The epidemiology of drug-resistant epilepsy: A systematic review and meta-analysis

Seizure burden and healthcare resource utilization among people living with drug-resistant focal epilepsy in the United States

OBJECTIVE

This study investigated clinical characteristics, burden of uncontrolled seizures, and seizure-related healthcare resource utilization (HRU) among individuals living with drug-resistant focal epilepsy (FE) in the United States (US).

METHODS

Medical charts of adults with drug-resistant FE who initiated third-line (3 L) anti-seizure medication were extracted from clinical practices in the US (1/1/2013-1/31/2020). The index date, defined as the date of 3 L initiation, was used to indicate the emergence of drug resistance. Individuals on cenobamate were followed for any length of time from the index date. Demographic and clinical characteristics were analyzed descriptively. Primary clinical outcomes included seizure burden (i.e. change in seizure frequency and time to the first and second seizure events) and epilepsy-related HRU.

RESULTS

Overall, 189 neurologists/epileptologists contributed 345 charts of individuals living with drug-resistant FE (66% male; average age 24 years at diagnosis and 32 years at index date). 66% had ≥1 neurologic/neuropsychiatric comorbidity at baseline. Average monthly seizure rate decreased from 6.1 at baseline to 3.8 at follow-up; however, nearly half of individuals experienced worse/no change or only some improvement (<50% reduction) in seizure frequency. Most individuals (91%) had ≥1 epilepsy-related outpatient visit during follow-up. Unplanned HRU included emergency department visits (43%) and hospitalizations (24%), primarily due to breakthrough seizure events.

CONCLUSION

Despite the availability of many anti-seizure medications in the US, people living with drug-resistant FE continue to experience multiple seizures per month and incur substantial healthcare resources. Novel pharmacotherapies may help individuals living with drug-resistant epilepsy achieve seizure freedom.

The course of tumor-related epilepsy in glioblastoma patients: A retrospective analysis

PURPOSE

Many patients with glioblastoma suffer from tumor-related seizures. However, there is limited data on the characteristics of tumor-related epilepsy achieving seizure freedom. The aim of this study was to characterize the course of epilepsy in patients with glioblastoma and the factors that influence it.

METHODS

We retrospectively analyzed the medical records of glioblastoma patients treated at the University Hospital Erlangen between 01/2006 and 01/2020.

RESULTS

In the final cohort of patients with glioblastoma (n = 520), 292 patients (56.2 %) suffered from tumor-related epilepsy (persons with epilepsy, PWE). Levetiracetam was the most commonly used first-line antiseizure medication (n = 245, 83.9 % of PWE). The onset of epilepsy was preoperative in 154/292 patients (52.7 %). 136 PWE (46.6 %) experienced only one single seizure while 27/292 PWE (9.2 %) developed drug-resistant epilepsy. Status epilepticus occurred in 48/292 patients (16.4 %). Early postoperative onset (within 30 days of surgery) of epilepsy and total gross resection (compared with debulking) were independently associated with a lower risk of further seizures. We did not detect dose-dependent pro- or antiseizure effects of radiochemotherapy.

CONCLUSION

Tumor-related epilepsy occurred in more than 50% of our cohort, but drug-resistant epilepsy developed in less than 10% of cases. Epilepsy usually started before tumor surgery.

Impact of epilepsy surgery on developmental trajectories of children under 3 years of age

AIM

To investigate the developmental effects of epilepsy surgery in young children.

METHOD

This study retrospectively reviewed 315 consecutive children under 3 years of age, and ultimately included 89 children (48 males, 41 females) with pre- and postsurgery developmental evaluations.

RESULTS

The mean general quotient before surgery was 46.7 (SD 24.7). Before surgery, the general quotient decreased in 77.6% of patients, while after surgery it increased in 55.1%. Furthermore, 70% of those 20 patients whose presurgical general quotient decreased by more than 10 points experienced positive changes. General quotient scores decreased in 15 out of the 22 patients classified in the normal/marginal presurgical category. Children who underwent surgery before the age of 12 months had a median gain in general quotient score by 7.6. Short-term general quotient scores were highly correlated with long-term scores (r = 0.909, p < 0.001).

INTERPRETATION

Surgical intervention was more inclined to positively impact developmental trajectories within a short postsurgical period, particularly among those affected by severe epileptic activity. However, in children with relatively typical development, certain developmental setbacks may arise. Postsurgical short-term developmental outcomes could predict longer-term outcomes.

Enhancing quality of life in epilepsy with a digital intervention (emyna): Results of the ELAINE randomized controlled trial

OBJECTIVE

Despite the availability of pharmacological treatment for seizures, people with epilepsy (PwE) commonly experience impairments in quality of life (QoL). Given the limited access to psychosocial treatments for PwE, digital interventions could bridge treatment gaps and help improve QoL. The objective of this study was to examine the effectiveness of emyna, a fully automated digital intervention based on cognitive behavioral therapy (CBT) techniques, in improving health-related QoL among PwE who reported impairments in QoL. A previous trial showed that emyna was effective in improving depressive symptoms among PwE with a comorbid depressive disorder, but its effects on QoL among PwE without comorbid depression remain unknown.

METHODS

A pragmatic randomized controlled trial was conducted with N = 438 PwE (mean age = 37.5, 70.3% women, physician-verified diagnoses) who were assigned to the intervention group (n = 216), which used emyna alongside treatment as usual (TAU), or the control group (n = 222), which received TAU only. QoL and secondary outcomes such as general self-efficacy, medication adherence, general distress, and epilepsy-related work and social adjustment were assessed at baseline, 3 months, and 6 months. The primary outcome was QoL assessed with the Quality of Life in Epilepsy [QOLIE-31] total score at 3 months post-randomization.

RESULTS

Findings from the intent-to-treat analyses showed that after 3 months, participants in the intervention group experienced significant and clinically relevant improvements in health-related QoL compared to the control group (baseline-adjusted group difference = 4.5; 95% CI = [2.0, 6.9], p < 0.001; Cohen's d = 0.32). Effects on secondary outcomes did not reach statistical significance.

SIGNIFICANCE

This study extends previous research by demonstrating that emyna facilitates improvements in QoL in a diverse group of PwE treated in routine care settings. This CBT-based digital intervention therefore presents a convenient and cost-effective addition to healthcare providers' treatment repertoire.

PLAIN LANGUAGE SUMMARY

In our study, we tested a digital program called emyna, which conveys cognitive behavioral therapy (CBT) techniques to help improve the quality of life for people living with epilepsy. We found that those who used emyna alongside their usual treatments felt better about their quality of life compared to those who did not use the program. Emyna offers a new, convenient way for people with epilepsy to manage their condition, which can be used alongside currently available treatments.

Trends in Prevalence and Incidence of Epilepsy and Drug-Resistant Epilepsy in Children: A Nationwide Population-Based Study in Korea

Population-based data on drug-resistant epilepsy (DRE) are lacking. This retrospective study aimed to determine the prevalence and incidence of pediatric epilepsy and DRE in South Korea using health insurance claims data from the Health Insurance Review and Assessment Service (2013-2022). Epilepsy and DRE prevalence and incidence in children <18 years old were estimated over time and by age and sex. Results showed that the age-standardized prevalence and incidence rates of epilepsy increased. The age-standardized prevalence rate of DRE increased, while the age-standardized incidence rate remained unchanged. The standardized prevalence rate of DRE was 0.26 per 1000 persons, and the average standardized incidence rate of DRE was 0.06 per 1000 persons. The prevalence rate of DRE gradually increased with age, with age 0 demonstrating the highest incidence rate. The prevalence of generalized DRE was the highest across all ages, and incidence was the highest at 0 years. Conversely, the incidence of focal DRE did not change with age. Our study revealed a stable incidence rate of DRE in Korea, despite increased prevalence. DRE incidence was the highest in the first year of life, with the generalized type being the most prevalent.

Maintenance of response to ketogenic diet therapy for drug-resistant epilepsy post diet discontinuation: A multi-centre case note review

PURPOSE

There is limited research on the proportion of individuals with epilepsy who maintain response to ketogenic diet therapy (KDT) after discontinuing treatment. We aimed to determine the proportion of individuals who did / did not maintain response post KDT and explore factors that may influence the likelihood of maintaining response.

METHODS

Retrospective data were collected from 97 individuals from 9 KDT centres. Individuals had achieved ≥50 % seizure reduction on KDT for at least 12 months, with seizure frequency data available at 3 months+ post diet. Outcome 1 was: recurrence of seizures or increase in seizure frequency post diet; outcome 2: recurrence of seizures, increase in seizure frequency or an additional anti-seizure treatment started post diet.

RESULTS

61/97 (62.9 %) individuals maintained response at latest follow-up (mean 2.5[2.0] years since stopping KDT). Approximately one third maintained response without further anti-seizure treatments. One quarter of individuals had an increase in frequency or recurrence of seizures within 6 months (95 %CI 4, 12) for outcome 1 and within 3 months (3, 6) for outcome 2. Individuals who did not achieve seizure freedom on diet were significantly more likely to have an increase in seizures or to require additional anti-seizure treatments post diet compared to those who were seizure-free on diet (hazard ratio 4.02, 95 %CI (1.46, 11.16) p < 0.01).

CONCLUSION

Our findings should help guide clinical teams with the information they provide patients and their families regarding likelihood of long-term seizure response to KDT. Realistic costings for KDT services may need to be considered.

