Neurodevelopmental Effects of Antiepileptic Drugs

Epilepsy and childhood psychiatric disorders: a two-sample bidirectional Mendelian randomization study

BACKGROUND

Observational studies have indicated that psychiatric disorders are the most common comorbidities in pediatric epilepsy. However, the existence and direction of a causal relationship between the two remains controversial. This study aims to investigate the association between common childhood psychiatric disorders and epilepsy using a two-sample, bidirectional Mendelian randomization (MR) approach.

METHODS

Genetic instruments were obtained from the most recent and largest genome-wide association studies (GWAS), including datasets for epilepsy (N_case = 29,994, N_control = 52,538), attention deficit hyperactivity disorder (ADHD) (N_case = 38,691, N_control = 186,843), autism spectrum disorder (ASD) (N_case = 18,381, N_control = 27,969), and Tourette syndrome (TS) (N_case = 4,819, N_control = 9488). MR analyses were conducted using the inverse variance weighted (IVW) method, weighted median method, and MR-Egger regression.

RESULTS

No reliable evidence was found to suggest a causal effect of ADHD, ASD, or TS on epilepsy, nor was there any reliable evidence indicating that epilepsy increases the risk of these three psychiatric disorders. These findings remained consistent across various sensitivity analyses.

CONCLUSION

Although observational studies have highlighted a high comorbidity rate between pediatric epilepsy and psychiatric disorders like ADHD and ASD, the MR analysis did not confirm a causal relationship between them. This suggests that previous studies might have been influenced by confounding biases or other biases, potentially overestimating the true relationship. A deeper understanding of the mechanisms underlying these comorbidities is crucial for refining the treatment of pediatric epilepsy.

Alterations in spatiotemporal characteristics of dynamic networks in juvenile myoclonic epilepsy

BACKGROUND

Juvenile myoclonic epilepsy (JME) is characterized by altered patterns of brain functional connectivity (FC). However, the nature and extent of alterations in the spatiotemporal characteristics of dynamic FC in JME patients remain elusive. Dynamic networks effectively encapsulate temporal variations in brain imaging data, offering insights into brain network abnormalities and contributing to our understanding of the seizure mechanisms and origins.

METHODS

Resting-state functional magnetic resonance imaging (rs-fMRI) data were procured from 37 JME patients and 37 healthy counterparts. Forty-seven network nodes were identified by group-independent component analysis (ICA) to construct the dynamic network. Ultimately, patients' and controls' spatiotemporal characteristics, encompassing temporal clustering and variability, were contrasted at the whole-brain, large-scale network, and regional levels.

RESULTS

Our findings reveal a marked reduction in temporal clustering and an elevation in temporal variability in JME patients at the whole-brain echelon. Perturbations were notably pronounced in the default mode network (DMN) and visual network (VN) at the large-scale level. Nodes exhibiting anomalous were predominantly situated within the DMN and VN. Additionally, there was a significant correlation between the severity of JME symptoms and the temporal clustering of the VN.

CONCLUSIONS

Our findings suggest that excessive temporal changes in brain FC may affect the temporal structure of dynamic brain networks, leading to disturbances in brain function in patients with JME. The DMN and VN play an important role in the dynamics of brain networks in patients, and their abnormal spatiotemporal properties may underlie abnormal brain function in patients with JME in the early stages of the disease.

Association between neurodevelopmental outcomes and concomitant presence of NEC and IVH in extremely low birth weight infants

OBJECTIVE

To quantify the association between necrotizing enterocolitis (NEC) and neurodevelopmental disability (NDI) in extremely low birth weight (ELBW) infants with intraventricular hemorrhage (IVH).

STUDY DESIGN

ELBW survivors born 2011-2017 and evaluated at 16-26 months corrected age in the Vermont Oxford Network (VON) ELBW Follow-Up Project were included. Logistic regression determined the adjusted relative risk (aRR) of severe NDI in medical or surgical NEC compared to no NEC, stratified by severity of IVH.

RESULTS

Follow-up evaluation occurred in 5870 ELBW survivors. Compared to no NEC, medical NEC had no impact on NDI, regardless of IVH status. Surgical NEC increased risk of NDI in patients with no IVH (aRR 1.69; 95% CI 1.36-2.09), mild IVH (aRR 1.36;0.97-1.92), and severe IVH (aRR 1.35;1.13-1.60).

CONCLUSIONS

ELBW infants with surgical NEC carry increased risk of neurodevelopmental disability within each IVH severity stratum. These data describe the additive insult of surgical NEC and IVH on neurodevelopment, informing prognostic discussions and highlighting the need for preventative interventions.

