males and 3 females), with an average age of (51.60 ± 18.20) years. A total of 27 potential biomarkers were identified, including 7 down-regulated and 8 up-regulated. Additionally, 9 potential pathways related to DRE were identified. Notably, purine metabolism, tryptophan metabolism and aminoacyl-tRNA metabolism were closely related to DRE. Purine metabolism was up-regulated, while aminoacyl-tRNA and tryptophan metabolism were down-regulated.

CONCLUSIONS

The integration of metabolomic data with GEO datasets analysis offers a new strategy to identify robust biomarkers and pathways. The findings obtained from the buffy coat analysis offer potential insights for the diagnosis and treatment of DRE.

Mediating effects of anxiety and depression on the relationship between somatic symptom disorder and quality of life among adults with epilepsy

OBJECTIVE

Although quality of life (QOL) is impaired in patients with somatic symptom disorder (SSD), little is known about the relationship between SSD and QOL among patients with epilepsy (PWE) and the mechanisms underlying this association. This study aimed to identify the mediators of the association between SSD and QOL among PWE.

METHODS

A cross-sectional study was conducted at West China Hospital between July 2020 and May 2022. A total of 749 adults with epilepsy who attended the epilepsy center were consecutively enrolled via convenience sampling. All patients completed questionnaires that assessed demographic and clinical features, the Somatic Symptom Disorder-B Criteria Scale (SSD-12), the Patient Health Questionnaire-9 (PHQ-9), the Generalized Anxiety Disorder-7 (GAD-7), the Quality of Life in Epilepsy Inventory-31 (QOLIE-31), and the National Hospital Seizure Severity Scale (NHS3). The direct, indirect, and total effects of the predictors on QOL among PWE were tested based on the bootstrap method.

RESULTS

Up to 24.43 % of the adults with epilepsy were affected by SSD. Patients with SSD had significantly higher levels of depression and anxiety and lower levels of QOL. Correlation and mediation analyses revealed that the negative relationship between SSD and QOL was partially mediated by depression and anxiety (B = -10.412, 95 % CI [-12.730, -8.343]). The indirect effect accounted for 66.76 % of the total effect, among which depression accounted for a greater proportion (46.37 %).

CONCLUSION

This study offers new insight into the mechanism underlying the association between SSD and QOL among PWE. Interventions aimed at increasing QOL in patients with somatic symptoms should consider screening and treating depression and anxiety.

Adjunctive use of cannabidiol in pediatric drug-resistant epilepsy: A retrospective multicenter analysis

BACKGROUND

Epilepsy affects approximately 70 million people globally, with one-third experiencing drug-resistant epilepsy (DRE). Cannabidiol (CBD) has shown promise in reducing seizure frequency for specific epilepsy syndromes, though data for broader etiologies remain limited. The goal of the study is to evaluate the effectiveness of CBD as an adjunct treatment in the reduction of seizure frequency in DRE patients of various etiologies.

METHODS

We conducted a retrospective chart review of patients with refractory epilepsy who received a CBD as an adjunct treatment at two tertiary care centers. Seizure frequency at the start of CBD treatment and at a minimum follow-up of 3 months was recorded. Epilepsy diagnosis was categorized into five groups: Focal/Multifocal Epilepsy, Primary Generalized Epilepsy, Lennox-Gastaut Syndrome, Dravet Syndrome, and Other Developmental and Epileptic Encephalopathies.

RESULTS

Among all patients, 49 % achieved a ≤ 25 % reduction in seizures, while 5 % had a 26-50 % reduction, 21 % reached a 51-75 % reduction, 20 % experienced a 76-99 % reduction, and 5 % achieved near seizure freedom. There was a significant reduction in median seizure frequency from 30 at baseline to 8 post-treatment (p = 0.000). Significant reductions in seizure frequency were also observed within each diagnostic category.

DISCUSSION

CBD has proven to be an effective adjunctive treatment for medically refractory epilepsy, showing significant efficacy across various epilepsy etiologies and genetic backgrounds. Its ability to reduce seizure frequency and the burden of anti-seizure medications (ASMs), especially in syndromes that are traditionally difficult to manage, highlights its value as an additional therapeutic option.

Multimodal prognostication of autoimmune encephalitis: an Australian autoimmune encephalitis consortium study

BACKGROUND AND OBJECTIVES

To identify factors predictive of a favourable modified Rankin score (mRS) at 12 months in patients with autoimmune encephalitis (AE). To evaluate predictors of a binary composite clinical-functional outcome measure, encompassing mRS, drug-resistant epilepsy (DRE) and memory impairment, at 12 months.

METHODS

Univariable and multivariable logistic regression analyses for predictors of a favourable mRS (i.e. mRS ≤ 2) and a composite clinical-functional outcome at 12 months were used.

RESULTS

A total of 231 patients with AE were recruited. Multivariable logistic regression identified factors predictive of reduced odds of favourable mRS at 12 months were older age (OR 0.97; 95% CI 0.95, 0.98; p < 0.001), T2/FLAIR hyperintensity on initial MRI (OR 0.27; 95% CI 0.13, 0.56; p < 0.001), RSE (OR 0.17; 95% CI 0.06, 0.52; p = 0.002) and first-line immunotherapy failure (OR 0.18; 95% CI 0.09, 0.37; p < 0.001). Anti-LGI1 antibody-mediated encephalitis relative to other subtypes (OR 4.46; 95% CI 1.55, 12.80; p = 0.006) was associated with a better 12-month mRS. We found concordant associations for a composite outcome at 12 months, with the addition of a diagnosis of definite autoimmune limbic encephalitis (AILE) predicting a poor outcome.

DISCUSSION

Older age, MRI T2/FLAIR hyperintensity, RSE and first-line immunotherapy failure predicted worse mRS and composite clinical-functional outcome at 12 months, while a diagnosis of anti-LGI1 antibody-mediated encephalitis was associated with favourable outcomes. Our data highlight acute clinical factors predictive of a more severe clinical and functional course at 12 months.

Cannabidiol in Drug-Resistant Epilepsy (DRE) in Children: A Retrospective Study

OBJECTIVES

To describe the effectiveness and tolerability of cannabidiol (CBD) in children with drug-resistant epilepsy (DRE).

METHODS

Records of children with DRE who received CBD for at least six months were reviewed. Reduction in seizure frequency [complete (> 90%), partial (30-90%), no response (< 30%)], parent reported adverse effects and discontinuation of CBD, if any, were noted.

RESULTS

Records of 50 children with DRE (Lennox-Gastaut syndrome 32, Dravet syndrome 4, and Tuberous sclerosis complex 2), mean (SD) age 7.8 (4.3) years were reviewed. Complete, partial, and no response to CBD was seen in 10, 18 and 14 children; 8 became seizure-free. Eight children discontinued treatment due to lack of efficacy (n = 4), by increased adverse effects (n = 3) and aggravation of seizures (n = 1). Adverse effects were noted in 22 (44%), none required hospitalization.

CONCLUSION

Cannabidiol is a useful and safe add-on drug in children with DRE.

Optimizing drug-resistant epilepsy identification in the Veterans Health Administration

BACKGROUND

Accurate identification of drug-resistant epilepsy (DRE) is crucial for accurate disease measurement, effective clinical intervention and improved patient outcomes. Prior attempts to define DRE in administrative data using the 2010 International League against Epilepsy (ILAE) criteria have faced complexities.

METHODS

This retrospective study utilized national administrative data from the Veterans Health Administration (VHA) to identify patients with possible DRE. This was a multicenter national cohort that uses a common, non-commercial medical record system. A panel of six epileptologists conducted chart reviews to identify DRE using the 2010 ILAE criteria. Logistic regression was used to analyze epilepsy-related variables of interest to develop algorithms identifying DRE.