Neurocardiac pathologies associated with potassium channelopathies

Voltage-gated potassium channels are expressed throughout the human body and are essential for physiological functions. These include delayed rectifiers, A-type channels, outward rectifiers, and inward rectifiers. They impact electrical function in the heart (repolarization) and brain (repolarization and stabilization of the resting membrane potential). KCNQx and KCNHx encode Kv7.x and Kv11.x proteins, which form delayed rectifier potassium channels. KCNQx and KCNHx channelopathies are associated with both cardiac and neuronal pathologies. These include electrocardiographic abnormalities, cardiac arrhythmias, sudden cardiac death (SCD), epileptiform discharges, seizures, bipolar disorder, and sudden unexpected death in epilepsy (SUDEP). Due to the ubiquitous expression of KCNQx and KCNHx channels, abnormalities in their function can be particularly harmful, increasing the risk of sudden death. For example, KCNH2 variants have a dual role in both cardiac and neuronal pathologies, whereas KCNQ2 and KCNQ3 variants are associated with severe and refractory epilepsy. Recurrent and uncontrolled seizures lead to secondary abnormalities, which include autonomics, cardiac electrical function, respiratory drive, and neuronal electrical activity. Even with a wide array of anti-seizure therapies available on the market, one-third of the more than 70 million people worldwide with epilepsy have uncontrolled seizures (i.e., intractable/drug-resistant epilepsy), which negatively impact neurodevelopment and quality of life. To capture the current state of the field, this review examines KCNQx and KCNHx expression patterns and electrical function in the brain and heart. In addition, it discusses several KCNQx and KCNHx variants that have been clinically and electrophysiologically characterized. Because these channel variants are associated with multi-system pathologies, such as epileptogenesis, Kv7 channel modulators provide a potential anti-seizure therapy, particularly for people with intractable epilepsy. Ultimately an increased understanding of the role of Kv channels throughout the body will fuel the development of innovative, safe, and effective therapies for people at a high risk of sudden death (SCD and SUDEP).

Drug-resistant epilepsy in Morocco: description, prevalence and predictive factors in Casablanca-Settat region

Drug-resistant epilepsy (DRE) affects about one-third of people with epilepsy (PWE). Our study aims to estimate the DRE prevalence and its predictive factors in Morocco. A cross-sectional study was conducted over 18 months. PWE with clinical diagnosis of epilepsy, and with an antiseizure treatment duration >12 months were examined in the neurology, neurosurgery, psychiatry, and pediatrics departments, of different sampled clinical sectors for the Casablanca-Settat region. Sociodemographic and clinical data were collected using a questionnaire during consultations. Antiseizure multi-therapy, a seizure freedom duration <12 months, compliance, and adequate posology were the determining factors for classifying DRE. Data were analyzed using Statistical Package for Social Sciences (SPSS) software, version 21.0. Statistical significance was set at p < 0.05 and logistic regression was performed to determine the predictive factors. In our sample of 446 PWE, the median age is 25 years (IQR: 11.75-44.00). The DRE estimated prevalence was 29.4 %. Pseudo-resistant epilepsy (PRE) was 18.0 %. Multivariate logistic regression analysis reports that single marital status (ORa = 1.94; CI95%: 1.02-3.71), comorbidities and concomitant affections (ORa = 2.14; CI95%: 1.27-3.59), structural etiology (ORa = 1.96; CI95%: 1.16-3.30), pre-ictal aura (ORa = 1.90; CI95%: 1.09-3.29), inter-ictal EEG abnormalities (ORa = 2.45; CI95%: 1.24-4.84) and allopathic treatment use (ORa = 2.10; CI95%: 1.30-3.39) are the predictive factors for DRE. We report an alarming DRE prevalence. Associated factors found may contribute to the prognosis and early management. PWE awareness, facilitating healthcare access and the development of epilepsy surgery are the key points to limit DRE in Morocco and prevent its various complications, especially for the pediatric population.

Preclinical efficacy profiles of the sigma-1 modulator E1R and of fenfluramine in two chronic mouse epilepsy models

OBJECTIVE

Given its key homeostatic role affecting mitochondria, ionotropic and metabotropic receptors, and voltage-gated ion channels, sigma-1 receptor (Sig1R) represents an interesting target for epilepsy management. Antiseizure effects of the positive allosteric modulator E1R have already been reported in acute seizure models. Although modulation of serotonergic neurotransmission is considered the main mechanism of action of fenfluramine, its interaction with Sig1R may be of additional relevance.

METHODS

To further explore the potential of Sig1R as a target, we assessed the efficacy and tolerability of E1R and fenfluramine in two chronic mouse models, including an amygdala kindling paradigm and the intrahippocampal kainate model. The relative contribution of the interaction with Sig1R was analyzed using combination experiments with the Sig1R antagonist NE-100.

RESULTS

Whereas E1R exerted pronounced dose-dependent antiseizure effects at well-tolerated doses in fully kindled mice, only limited effects were observed in response to fenfluramine, without a clear dose dependency. In the intrahippocampal kainate model, E1R failed to influence electrographic seizure activity. In contrast, fenfluramine significantly reduced the frequency of electrographic seizure events and their cumulative duration. Pretreatment with NE-100 reduced the effects of E1R and fenfluramine in the kindling model. Surprisingly, pre-exposure to NE-100 in the intrahippocampal kainate model rather enhanced and prolonged fenfluramine's antiseizure effects.

SIGNIFICANCE

In conclusion, the kindling data further support Sig1R as an interesting target for novel antiseizure medications. However, it is necessary to further explore the preclinical profile of E1R in chronic epilepsy models with spontaneous seizures. Despite the rather limited effects in the kindling paradigm, the findings from the intrahippocampal kainate model suggest that it is of interest to further assess a possible broad-spectrum potential of fenfluramine.

Intraparenchymal delivery of adeno-associated virus vectors for the gene therapy of neurological diseases

INTRODUCTION

In gene therapy with adeno-associated virus (AAV) vectors for diseases of the central nervous system, the vectors can be administered into blood vessels, cerebrospinal fluid space, or the brain parenchyma. When gene transfer to a large area of the brain is required, the first two methods are used, but for diseases in which local gene transfer is expected to be effective, vectors are administered directly into the brain parenchyma.

AREAS COVERED

Strategies for intraparenchymal vector delivery in gene therapy for Parkinson's disease, aromatic l-amino acid decarboxylase (AADC) deficiency, and epilepsy are reviewed.

EXPERT OPINION

Stereotactic intraparenchymal injection of AAV vectors allows precise gene delivery to the target site. Although more surgically invasive than intravascular or intrathecal administration, intraparenchymal vector delivery has the advantage of a lower vector dose, and preexisting neutralizing antibodies have little effect on the transduction efficacy. This approach improves motor function in AADC deficiency and led to regulatory approval of an AAV vector for the disease in the EU. Although further validation through clinical studies is needed, direct infusion of viral vectors into the brain parenchyma is expected to be a novel treatment for Parkinson's disease and drug-resistant epilepsy.

Real-world anti-seizure treatment and adverse events among individuals living with drug-resistant focal epilepsy in the United States

OBJECTIVE

This study aimed to understand how people living with drug-resistant focal epilepsy (DRE) navigate through lines of antiseizure medications (ASM) and experience adverse events (AEs) in the real-world setting in the United States.

METHODS

A retrospective study was conducted with medical chart data from clinical practices in the United States. Eligible adults had a confirmed diagnosis of DRE and initiated a third-line ASM therapy between January 2013 and January 2020 (i.e., the index date). Subjects must have medical history data available for ≥1 year prior to (the baseline) and ≥2 years after the index date (the follow-up). Treatment patterns were captured from first to fourth lines. After the emergence of drug resistance, time to ASM discontinuation, reasons for discontinuation, AE experience and AE management were reported separately during third and fourth lines of treatment and beyond.

RESULTS

The study included a total of 345 individuals, with an average (standard deviation) age of 23.9 (11.9) years at first diagnosis. All individuals had at least three lines of ASMs with first and second lines during baseline, and third line during follow-up. The first line for most individuals was monotherapy. As individuals progressed through additional lines of ASM therapy, they were more likely to receive polytherapy. The regimens were more individualized after meeting drug resistance criteria. The top reasons for discontinuing were uncontrolled seizure and/or intolerance/AEs for both third and subsequent lines. More than a third of individuals experienced at least one AE. Among those with at least one AE, many individuals had to manage these AEs with dose adjustment (39.4%), discontinuation of offending ASM (37.9%), de novo pharmacotherapy (25.8%), emergency room visit (13.6%), and hospitalization (12.1%).

SIGNIFICANCE

This study demonstrated that individuals living with DRE experience significant AEs, and many of these AEs lead to treatment disruption and significant healthcare resource utilization.

PLAIN LANGUAGE SUMMARY

This study examined how individuals with focal epilepsy are treated across various clinics in United States and reported the adverse events these individuals experienced during treatment, along with the consequence associated with these adverse events. We found that as individuals progressed through additional treatments, they were more and more likely to receive more than one antiseizure medication, and a significant portion of individuals experienced at least one adverse event, often manifested as headache, somnolence, dizziness, and fatigue.

Tolerability of tariquidar - A third generation P-gp inhibitor as add-on medication to antiseizure medications in drug-resistant epilepsy

PURPOSE

P-glycoprotein (P-gp) has been hypothesized to be involved in drug-resistance of epilepsy by actively extruding antiseizure medications (ASMs) from the brain. The P-gp inhibitor tariquidar (TQD) has been shown to effectively inhibit P-gp at the human blood-brain barrier, improving brain entry of several ASMs. A potential strategy to overcome drug-resistance is the co-administration of P-gp inhibitors such as TQD to ASMs. Here we present data on the tolerability of single-dose TQD as a potential add-on medication to ASMs.

METHODS

We performed a multi-centre cohort study including drug-resistant epilepsy patients and healthy controls from the United Kingdom and Austria. TQD was administered intravenously at five different doses (2 mg/kg or 3 mg/kg of TQD were given to drug-resistant epilepsy patients and healthy controls, higher doses of TQD at 4 mg/kg, 6 mg/kg and 8 mg/kg as well as a prolonged infusion aiming at a dose of 6 mg/kg were only given to healthy controls). Adverse events were recorded and graded using the Common Terminology Criteria (CTCAE) scale. Additionally, TQD plasma concentration levels were measured and compared between drug-resistant patients and healthy controls.

RESULTS

In total, 108 participants received TQD once at variable doses and it was overall well tolerated. At doses of 2 or 3 mg/kg TQD, only two of the 19 drug-resistant epilepsy patients and a third of the healthy controls (n = 14/42) reported adverse events probably related to TQD. The majority of those adverse events (96 %) were reported as mild. One drug-resistant epilepsy patient reported adverse events 24-hours after TQD administration possibly related to TQD-induced increased ASMs levels in the brain.

CONCLUSIONS

TQD is an effective and well tolerated P-gp inhibitor as a single dose and could potentially be used intermittently in conjunction with ASMs to improve efficacy. This promising strategy to overcome drug-resistance in epilepsy should be investigated further in clinical randomised controlled trials.