Measuring Real-Time Medication Effects From Electroencephalography

PURPOSE

Evaluating the effects of antiseizure medication (ASM) on patients with epilepsy remains a slow and challenging process. Quantifiable noninvasive markers that are measurable in real-time and provide objective and useful information could guide clinical decision-making. We examined whether the effect of ASM on patients with epilepsy can be quantitatively measured in real-time from EEGs.

METHODS

This retrospective analysis was conducted on 67 patients in the long-term monitoring unit at Boston Children's Hospital. Two 30-second EEG segments were selected from each patient premedication and postmedication weaning for analysis. Nonlinear measures including entropy and recurrence quantitative analysis values were computed for each segment and compared before and after medication weaning.

RESULTS

Our study found that ASM effects on the brain were measurable by nonlinear recurrence quantitative analysis on EEGs. Highly significant differences ( P < 1e-11) were found in several nonlinear measures within the seizure zone in response to antiseizure medication. Moreover, the size of the medication effect correlated with a patient's seizure frequency, seizure localization, number of medications, and reported seizure frequency reduction on medication.

CONCLUSIONS

Our findings show the promise of digital biomarkers to measure medication effects and epileptogenicity.

Exposure to medication for neurological disease in pregnancy - time to consider the long-term implications?

A range of long-term neurological conditions may be diagnosed in young adulthood. These conditions are generally not curable, and most people need to take ongoing treatment for symptom control and/or disease modification. When chronic diseases are diagnosed before people have completed their families, there is a need to balance the potential benefits of treatment for the mother against potential risk(s) to the fetus from exposure to medications during pregnancy. Whilst available data regarding short-term fetal outcomes following treatment exposures during pregnancy is rapidly increasing, information regarding longer-term outcomes is more limited. The association of fetal exposure to valproate with serious long-term neurodevelopmental outcomes has highlighted the importance of capturing and evaluating long-term data. In this review we examine available evidence around the long-term effects of treatments used for the most common long-term neurological conditions diagnosed in early adulthood, namely epilepsy, migraine and neuroinflammatory disorders. We draw from existing literature across a range of diseases and discuss strategies to improve future knowledge.

Does Ketogenic Diet Used in Pregnancy Affect the Nervous System Development in Offspring?─FTIR Microspectroscopy Study

Anti-seizure medications used during pregnancy may have transient or long-lasting impact on the nervous system of the offspring. Therefore, there is a great need to search for alternative therapies for pregnant women suffering from seizures. One of the solutions may be the use of the ketogenic diet (KD), which has been successfully applied as a treatment of drug-resistant epilepsy in children and adults. However, the risks associated with the use of this dietary therapy during pregnancy are unknown and more investigation in this area is needed. To shed some light on this problem, we attempted to determine the potential abnormalities in brain biomolecular composition that may occur in the offspring after the prenatal exposure to KD. To achieve this, the female Wistar rats were, during pregnancy, fed with either ketogenic or standard laboratory diet, and for further studies, their male offspring at 2, 6, or 14 days of age were used. Fourier transform infrared microspectroscopy was applied for topographic and quantitative analysis of main biological macromolecules (proteins, lipids, compounds containing phosphate and carbonyl groups, and cholesterol) in brain samples. Performed chemical mapping and further semi-quantitative and statistical analysis showed that the use of the KD during pregnancy, in general, does not lead to the brain biochemical anomalies in 2 and 6 days old rats. The exception from this rule was increased relative (comparing to proteins) content of compounds containing phosphate groups in white matter and cortex of 2 days old rats exposed prenatally to KD. Greater number of abnormalities was found in brains of the 14 days old offspring of KD-fed mothers. They included the increase of the relative level of compounds containing carbonyl groups (in cortex as well as multiform and molecular cells of the hippocampal formation) as well as the decrease of the relative content of lipids and their structural changes (in white matter). What is more, the surface of the internal capsule (structure of the white matter) determined for this age group was smaller in animals subjected to prenatal KD exposure. The observed changes seem to arise from the elevated exposition to ketone bodies during a fetus life and the disturbance of lipid metabolism after prenatal exposure to the KD. These changes may be also associated with the processes of compensation of mother organism, which slowly began to make up for the deficiencies in carbohydrates postpartum.

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

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

Does maternal genetic liability to folate deficiency influence the risk of antiseizure medication-associated language impairment and autistic traits in children of women with epilepsy?