RESULTS

Among 260 included patients, 93 (35.8 %) had DRE, 148 (56.9 %) did not have DRE, and 19 (7.3 %) were undetermined. Out of 96 algorithms assessed, the best-performing algorithm had a high accuracy (F1 score=0.726) and defined DRE as those on ≥ 3 ASMs in addition to those on ≥ 2 ASMs for ≥ 365 days with at least one intractable ICD code. The algorithm demonstrated high sensitivity (0.74), specificity (0.81), and area under the curve (AUC 0.78). Factors such as age, number of ASMs, EEG, and MRI procedures, and intractable epilepsy ICD codes were associated with DRE.

DISCUSSION

Our optimal algorithm for DRE identification is like previously published algorithms that determined the importance of number and duration of ASMs. However, it differs in the particular combination of factors that best identified DRE. These differences highlight the importance of fine-tuning algorithms for specific care settings. Further validation in a larger, more heterogenous cohort are needed to determine our algorithm's applicability and potential impact.

A pilot study on the programming protocol of vagus nerve stimulation in children with drug-resistant epilepsy: High pulse amplitude or high duty cycle

OBJECTIVE

To compare the efficacy and safety of vagus nerve stimulation using different modes in patients with drug-resistant epilepsy (DRE).

METHODS

Children with DRE who underwent vagus nerve stimulator implantation between March 2019 and December 2022 were prospectively enrolled at the Peking University First Hospital. Ninety-four children were randomly divided into the high pulse amplitude [pulse amplitude was gradually increased to maximum tolerance value (≤2.8 mA) and duty cycle was maintained at 10%] and high duty cycle groups [pulse amplitude was maintained at 1.5 mA and duty cycle was subsequently increased to maximum tolerance value (≤37%)]. At the 55-week follow-up, the responder rate, seizure-free rate, and adverse effects were compared between the two groups.

RESULTS

Ninety-four children with DRE were included (47 patients each in the high pulse amplitude group and the high duty cycle group). For epileptic seizures, the responder rate of the high pulse amplitude group was 53.2% (25/47), while that of the high duty cycle group was 38.3% (18/47). High pulse amplitude had a higher responder rate of focal seizures (60.7% in the high pulse amplitude group vs. 29.2% in the high duty cycle group; chi-squared test, p = 0.023). Among children with a ≥ 75% reduction in epileptic spasms, the high duty cycle group had a higher responder rate than the high pulse amplitude group (54.5% vs. 16.7%; Fisher's exact test, p = 0.022). In addition, in the high duty cycle group, the responder rate in children with epileptic spasms was higher than that in children without epileptic spasms (59.1% vs. 20.0%; chi-square test, p = 0.011). Among children with implantation age <6 years, the responder rate of the high pulse amplitude group was higher (chi-square test, p = 0.024). The incidence of adverse effects in the two groups was not statistically different.

SIGNIFICANCE

The overall responder rates in the two modes were similar. The high pulse amplitude mode may be more effective for focal seizures, whereas the high duty cycle mode may be more effective for epileptic spasms. Patients aged <6 years with DRE and VNS implantation may require a higher pulse amplitude to achieve better efficacy.

PLAIN LANGUAGE SUMMARY

This study compared the anti-seizure efficacy of two different vagus nerve stimulation (VNS) treatments. We found that the overall efficacy of the two treatments was similar. The high pulse amplitude mode may be more effective for focal seizures, whereas the high duty cycle mode may be more effective for epileptic spasms. Patients aged <6 years with drug-resistant epilepsy (DRE) and VNS treatment may require a higher pulse amplitude to achieve better efficacy.

Invasive Neurostimulation for the Treatment of Epilepsy

Although electricity has been used in medicine for thousands of years, bioelectronic medicine for treating epilepsy has become increasingly common in recent years. Invasive neurostimulation centers primarily around three approaches: vagus nerve stimulation (VNS), responsive neurostimulation (RNS), and deep brain stimulation (DBS). These approaches differ by target (e.g., cranial nerve, cortex, or thalamus) and stimulation parameters (e.g., triggered stimulation or continuous stimulation). Although typically noncurative, these approaches can dramatically reduce the seizure burden and offer patients new treatment options. There remains much to be understood about optimal targets and individualized stimulation protocols. Objective markers of seizure burden and biomarkers that quickly quantify neural excitability are still needed. In the future, bioelectronic medicine could become a curative approach that remodels neural networks to reduce pathological activity.

Subunit specific altered expression and activity of casein kinase 2 in the brain tissues resected from mesial temporal lobe epilepsy with hippocampal sclerosis patients & rodent temporal lobe epilepsy model

INTRODUCTION

Mesial temporal lobe epilepsy (MTLE), is associated with dysregulated excitatory-inhibitory balance in the brain. Numerous enzymes, protein kinases, that are modulated through phosphorylation, have been linked with key processes involved in the pathogenesis of epilepsy. Therefore, in this study, we determined the subunit specific expression and activity of multi-subunit casein Kinase 2 (CK2) which influences NMDARs through phosphorylation events, in MTS patients as well as pilocarpine model of TLE.

METHODS

mRNA expression of CK2 (α, α', β) & NR2B was measured by real time PCR andprotein expression of CK2 (α, α', β), NR2B, and NR2B Ser1480 were evaluated using western blotting and immunohistochemistry in experimental models of TLE and MTS patients. CK2 α and α' activity was measured by kinase assay.

RESULTS

Significant increase in CK2α', CK2β, and NR2B mRNA expression were noted in chronic TLE rat model. Similarly, MTS patients displayed upregulated CK2α' and CK2β expressions, but NR2B mRNA remained unchanged. CK2α', CK2β, and NR2B Ser1480 protein expressions were higher in chronic TLE and MTS patients in relation to controls (p < 0.05), as was kinase activity (p < 0.05). In acute TLE rats, only NR2B protein expression was upregulated (p < 0.05).

CONCLUSION

Our research demonstrated for the first time the upregulation of CK2α' subunit and its increased kinase activityin resected brain samples from MTS patients as well as pilocarpine model of TLE. Altered expression and higher activity of CK2 α' highlights subunit specific contribution, suggesting the modulation of NMDA receptors by Casein Kinase 2 may contribute to hyperexcitability in MTLE.

Efficacy and compliance of carbohydrate-restricted diets for treating drug-resistant epilepsy: A network meta-analysis of randomized controlled trials

BACKGROUND

Drug-resistant epilepsy (DRE) presents a significant clinical challenge since many patients fail to respond adequately to pharmacological treatments, resulting in persistent seizures and a great decline in quality of life. This highlights the urgent need for alternative or adjunctive therapeutic strategies. Carbohydrate-restricted diets have emerged as promising adjunctive treatments for epilepsy. However, while the efficacy of these diets has been well-established in pediatric populations, their effectiveness on adult DRE patients remains underexplored. This study aims to evaluate and compare the efficacy of various carbohydrate-restricted diets in treating DRE among all age groups, providing valuable insights into their potential clinical applications.

METHODS

PRISMA guidelines for network meta-analysis were followed. Randomized controlled trials (RCTs) comparing the efficacy of different carbohydrate-restricted diets in DRE patients, and published in PubMed, Embase, Cochrane, and Web of Science up to 22 December 2023 were screened. The primary outcomes were >50 %, >90 % seizure frequency reduction from the baseline and seizure freedom. Secondary outcomes included compliance and adverse events. Random-effects models with a Bayesian-based approach were employed to estimate between-group comparisons, with results presented as odds ratios (OR) and 95 % credible intervals (CrI).

RESULTS

A total of 17 RCTs involving 1468 DRE patients were included. The diets evaluated were the ketogenic diet (KD), modified Atkins diet (MAD), and low glycemic index treatment (LGIT). For >50 % and >90 % seizure reduction from baseline, all three diets resulted in significant efficacy compared to the normal diet. Notably, MAD was the only diet that demonstrated a statistically significant association with seizure freedom (OR 7.36, 95 % CrI 2.21-60.36), compared to the normal diet, while its lower compliance (OR 0.39, 95 % CrI 0.18-0.76) was likely influenced by the inclusion of adult subjects. Adverse effects were reported across all three diets with similar profiles, highlighting the need for individualized monitoring.