Clinical utility of Epitrack for differentiating profiles and patterns of post-surgical change in memory and quality of life in patients with drug-resistant epilepsy

PURPOSE

To assess whether performance in attention and executive functions evaluated with the Epitrack screening tool before surgery can differentiate memory and quality of life (QOL) profiles, and detect different post-surgical change patterns in these variables in patients with epilepsy.

METHODS

This is a longitudinal study. Seventy-seven patients with drug-resistant epilepsy (mean age = 37.91) underwent a neuropsychological assessment before and one year after surgery. Epitrack, a screening tool that exclusively evaluates attention and executive functioning, was administered in the pre-surgical assessment, and verbal and visual memory and QOL were assessed before and after surgery.

RESULTS

Patients with impaired Epitrack performance had poorer verbal and visual memory than those with intact Epitrack performance, regardless of the time point (for all, p < 0.0001). They also showed a post-surgical decline in immediate verbal recall (p = 0.04) and discriminability (p = 0.001). Patients with intact Epitrack performance did not exhibit this decline. Epitrack total score significantly contributed to 13 and 11% of the variance of post-surgical changes in immediate verbal recall and discriminability, respectively. Epitrack groups did not differ in QOL profiles or changes, but post-surgical immediate verbal recall improvements were related to post-surgical QOL improvements.

CONCLUSION

Our findings underline the utility of Epitrack screening tool to detect different patterns of verbal and visual memory dysfunction, as well as to predict post-surgical verbal memory decline in patients with drug-resistant epilepsy. Patients with lower pre-surgical Epitrack scores appear to be at increased risk for post-surgical memory decline.

Current role of magnetic resonance imaging on assessing and monitoring the efficacy of phototherapy

Phototherapy, also known as photobiological therapy, is a non-invasive and highly effective physical treatment method. Its broad use in clinics has led to significant therapeutic results. Phototherapy parameters, such as intensity, wavelength, and duration, can be adjusted to create specific therapeutic effects for various medical conditions. Meanwhile, Magnetic Resonance Imaging (MRI), with its diverse imaging sequences and excellent soft-tissue contrast, provides a valuable tool to understand the therapeutic effects and mechanisms of phototherapy. This review explores the clinical applications of commonly used phototherapy techniques, gives a brief overview of how phototherapy impacts different diseases, and examines MRI's role in various phototherapeutic scenarios. We argue that MRI is crucial for precise targeting, treatment monitoring, and prognosis assessment in phototherapy. Future research and applications will focus on personalized diagnosis and monitoring of phototherapy, expanding its applications in treatment and exploring multimodal imaging technology to enhance diagnostic and therapeutic precision and effectiveness.

Association of outdoor air and noise pollution with unprovoked seizures and new onset epilepsy: A systematic review and meta-analysis

Research has indicated that certain environmental exposures may increase the risk of unprovoked seizures and new onset epilepsy. This study aimed to synthesize the literature that has estimated the associations between short- and long-term exposure to outdoor air and noise pollution and the risk of unprovoked seizures and new onset epilepsy. We searched Embase, MEDLINE, Scopus, Web of Science, BIOSIS Previews, Latin American and Caribbean Health Sciences Literature, Proquest Dissertations and Theses, conference abstracts, and the gray literature and conducted citation tracing in June 2023. Observational and ecological studies assessing the associations of air and noise pollution with unprovoked seizures or new onset epilepsy were eligible. One reviewer extracted summary data. Using fixed and random effects models, we calculated the pooled risk ratios (RRs) for the studies assessing the associations between short-term exposure to air pollution and unprovoked seizures. Seventeen studies were included, 16 assessing the association of air pollution with seizures and one with epilepsy. Eight studies were pooled quantitatively. Ozone (O3; RR = .99, 95% confidence interval [CI] = .99-.99) and nitrogen dioxide (NO2) exposure adjusted for particulate matter (RR = 1.02, 95% CI = 1.01-1.02) on the same day, and carbon monoxide (CO) exposure 2 days prior (RR = 1.12, 95% CI = 1.02-1.22), were associated with seizure risk. A single study of air pollution and epilepsy did not report a significant association. The risk of bias and heterogeneity across studies was moderate or high. Short-term exposure to O3, NO2, and CO may affect the risk of seizures; however, the effect estimates for O3 and NO2 were minimal. Additional research should continue to explore these and the associations between outdoor air pollution and epilepsy and between noise pollution and seizures and epilepsy.

Emerging Trends in Neuropalliative Care: A Palliative Approach to Epilepsy and Seizure Management in Adults

Management of severe (drug-resistant) epilepsy and epilepsy in other serious illnesses is multidimensional and requires consideration of both physical symptoms and psychosocial distress that require individualized treatment. Palliative care offers a holistic approach to disease that focuses on all dimensions of suffering to maintain quality of life. Integration of a palliative care mind- and skillset in the management of severe epilepsy and epilepsy in other serious illnesses can provide person-centered care and support for families and caregivers.

Therapeutic potential of CB1R activation by Qingyangshen glycoside M1 for seizure relief

ETHNOPHARMACOLOGICAL RELEVANCE

Cynanchum otophyllum C.K.Schneid.PI.Wilson, commonly referred as ''Qingyangshen'' (QYS), is a traditional folk medicine from Yunnan, renowned for its efficacy in neurological and psychiatric disorders. Glycosides isolated from QYS have shown promise in alleviating epilepsy, however, mechanisms of action and specific molecular targets remain to be elucidated.

AIM OF THE STUDY

The study aimed to evaluate the anticonvulsant effects of Qingyangshen glycosides M1 (M1), a C21 steroidal glycoside from QYS, on pentylenetetrazol (PTZ)-induced convulsions in zebrafish (Danio rerio), and its neuroprotective effect on Glutamate (Glu)-induced damage to PC12 cells, and importantly to identify its potential molecular targets.

MATERIALS AND METHODS

To evaluate anticonvulsant activity of M1, 7 days-post-fertilization (7-dpf) animals were pretreated (by immersion) and then exposed to PTZ (10 mM) solution. Furthermore, Glu-induced PC12 cell damage was employed to investigate the neuroprotective and anti-apoptotic capacity. Cells were pretreated with various concentrations of M1 (0-10 μM) for 12 h and then co-treated with Glu (15 mM) for an additional 24 h. The cell viability, apoptosis rate and apoptosis-related proteins (p-PI3K, PI3K, Akt, p-Akt, CREB, p-CREB, BDNF, Bax and Bcl-2) were measured using CCK-8, annexin V/PI and Western blot assays. To model the expected interaction between M1 and candidate cannabinoid receptor type 1 (CB1R), ERK phosphorylation, molecular docking, and drug affinity responsive target stability (DARTS) techniques were employed. Finally, CB1R antagonist Rimonabant (Rim) was validated by co-administration in both zebrafish and cells to confirm the requirement of CB1R for M1 efficacy.

RESULTS

At a concentration of 400 μM, M1 dramatically reversed PTZ-induced convulsive-like behaviors in zebrafish, as evidenced by a significant reduction in locomotor activity. In the context of Glu-induced cytotoxicity, M1 (10 μM) demonstrated a notable increase in cell viability and suppressed apoptosis through modulation of the Bax/Bcl-2 ratio and activation of the PI3K/Akt/CREB/BDNF signaling axis. These effects were facilitated through CB1R activation. In contrast, Rim dampened the beneficial activities of M1 as a cannabinoid agonist.

CONCLUSIONS

These results demonstrated that M1 as a potential CB1R activator, exhibiting anticonvulsive effects in a PTZ-induced zebrafish model and neuroprotective properties via the PI3K/Akt/CREB/BDNF signaling axis in a Glu-induced PC12 cell injury model. Notably, the observed seizure relief attenuated by CB1R chemical antagonism.

Rapid eye movement sleep and epilepsy: exploring interactions and therapeutic prospects

While research interest in the relationship between sleep and epilepsy is growing, it primarily centres on the effects of non-rapid eye movement (NREM) sleep in favouring seizures. Nonetheless, a noteworthy aspect is the observation that, in the lives of patients with epilepsy, REM sleep represents the moment with the least epileptic activity and the lowest probability of having a seizure. Studies demonstrate a suppressive effect of phasic REM sleep on interictal epileptiform discharges, potentially offering insights into epilepsy localisation and management. Furthermore, epilepsy impacts REM sleep, with successful treatment correlating with improved REM sleep quality. Novel therapeutic strategies aim to harness REM's anti-epileptic effects, including pharmacological approaches targeting orexinergic systems and neuromodulation techniques promoting cortical desynchronisation. These findings underscore the intricate relationship between REM sleep and epilepsy, highlighting avenues for further research and therapeutic innovation in epilepsy management.

Channelopathies in epilepsy: an overview of clinical presentations, pathogenic mechanisms, and therapeutic insights

Pathogenic variants in genes encoding ion channels are causal for various pediatric and adult neurological conditions. In particular, several epilepsy syndromes have been identified to be caused by specific channelopathies. These encompass a spectrum from self-limited epilepsies to developmental and epileptic encephalopathies spanning genetic and acquired causes. Several of these channelopathies have exquisite responses to specific antiseizure medications (ASMs), while others ASMs may prove ineffective or even worsen seizures. Some channelopathies demonstrate phenotypic pleiotropy and can cause other neurological conditions outside of epilepsy. This review aims to provide a comprehensive exploration of the pathophysiology of seizure generation, ion channels implicated in epilepsy, and several genetic epilepsies due to ion channel dysfunction. We outline the clinical presentation, pathogenesis, and the current state of basic science and clinical research for these channelopathies. In addition, we briefly look at potential precision therapy approaches emerging for these disorders.

Dissecting the Shared Genetic Architecture of Common Epilepsies With Cortical Brain Morphology

Background and Objectives

Epilepsies are associated with differences in cortical thickness (TH) and surface area (SA). However, the mechanisms underlying these relationships remain elusive. We investigated the extent to which these phenotypes share genetic influences.

Methods

We analyzed genome-wide association study data on common epilepsies (n = 69,995) and TH and SA (n = 32,877) using Gaussian mixture modeling MiXeR and conjunctional false discovery rate (conjFDR) analysis to quantify their shared genetic architecture and identify overlapping loci. We biologically interrogated the loci using a variety of resources and validated in independent samples.