BACKGROUND

Prenatal exposure to antiseizure medication (ASM) may lead to low plasma folate concentrations and is associated with impaired neurodevelopment.

OBJECTIVE

To examine whether maternal genetic liability to folate deficiency interacts with ASM-associated risk of language impairment and autistic traits in children of women with epilepsy.

METHODS

We included children of women with and without epilepsy and with available genetic data enrolled in the Norwegian Mother, Father, and Child Cohort Study (MoBa). Information on ASM use, folic acid supplement use and dose, dietary folate intake, child autistic traits, and child language impairment was obtained from parent-reported questionnaires. Using logistic regression, we examined the interaction between prenatal ASM exposure and maternal genetic liability to folate deficiency expressed as polygenic risk score (PRS) of low folate concentrations or maternal rs1801133 genotype (CC or CT/TT) on risk of language impairment or autistic traits.

RESULTS

We included 96 children of women with ASM-treated epilepsy, 131 children of women with ASM-untreated epilepsy, and 37,249 children of women without epilepsy. The PRS of low folate concentrations or the maternal rs1801133 genotype did not interact with the ASM-associated risk of language impairment or autistic traits in ASM-exposed children of women with epilepsy compared to ASM-unexposed children aged 1.5-8 years. ASM-exposed children had increased risk of adverse neurodevelopment regardless of maternal rs1801133 genotype (adjusted odds ratio (aOR) for language impairment age 8 years was 2.88 (95% confidence interval (CI) 1.00-8.26) if CC and aOR 2.88 (CI 1.10-7.53) if CT/TT genotypes). In children of women without epilepsy aged 3 years, those with maternal rs1801133 CT/TT compared to CC genotype had increased risk of language impairment (aOR 1.18, CI 1.05-1.34).

CONCLUSIONS

In this cohort of pregnant women reporting widespread use of folic acid supplements, maternal genetic liability to folate deficiency did not significantly influence the ASM-associated risk of impaired neurodevelopment.

Clinical Outcome Data of Children Treated with Cannabis-Based Medicinal Products for Treatment Resistant Epilepsy - Analysis from the UK Medical Cannabis Registry

BACKGROUND

 There is a paucity of high-quality evidence of the efficacy and safety of cannabis-based medicinal products in treatment of treatment-resistant epilepsy (TRE) in children.

METHODS

 A case series of children (<18 years old) with TRE from the UK Medical Cannabis Registry was analyzed. Primary outcomes were ≥50% reduction in seizure frequency, changes in the Impact of Pediatric Epilepsy Score (IPES), and incidence of adverse events.

RESULTS

 Thirty-five patients were included in the analysis. Patients were prescribed during their treatment with the following: CBD isolate oils (n = 19), CBD broad-spectrum oils (n = 17), and CBD/Δ⁹-THC combination therapy (n = 17). Twenty-three (65.7%) patients achieved a ≥50% reduction in seizure frequency. 94.1% (n = 16) of patients treated with CBD and Δ⁹-THC observed a ≥50% reduction in seizure frequency compared to 31.6% (n = 6) and 17.6% (n = 3) of patients treated with CBD isolates and broad-spectrum CBD products, respectively (p< 0.001). Twenty-six (74.3%) adverse events were reported by 16 patients (45.7%). The majority of these were mild (n = 12; 34.2%) and moderate (n = 10; 28.6%).

CONCLUSION

 The results of this study demonstrate a positive signal of improved seizure frequency in children treated with Cannabis-based medicinal products (CBMPs) for TRE. Moreover, the results suggest that CBMPs are well-tolerated in the short term. The limitations mean causation cannot be determined in this open-label, case series.

Effects of Maternal Use of Antiseizure Medications on Child Development

Most children born to women with epilepsy (WWE) are normal, but have increased risks for malformations and poor neuropsychological outcomes. Antiseizure medications (ASMs) are among the most commonly prescribed teratogenic medications in women of childbearing age. However, WWE typically cannot avoid using ASMs during pregnancy. Teratogenic risks vary across ASMs. Valproate poses a special risk for anatomic and behavioral teratogenic risks compared with other ASMs. The risks for many ASMs remain uncertain. Women of childbearing potential taking ASMs should be taking folic acid. Breastfeeding while taking ASMs seems safe. WWE should receive informed consent outlining risks before conception.