CONCLUSIONS

This meta-analysis indicated that in RCTs, the included diet therapies were overall equivalent in efficacy and side effects, with the MAD showing a higher chance of seizure freedom. Compliance was lower with the MAD, but this was likely due to a preponderance of adult studies using this therapy.

Cannabis derivatives and their synthetic analogs for treatment-resistant epilepsy: A systematic review and meta-analysis

BACKGROUND

Cannabidiol and other synthetic analogs from the Cannabis sativa plant have been investigated as alternative for the treatment of refractory epilepsy.

OBJECTIVE

to assess the effects of cannabis derivatives for the treatment of refractory epilepsy.

SEARCH METHODS

a search of the literature was carried out in the several databases, as well as a manual search of the reference lists of relevant studies, gray literature and clinical trial registries. Selection criteria and analysis: randomized controlled trials were included, and the risk of bias was assessed using the Cochrane risk of bias tool. The certainty of the evidence was assessed using the GRADE approach.

MAIN RESULTS

Seven randomized clinical trials were included. Cannabidiol 20 mg/kg/day and 10 mg/kg/day probably increased the frequency of participants who achieved a ≥ 50 % reduction in monthly seizures (20 mg/kg/day: Relative Risk [RR] 1.92; 95 % 95 %CI 1.49-2.46, n = 575, 4 RCTs; 10 mg/kg/day: RR 1.94; 95 %CI 1.32-2.86, n = 280, 2 RCTs, moderate certainty of evidence). The incidence of serious adverse events is probably increased with CBD 20 mg/kg/day (RR 2.30; 95 %CI 1.36-3.89, n = 583, 4 RCTs, moderate certainty of evidence), and may be increased with CBD 10 mg/kg/day (RR 1.62; 95 %CI 0.92-2.84, n = 272, 2 RCTs; low certainty of evidence). Certainty of evidence for other included interventions ranged from very low to low. Conclusions: For most included comparisons and outcomes, there were uncertainties regarding the effects of cannabinoids. Future RCTs could contribute to a better understanding of the effects of cannabinoids for refractory epilepsy.

Preclinical PET imaging in epileptogenesis: towards identification of biomarkers and therapeutic targets

BACKGROUND

Epilepsy is a neurological disorder that affects a significant portion of the global population. However, its complexity and the lack of biomarkers hinder the study of its etiology, resulting in a lack of effective treatments to slow down or halt disease development, also called epileptogenesis.

MAIN BODY

Animal models have proven to be a crucial tool for studying epileptogenesis, many exhibiting cellular, molecular, and functional alterations that resemble those found in human patients. This review examines preclinical studies that have utilized positron emission tomography, a non-invasive neuroimaging technique that has demonstrated correlation with the pathological features and behavioral comorbidities of the disease and a high predictive value for the severity of epileptogenesis.

CONCLUSION

Positron emission tomography imaging has fostered the knowledge of the mechanisms driving epileptogenesis. This translational technique might be crucial for identifying biomarkers of epilepsy, identifying novel treatment targets and selecting and monitoring patients for potential future therapies.

Efficacy of treating Helicobacter pylori infection on seizure frequency in children with drug-resistant idiopathic generalized epilepsy: a randomized controlled trial

BACKGROUND

Helicobacter pylori (H. pylori) causes chronic infection in more than half of the population worldwide. Accumulating body of evidence indicates the possible role of H. Pylori infection in extra-intestinal health problems, including epilepsy. This study aims to investigate the efficacy of treating H. pylori infection on seizure frequency among children with drug-resistant idiopathic generalized epilepsy (IGE).

METHODS

A parallel, two-arm, open-label, randomized controlled trial was conducted on 126 children with drug-resistant IGE and positive H. pylori stool antigen test who were randomly assigned to study and comparison groups in 1.2:1 ratio. Only the study group received H. pylori eradication therapy (esomeprazole, amoxicillin, and clarithromycin) for two weeks. The primary outcome was seizure improvement (≥ 50% seizure frequency reduction compared with baseline) after 2.5 months. Secondary outcomes were occurrence of status epilepticus, escalation of antiseizure medication (ASMs), and adverse effects. Outcomes between the two groups were compared using Chi-square/Fisher exact tests on an intention-to-treat principle. Logistic regression analysis was performed to investigate possible effects of baseline variables on primary outcome.

RESULTS

Seizure improvement occurred in 23 (33%) children in the study group compared with seven (12%) children in the comparison group (Risk ratio [RR] 2.7, 95% confidence interval [CI]: 1.3-5.9; p 0.006). The study group had lower occurrence of status epilepticus (2.9% vs. 14%; RR 0.21, 95%CI: 0.05-0.93; p 0.042) and lesser need for ASMs escalation (4.4% vs. 19.3%; RR 0.23, 95%CI: 0.07-0.77; p 0.010). Adverse effects were more frequent among subjects in the study group, including nausea (15.9% vs. 10.5%) vomiting (8.7% vs. 3.5%), diarrhea (11.6% vs. 5.3%), and skin rash (4.4% vs. 1.8%), but the differences were not statistically significant (p > 0.05). None of baseline participants' variables was significantly associated with the primary outcome.

CONCLUSION

Treating H. pylori infection may improve seizure control in children with drug-resistant IGE, but further studies are warranted to confirm our findings and explore mechanisms behind seizure improvement following H. pylori eradication therapy.

TRIAL REGISTRATION

Registered on www.

CLINICALTRIALS

gov (identifier: NCT05297695) on 17 March 2022. https://clinicaltrials.gov/study/NCT05297695 .

Cenobamate as add-on treatment in ultra-refractory focal epilepsy: Real-world results from The Danish Epilepsy Centre, Dianalund, Denmark

OBJECTIVES

At The Danish Epilepsy Centre, Dianalund, Denmark, we aimed to assess the long-term efficacy, tolerability profile, and influence on concomitant antiseizure medications (ASMs) of cenobamate as an add-on treatment in patients with ultra-refractory focal epilepsies.

METHODS

Adult patients with ultra-refractory epilepsy (defined as focal epilepsies in which ≥ 6 treatments, including ASM trials, epilepsy surgery, and vagus nerve stimulator, failed to achieve seizure control) treated with add-on cenobamate between October 2021 and June 2024 were included in our retrospective, observational study. Data were collected through electronic patient records and seizure-diaries.

RESULTS

32 patients were included. The mean length of treatment was 21 months (range 2-32 months) and the median dose of cenobamate was 250 mg (range 50-400 mg). Fourteen/32 (44%) patients were responders (≥ 50% reduction in seizure frequency) to cenobamate, including five patients who became seizure-free (15.6% of the total cohort). Eleven/32 (34%) discontinued due to adverse effects (AEs) or lack of efficacy. Patients with active focal-to-bilateral-tonic-clonic seizures remaining on treatment decreased by 50%. The ASM most frequently reduced was lacosamide, while the one most often discontinued was lamotrigine. Fifteen/32 (47%) patients reported at least one AE during the treatment period of 32 months. Two-thirds were resolved by dose-reduction of ASMs or cenobamate. AEs most frequently reported were tiredness and dizziness; the lowest incidence of these AE was found when cenobamate was added as the third drug.

SIGNIFICANCE

Our study underlines the usefulness of cenobamate in treating patients with ultra-refractory epilepsy and indicates its long-term effectiveness in real-world clinical practice.

Association of the cognitive lateralization rating Index with surgical variables of a national cohort of pediatric patients with epilepsy

OBJECTIVE

Surgery is a standard treatment for medically refractory epilepsy, and many factors contribute to determining surgical approaches. The Cognitive Lateralization Rating Index (CLRI) quantifies the degree of dysfunction evident and can suggest atypical neuroanatomical functional organization if dominant skills remain despite left-hemisphere seizure foci (i.e., 'atypically-organized'). We sought to elucidate associations between surgical rate, intent, and procedure type based on CLRI categories.

METHODS

Frequencies and descriptive statistics were run in addition to X2 test of independence and ANOVA evaluating CLRI versus surgical variables. 3-category CLRI included: dominant, non-dominant hemisphere, and non-lateralized dysfunction. 4-catgeory CLRI included the additional 'atypically organized' category.