Results

The epilepsies (2.4 k-2.9 k variants) were more polygenic than both SA (1.8 k variants) and TH (1.3 k variants). Despite absent genome-wide genetic correlations, there was a substantial genetic overlap between SA and genetic generalized epilepsy (GGE) (1.1 k), all epilepsies (1.1 k), and juvenile myoclonic epilepsy (JME) (0.7 k), as well as between TH and GGE (0.8 k), all epilepsies (0.7 k), and JME (0.8 k), estimated with MiXeR. Furthermore, conjFDR analysis identified 15 GGE loci jointly associated with SA and 15 with TH, 3 loci shared between SA and childhood absence epilepsy, and 6 loci overlapping between SA and JME. 23 loci were novel for epilepsies and 11 for cortical morphology. We observed a high degree of sign concordance in the independent samples.

Discussion

Our findings show extensive genetic overlap between generalized epilepsies and cortical morphology, indicating a complex genetic relationship with mixed-effect directions. The results suggest that shared genetic influences may contribute to cortical abnormalities in epilepsies.

Combining magnetic resonance fingerprinting with voxel-based morphometric analysis to reduce false positives for focal cortical dysplasia detection

OBJECTIVE

We aim to improve focal cortical dysplasia (FCD) detection by combining high-resolution, three-dimensional (3D) magnetic resonance fingerprinting (MRF) with voxel-based morphometric magnetic resonance imaging (MRI) analysis.

METHODS

We included 37 patients with pharmacoresistant focal epilepsy and FCD (10 IIa, 15 IIb, 10 mild Malformation of Cortical Development [mMCD], and 2 mMCD with oligodendroglial hyperplasia and epilepsy [MOGHE]). Fifty-nine healthy controls (HCs) were also included. 3D lesion labels were manually created. Whole-brain MRF scans were obtained with 1 mm3 isotropic resolution, from which quantitative T1 and T2 maps were reconstructed. Voxel-based MRI postprocessing, implemented with the morphometric analysis program (MAP18), was performed for FCD detection using clinical T1w images, outputting clusters with voxel-wise lesion probabilities. Average MRF T1 and T2 were calculated in each cluster from MAP18 output for gray matter (GM) and white matter (WM) separately. Normalized MRF T1 and T2 were calculated by z-scores using HCs. Clusters that overlapped with the lesion labels were considered true positives (TPs); clusters with no overlap were considered false positives (FPs). Two-sample t-tests were performed to compare MRF measures between TP/FP clusters. A neural network model was trained using MRF values and cluster volume to distinguish TP/FP clusters. Ten-fold cross-validation was used to evaluate model performance at the cluster level. Leave-one-patient-out cross-validation was used to evaluate performance at the patient level.

RESULTS

MRF metrics were significantly higher in TP than FP clusters, including GM T1, normalized WM T1, and normalized WM T2. The neural network model with normalized MRF measures and cluster volume as input achieved mean area under the curve (AUC) of .83, sensitivity of 82.1%, and specificity of 71.7%. This model showed superior performance over direct thresholding of MAP18 FCD probability map at both the cluster and patient levels, eliminating ≥75% FP clusters in 30% of patients and ≥50% of FP clusters in 91% of patients.

SIGNIFICANCE

This pilot study suggests the efficacy of MRF for reducing FPs in FCD detection, due to its quantitative values reflecting in vivo pathological changes. © 2024 International League Against Epilepsy.

Antiseizure medication adherence and epilepsy surgery attitude in people with epilepsy in Morocco: A cross-sectional study

We determine the proportion of non-Antiseizure Medication Adherence (non-AMA) and refusal attitude towards Epilepsy Surgery (ES) and their associated factors in Moroccan People With Epilepsy (PWE). A cross-sectional study was conducted (December 2021-December 2022) among adult Moroccan PWE. PWE were interviewed for their reactions to AMA and the ES attitude. Their medical files were processed to complete their sociodemographic and clinical data. Data were analyzed by the Statistical Package for Social Sciences (SPSS) software 21.0. A Chi-square test was performed to compare variables and multivariate logistic regression was used to highlight associations. Statistical tests were considered significant at a p-value ≤ 0.05 for a Confidence Interval (CI) of 95 %. The median age of our sample (n = 294) was 38 years (IQR: 25.00-55.00). Non-AMA was noted in 24.5 % with indifference as the main reason (55.6 %). ES refusal was found in 33.3 %, attributed mostly to apprehension (61.2 %). In the multivariate analysis, male sex (aOR = 1.94; 95 %CI: 1.03-3.64) and the existence of a family history of epilepsy (aOR = 1.96; 95 %CI: 1.02-3.75) were the factors associated with the non-AMA, whereas the use of allopathic treatments (aOR = 2.32; 95 %CI: 1.20-4.51), exclusively focal or generalized (not combined) seizures (aOR = 2.66; 95 %CI: 1.36-5.21) and the combination of a generic with the originator ASM (aOR = 2.64; 95 %CI: 1.12-6.18) were the predictive factors with the ES refusal attitude. The proportions found of non-AMA and ES refusal were relatively low compared to other studies, which may indicate the effort that medical staff have devoted recently to raising awareness of the importance of PWE's therapeutic involvement.

Post-ictal Rhythmic Thalamic Activity of the Centromedian Nucleus

INTRODUCTION

Deep brain stimulation of the centromedian nucleus of the thalamus (CMN) to treat drug-resistant epilepsy has been of interest for decades. However, little is known about the electrophysiological activity of the CMN during seizures. We describe a novel CMN EEG finding associated with seizure: post-ictal rhythmic thalamic activity.

METHODS

Five patients with drug-resistant epilepsy of unknown etiology with focal onset seizures underwent stereoelectroencephalography monitoring as part of evaluation for potential resective surgery or neuromodulation. Two patients had previously undergone complete corpus callosotomy and vagus nerve stimulation. A standardized plan for implantation included targets in the bilateral CMN.

RESULTS

Each patient had frontal onset seizures, and two patients had additional insular, parietal, or mesial temporal onset seizures. Contacts of CMN were involved synchronously or rapidly after onset in most recorded seizures, particularly those with frontal onset. Focal onset hemiclonic and bilateral tonic-clonic seizures spread to involve cortical contacts with high-amplitude rhythmic spiking followed by abrupt offset with diffuse voltage attenuation. A post-ictal rhythmic 1.5 to 2.5 Hz delta frequency pattern, post-ictal rhythmic thalamic activity, emerged in CMN contacts amid the suppression of background activity in cortical contacts. In the two patients with corpus callosotomy, unilateral seizure spread and ipsilateral post-ictal rhythmic thalamic activity were observed.

CONCLUSIONS

We observed post-ictal rhythmic thalamic activity in five patients with stereoelectroencephalography monitoring of the CMN with convulsive seizures. This rhythm appears late in ictal evolution and may signal an important role of the CMN in seizure termination. Furthermore, this rhythm may help identify CMN involvement in the epileptic network.

Real-world evidence of epidemiology, patient characteristics, and mortality in people with drug-resistant epilepsy in the United Kingdom, 2011-2021

BACKGROUND

A third of people with epilepsy are drug resistant. People with drug-resistant epilepsy (DRE) have a higher risk of mortality and physical injuries than those who respond to anti-seizure medication (ASM). This study describes patient characteristics, comorbidities, and mortality in people with DRE in the UK.

METHODS

The Clinical Practice Research Datalink was utilised to select people with DRE prescribed a third ASM between 1 January 2011 and 31 March 2021. Annual incidence and prevalence of DRE, patient characteristics, comorbidities, and mortality rates were analysed. Subgroup analysis was performed by age, sex, presence of intellectual disabilities and time from epilepsy diagnosis to DRE.

RESULTS

A total of 34,647 people with DRE were included (mean ± SD age 42.68 ± 23.59 years, 52.6% females). During the study period, annual DRE incidence ranged from 1.99% to 3.12%. As of 31 March 2021, DRE prevalence was 26.6% (95% confidence interval [CI] 26.3%-26.8%). A greater proportion of people with DRE resided in the most deprived regions, with 21.1% and 16.7% in the top two quintiles of the Index of Multiple Deprivation respectively, compared to < 15% in the three less deprived regions. All-cause mortality ranged from 3,687 to 4,802 per 100,000 persons with DRE, four times higher than that in the general population in the UK. Variations existed across subgroups.

CONCLUSIONS

Considerable disease burden was observed in people with DRE in the UK. The findings emphasise the importance of early DRE diagnosis and appropriate disease management in people who develop DRE.

Low-frequency Stimulation at the Subiculum Prevents Extensive Secondary Epileptogenesis in Temporal Lobe Epilepsy

Secondary epileptogenesis is characterized by increased epileptic susceptibility and a tendency to generate epileptiform activities outside the primary focus. It is one of the major resultants of pharmacoresistance and failure of surgical outcomes in epilepsy, but still lacks effective treatments. Here, we aimed to test the effects of low-frequency stimulation (LFS) at the subiculum for secondary epileptogenesis in a mouse model. Here, secondary epileptogenesis was simulated at regions both contralateral and ipsilateral to the primary focus by applying successive kindling stimuli. Mice kindled at the right CA3 showed higher seizure susceptibilities at both the contralateral CA3 and the ipsilateral entorhinal cortex and had accelerated kindling processes compared with naive mice. LFS at the ipsilateral subiculum during the primary kindling progress at the right CA3 effectively prevented secondary epileptogenesis at both the contralateral CA3 and the ipsilateral entorhinal cortex, characterized by decreased seizure susceptibilities and a retarded kindling process at those secondary foci. Only application along with the primary epileptogenesis was effective. Notably, the effects of LFS on secondary epileptogenesis were associated with its inhibitory effect at the secondary focus through interfering with the enhancement of synaptic connections between the primary and secondary foci. These results imply that LFS at the subiculum is an effective preventive strategy for extensive secondary epileptogenesis in temporal lobe epilepsy and present the subiculum as a target with potential translational importance.

A systematic review of the Mozart effect in adult and paediatric cases of drug-resistant epilepsy: A sound approach to epilepsy management

OBJECTIVES

In recent years, adjunctive therapies for epilepsy management are being explored due to considerable side effects carried by antiepileptic drugs (AEDs) and widespread reports of drug-resistant epilepsy. One such approach is non-invasive musical neurostimulation. Within this context, Mozart's sonata K448 has received particular attention following reports of reduced seizure frequency and a decrease in epileptiform discharges during and after music exposure; often described as the 'Mozart effect'. However, controversy exists around the effectiveness of K448 in epilepsy and the strength and quality of the evidence supporting it. Therefore, this study aims to systematically review the available literature around the Mozart effect, in both adult and paediatric cases of epilepsy.