The Role of Epigenetics in the Pathogenesis and Potential Treatment of Attention Deficit Hyperactivity Disorder

There is increasing evidence that dysregulated epigenetic mechanisms of gene expression are involved in the pathogenesis of attention deficit hyperactivity disorder (ADHD). This review presents a comprehensive summary of the current state of research on the role of epigenetics in the pathogenesis of ADHD. The potential role of epigenetic drugs in the treatment of ADHD is also reviewed. Several studies suggest that there are epigenetic abnormalities in preclinical models of ADHD and in ADHD patients. Regarding DNA methylation, many studies have reported DNA hypermethylation. There is evidence that there is increased histone deacetylation in ADHD patients. Abnormalities in the expression of microRNAs (miRNAs) in ADHD patients have also been found. Some currently used drugs for treating ADHD, in addition to their more well-established mechanisms of action, have been shown to alter epigenetic mechanisms of gene expression. Clinical trials of epigenetic drugs in patients with ADHD report favorable results. These data suggest that abnormal epigenetic mechanisms of gene expression may be involved in the pathogenesis of ADHD. Drugs acting on epigenetic mechanisms may be a potential new class of drugs for treating ADHD.

Low reliability of DNA methylation across Illumina Infinium platforms in cord blood: implications for replication studies and meta-analyses of prenatal exposures

Background

There is an increasing interest in the role of epigenetics in epidemiology, but the emerging research field faces several critical biological and technical challenges. In particular, recent studies have shown poor correlation of measured DNA methylation (DNAm) levels within and across Illumina Infinium platforms in various tissues. In this study, we have investigated concordance between 450 k and EPIC Infinium platforms in cord blood. We could not replicate our previous findings on the association of prenatal paracetamol exposure with cord blood DNAm, which prompted an investigation of cross-platform DNAm differences.

Results

This study is based on two DNAm data sets from cord blood samples selected from the Norwegian Mother, Father and Child Cohort Study (MoBa). DNAm of one data set was measured using the 450 k platform and the other data set was measured using the EPIC platform. Initial analyses of the EPIC data could not replicate any of our previous significant findings in the 450 k data on associations between prenatal paracetamol exposure and cord blood DNAm. A subset of the samples (n = 17) was included in both data sets, which enabled analyses of technical sources potentially contributing to the negative replication. Analyses of these 17 samples with repeated measurements revealed high per-sample correlations (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\stackrel{\mathrm{-}}{\text{R}}\hspace{0.17em}\approx$$\end{document}R-≈ 0.99), but low per-CpG correlations (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\stackrel{\mathrm{-}}{\text{R}}$$\end{document}R- ≈ 0.24) between the platforms. 1.7% of the CpGs exhibited a mean DNAm difference across platforms > 0.1. Furthermore, only 26.7% of the CpGs exhibited a moderate or better cross-platform reliability (intra-class correlation coefficient ≥ 0.5).

Conclusion

The observations of low cross-platform probe correlation and reliability corroborate previous reports in other tissues. Our study cannot determine the origin of the differences between platforms. Nevertheless, it emulates the setting in studies using data from multiple Infinium platforms, often analysed several years apart. Therefore, the findings may have important implications for future epigenome-wide association studies (EWASs), in replication, meta-analyses and longitudinal studies. Cognisance and transparency of the challenges related to cross-platform studies may enhance the interpretation, replicability and validity of EWAS results both in cord blood and other tissues, ultimately improving the clinical relevance of epigenetic epidemiology.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13148-022-01299-3.

Plasma unmetabolized folic acid in pregnancy and risk of autistic traits and language impairment in antiseizure medication-exposed children of women with epilepsy

BACKGROUND

Fetal exposure to unmetabolized folic acid (UMFA) during pregnancy may be associated with adverse neurodevelopment. Antiseizure medication (ASM) may interact with folate metabolism. Women with epilepsy using ASM are often recommended high-dose folic acid supplement use during pregnancy.

OBJECTIVES

The aim was to determine the association between UMFA concentrations in pregnant women with epilepsy using ASM and risk of autistic traits or language impairment in their children aged 1.5-8 y.

METHODS

We included children of women with epilepsy using ASM and with plasma UMFA measurement enrolled in the Norwegian Mother, Father, and Child Cohort Study (MoBa). Data on ASM use, folic acid supplement use, autistic traits, and language impairment were obtained from parent-reported questionnaires during pregnancy and when the child was 1.5, 3, 5, and 8 y old. Plasma UMFA concentrations were measured during gestational weeks 17-19.