RESULTS

Of 179 patients with CLRI scores, 139 were offered surgery (78%). Left-hemisphere seizure foci were observed in 51% of patients. There was no relationship between surgery offered and 3-category CLRI (X2 (2, 179) = 0.28, p = 0.88); however, inclusion of atypical organization, was related to surgery offered (X2 (3, 179) = 7.34, p = 0.06). We observed no significant difference between rates of curative or palliative-intent surgery in 3-category (X2 (2, 92) = 0.97, p = 0.62) or 4-category CLRI (X2 (3, 92) = 2.36, p = 0.50). Results trended towards curative procedures (58.7%) with no significant difference between rates of procedures amongst CLRI groups. There was no statistically significant difference between pre- and postoperative cognitive results.

CONCLUSION

Not considering atypical organization may lead to overestimating surgical risk in patients with left-hemisphere seizure foci. While significant differences between surgical offerance, intent, or procedure were not observed, results trended towards significance once consideration of atypical organization was included. Further investigation of these variables in addition to surgical and cognitive outcomes is warranted.

Increased Immunoglobulin and Proteoglycan Synthesis in Resected Hippocampal Tissue Predicts Post-Surgical Seizure Recurrence in Human Temporal Lobe Epilepsy

Background/Objectives: For patients with medically refractory temporal lobe epilepsy (TLE), surgery is an effective strategy. However, post-operative seizure recurrence occurs in 20-30% of patients, and it remains challenging to predict outcomes solely based on clinical variables. Here, we ask to what extent differences in gene expression in epileptic tissue can predict the outcome after resective epilepsy surgery. Methods: We performed RNAseq on hippocampal tissue resected from eight patients who underwent anterior temporal lobectomy with amygalohippocampectomy (ATL/AH), half of whom became seizure free (SF) or non-seizure free (NSF). Results: Bioinformatic analyses revealed 1548 differentially expressed genes and statistical enrichment analyses identified a distinct set of pathways in NSF and SF cohorts that were associated with neuroinflammation, neurotransmission, synaptic plasticity, and extracellular matrix (ECM) reorganization. Resected tissue exhibiting strong pro-inflammatory processes are associated with better post-surgery seizure outcomes than patients exhibiting cellular signaling processes related to ECM reorganization, autoantibody production, and neural circuit formation. Conclusions: The results suggest that post-operative targeting of both inhibitory aspects of the ECM remodeling and the autoimmune/inflammatory components may be helpful in promoting repair and preventing the recurrence of seizures.

Risk of Poststroke Epilepsy Among Young Adults With Ischemic Stroke or Intracerebral Hemorrhage

Importance

Poststroke epilepsy (PSE) is a major complication among young adults and is associated with problems with functional recovery and daily life. Although scores have been developed to predict risk of PSE, they have not been validated among patients with stroke at a young age.

Objectives

To investigate both the risk of and risk factors for PSE at a young age and validate current PSE risk scores among a cohort of young adults.

Design, Setting, and Participants

This cohort study used data from ODYSSEY (Observational Dutch Young Symptomatic Stroke Study), a prospective cohort study conducted among 17 hospitals in the Netherlands between May 27, 2013, and March 3, 2021, with follow-up until February 28, 2024. Participants included 1388 consecutive patients aged 18 to 49 years with neuroimaging-proven ischemic stroke or intracerebral hemorrhage (ICH) and without a history of epilepsy. Statistical analysis took place between June and August 2024.

Exposure

First-ever neuroimaging-proven ischemic stroke or ICH.

Main Outcomes and Measures

Poststroke epilepsy was defined as at least 1 remote symptomatic seizure (>7 days). Cumulative incidence functions were used to calculate the 5-year risk of PSE. Fine-Gray regression models were used to identify risk factors associated with PSE (age, sex, clinical stroke, and neuroimaging variables). The performances of the SeLECT (severity of stroke, large-artery atherosclerosis, early seizure, cortical involvement, and territory of middle cerebral artery) 2.0 risk score (for ischemic stroke) and the CAVE (cortical involvement, age, bleeding volume, and early seizure) risk score (for ICH) were assessed with C statistics and calibration bar plots.

Results

This study included 1388 patients (ischemic stroke, 1231 [88.7%]; ICH, 157 [11.3%]; median age, 44.1 years [IQR, 38.0-47.4 years]; 736 men [53.0%]; median follow-up, 5.3 years [IQR, 3.4-7.4 years]), of whom 57 (4.1%) developed PSE. The 5-year cumulative risk of PSE was 3.7% (95% CI, 0.2%-4.8%) after ischemic stroke and 7.6% (95% CI, 3.5%-11.8%) after ICH. Factors associated with PSE after ischemic stroke were an acute symptomatic seizure (<7 days) (hazard ratio [HR], 10.83 [95% CI, 2.05-57.07]; P = .005) and cortical involvement (HR, 5.35 [95% CI, 1.85-15.49]; P = .002). The only factor associated with PSE after ICH was cortical involvement (HR, 8.20 [95% CI, 2.22-30.25]; P = .002). The C statistic was 0.78 (95% CI, 0.71-0.84) for the SeLECT 2.0 risk score and 0.83 (95% CI, 0.76-0.90) for the CAVE risk score, and calibration was good for both scores.

Conclusion

This study suggests that the risk of PSE among young adults is relatively low and that the factors that were associated with PSE were similar to variables included in the existing risk scores, which can therefore also be applied for young adults after stroke. Future clinical trials should investigate the optimal primary and secondary prophylaxis for patients at high risk.

Genome-wide association meta-analyses of drug-resistant epilepsy

BACKGROUND

Epilepsy is one of the most common neurological disorders, affecting over 50 million people worldwide. One-third of people with epilepsy do not respond to currently available anti-seizure medications, constituting one of the most important problems in epilepsy. Little is known about the molecular pathology of drug resistance in epilepsy, in particular, possible underlying genetic factors are largely unknown.

METHODS

We performed a genome-wide association study (GWAS) in two epilepsy cohorts of European ancestry, comparing drug-resistant (N = 4208) to drug-responsive individuals (N = 2618) followed by meta-analyses across the studies. Next, we performed subanalyses split into two broad subtypes: acquired or non-acquired focal and genetic generalized epilepsy.

FINDINGS

Our drug-resistant versus drug-responsive epilepsy GWAS meta-analysis showed no significant loci when combining all epilepsy types. Sub-analyses on individuals with focal epilepsy (FE) identified a significant locus on chromosome 1q42.11-q42.12 (lead SNP: rs35915186, P = 1·51 × 10-8, OR[C] = 0·74). This locus was not associated with any epilepsy subtype in the latest epilepsy GWAS (lowest uncorrected P = 0·009 for FE vs. healthy controls), and drug resistance in FE was not genetically correlated with susceptibility to FE itself. Seven genome-wide significant SNPs within this locus, encompassing the genes CNIH4, WDR26, and CNIH3, were identified to protect against drug-resistant FE. Further transcriptome-wide association studies (TWAS) imply significantly higher expression levels of CNIH3 and WDR26 in drug-resistant FE than in drug-responsive FE. CNIH3 is implicated in AMPA receptor assembly and function, while WDR26 haploinsufficiency is linked to intellectual disability and seizures. These findings suggest that CNIH3 and WDR26 may play a role in mediating drug response in focal epilepsy.

INTERPRETATION

We identified a contribution of common genetic variation to drug-resistant focal epilepsy. These findings provide insights into possible mechanisms underlying drug response variability in epilepsy, offering potential targets for personalised treatment approaches.

FUNDING

This work is part of the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement n° 279062 (EpiPGX) and the Centers for Common Disease Genomics (CCDG) program, funded by the National Human Genome Research Institute (NHGRI) and the National Heart, Lung, and Blood Institute (NHLBI).