METHODS

We carried out a literature search on PubMed, Science Direct, Scopus and Web of Science using the query string ALL= (Mozart AND epileps*). Selected clinical studies were classified based on the age of the population studied, as paediatric (0-18 years), adult (19 years or older) or a combination of the two. All the studies were evaluated using the Johns Hopkins Nursing Evidence-Based Practice (JHNEBP) rating scale to determine the strength of the evidence (level) and the quality of the research evidence.

RESULTS

Out of 538 records, 25 studies were selected, grouped based on the age of the population studied and evaluated using the JHNEBP rating scale. Ten level 1 studies, which represent the strongest evidence, were identified, including six RCTs and three meta-analyses. Nine of these ten studies show a decrease in epileptiform discharges and in seizure frequency following exposure to Mozart's K448. One multiverse analysis reported lack of statistically significant evidence to support the use of K448 in epilepsy or any other medical condition.

CONCLUSIONS

A growing body of evidence supports the Mozart effect on epilepsy, with notable studies including RCTs and comprehensive meta-analyses. This review identified nine level 1 studies, conducted by research groups worldwide, which endorse the use of Mozart's music to reduce seizures and epileptiform discharges in adult and paediatric epilepsy patients. However, existing research exhibits limitations like varying protocols, small sample sizes and diverse treatment regimens. Additionally, studies that combine adult and paediatric patients fail to take account of developmental differences between these two groups - particularly with regards to brain maturation and neurophysiology - which could negatively impact upon the accuracy of findings by obscuring important age-related differences in response to intervention. Adequately addressing these limitations will be crucial to demonstrating proof of concept; otherwise, a potentially valuable, non-invasive, accessible, and affordable therapeutic option for drug-resistant epilepsy will remain on the medical fringe. Further research with larger samples and stricter protocols, particularly considering patient age and drug regimens, is required.

Heparin-Modified Superparamagnetic Iron Oxide Nanoparticles Suppress Lithium Chloride/Pilocarpine-Induced Temporal Lobe Epilepsy in Rats through Attenuation of Inflammation and Oxidative Stress

The development of antiepileptic drugs is still a long process. In this study, heparin-modified superparamagnetic iron oxide nanoparticles (UFH-SPIONs) were prepared, and their antiepileptic effect and underlying mechanism were investigated. UFH-SPIONs are stable, homogeneous nanosystems with antioxidant enzyme activity that are able to cross the blood-brain barrier (BBB) and enriched in hippocampal epileptogenic foci. The pretreatment with UFH-SPIONs effectively prolonged the onset of seizures and reduced seizure severity after lithium/pilocarpine (LP)-induced seizures in rats. The pretreatment with UFH-SPIONs significantly decreased the expression of inflammatory factors in hippocampal tissues, including IL-6, IL-1β, and TNF-α. LP-induced oxidative stress in hippocampal tissues was in turn reduced upon pretreatment with UFH-SPIONs, as evidenced by an increase in the levels of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) and a decrease in the level of lipid peroxidation (MDA). Moreover, the LP-induced upregulation of apoptotic cells was decreased upon pretreatment with UFH-SPIONs. Together, these observations suggest that the pretreatment with UFH-SPIONs ameliorates LP-induced seizures and downregulates the inflammatory response and oxidative stress, which exerts neuronal protection during epilepsy.

Drug resistant epilepsies: A multicentre case series of steroid therapy

PURPOSE

Our study aimed to evaluate the effectiveness of corticosteroids on seizure control in drug-resistant epilepsies (DREs). Our primary goal was to assess the response to steroids for various underlying etiologies, interictal electroencephalographic (EEG) patterns and electroclinical seizure descriptions. Our second goal was to compare steroid responsiveness to different treatment protocols.

METHODS

This is a retrospective multicentre cohort study conducted according to the STROBE guidelines (Strengthening the Reporting of Observational Studies in Epidemiology). The following data were collected for each patient: epilepsy etiology, interictal EEG pattern, seizure types and type of steroid treatment protocol administered.

RESULTS

Thirty patients with DRE were included in the study. After 6 months of therapy, 62.7 % of patients experienced reduced seizure frequency by 50 %, and 6.6 % of patients experienced complete seizure cessation. Findings associated with favourable response to steroids included structural/lesional etiology of epilepsy, immune/infectious etiology and focal interictal abnormalities on EEG. Comparing four different steroid treatment protocols, the most effective for seizure control was treatment with methylprednisolone at the dose of 30 mg/kg/day administered for 3 days, leading to greater than 50 % seizure reduction at 6 months in 85.7 % of patients. Treatment with dexamethasone 6 mg/day for 5 days decreased seizure frequency in 71.4 % of patients. Hydrocortisone 10 mg/kg administered for 3 months showed a good response to treatment in 71 %.

CONCLUSIONS

In our study, two-thirds of patients with DRE experienced a significant seizure reduction following treatment with steroids. We suggest considering steroids as a potential therapeutic option in children with epilepsy not responding to conventional antiseizure medicines (ASM).

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

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

Use of cannabidiol in the treatment of drug-refractory epilepsy in children and young adults: A systematic review

Objectives

Epilepsy poses a significant challenge in pediatric and adolescent populations, impacting not only seizures but also psychological and cognitive comorbidities, leading to higher mortality rates than the general population. Drug-refractory epilepsy, resistant to conventional treatments, affects a range of 7-20% of pediatric patients. The search for alternative therapies has led to exploring the therapeutic potential of Cannabis sativa L. compounds, particularly cannabidiol (CBD). Examine the use of CBD for treating drug-refractory epilepsy in children and young adults, summarizing existing evidence on its efficacy.

Materials and Methods

A systematic review, following Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, assessed studies from 2018 to 2023, focusing on CBD's efficacy and safety for treatment-resistant epilepsy in pediatric and juvenile populations. The search spanned seven databases, and the studies underwent rigorous screening and data extraction.

Results

Out of 6351 identified articles, eight were selected for review. The included studies reported positive outcomes, with CBD leading to a reduction in seizure frequency ranging from 50% to complete seizure freedom. Adverse effects were mostly mild and reversible, including drowsiness, diarrhea, and loss of appetite.

Conclusion

The CBD emerges as a promising tool for refractory epilepsy in pediatric patients, showing efficacy in reducing seizure frequency and improving overall quality of life. Despite mild and reversible adverse effects, CBD's benefits outweigh the risks. However, more research on long-term effects is needed to fully understand its implications.

Predictors of medical intractability in children with epilepsy onset during the first two years of life, excluding infantile epileptic spasm syndrome

PURPOSE

Early childhood epilepsy presents a significant challenge, with approximately 30 % of individuals experiencing treatment failure. This study aimed to identify predictors of medical intractability in children with epilepsy onset during the first two years of life, excluding infantile epileptic spasm syndrome.

METHODS

A total of 323 children were retrospectively evaluated. The analyses included a review of medical records for demographic, laboratory, radiological, and electroencephalographic (EEG) findings. Children were diagnosed with drug-resistant epilepsy (DRE) according to the ILAE diagnostic criteria. Twenty-one potential prognostic predictors were examined in relation to medical intractability.

RESULTS

Among the 323 children (56.7 % male), 119 (36.8 %) had unknown epilepsy, 131 (40.6 %) had structural epilepsy, 53 (16.4 %) had genetic epilepsy, and 20 (6.2 %) had metabolic epilepsy. Over a median follow-up of 68 months, 55.4 % of the children achieved ≥6 months of seizure freedom, 33.1 % developed DRE, and the remaining 11.5 % had rare ongoing seizures but did not meet the criteria for DRE because they were only treated with one antiseizure medication at the last follow-up. Univariate logistic regression analyses identified ten risk factors significantly associated with DRE. Multivariate logistic regression analyses revealed that the presence of developmental delay at epilepsy onset (p = 0.000; OR 7.890; 95 %CI 2.713 to 22.945), history of status epilepticus (p = 0.000; OR 8.247; 95 %CI 3.619 to 18.793), number of antiseizure medications (ASMs) at the sixth month of diagnosis (p = 0.000; OR 20.585; 95 %CI 8.993 to 47.117), and initial EEG findings (p = 0.046; OR 2.366; 95 %CI 1.015 to 5.518) were predictors of medical intractability. Nineteen (5.9 %) children died during follow-up for various reasons, including progressive neurogenetic or neurodegenerative disorders.

CONCLUSION

Developmental delay at epilepsy onset, a history of status epilepticus, the use of two or more ASMs in the sixth month of diagnosis, and abnormal initial EEG findings were associated with medical intractability.

Drug resistant epilepsy and ketogenic diet: A narrative review of mechanisms of action

Drug-resistant epilepsy (DRE) poses a significant global challenge, impacting the well-being of patients. Anti-epileptic drugs often fail to effectively control seizures in individuals with DRE. This condition not only leads to persistent seizures but also induces neurochemical imbalances, elevating the risk of sudden unexpected death in epilepsy and comorbidities. Moreover, patients experience mood and personality alterations, educational and vocational setbacks, social isolation, and cognitive impairments. Ketogenic diet has emerged as a valuable therapeutic approach for DRE, having been utilized since 1920. Various types of ketogenic diets have demonstrated efficacy in controlling seizures. By having a multimodal mechanism of action, the ketogenic diet reduces neuronal excitability and the frequency of seizure episodes. In our narrative review, we have initially provided a concise overview of the factors contributing to drug resistance in epilepsy. Subsequently, we have discussed the different available ketogenic diets. We have reviewed the underlying mechanisms through which the ketogenic diet operates. These mechanisms encompass decreased neuronal excitability, enhanced mitochondrial function, alterations in sleep patterns, and modulation of the gut microbiome. Understanding the complex mechanisms by which this diet acts is essential as it is a rigorous diet and requires good compliance. Hence knowledge of the mechanisms may help to advance research on achieving similar therapeutic effects through other less stringent approaches.

Benzodiazepines for pediatric epilepsies and their risks in a cohort within the French health care data

OBJECTIVE

The management of antiseizure treatment in patients with epilepsy relies on the benefit-risk ratio. Data on antiseizure medication (ASM) use in children are limited. We described antiseizure medication use in children with epilepsy (CwE) in France, with a focus on the chronic use of benzodiazepines and related implications.