RESULTS

A total of 227 ASM-exposed children of 203 women with epilepsy were included. Response rates at ages 1.5, 3, 5, and 8 y were 67% (n = 151), 54% (n = 122), 36% (n = 82), and 37% (n = 85), respectively. For 208 (94%) children, the mother reported intake of folic acid supplement. There was no association between UMFA concentrations and autistic traits score in the adjusted multiple regression analyses at age 3 y (unstandardized B: -0.01; 95% CI: -0.03, 0.004) or 8 y (unstandardized B: 0.01; 95% CI: -0.02, 0.03). Children exposed to UMFA had no increased risk of autistic traits at age 3 y [adjusted OR (aOR): 0.98; 95% CI: 0.2, 4.2] or 8 y (aOR: 0.1; 95% CI: 0.01, 1.4) compared with unexposed children. We found no association between UMFA concentrations and language impairment in children aged 1.5-8 y.

CONCLUSIONS

Our findings do not support any adverse neurodevelopmental effects of UMFA exposure in utero in children of women with epilepsy using ASM.

Vitamin B status and association with antiseizure medication in pregnant women with epilepsy

OBJECTIVE

Antiseizure medication (ASM) use interacts with vitamin B status in nonpregnant epilepsy populations. We aimed to examine the association between ASM and vitamin B status in pregnant women with epilepsy.

METHODS

We performed a cross-sectional study of pregnancies in women with epilepsy enrolled in the Norwegian Mother, Father and Child Cohort Study from 1999 to 2008. Data on ASM and vitamin supplement use were collected from questionnaires. We analyzed maternal plasma concentrations of ASM and metabolites of folate, including unmetabolized folic acid (UMFA), riboflavin (vitamin B2), pyridoxine (vitamin B6), and niacin (vitamin B3) during gestational weeks 17-19.

RESULTS

We included 227 singleton pregnancies exposed to ASM with available plasma samples (median maternal age 29 years, range 18 to 41 years). From the preconception period to gestational week 20, any supplement of folic acid was reported in 208 of pregnancies (94%), riboflavin in 72 (33%), pyridoxine in 77 (35%), and niacin in 45 (20%). High ASM concentrations correlated with high concentrations of UMFA and inactive folate metabolites, and with low concentrations of riboflavin and metabolically active pyridoxine. There was no association between ASM and niacin status.

SIGNIFICANCE

ASM concentrations during pregnancy were associated with vitamin B status in pregnant women with epilepsy. Additional studies are needed to determine the clinical impact of these findings, and to define the optimal vitamin doses that should be recommended to improve pregnancy outcomes.

Impact of In Utero Exposure to Antiepileptic Drugs on Neonatal Brain Function

In utero brain development underpins brain health across the lifespan but is vulnerable to physiological and pharmacological perturbation. Here, we show that antiepileptic medication during pregnancy impacts on cortical activity during neonatal sleep, a potent indicator of newborn brain health. These effects are evident in frequency-specific functional brain networks and carry prognostic information for later neurodevelopment. Notably, such effects differ between different antiepileptic drugs that suggest neurodevelopmental adversity from exposure to antiepileptic drugs and not maternal epilepsy per se. This work provides translatable bedside metrics of brain health that are sensitive to the effects of antiepileptic drugs on postnatal neurodevelopment and carry direct prognostic value.

Neurocognitive Effects of Antiseizure Medications in Children and Adolescents with Epilepsy

Impairments in cognition are common in epilepsy and may be caused or exacerbated by antiseizure medications (ASMs). Positive effects on cognition may also be seen with some ASMs. Cognitive outcomes are of particular concern in children who may be at an increased risk of cognitive adverse effects of treatment. A comprehensive literature search was conducted in PubMed in order to evaluate the evidence for cognitive changes associated with treatment with ASMs in paediatric epilepsy patients. The ASMs considered were those in the current edition of the British National Formulary (BNF). For most ASMs, remarkably few studies providing robust data on cognitive effects in paediatric patients were identified. The available evidence suggests cognitive impairments may be associated with treatment with phenobarbital. Topiramate and phenytoin are also associated with negative effects on cognition, in particular word-finding difficulties and other language deficits with topiramate, but there are few data available specifically on children. Lamotrigine, levetiracetam and fenfluramine are associated with improvements in some cognitive domains, although it is unclear whether these effects are directly attributable to the medications or are a result of improvements in seizures. Neutral effects on cognition (no substantial evidence of worsening) were suggested for carbamazepine, everolimus, lacosamide, oxcarbazepine, perampanel and valproate. There is limited data for cannabidiol, clobazam, eslicarbazepine acetate, ethosuximide, rufinamide, vigabatrin and zonisamide, although the available evidence suggests these drugs are not associated with severe cognitive impairment. There was too little information to reach conclusions about the effects of brivaracetam, felbamate, gabapentin, pregabalin, retigabine, stiripentol or tiagabine.