Change of heart rate variability in children and adolescent with drug resistant epilepsy

Heart rate variability (HRV) has been examined and employed as a predictive biomarker for epilepsy. Patients with epilepsy exhibit reduced HRV as a result of heightened sympathetic activity. Reductions in HRV are observed in patients with sudden unexpected death in epilepsy (SUDEP). Our study aims to determine the change in HRV among children and adolescents with drug-resistant epilepsy (DRE) and advocate for its use as a biomarker to assess cardiovascular health in this population. Fifty-four children and adolescents, aged between 6 and 20 years, were enrolled and divided into two groups: the epilepsy group comprised 27 children diagnosed with DRE. Thirty minutes of HRV measurements were performed on both patients and controls. The median age was 12 years old. Malnutrition was the most common comorbidity in the epilepsy group. 75% have been diagnosed with DRE for more than 10 years. 44% had daily seizures. Generalized tonic-clonic seizures (GTCs) were the most common seizure type, accounting for 55.6% of cases. The most frequent cause of epilepsy was structural brain lesions (55.6%), followed by genetic disorders (18.5%). Patients with DRE had a significant reduction in both HRV's time domain (RMSSD and pNN50) and frequency domain (HF and LF). Patients who had GTC and had epilepsy for more than 10 years had a significant reduction in the low-frequency domain of HRV, according to the subgroup analysis. Children and adolescents with DRE exhibited a marked decrease in HRV measures, thereby increasing the likelihood of cardiovascular health issues in these patients. HRV can be used as a biomarker to effectively assess cardiovascular health in DRE patients.

Targeted therapies in epilepsies

In recent years, the increasing availability of antiseizure medications has not reduced the incidence of drug-resistant epilepsy. Precision medicine offers the potential for mechanism-driven treatments for rare pediatric epilepsies. The concept of precision medicine is not new in the field of epilepsy, as demonstrated by the use of pyridoxine for antiquitin deficiency (pyridoxine-dependent epilepsy) and the ketogenic diet for GLUT1 deficiency syndrome. More recently, preclinical evidence has led to phase 3 clinical trials, such as the use of everolimus to inhibit the mTOR pathway in tuberous sclerosis complex. However, preclinical findings do not always translate into effective treatments, as illustrated by the heterogeneous effects of quinidine in KCNT1-related epilepsy. Currently, an exponential increase in compounds identified at the preclinical level will require clinical trial validation. However, it remains uncertain whether these developments will lead to improved efficacy in drug-resistant epilepsy or have any disease-modifying effects. This article does not explicitly address antisense oligonucleotides or gene therapy.

Intracranial neuromodulation for pediatric drug-resistant epilepsy: early institutional experience

Introduction

Pediatric drug-resistant epilepsy (DRE) is defined as epilepsy that is not controlled by two or more appropriately chosen and dosed anti-seizure medications (ASMs). When alternative therapies or surgical intervention is not viable or efficacious, advanced options like deep brain stimulation (DBS) or responsive neurostimulation (RNS) may be considered.

Objective

Describe the Stanford early institutional experience with DBS and RNS in pediatric DRE patients.

Methods

Retrospective chart review of seizure characteristics, prior therapies, neurosurgical operative reports, and postoperative outcome data in pediatric DRE patients who underwent DBS or RNS placement.

Results

Nine patients had DBS at 16.0 ± 0.9 years and 8 had RNS at 15.3 ± 1.7 years (mean ± SE). DBS targets included the centromedian nucleus of the thalamus (78% of DBS patients), anterior nucleus of the thalamus (11%), and pulvinar (11%). RNS placement was guided by stereo-EEG and/or intracranial monitoring in all RNS patients (100%). RNS targets included specific seizure onset zones (63% of RNS patients), bilateral hippocampi (25%) and bilateral temporal lobes (12%). Only DBS patients had prior trials of ketogenic diet (56%) and VNS therapy (67%). Four DBS patients (44%) had prior neurosurgical interventions, including callosotomy (22%) and focal resection (11%). One RNS patient (13%) and one DBS patient (11%) required revision surgery. Two DBS patients (22%) developed postoperative complications. Three RNS patients (38%) underwent additional resections; one RNS patient had electrocorticography recordings for seizure mapping before surgery. For patients with a follow-up of at ≥1 year (n = 7 for DBS and n = 5 for RNS), all patients had reduced seizure burden. Clinical seizure freedom was achieved in 80% of RNS patients and 20% had a >90% reduction in seizure burden. The majority (71%) of DBS patients had a ≥50% reduction in seizures. No patients experienced no change or worsening of seizure frequency.

Conclusion

In the early Stanford experience, DBS was used as a palliatively for generalized or mixed DRE refractory to other resective or modulatory approaches. RNS was used for multifocal DRE with a clear seizure focus on stereo-EEG and no prior surgical interventions. Both modalities reduced seizure burden across all patients. RNS offers the additional benefit of providing data to guide future surgical planning.

Effects of the ketogenic diet on dentate gyrus and CA3 KCC2 expression in male rats with electrical amygdala kindling-induced seizures

Introduction

Ketogenic diet (KD), a high-fat, low-carbohydrate, and adequate protein diet, is a non-pharmacological treatment for refractory epilepsy. However, their mechanism of action is not fully understood. The cation-chloride cotransporter, KCC2, transports chloride out of neurons, thus contributing to the intraneuronal concentration of chloride. Modifications in KCC2 expression by KD feeding could explain the beneficial effect of this diet on epilepsy. This study aimed to determine the impact of KD on KCC2 expression in dentate gyrus layers and Cornu Ammonis 3 (CA3) strata of rats with seizures induced by amygdaloid kindling.

Materials and methods

Male Sprague Dawley rats were fed a normal diet (ND) or KD from postnatal day 24 until the end of the experiment. At 6 weeks after the start of the diets, rats were subjected to an amygdala kindling epilepsy model, sham or remain intact. Glucose and β-hydroxybutyrate concentrations were quantified. The after-discharge duration (ADD), latency, and duration of stages of kindling were evaluated. In addition, KCC2 expression was evaluated using optical density. A Pearson bivariate correlation was used to determine the relationship between KCC2 expression and ADD.

Results

At the end of the experiment, the KD-fed groups showed a reduction in glucose and an increase in β-hydroxybutyrate. KD reduced ADD and increased latency and duration of generalized seizures. In ND-fed animals, kindling reduced KCC2 expression in all three layers of the dentate gyrus; however, in KD-fed animals, no changes were observed. KD treatment increased KCC2 expression in the kindling group. In CA3, the pyramidal and lucidum strata showed an increase of KCC2 in KD-fed groups. Besides, the kindling had lower levels of KCC2 than the sham and intact groups. In all layers of the dentate gyrus and pyramidal and lucidum CA3 strata, the correlation indicated that the higher the KCC2 expression, the shorter the ADD during generalized seizures.

Conclusion

KD reduces ADD in generalized seizures. In addition, KD has a putative neuroprotective effect by preventing the kindling-induced reduction of KCC2 expression in the molecular, granule, and hilar dentate gyrus layers and pyramidal and lucidum CA3 strata. Increased KCC2 expression levels are related to a shorter duration of generalized seizures.

The response to anti-seizure medications and the development of pharmacoresistant epilepsy in malformations of cortical development

BACKGROUND

Malformations of cortical development (MCD) are a group of congenital brain malformation disorders commonly associated with pharmacoresistant epilepsy (PRE). While studies often focus on surgery outcomes, the pharmacological treatment is still imperative and the odyssey to PRE remains underexplored. We aim to investigate the influence of anti-seizure medications (ASMs) on the development of PRE in this specific patient population.

METHODS

We retrospectively included a cohort of epilepsy patients with MRI-confirmed MCD due to abnormal cell proliferation and apoptosis (group I, mainly FCD II), and abnormal neuronal migration (group II, mainly heterotopia, lissencephaly, and polymicrogyria) from March 2013 to June 2023. The clinical features of group I and group II were compared. Factors associated with PRE were analyzed. The time to development of PRE with different ASMs was assessed using Kaplan-Meier survival analysis.