METHODS

We conducted a 5-year cohort study from January 2012, using data from the French national health care data system (Système National des Données de Santé). We included CwE identified through International Classification of Diseases, 10th Revision codes and medications from January 2012 to December 2015 and followed them until December 2016. We described ASMs and assessed whether the risk of initiating a polytherapy after a bitherapy depends on whether benzodiazepine was included in the bitherapy.

RESULTS

We identified 62 885 CwE. Valproate was the most reimbursed ASM (40%), followed by lamotrigine (17.6%), levetiracetam (9.3%), clobazam (6.1%), and carbamazepine (5.8%). Prescriptions were initiated at the hospital in 74.5% of CwE. We observed a decrease in the number of CwE with at least one benzodiazepine reimbursement from 15.3% in 2013 to 10.1% in 2016 (p < .0001). The prevalence of CwE with levetiracetam reimbursements increased, whereas that of CwE with valproate decreased. A switch from a bitherapy to a polytherapy was more likely when the bitherapy included a benzodiazepine (subdistribution hazard ratio [sHR] = 1.20 [1.03-1.39]).

SIGNIFICANCE

The prevalence of CwE with at least one benzodiazepine reimbursement decreased during the study period. Benzodiazepines were associated with an increased use of subsequent ASM polytherapy.

Pediatric neuromodulation for drug-resistant epilepsy: Survey of current practices, techniques, and outcomes across US epilepsy centers

Neuromodulation via Responsive Neurostimulation (RNS) or Deep Brain Stimulation (DBS) is an emerging treatment strategy for pediatric drug-resistant epilepsy (DRE). Knowledge gaps exist in patient selection, surgical technique, and perioperative care. Here, we use an expert survey to clarify practices. Thirty-two members of the Pediatric Epilepsy Research Consortium were surveyed using REDCap. Respondents were from 17 pediatric epilepsy centers (missing data in one): Four centers implant RNS only while 13 implant both RNS and DBS. Thirteen RNS programs commenced in or before 2020, and 10 of 12 DBS programs began thereafter. The busiest six centers implant 6-10 new RNS devices per year; all DBS programs implant <5 annually. The youngest RNS patient was 3 years old. Most centers (11/12) utilize MP2RAGE and/or FGATIR sequences for planning. Centromedian thalamic nuclei were the unanimous target for Lennox-Gastaut syndrome. Surgeon exposure to neuromodulation occurred mostly in clinical practice (14/17). Clinically significant hemorrhage (n = 2) or infection (n = 3) were rare. Meaningful seizure reduction (>50%) was reported by 81% (13/16) of centers. RNS and DBS are rapidly evolving treatment modalities for safe and effective treatment of pediatric DRE. There is increasing interest in multicenter collaboration to gain knowledge and facilitate dialogue. PLAIN LANGUAGE SUMMARY: We surveyed 32 pediatric epilepsy centers in USA to highlight current practices of intracranial neuromodulation. Of the 17 that replied, we found that most centers are implanting thalamic targets in pediatric drug-resistant epilepsy using the RNS device. DBS device is starting to be used in pediatric epilepsy, especially after 2020. Different strategies for target identification are enumerated. This study serves as a starting point for future collaborative research.

Understanding Health Care Provider Burnout When Caring for Patients With Refractory Epilepsy in the United States

Background and Objectives

Among health care providers (HCPs), neurologists have one of the highest rates of burnout in the United States, compromising the quality and accessibility of patient care. Patients with refractory epilepsy are especially challenging to treat. This study aims to understand the burnout level in neurologists treating patients with refractory epilepsy and identify key contributing factors.

Methods

US board-certified pediatric/adult neurologists who devote ≥50% of their time to clinical practice and treat ≥10 unique patients with refractory epilepsy annually were invited to take a noninterventional quantitative survey, designed to capture key elements of the HCP's background, burnout level, current practice, burden domains, and satisfaction with current antiseizure medications (ASMs). Burnout in 3 domains (emotional exhaustion, depersonalization, and personal accomplishment) was assessed by the validated Maslach Burnout Inventory-Human Services Survey.

Results

From March 11, 2022, to April 10, 2022, a total of 138 neurology-specialist HCPs participated in the survey, divided between adult epileptologists (n = 44), adult neurologists (n = 41), pediatric epileptologists (n = 36), and pediatric neurologists (n = 17). Of participating HCPs, 61% experienced at least some burnout (≥1 of 3 burnout domains categorized as high), and 4% experienced high burnout (3 of 3 burnout domains categorized as high). High burnout levels were driven by high pediatric and inpatient caseloads and unexpected pediatric patient reluctance to transition to adult care. HCPs with high burnout had a higher yearly caseload of patients with refractory epilepsy. Most HCPs (approximately 90%) indicated that patients with refractory epilepsy were more difficult to manage than those with nonrefractory epilepsy. The proportion of HCPs satisfied or extremely satisfied with ASMs was lower for patients with refractory epilepsy (20%) than that for patients with nonrefractory epilepsy (73%). Dissatisfaction was mostly due to workload and latency of the insurance approval process, out-of-pocket costs, and poor efficacy, safety, and tolerability. For 32% of HCPs, stopping practicing or moving to another practice within 5 years was probable or very probable.

Discussion

Some burnout is common among HCPs who treat patients with refractory epilepsy. However, management of refractory epilepsy is challenging, and satisfaction with available ASMs is low. Thus, addressing these contributing factors may help to alleviate HCP burnout.

Serum biomarkers in patients with drug-resistant epilepsy: a proteomics-based analysis

Objective

To investigate the serum biomarkers in patients with drug-resistant epilepsy (DRE).

Methods

A total of 9 DRE patients and 9 controls were enrolled. Serum from DRE patients was prospectively collected and analyzed for potential serum biomarkers using TMT18-labeled proteomics. After fine quality control, bioinformatics analysis was conducted to find differentially expressed proteins. Pathway enrichment analysis identified some biological features shared by differential proteins. Protein-protein interaction (PPI) network analysis was further performed to discover the core proteins.

Results

A total of 117 serum differential proteins were found in our study, of which 44 were revised upwards and 73 downwards. The up-regulated proteins mainly include UGGT2, PDIA4, SEMG1, KIAA1191, CCT7 etc. and the down-regulated proteins mainly include ROR1, NIF3L1, ITIH4, CFP, COL11A2 etc. Pathway enrichment analysis identified that the upregulated proteins were mainly enriched in processes such as immune response, extracellular exosome, serine-type endopeptidase activity and complement and coagulation cascades, and the down-regulated proteins were enriched in signal transduction, extracellular exosome, zinc/calcium ion binding and metabolic pathways. PPI network analysis revealed that the core proteins nodes include PRDX6, CAT, PRDX2, SOD1, PARK7, GSR, TXN, ANXA1, HINT1, and S100A8 etc.

Conclusion

The discovery of these differential proteins enriched our understanding of serum biomarkers in patients with DRE and potentially provides guidance for future targeted therapy.

Etiological analysis of 167 cases of drug-resistant epilepsy in children

BACKGROUND

To analyze the etiological distribution characteristics of drug-resistant epilepsy (DRE) in children, with the aim of providing valuable perspectives to enhance clinical practice.

METHODS

In this retrospective study, clinical data were collected on 167 children with DRE who were hospitalized between January 2020 and December 2022, including gender, age of onset, seizure types, video electroencephalogram(VEEG) recordings, neuroimaging, and genetic testing results. Based on the etiology of epilepsy, the enrolled children were categorized into different groups. The rank-sum test was conducted to compare the age of onset for different etiologies.

RESULTS

Of the 167 cases, 89 (53.3%) had a clear etiology. Among them, structural factors account for 23.4%, genetic factors for 19.2%, multiple factors for 7.2%, and immunological factors for 3.6%. The age of onset was significantly earlier in children with genetic causes than those with structural (P < 0.001) or immunological (P = 0.001) causes.

CONCLUSIONS

More than half of children with DRE have a distinct underlying cause, predominantly attributed to structural factors, followed by genetic factors. Genetic etiology primarily manifests at an early age, especially among children aged less than one year. This underscores the need for proactive enhancements in genetic testing to unveil the underlying causes and subsequently guide treatment protocols.

Variation in access to specialist services for neurosurgical procedures in adults with epilepsy in England, a cohort study

PURPOSE

To understand if primary consultation at tertiary epilepsy centres (TEC) in England impacts access to neurosurgical procedures (resective surgery, vagus nerve stimulator [VNS], deep brain stimulator [DBS]).

METHODS

Adults with epilepsy, and with a first neurology outpatient visit (index) between 01/01/2013 and 31/12/2015, were followed using English Hospital Episode Statistics from index date to 31/12/2019. Analyses were stratified by geographic location, learning disability record, and whether the index or follow-up visits were at a TEC.

RESULTS

84,093 people were included, with mean 5.5 years of follow-up. 12.4% of the cohort had learning disability (range 10.1%-17.4% across regions). TEC consultations varied by National Health Service regions and Clinical Commissioning Groups. 37.5% of people (11.2%-75.0% across regions) had their index visit at a TEC; and, of those not initially seen at a TEC, 10.6% (6.5%-17.7%) subsequently attended a tertiary centre. During follow-up, 11.1% people (9.5%-13.2%) visited a neurosurgery department, and 2.3% of those (0.9%-5.0%) then underwent a neurosurgical procedure, mainly VNS implantation. Median time from index date to first visit at a neurosurgery centre was 7 months (range 6-8 months across regions) and 40 months to procedure (36.5-49 months, 37.0 months in people with index visit at a TEC and 49.0 months otherwise). People with learning disability were less likely to have resective surgery (<0.5% versus 1.0% in those without) and more likely to undergo VNS implantation (5.8% versus 0.8%).

CONCLUSION

Although clinically recommended for suitable individuals, neurosurgical procedures in epilepsy remain uncommon even after consultation at a TEC. Geographical variation in access to TECs was present.