Epilepsy and pregnancy: What should the neurologists do?

Epilepsy is one of the most common chronic disorders affecting women of childbearing age. Unfortunately, many women with epilepsy (WWE) still report not receiving key information about pregnancy. They obviously need information about epilepsy and pregnancy prior to conception with a particular emphasis on effective birth control (i.e. contraception), necessity to plan pregnancy, antiepileptic drugs optimization, and folate supplementation. The risks associated with use of antiepileptic drugs during pregnancy have to be balanced against fetal and maternal risks associated with uncontrolled seizures. This report reviews evidence-based counseling and management strategies concerning maternal and fetal risks associated with seizures, teratogenic risks associated with antiepileptic drug exposure with a special emphasis on developmental and behavioural outcomes of children exposed to intra utero antiepileptic drugs.

The Pharmacology and Clinical Efficacy of Antiseizure Medications: From Bromide Salts to Cenobamate and Beyond

Epilepsy is one of the most common and disabling chronic neurological disorders. Antiseizure medications (ASMs), previously referred to as anticonvulsant or antiepileptic drugs, are the mainstay of symptomatic epilepsy treatment. Epilepsy is a multifaceted complex disease and so is its treatment. Currently, about 30 ASMs are available for epilepsy therapy. Furthermore, several ASMs are approved therapies in nonepileptic conditions, including neuropathic pain, migraine, bipolar disorder, and generalized anxiety disorder. Because of this wide spectrum of therapeutic activity, ASMs are among the most often prescribed centrally active agents. Most ASMs act by modulation of voltage-gated ion channels; by enhancement of gamma aminobutyric acid-mediated inhibition; through interactions with elements of the synaptic release machinery; by blockade of ionotropic glutamate receptors; or by combinations of these mechanisms. Because of differences in their mechanisms of action, most ASMs do not suppress all types of seizures, so appropriate treatment choices are important. The goal of epilepsy therapy is the complete elimination of seizures; however, this is not achievable in about one-third of patients. Both in vivo and in vitro models of seizures and epilepsy are used to discover ASMs that are more effective in patients with continued drug-resistant seizures. Furthermore, therapies that are specific to epilepsy etiology are being developed. Currently, ~ 30 new compounds with diverse antiseizure mechanisms are in the preclinical or clinical drug development pipeline. Moreover, therapies with potential antiepileptogenic or disease-modifying effects are in preclinical and clinical development. Overall, the world of epilepsy therapy development is changing and evolving in many exciting and important ways. However, while new epilepsy therapies are developed, knowledge of the pharmacokinetics, antiseizure efficacy and spectrum, and adverse effect profiles of currently used ASMs is an essential component of treating epilepsy successfully and maintaining a high quality of life for every patient, particularly those receiving polypharmacy for drug-resistant seizures.

Seizure mimics in children: An age-based approach

BACKGROUND

In order to distinguish seizure mimics from seizures in children it is important to clarify the event duration, frequency, semiology, and any precipitating factors.

METHODOLOGY

This review provides a succinct and up-to-date overview aimed at general and subspecialty non-neurologist pediatric and adolescent health care providers to help guide a diagnostic approach when a child presents with paroxysmal events of unclear etiology.

RESULTS

In many cases, seizure mimics are consistently triggered by an event, location, or emotion, and often resolve with distraction or tactile stimulation. Suspicion should be raised for seizures when events occur out of deep sleep, there is a loss of consciousness with the event, movements are not suppressible, and there is a period of fatigue afterword (minutes to hours). Further, a past medical history of developmental delay (e.g. autism), developmental regression, or neurologic injury increases patients' risk for seizures.

CONCLUSIONS

Common seizure mimics are highlighted in the age group in which they are most prevalent.

Association of Prenatal Exposure to Valproate and Other Antiepileptic Drugs With Intellectual Disability and Delayed Childhood Milestones

Importance

There is concern about neurodevelopmental outcomes associated with prenatal exposure to valproate and other antiepileptic drugs (AEDs) among children of mothers with or without epilepsy.

Objective

To study the risk of intellectual disability and delayed development in childhood milestones among children of women who used valproate or other AEDs during pregnancy.