RESULTS

Of 259 enrolled patients with epilepsy and MRI-confirmed MCD (group I, n = 121; group II, n = 138), 73.4% met the criteria for PRE. The median duration of follow-up from seizure onset to the last visit or surgery was 103 months (IQR 45-174), with group I showing a significantly higher PRE rate than group II (90.1% vs. 58.7%, p = 0.000). Binomial regression analysis identified the significant predictors of PRE in MCD patients: high pretreatment seizure frequency (OR = 2.506), group II patients (OR = 0.248), and failure of the first ASM (OR = 5.885). Sodium channel blockers (SCBs) were the most prescribed initial ASMs and demonstrated a higher response rate than other ASMs. Kaplan-Meier analysis revealed that using SCBs as the first ASM significantly prolongs the time to PRE, with a median of 72 months for SCB users versus 48 months for non-SCB users.

CONCLUSIONS

Our findings indicate a high prevalence of PRE that varies among different subtypes of MCD. Early appropriate selection of ASMs, particularly SCBs, can significantly delay the time to PRE onset, offering a promising strategy for managing this complex patient population. Tailoring pharmacological approaches is crucial for optimizing outcomes, and further research is warranted to optimize treatment strategies.

Genetic aetiologies in relation to response to the ketogenic diet in 226 children with epilepsy

A ketogenic diet is used in children with drug-resistant epilepsy but predictors for efficacy are largely lacking. Our aim was to evaluate if causative genetic variants could predict seizure response to the ketogenic diet. A cohort study of 226 children with refractory epilepsy and classic ketogenic diet treatment for at least 3 months (76.9% of the 294 who started) was performed. The median age at diet start was 5.1 years (range 0.1-17.8), 118 were girls and 108 boys. They had previous trials of a median of 6.0 anti-seizure medications (range 0-12) and intellectual disability was found in 87%. Seizure response (≥50% reduction) was found in 138/226 patients (61.1%) at 3 months, 121 (53.5%) at 6 months, 107 (47.3%) at 1 year and in 80 (37.0%) at 2 years follow-up of ketogenic diet. Age of epilepsy onset was lower and combined epilepsy type less common in responders compared to non-responders but no differences were found for specific seizure types, ketogenic ratio or beta-hydroxybutyric acid blood levels. A causative pathogenic/likely pathogenic variant was detected in 107/153 = 69.9% in 48 different genes. Next generation sequencing was used in 91/226 (40%) cases with a diagnostic yield of 58.2% (53/91). In comparison with cases without a revealed genetic aetiology, patients with a causative genetic variant had less atonic seizures and epileptic spasms and a better seizure response with 17.3% seizure free and 25% with >90% seizure reduction at 2-year follow-up. Causative variants in SLC2A1, SCN1A, STXBP1 and PAFAH1B1 showed significant diet response (P < 0.05) and good efficacy was also associated with DEPDC5, GLDC, KCNT1, PDHA1, SLC25A12 and TSC1. Causative variants in COL4A1 and DYNC1H1 were among genes linked to a lack of response. To our knowledge not described previously, we report a good ketogenic diet response related to causative variants in CSNK2A1, FARS2, GABRB3, GRIN1, KCNA2, KCTD3, STX1B and SLC16A2 but a lack of response for causative variants in CLN5, GLI3, MACF1, MAGEL2, NANS, NEMO/IKBKG, RORB, SLC17A5 and UFSP2. After grouping of genes into functional groups, causative variants in transporter genes had the best response (P = 0.009) and variants in other membrane-related proteins (ion channels and neurotransmitter receptors) also showed good efficacy. However, the gene group related to cell structural integrity and/or homeostasis had the worst diet response (P = 0.00006). In conclusion, our results support that causative genetic variants may be used as prognostic markers of ketogenic diet response, constituting an example in the expanding area of precision medicine.

Drug-resistant epilepsy in Saudi Arabia: prevalence, predictive factors, and treatment outcomes

BACKGROUND/OBJECTIVES

Drug-resistant epilepsy (DRE) is a significant global public health challenge affecting people with epilepsy (PWE). Despite the availability of multiple drug therapies, a significant number of PWE with DRE continue to experience frequent seizures. Current data on the prevalence of DRE and associated risk factors in the Saudi population is limited. This study aimed to estimate and characterize DRE among PWE and identify associated predictive factors.

MATERIALS AND METHODS

A cross-sectional study was conducted on PWE who attended Neurology clinics at the National Guard Health Affairs in Riyadh, Saudi Arabia (NGHA-R) between June 2016 and February 2023. Data were collected from patient medical records. Descriptive analyses of continuous and categorical variables were performed. Comparisons between categorical data were conducted using Pearson's chi-squared test. Multivariable logistic regression was used to identify independent factors associated with the development of DRE. A p-value of < 0.05 was considered statistically significant.

RESULTS

A total of 350 patients were analyzed, with a confirmed DRE prevalence of 26.86% (94 out of 350). Age-specific analysis revealed that DRE was most prevalent in the 29-39 age group, accounting for 35.1% (33 out of 94) of cases. The primary predictor for DRE was focal seizure type (AOR = 1.85; 95% CI: 1.05-3.27, p = 0.03). Additionally, DRE patients were more likely to visit the emergency room. Among antiseizure medications, treatment regimens of valproic acid (p = 0.0008), carbamazepine (p = 0.0097), and lamotrigine (p = 0.037) showed significant associations with DRE status.

CONCLUSION

The prevalence of DRE in Saudi Arabia remains within the previously reported range of global prevalence. Frequent emergency department visits and the use of ASM polytherapy should be followed up closely to ensure early diagnosis of DRE and improve clinical outcomes.

The association of SCN1A polymorphisms with epilepsy and drug resistance: a systematic review and meta-analysis

Epilepsy is one of the most common neurological afflictions worldwide, with one-third of patients exhibiting resistance to treatment. It has been speculated that the polymorphisms of the sodium channel alpha subunit 1 (SCN1A) gene are associated with both the occurrence of epilepsy and its resistance to treatment. The aim of this study is to systematically review the literature and conduct meta-analyses revealing the associations of the SCN1A polymorphisms with epilepsy and resistance to treatment. We conducted a search of Pubmed, Web of Science, and Scopus, and if more than two studies investigated a polymorphism, odds ratios for association with epilepsy and/or resistance to treatment were calculated in three allelic, homozygous, and recessive genetic models. The initial search yielded 4106 items, and a total of 64 articles met the final inclusion criteria. With respect to the occurrence of epilepsy, the rs2298771 polymorphism was revealed to be negatively associated in the recessive model, while the associations of other polymorphisms were not statistically significant. With regard to resistance to treatment, rs2298771 was revealed to be positively associated across all three models, and rs10167228 was positively associated in the allelic and homozygous models, but not the recessive model. Other polymorphisms were not shown to be associated with resistance to treatment. In conclusion, we demonstrated that the rs2298771 polymorphism had a significant and negative association with the occurrence of epilepsy. Furthermore, rs2298771 and rs10167228 polymorphisms had positive associations with resistance to treatment. Further studies are needed to explore these associations among other polymorphisms.

Genotype-phenotype correlation of ODLURO syndrome comorbid epilepsy associated with KMT2E variations: Report on a novel case and systematic literature review

BACKGROUND

O'Donnell-Luria-Rodan (ODLURO) syndrome is a newly described neurodevelopmental disorder caused by a pathogenic KMT2E variant. The primary clinical phenotypes include developmental delay, intellectual disability (ID), and epilepsy. Epilepsy, observed in 29% of affected individuals, has not been thoroughly investigated. In this study, we describe the phenotypes and genetic profiles of patients with ODLURO syndrome and epilepsy.

METHODS

We summarized and analyzed data from 30 patients with ODLURO syndrome and epilepsy from the systematic literature and DECIPHER database. Information regarding seizure classification, brain MRI findings, antiseizure medications, and genetics variations was collected and analyzed retrospectively.

RESULTS

The risk factors associated with epilepsy in ODLURO syndrome remain unclear, and clinical heterogeneity exists. While focal seizures are most prevalent, various epilepsy classifications are observed. Brain MRI findings indicated that cerebral atrophy and cystic changes were common, though no correlation with epilepsy was established. Among ten individuals with a record of antiseizure medication, approximately 70% required two or more antiseizure medications.