Polysaccharide-rich extract of Genipa americana leaves protects seizures and oxidative stress in the mice model of pentylenetetrazole-induced epilepsy

Plant polysaccharides have biological activities in the brain and those obtained from Genipa americana leaves present antioxidant and anticonvulsant effects in the mice model of pentylenetetrazole (PTZ)-induced acute seizures. This study aimed to evaluate the polysaccharide-rich extract of Genipa americana leaves (PRE-Ga) in the models of acute seizures and chronic epilepsy (kindling) induced by PTZ. In the acute seizure model, male Swiss mice (25-35 g) received PRE-Ga (1 or 9 mg/kg; intraperitoneal- IP), alone or associated with diazepam (0.01 mg/kg), 30 min before induction of seizures with PTZ (70 mg/kg; IP). In the chronic epilepsy model, seizures were induced by PTZ (40 mg/kg) 30 min after treatment and in alternated days up to 30 days and evaluated by video. Brain areas (prefrontal cortex, hippocampus, striatum) were assessed for inflammatory and oxidative stress markers. Diazepam associated to PRE-Ga (9 mg/kg; i.p.) increased the latency of seizures in acute (222.4 ± 47.57 vs. saline: 62.00 ± 4.709 s) and chronic models (6.267 ± 0.502 vs. saline: 4.067 ± 0.407 s). In hippocampus, PRE-Ga (9 mg/kg) inhibited TNF-α (105.9 ± 5.38 vs. PTZ: 133.5 ± 7.62 pmol/g) and malondialdehyde (MDA) (473.6 ± 60.51) in the chronic model. PTZ increased glial fibrillar acid proteins (GFAP) and Iba-1 in hippocampus, which was reversed by PRE-Ga (GFAP: 1.9 ± 0.23 vs PTZ: 3.1 ± 1.3 and Iba-1: 2.2 ± 0.8 vs PTZ: 3.2 ± 1.4). PRE-Ga presents neuroprotector effect in the mice model of epilepsy induced by pentylenetetrazole reducing seizures, gliosis, inflammatory cytokines and oxidative stress.

Epilepsy and epileptiform activity in late-onset Alzheimer disease: clinical and pathophysiological advances, gaps and conundrums

A growing body of evidence has demonstrated a link between Alzheimer disease (AD) and epilepsy. Late-onset epilepsy and epileptiform activity can precede cognitive deterioration in AD by years, and its presence has been shown to predict a faster disease course. In animal models of AD, amyloid and tau pathology are linked to cortical network hyperexcitability that precedes the first signs of memory decline. Thus, detection of epileptiform activity in AD has substantial clinical importance as a potential novel modifiable risk factor for dementia. In this Review, we summarize the epidemiological evidence for the complex bidirectional relationship between AD and epilepsy, examine the effect of epileptiform activity and seizures on cognition in people with AD, and discuss the precision medicine treatment strategies based on the latest research in human and animal models. Finally, we outline some of the unresolved questions of the field that should be addressed by rigorous research, including whether particular clinicopathological subtypes of AD have a stronger association with epilepsy, and the sequence of events between epileptiform activity and amyloid and tau pathology.

Usefulness of Robotic Stereotactic Assistance (ROSA®) Device for Stereoelectroencephalography Electrode Implantation: A Systematic Review and Meta-analysis

The aim of this study was to systematically review and meta-analyze the efficiency and safety of using the Robotic Stereotactic Assistance (ROSA®) device (Zimmer Biomet; Warsaw, IN, USA) for stereoelectroencephalography (SEEG) electrode implantation in patients with drug-resistant epilepsy. Based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a literature search was carried out. Overall, 855 nonduplicate relevant articles were determined, and 15 of them were selected for analysis. The benefits of the ROSA® device use in terms of electrode placement accuracy, as well as operative time length, perioperative complications, and seizure outcomes, were evaluated. Studies that were included reported on a total of 11,257 SEEG electrode implantations. The limited number of comparative studies hindered the comprehensive evaluation of the electrode implantation accuracy. Compared with frame-based or navigation-assisted techniques, ROSA®-assisted SEEG electrode implantation provided significant benefits for reduction of both overall operative time (mean difference [MD], -63.45 min; 95% confidence interval [CI] from -88.73 to -38.17 min; P < 0.00001) and operative time per implanted electrode (MD, -8.79 min; 95% CI from -14.37 to -3.21 min; P = 0.002). No significant differences existed in perioperative complications and seizure outcomes after the application of the ROSA® device and other techniques for electrode implantation. To conclude, the available evidence shows that the ROSA® device is an effective and safe surgical tool for trajectory-guided SEEG electrode implantation in patients with drug-resistant epilepsy, offering benefits for saving operative time and neither increasing the risk of perioperative complications nor negatively impacting seizure outcomes.

The longitudinal effects of cannabidiol on brain temperature in patients with treatment-resistant epilepsy

Neuroinflammation (NI) is a key pathophysiological contributor to treatment-resistant epilepsy (TRE) that remains challenging to observe in vivo. Magnetic resonance spectroscopic imaging and thermometry (MRSI-t) is an emerging technique that can be used to non-invasively map brain temperature, whereby brain temperature elevations serve as a surrogate for the cellular and biochemical processes associated with NI. In a previous multimodal imaging study of focal epilepsy patients, we observed MRSI-t-based brain temperature elevations ipsilateral to the seizure onset zone (SOZ) that were concordant with evidence of edema (Sharma et al., 2023). Despite its potential as tool, it is unclear if MRSI-t can monitor changes in brain temperature in response to treatment. We imaged 25 participants approximately 12-weeks apart. Eight patients with TRE were imaged before receiving highly-purified pharmaceutical grade cannabidiol (CBD; pre-CBD) and after 12-weeks of CBD (on-CBD) therapy. Seventeen healthy controls (HCs) were also imaged twice. Repeated measures t-tests computed changes in TRE patients' seizure symptoms, mood, and brain temperature within their respective SOZs. Repeated measures ANOVAs tested Group*Time changes in imaging data. Participants with TRE had abnormally high peak brain temperatures within their SOZs that decreased after CBD initiation (p < 0.0001). Seizure severity scores also improved after CBD initiation (p < 0.001). These findings provide insights into the possible neural effects of CBD, and further demonstrate MRSI-t's potential as a tool for delineating SOZ. Further investigations into MRSI-t as a longitudinal measure of therapy-induced changes in NI are warranted.

Long-term efficacy and safety of perampanel as an add-on therapy in patients with epilepsy

BACKGROUND

Perampanel (PER) is a newly developed amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) receptor antagonist that has been globally approved for the treatment of both focal and generalized seizures. The efficacy and safety of PER have only been reported over short periods of treatment so far. This study aims to clarify the long-term efficacy and safety of PER as an add-on therapy.

METHOD

This retrospective observational study investigated 176 epilepsy patients who received PER as add-on medical therapy in two Japanese epilepsy centers between June 2016 and July 2022. The adherence, seizure frequency, and plasma concentration of PER were evaluated at three time points: 6 months, 12 months, and 24 months or longer after the start of adjunctive PER treatment.

RESULTS

112 patients undergoing PER treatment were evaluated at 6 months, 86 were evaluated at 12 months, and 52 were evaluated at 24 months or longer. Overall, 42.9 % (48/112), 45.4 % (40/86), and 44.2 % (23/52) of the patients were seizure-free at 6, 12, and 24 months or longer, respectively. The rate of PER tolerance was 78.3 %, 69.9 %, and 54.7 % at 6, 12, and 24 months or longer, respectively. At the latest timepoint, the seizure-free group was taking a significantly lower dose of PER than the seizure-remnant group, and the number of anti-seizure medications (ASMs) was associated with seizure outcomes. In addition, the seizure-free rate was significantly higher in patients who received PER as a first add-on than in those who received it as a late add-on. No significant difference was found in the plasma concentration of PER between the seizure-free and seizure-remnant groups at 24 months or longer. Among the patients receiving PER at dose of 2 mg, however, the plasma concentrations were significantly higher in the seizure-free group than in the seizure-remnant group (282.7 ± 109.8 μg/ml vs 94.7 ± 54.9 μg/ml, p = 0.0024).

CONCLUSION

This long-term retrospective observational study provides evidence of the efficacy and safety of PER over 2 years treatment period in Japan. Notably, patients who started on PER as the first add-on showed a better seizure outcome than those who received it as a late add-on over the long term. Measured plasma concentrations may provide valuable guidance for the management of patients. Higher plasma concentration at low dose PER may suggest the better seizure control.

On-demand low-frequency stimulation for seizure control: efficacy and behavioural implications

Mesial temporal lobe epilepsy (MTLE), the most common form of focal epilepsy in adults, is often refractory to medication and associated with hippocampal sclerosis. Deep brain stimulation represents an alternative treatment option for drug-resistant patients who are ineligible for resective brain surgery. In clinical practice, closed-loop stimulation at high frequencies is applied to interrupt ongoing seizures, yet has (i) a high incidence of false detections; (ii) the drawback of delayed seizure-suppressive intervention; and (iii) limited success in sclerotic tissue. As an alternative, low-frequency stimulation (LFS) has been explored recently in patients with focal epilepsies. In preclinical epilepsy models, hippocampal LFS successfully prevented seizures when applied continuously. Since it would be advantageous to reduce the stimulation load, we developed a protocol for on-demand LFS. Given the importance of the hippocampus for navigation and memory, we investigated potential consequences of LFS on hippocampal function. To this end, we used the intrahippocampal kainate mouse model, which recapitulates the key features of MTLE, including spontaneous seizure activity and hippocampal sclerosis. Specifically, our online detection algorithm monitored epileptiform activity in hippocampal local field potential recordings and identified short epileptiform bursts preceding focal seizure clusters, triggering hippocampal LFS to stabilize the network state. To probe behavioural performance, we tested the acute influence of LFS on anxiety-like behaviour in the light-dark box test, spatial and non-spatial memory in the object location memory and novel object recognition test, as well as spatial navigation and long-term memory in the Barnes maze. On-demand LFS was almost as effective as continuous LFS in preventing focal seizure clusters but with a significantly lower stimulation load. When we compared the behavioural performance of chronically epileptic mice to healthy controls, we found that both groups were equally mobile, but epileptic mice displayed an increased anxiety level, altered spatial learning strategy and impaired memory performance. Most importantly, with the application of hippocampal LFS before behavioural training and test sessions, we could rule out deleterious effects on cognition and even show an alleviation of deficits in long-term memory recall in chronically epileptic mice. Taken together, our findings may provide a promising alternative to current therapies, overcoming some of their major limitations, and inspire further investigation of LFS for seizure control in focal epilepsy syndromes.