Design, Setting, and Participants

This population-based cohort study analyzed information on use of AEDs from the Danish National Prescription Registry and register diagnoses from the Danish Psychiatric Central Research Register and Danish National Patient Registry. The study included all live-born singletons in Denmark from January 1, 1997, to December 31, 2011. Data were analyzed in April 2020.

Exposures

Prenatal exposure to maternal valproate and other AEDs.

Main Outcomes and Measures

The main measures were adjusted Cox regression estimates of hazard ratios (aHRs) for intellectual disability and a combined outcome of intellectual disability with delayed childhood milestones.

Results

A total of 913 302 children (468 708 [51.3%] boys; mean [SD] age, 10.3 [4.4] years and median [interquartile range] age, 10.1 [6.5-14.0] years at final follow-up) were identified and contributed more than 10.2 million person-years of observation, including 580 children exposed to valproate (302 [51.3%] boys). At end of follow-up, 6958 children (0.8%) were identified as having intellectual disability and 14 967 children (1.6%) were identified as having intellectual disability with delayed childhood milestones. Compared with offspring not exposed to valproate prenatally, offspring of women who used valproate during pregnancy had increased risk of intellectual disability (aHR, 4.48; 95% CI, 2.97-6.76) and intellectual disability with delayed childhood milestones (aHR, 6.07; 95% CI, 4.67-7.89). Among mothers with epilepsy, offspring exposed prenatally to valproate had increased risk of intellectual disability (aHR, 1.95; 95% CI, 1.21-3.14) and intellectual disability with delayed childhood milestones (aHR, 3.07; 95% CI, 2.24-4.20) compared with offspring without prenatal exposure. Compared with offspring without prenatal exposure to AEDs, increased risk of intellectual disability was identified in children with prenatal exposure to maternal monotherapy use of carbamazepine (aHR, 3.84; 95% CI, 2.32-6.38), clonazepam (aHR, 2.41; 95% CI, 1.09-5.35), and oxcarbazepine (aHR, 3.70; 95% CI, 2.11-6.51) but not lamotrigine (aHR, 1.33; 95% CI, 0.71-2.48).

Conclusions and Relevance

These findings suggest that prenatal exposure to valproate was associated with increased risk of intellectual disability and delayed childhood milestones. Statistically significant associations were also found for prenatal exposure to other AEDs. These findings suggest that women of childbearing potential may need to be counseled on use of AEDs.

Why do neonates receive antiseizure medications?

BACKGROUND

Continuous conventional video-electroencephalography (cVEEG), the gold standard, is not routinely available for monitoring neonatal seizures in Australia. Therefore, seizures are monitored with clinical observation and amplitude-integrated electroencephalography (aEEG), which may result in under- or over-treatment with antiseizure medications (ASMs). We aimed to investigate ASM usage and its relation to the "cVEEG-confirmed seizures" (cVEEG seizures) in the at-risk infants admitted to a tertiary referral neonatal intensive care unit (NICU).

METHODS

The study was a part of a diagnostic study comparing cVEEG with aEEG for the detection of neonatal seizures. Thirty-six infants ≥35 weeks gestational age and at risk of seizures and admitted to NICU were recruited after informed parental consent. The infants were monitored and treated with ASMs based on clinical observation and aEEG findings. A simultaneous cVEEG, not available for clinical decision making, was recorded for 24-h and interpreted at a later date. Data regarding ASM usage and seizure burden on cVEEG were collected. Spearman's Rho coefficient was used to assess the correlation between the number of doses of ASMs administered and seizure burden on cVEEG.

RESULTS

cVEEG recordings of 35 infants were available for analysis. The gestational age of the infants ranged from 36 to 42 weeks, and the most common diagnosis was hypoxic-ischemic encephalopathy. Twelve infants received ASMs during the 24-h study period, of which five (42%) did not have cVEEG seizures. Maximum cVEEG seizure burden was 8.3 h, and maximum number of ASMs used was three. The correlation between the number of doses of ASMs administered in an infant and the seizure burden on cVEEG was low (Spearman's Rho: 0.44; p = .148).

CONCLUSION

Treatment of neonatal seizures based on clinical observation and aEEG, without cVEEG, results in unnecessary or inadequate exposure to ASMs for many infants.