CONCLUSIONS

A clear genotype-phenotype correlation remains elusive even among individuals with the same KMT2E variation. The pathogenesis of epilepsy associated with KMT2E variation is complex and necessitates further molecular genetic studies to elucidate the mechanisms underlying these genetic disorders. This research provides essential evidence for specific and individualized treatment approaches.

The concept of difficult-to-treat disease in rheumatology: where next?

New pathogenesis-based therapeutics and evidence-based consensus treatment recommendations, often with predefined treatment goals, have remarkably improved outcomes across many chronic diseases. However, a clinically significant subgroup of patients responds poorly to interventions and show a progressive decline in the disease trajectory, which poses an increasing health-care challenge. Difficult-to-treat approaches exist in several areas of medicine and the need for similar definitions has recently also emerged in rheumatology. The term difficult-to-treat refers not only to patients with pathology-driven, treatment-refractory disease, but also implicates multiple other factors that can contribute to patients being in this state, including having few treatment options, misdiagnosis, and coincident psychosocial factors. Therefore, the difficult-to-treat state requires a comprehensive, holistic, multidisciplinary approach that considers the specific characteristics of each disease and the personalised needs of the patient. In this Personal View, we provide an overview of the different aspects of the concept of difficult-to-treat disease, highlight its advantages, and propose the importance of incorporating this concept more widely in the design of rheumatological treatment strategies.

Anticipatory guidance and care in pediatric and adult neurology for people with epilepsy who became pregnant

OBJECTIVE

To assess documentation of pregnancy-related counseling and care for people with epilepsy of childbearing potential (PWECP) in pediatric and adult neurology who became pregnant.

METHODS

We reviewed health records for primigravida PWECP prescribed an antiseizure medication (ASM) who delivered between June 2014 and May 2024 within one academic medical center. We used chi-squared tests to compare counseling, ASM prescriptions, and recommendations for supplemental folic acid between individuals in pediatric and adult neurology care before pregnancy. We performed logistic regression for these outcomes of pre-pregnancy counseling associated with type of neurology care, race, ethnicity, intellectual disability (ID), teratogenic profile of ASMs prescribed, and ASM polytherapy.

RESULTS

173 PWECP (84 % White non-Hispanic, 9 % with intellectual disability (ID) were included. Twenty-one (12 %) transferred from pediatric to adult neurology care due to pregnancy ("pediatric group") and 152 (88 %) were previously established with adult neurology ("adult group"). PWECP in the pediatric group compared to the adult group had lower rates of documentation of clinician discussion of ASM teratogenicity (43 % vs 66 %, p = 0.041) and folic acid use (24 % vs 63 %, p = 0.001) before pregnancy. PWECP established with adult neurology prior to pregnancy were significantly more likely to have been taking folic acid before pregnancy (OR 5.21, 95 % CI 1.78-15.3). Individuals with ID were significantly less likely to have documentation of discussion of ASM teratogenicity (OR 0.18, 95 % CI 0.05-0.62).

CONCLUSION

Our findings suggest a need for improvement in providing pre-pregnancy guidance and care for PWECP, especially for PWECP in pediatric neurology care and those with ID.

Which is the most cost-effective antiseizure medication for initial monotherapy for focal epilepsy?

OBJECTIVE

An increasing number of antiseizure medications (ASMs) are approved for monotherapy for focal epilepsy, but direct comparisons of the lifetime cost-effectiveness of all existing treatment strategies are lacking. This study aims to compare the cost-effectiveness of new ASMs and traditional ASMs as first-line monotherapy for newly diagnosed focal epilepsy.

METHOD

We used a Markov model to evaluate the lifetime cost-effectiveness of 10 ASMs in the treatment of focal epilepsy, with lacosamide (LCM) as a control, from the perspective of society in the United States. Effectiveness, cost data, and health state utilities were obtained from published literature. The cycle of the model is 6 months. Willingness to pay was defined as $150 000 per quality-adjusted life year (QALY). One-way and probabilistic sensitivity analyses were conducted to evaluate parameter uncertainty, and several scenario analyses were also conducted.

RESULTS

The base case analysis showed that carbamazepine (CBZ) was the least costly ASM and more effective than valproic acid (VPA), levetiracetam (LEV), gabapentin (GBP), topiramate (TPM), and lamotrigine (LTG) from an American social perspective. In contrast, oxcarbazepine (OXC), phenytoin (PHT), phenobarbitone (PHB), LCM, and zonisamide (ZNS) were more effective than CBZ, with incremental cost-effectiveness ratios of $334 703.50, $325 610.99, $3 037 148.62, $1 178 954.91, and $108 153 360.85/QALY, respectively. The traditional ASMs were ranked as CBZ, PHT, VPA, and PHB; the new ASMs were ranked as OXC, LEV, LCM, LTG, TPM, GBP, and ZNS. When generic drugs are used, PHT, OXC, and CBZ remain the three most cost-effective options.

SIGNIFICANCE

In terms of cost-effectiveness, CBZ monotherapy is the best option for newly diagnosed focal epilepsy, followed by OXC, PHT, VPA, LEV, PHB, LCM, LTG, TPM, GBP, and ZNS. Most traditional ASMs are more cost-effective than new ASMs; OXC is an exception.

Population pharmacokinetics of cannabidiol and the impact of food and formulation on systemic exposure in children with drug-resistant developmental and epileptic encephalopathies

OBJECTIVE

Identifying factors influencing cannabidiol (CBD) exposure can optimize treatment efficacy and safety. We aimed to describe the population pharmacokinetics of CBD in children with drug-resistant developmental and epileptic encephalopathies (DEEs) and assess the influence of environmental, pharmacological, and clinical characteristics on CBD systemic exposure.

METHODS

Data from two pharmacokinetic studies of patients aged 2-18 years with DEEs were included (N = 48 patients). Serial blood samples were collected during maintenance treatment, before and after the morning dose, and up to 6 h after a dose of a purified CBD oil formulation, with or without a normocaloric breakfast. CBD plasma concentrations were also available following administration of a CBD-enriched formulation. Samples were quantified using a validated liquid chromatography/tandem mass spectrometry assay. A CBD population pharmacokinetic model was developed using nonlinear mixed-effects modeling. The effects of formulation, concomitant food intake, and demographic, clinical, and pharmacological factors on CBD pharmacokinetics were evaluated. Simulated maximum plasma concentration (Cmax) and area under the concentration-time curve between 0 and 12 h (AUC0-12) were calculated.

RESULTS

A one-compartment model with transit compartments and first-order elimination best described CBD pharmacokinetics. Mean values for CBD apparent clearance (CL/F) and volume of distribution (V/F) were 143.5 L/h and 1892.4 L, respectively. Weight was allometrically scaled for V/F and CL/F, sex was associated with V/F, and both formulation and food condition were associated with F (relative bioavailability). CBD Cmax increased by 41% and AUC0-12 by 45% when CBD was administered with food compared to fasting. Dose-normalized AUC0-12 was approximately 50% lower with CBD-enriched oil compared to purified CBD.

SIGNIFICANCE

In the present study, we described the effects of food and formulation on CBD exposure in children with DEEs. Increased CBD exposure with food intake and significant changes in drug exposure when switching between CBD formulations should be considered in patient management.