Boltless nylon-suture technique for stereotactic electroencephalography as a safe, effective alternative when the anchor bolt is inappropriate

BACKGROUND

The use of anchor bolts to secure electrodes to the skull can be difficult in some clinical situations. Herein, we present the boltless technique to secure electrodes to the scalp using nylon sutures to overcome the problems associated with anchor bolts. We investigated the safety, accuracy errors, and patient-related and operative factors affecting errors in the boltless technique.

METHODS

This single-institution retrospective series analyzed 103 electrodes placed in 12 patients. The target-point localization error (TPLE), entry-point localization error (EPLE), radial error (RE), and depth error (DE) of the electrodes were calculated.

RESULTS

The median of the mean operative time per electrode was 9.3 min. The median TPLE, EPLE, RE, and absolute DE value were 4.1 mm, 1.6 mm, 2.7 mm, and 1.9 mm, respectively. Positive correlations were observed between the preoperative scalp thickness, mean operative time per electrode, EPLE, RE, and the absolute value of DE versus TPLE (r = .228, p = .02; r = .678, p = .015; r = .228, p = .02; r = .445, p < .01; r = .630, p < .01, respectively), and electrode approach angle versus EPLE (r = .213, p = .031). Multivariate analysis revealed that the absolute value of DE had the strongest influence on the TPLE, followed by RE and preoperative scalp thickness, respectively (β = .938, .544, .060, respectively, p < .001). No complications related to SEEG insertion and monitoring were encountered.

CONCLUSION

The boltless technique using our unique planning and technical method is a safe, effective, and low-cost alternative in cases where anchor bolts are contraindicated.

Pathophysiology to Risk Factor and Therapeutics to Treatment Strategies on Epilepsy

Epilepsy represents a condition in which abnormal neuronal discharges or the hyperexcitability of neurons occur with synchronicity, presenting a significant public health challenge. Prognostic factors, such as etiology, electroencephalogram (EEG) abnormalities, the type and number of seizures before treatment, as well as the initial unsatisfactory effects of medications, are important considerations. Although there are several third-generation antiepileptic drugs currently available, their multiple side effects can negatively affect patient quality of life. The inheritance and etiology of epilepsy are complex, involving multiple underlying genetic and epigenetic mechanisms. Different neurotransmitters play crucial roles in maintaining the normal physiology of different neurons. Dysregulations in neurotransmission, due to abnormal transmitter levels or changes in their receptors, can result in seizures. In this review, we address the roles played by various neurotransmitters and their receptors in the pathophysiology of epilepsy. Furthermore, we extensively explore the neurological mechanisms involved in the development and progression of epilepsy, along with its risk factors. Furthermore, we highlight the new therapeutic targets, along with pharmacological and non-pharmacological strategies currently employed in the treatment of epileptic syndromes, including drug interventions employed in clinical trials related to epilepsy.

Drug resistant epilepsy and associated factors among children with epilepsies in tanzania: a cross-sectional study

BACKGROUND

Epilepsy contributes to high morbidity among children and adolescents in developing countries. A quarter of all children with epilepsy will be resistant to anti-seizure medications (ASMs), with associated neurocognitive impairments and risk of higher mortality. This study aimed to estimate and characterize drug-resistant epilepsy (DRE) (defined as failure to achieve sustained remission after adequate trials of two tolerated and appropriately chosen ASMs) and its associated factors among children and adolescents with epilepsies attending the pediatric neurology clinic at Muhimbili National Hospital (MNH), Dar es Salaam Tanzania.

METHODS

This cross-sectional study was conducted from June 2020 to June 2021. Children with epilepsies and who had been treated with ASMs for at least 3 months were eligible for inclusion. Exclusion criteria included children whose caregivers denied consent and those who exhibited acute medical conditions necessitating admission on the scheduled visit day. Data on demographic characteristics, perinatal history, detailed history of the seizures semiology, drug history, magnetic resonance imaging (MRI), and electroencephalography (EEG) results were obtained from caregivers and medical records available during recruitment. Seizures and epilepsies were classified using the 2017 International League Against Epilepsy (ILAE) classification. Logistic regression was used to determine factors associated with DRE.

RESULTS

A total of 236 children and adolescents aged between 4 months and 15 years (Median age 72 months (IQR = 42-78)) were enrolled in this study. We found the proportion of DRE to be 14.8% in this cohort. Of the thirty-five patients with DRE, 60% had generalized epilepsy and almost 25% had a diagnosis of an epilepsy syndrome, the most common being Lennox-Gastaut syndrome (LGS). Structural abnormalities on brain MRI were seen in almost 80% of all patients with DRE, the most prevalent being cystic encephalomalacia, which was observed in 34% of patients. Patients using both ASMs and alternative therapies accounted for 9% of this cohort. The onset of seizures during the first month of life (aOR = 1.99; 95%CI 1.7-4.6; p = 0.031) and high initial seizure frequency (aOR = 3.6; 95%CI 1.6-8;p = 0.002) were found to be independently associated with DRE.

CONCLUSION

The proportion of DRE in Tanzania is high. Patients with neonatal onset seizures and high initial seizure frequency should be followed up closely to ensure early diagnosis of DRE.

[Safety of robot-assisted implantation of deep electrodes for invasive stereo-EEG monitoring]

Robot-assisted implantation of deep electrodes for stereo-EEG monitoring has become popular in recent years in patients with drug-resistant epilepsy. However, there are still few data on safety of this technique.

OBJECTIVE

To assess the incidence of complications in patients with drug-resistant epilepsy undergoing robot-assisted implantation of stereo-EEG electrodes.

MATERIAL AND METHODS

We retrospectively studied the results of implantation of stereo-EEG electrodes in 187 patients with drug-resistant epilepsy. All patients underwent non-invasive preoperative examination (video-EEG, MRI, PET, SPECT, MEG). In case of insufficient data, stereo-EEG monitoring was prescribed. We determined electrode insertion trajectory using a robotic station and MR images. Implantation of electrodes was carried out using a Rosa robot (Medtech, France). All patients underwent invasive EEG monitoring after implantation.

RESULTS

There were 11.25±3 electrodes per a patient. Implantation of one electrode took 7.5±4.9 min. Postoperative MRI revealed electrode malposition in 2.3% of cases. None was associated with complications. The complication rate per electrode was 0.6%. Complications affected stereo-EEG monitoring only in 3 cases (1.6%). The mortality rate was 0.5%. Bilateral implantation (p=0.005), insular (p=0.040) and occipital (p=0.045) deep electrode implantation were associated with lower incidence of complications. Longer duration of the procedure influenced the incidence of electrode placement in the lateral ventricle (p=0.028), and implantation in the frontal lobe was more often associated with epidural placement of electrodes (p=0.039).

CONCLUSION

Robot-assisted implantation of stereo-EEG electrodes is a safe procedure with minimal risk of complications. Rare electrode malposition does not usually affect invasive monitoring.

Increased Cyclic Adenosine Monophosphate Responsive Element is Closely Associated with the Pathogenesis of Drug-resistant Epilepsy

BACKGROUND

Drug-resistant epilepsy (DRE) is a refractory neurological disorder. There is ample evidence that suggest that γ-aminobutyric acid-a (GABAA) receptors could be one of the mechanisms responsible for the development of drug resistance in epilepsy. It is also known that the cAMP response element binding protein (CREB) plays a possible key role in the transcriptional regulation of GABAA.

OBJECTIVE

This study explores the role of CREB in the development of DRE and the effect of CREB on GABA-related receptors in DRE.

METHODS

The CREB expression was increased or decreased in the hippocampus of normal rats by lentiviral transfection, who then underwent the lithium-pilocarpine-induced epilepsy model. Phenobarbital (PB) sodium and carbamazepine (CBZ) were used to select a drug-resistant epileptic model. The expression levels of GABAA receptor α1, β2, and γ2 subunits and CREB protein were measured in the rat hippocampus by western blot and fluorescent quantitative PCR.

RESULTS

The frequency and duration of seizures increased in the overexpression group compared to that in the control group. In addition, the severity, frequency, and duration of seizures decreased in the group with decreased expression. The hippocampus analysis of the expression levels of the CREB protein and CREB mRNA yielded similar findings. Altering the CREB protein expression in the rat hippocampus could negatively regulate the expression and transcript levels of GABAA receptors α1, β2, and γ2, suggesting that CREB may serve as a potential target for the development of treatment protocols and drugs for epilepsy.

CONCLUSION

Our study shows that enhanced CREB expression promotes the development of DRE and negatively regulates GABAA receptor levels and that the inhibition of CREB expression may reduce the incidence of DRE.

Early prediction of drug-resistant epilepsy using clinical and EEG features based on convolutional neural network

OBJECTIVE

Machine learning utilization in electroencephalogram (EEG) analysis and epilepsy care is fast evolving. Thus, we aim to develop and validate two one-dimensional convolutional neural network (CNN) algorithms for predicting drug-resistant epilepsy (DRE) in patients with newly-diagnosed epilepsy based on EEG and clinical features.

METHODS

We included a total of 1010 EEG signal epochs and 15 clinical features from 101 patients with epilepsy. Each patient had 10 epochs of EEG signal data, with each signal recorded for 90 s. The ratio of development set and validation set was 80:20, and ten-fold cross validation was performed. First, a CNN algorithm was used to extract EEG features automatically. Then, Two one-dimensional CNNs were crafted.. Accuracy, specificity, precision, sensitivity, F1-score, kappa statistics, mean square error (MSE) and area under the curve (AUC) were calculated to evaluate the classifiers performance.

RESULTS

The clinical-EEG model showed good performance and clinical practical value, with the accuracy, specificity, precision, sensitivity, F1-score, kappa statistics, best MSE and AUC in test set were 0.99, 0.72, 0.82, 0.96, 0.89, 0.83, 32.00, 0.81, respectively, and the accuracy in validation set was 0.84. In the EEG model, the accuracy, specificity, precision, sensitivity, F1-score, kappa statistics, best MSE and AUC in test set were 0.99, 0.59, 0.82, 0.90, 0.86, 0.72, 181.76, 0.76, respectively, and the accuracy in validation set was 0.81.

CONCLUSION

We constructed a clinical-EEG model showed good potential for predicting DRE in patients with newly-diagnosed epilepsy, which could help identify patients at high risk of developing DRE at earlier stages.