Focal to bilateral tonic-clonic seizures in newly diagnosed focal epilepsy

Presence of focal to bilateral tonic-clonic seizures (FBTCS) in focal epilepsy is associated with increased morbidity and mortality. Risk factors for FBTCS are poorly understood, and little is known regarding FBTCS recurrence after treatment initiation. This study aimed to investigate factors related to FBTCS in newly diagnosed focal epilepsy and their recurrence after starting antiseizure medications (ASMs) in the Human Epilepsy Project (HEP) cohort. HEP was an international, prospective cohort study that enrolled people with newly diagnosed focal epilepsy within 4 months of treatment initiation and followed them for up to 6 years. Baseline characteristics, treatment choices, and seizure outcomes were collected. Descriptive and inferential statistical analysis was conducted to assess the differences between study participants who had FBTCS and those who never experienced FBTCS. A total of 443 participants were included in this analysis; 77% (n = 342) had FBTCS at some point prior to or within the study period. In participants with FBTCS, regardless of initial seizure type, diagnosis was mostly made after FBTCS (335/342, 98%). After treatment initiation, FBTCS did not recur in 57% (n = 194/342) of cases. A higher number of total pretreatment seizures (median = 16 vs. 11, p = .048, Mann-Whitney U-test), predominantly focal aware seizures (FAS) or focal impaired awareness seizures (FIAS; median = 15 vs. 10, p = .049, Mann Whitney U-test), was associated with no recurrence in FBTCS after treatment initiation. Of 108 participants without FBTCS prior to treatment, only seven (6%) developed FBTCS after treatment initiation. There was no significant difference in choice of initial ASM class (levetiracetam vs. sodium channel blockers) between participants who experienced FBTCS and those who did not. This study highlights the significance of FBTCS among individuals with newly diagnosed focal epilepsy. The majority of participants who experienced FBTCS were diagnosed with epilepsy after experiencing their first FBTCS despite preceding FAS/FIAS. The more frequent FAS/FIAS in participants whose FBTCS resolved may be a characteristic of their epilepsy.

Epilepsy Surgery for Drug-Resistant Epilepsy in Africa: A Systematic Review

BACKGROUND AND OBJECTIVES

Nearly one-third of individuals with epilepsy have drug-resistant epilepsy, treated most effectively with surgery. This study aims to discuss the demographic profile, surgical access, and strategies used in drug-resistant epilepsy in Africa.

METHODS

A systematic review was performed using PubMed, Google Scholar, Embase, and Web of Science in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines.

RESULTS

Nine studies encompassing 498 patients from 6 African countries (Egypt, Kenya, Morocco, South Africa, Tunisia, and Uganda) were included. The mean Methodological Index for Non-Randomized Studies score for these articles was 9.6 ± 1.6. The average patient age was 24.9 years (95% CI: 18.9-30.8 years), with a male predominance of 53.4%. The average age of seizure onset was 10.4 years (95% CI: 6.1-14.7 years). Most patients experienced focal onset seizures (73.1%), with head trauma (33.1%) being the most reported risk factor. The predominant etiologies were hippocampal sclerosis (66.8%, 95% CI: 42.7-91), microdysgenesis (26.7%, 95% CI: 20.7-32.7), and brain tumors (22.3%, 95% CI: 6.4-38.2). Lesions were primarily located in the left hemisphere (61.9%, 95% CI: 26.7-97.1), with temporal lobe involvement in 54.8% of cases (95% CI: 28.7-80.8). Temporal lobectomy was the most frequently performed surgery (59.6%), followed by lesionectomy (9.6%). Postoperatively, 80.6% of patients achieved Engel class I outcomes, indicating seizure freedom, and long-term follow-up (1 to 5 years) showed that 70.3% maintained Engel class I outcomes. Surgical complications were reported in 8.8% of cases.

CONCLUSION

These findings demonstrate the efficacy and long-term benefits of epilepsy surgery in Africa, where epilepsy is a significant public health challenge. The high rates of seizure freedom and reduced seizure frequency from surgery highlight its potential to improve the quality of life for individuals with drug-resistant epilepsy in Africa.

Quantitative EEG biomarkers of cognitive performance in drug-resistant temporal lobe epilepsy

BACKGROUND

This study aimed to explore quantitative electroencephalography (qEEG) biomarkers of cognitive performance in drug-resistant temporal lobe epilepsy (TLE) and analyze their relationship with clinical characteristics.

METHODS

Cross-sectional study including adult patients with drug-resistant TLE and a control group. Resting-state, eyes-closed qEEG samples were analyzed using the fast Fourier transform approach. Power spectral density was calculated for four frequency bands: delta (1-3.9 Hz), theta (4-7.9 Hz), alpha (8-12.9 Hz), and beta (13-18 Hz). Neuropsychological tests were administered to TLE patients.

RESULTS

Twenty-nine TLE patients (mean age 42 ± 8.2 years; 44.8 % women) and 23 age- and sex-matched controls were enrolled. Clinically significant cognitive impairment was found in 86.2 % of patients (58.6 % amnestic). Compared to controls, TLE patients showed increased ipsilateral power spectral density for the theta (p = 0.045), alpha (p = 0.023) and beta bands in the anterior region (p = 0.029) and for the delta band in the posterior region (p = 0.03). Alpha/theta ratio (ATR) was lower in the posterior quadrant of the epileptogenic hemisphere (p = 0.013), and higher seizure frequency correlated with a lower ATR in the ipsilateral temporal region (r: -0.425; p = 0.021). Patients with amnestic cognitive impairment exhibited higher power spectral density across most frequency bands (p < 0.005). Impaired verbal memory and executive function were associated with increased power density.

CONCLUSION

Increased power spectral density was evident in all frequency bands in the epileptogenic hemisphere, particularly in those patients with amnestic cognitive impairment. Moreover, higher seizure frequency correlated with a lower ATR in the temporal region. Power spectral analysis can provide useful information in drug-resistant TLE patients.

Enhancing epilepsy care in Argentina: Use of SEEG in a developing setting

OBJECTIVES

The aim of this study is to describe a population of patients with drug resistant epilepsy who underwent stereoelectroencephalography (SEEG) for epilepsy presurgical evaluation in a high complexity public hospital in Argentina.

METHODS

We included patients from 2014 to 2023. We conducted a retrospective study of patients with drug-resistant epilepsy admitted to the Video-EEG unit. We selected patients who underwent SEEG and analyzed those patients in whom surgery was performed. The variables studied were MRI findings, epileptogenic zone (EZ) location, type of surgery performed, neuropsychological evaluation, post-surgical evolution and histopathology.

RESULTS

In the study period, 49 patients underwent SEEG. Magnetic resonance imaging (MRI) was normal in 21/49 (43 %). Eighteen patients (37.5 %) had bilateral implantation, 16 (32.7 %) had unilateral right hemisphere implantation and 15 (31.3 %) unilateral left sided implantation. Surgical treatment was indicated in 30 (61,2 %) patients. Post-surgery outcome according to the International League Against Epilepsy (ILAE) classification, was ILAE I 26.6 % and ILAE II 30 %.

CONCLUSION

Our experience highlights that, with proper training and resource allocation, high-quality epilepsy care, including advanced diagnostic procedures like SEEG, is achievable in Argentina and may be possible in other developing regions.

Cost-effectiveness of clobazam as an adjunctive treatment for refractory epilepsy in China

BACKGROUND

Clobazam (CLB) is an effective, safe and well-tolerated adjunctive treatment for refractory epilepsy. However, the cost-effectiveness of CLB in China remains unclear.

AIM

The aim of this study was to evaluate the cost-effectiveness of CLB as an adjunctive therapy for patients with refractory epilepsy in China.

METHOD

A Markov model was established to simulate the lifetime epilepsy process in patients. The epilepsy remission rate, health state utility and mortality data were derived from clinical trials and the literature. The costs were collected from the health care system in the hospital. The primary outcome was the incremental cost-effectiveness ratio (ICER), which was calculated by comparing CLB as an add-on therapy with conventional therapy and was assessed in the context of the Chinese health system. One-way and probabilistic sensitivity analyses were conducted to evaluate parameter uncertainty, and several scenario analyses were also conducted.

RESULTS

Compared with maintaining conventional therapy, adding CLB as an adjuvant therapy increased the cost of Chinese Yuan (CNY) 1770.17 over a lifetime, with an incremental quality-adjusted life years (QALYs) value of 1.02, resulting in an ICER of CNY 1737.10 per QALY gained. The daily dose of CLB had the strongest effect on the ICER. The probabilistic sensitivity analyses revealed that the probability of CLB being cost-effective was 77.35% at a willingness to pay (WTP) of CNY 85698/QALY.

CONCLUSION

CLB is a cost-effective add-on therapy for refractory epilepsy in the Chinese population.