An update on maternal medication-related embryopathies

There is a general perception that any exposure to medication during pregnancy poses a potential risk to the fetus. Most available data about teratogenic drugs is derived from animal studies, case reports, or cohort studies. As a result, counseling women and their partners about the safety of drugs during pregnancy can be difficult due to limited information about efficacy, pharmacokinetics, and teratogenicity of some drugs. However, this should always be done in the context of weighing up potential teratogenic risks with the perinatal risks of an untreated medical or psychiatric condition. Ideally, this counseling should occur prior to a planned pregnancy so that medications and treatment of chronic medical conditions can be optimized. It is important that clinicians providing antenatal care are able to confidently manage women including utilizing appropriate resources. This paper aims at reviewing a selected (non-exhaustive) list of the most commonly prescribed medications considered significant human teratogens and provides recommendations for pre-conception and antenatal counseling.

Inter-rater reliability of amplitude-integrated EEG for the detection of neonatal seizures

BACKGROUND

Amplitude-integrated electroencephalogram (aEEG) is being used increasingly for seizure detection in neonates. However, data regarding inter-rater reliability among neonatologists for the use of aEEG for the detection of neonatal seizures is lacking.

METHODS

Term and late-preterm infants at risk of seizures were monitored simultaneously with 24-h video-electroencephalography (vEEG) and aEEG. vEEG was interpreted by an experienced neurologist. Five neonatologists with experience in aEEG interpretation from four different neonatal units interpreted aEEG recordings independently. The Brennan and Prediger kappa coefficient and Intra-class Correlation Coefficients (ICC) were used to assess inter-rater reliability between the neonatologists.

RESULTS

Thirty-five infants at risk of seizure with gestational age at birth 35-42 weeks were recruited for the study after informed parental consent. vEEG detected seizures in seven infants with a total of 169 individual seizure episodes. Neonatologists detected seizures in 10 to 15 infants on aEEG. The sensitivities for the detection of individual seizures by neonatologists ranged from 18% to 38%. The inter-rater reliability for detection of: individual seizure was "fair" (kappa = 0.37; 95% CI: 0.32-0.42), infant with seizure was "moderate" (kappa = 0.60; 95% CI: 0.44-0.75), duration of individual seizure (ICC: 0.22; 95% CI: 0.18-0.28) and total duration of seizures in an infant (ICC: 0.46; 95% CI: 0.30-0.63) was "poor". The neonatologists missed 77-90% of the duration of seizures.

CONCLUSION

The inter-rater reliability of aEEG for the detection of neonatal seizures was suboptimal. Even when interpreted by experienced and trained clinicians, seizure detection with aEEG has limitations and can miss large number and duration of seizures.

Remarkable effect of transdermal nicotine in children with CHRNA4-related autosomal dominant sleep-related hypermotor epilepsy

OBJECTIVE

Autosomal dominant sleep-related hypermotor epilepsy (ADSHE) is characterized by hypermotor seizures and may be caused by gain-of-function mutations affecting the nicotinic acetylcholine receptor (nAChR). Benefit from nicotine consumption has been reported in adult patients with this disorder. For the first time, the effect of transdermal nicotine is evaluated in children.

METHODS

Transdermal nicotine was applied to three boys, two aged 10 years (7 mg/24 h) and one six years (3.5 mg/24 h). Autosomal dominant sleep-related hypermotor epilepsy was caused by the p.S280F-CHRNA4 (cholinergic receptor, nicotinic, alpha polypeptide 4) mutation. The children suffered from frequent, persistent nocturnal seizures and had developed educational and psychosocial problems. Seizure frequency and cognitive and behavioral parameters were assessed before and after treatment.

RESULTS

A striking seizure reduction was reported soon after treatment onset. Hypermotor seizures disappeared; only sporadic arousals, sometimes with minor motor elements, were observed. Psychometric testing documented improvement in cognitive domains such as visuospatial ability, processing speed, memory, and some areas of executive functions.

SIGNIFICANCE

Nicotine appears to be a mechanistic treatment for this specific disorder, probably because of desensitization of the mutated receptors. It may control seizures resistant to conventional drugs for epilepsy and impact socioeducational function in children. This mode of precision therapy should receive more attention and should be available to more patients with uncontrolled CHRNA4-related ADSHE across the age span.

Why we urgently need improved seizure and epilepsy therapies for children and neonates

In contrast to epilepsy in adolescents and adults, neonatal seizures and early onset epilepsy poses unique challenges with significant repercussion for treatment choices. Most importantly, high seizure burden and epileptic encephalopathy are associated with developmental, behavioural and cognitive problems. The causes are multifactorial and include etiology, seizure burden, epileptic encephalopathy, but also antiseizure medication. In contrast to adults and older children only very few drugs have been licenced for infants and neonates, and after a long delay. Very recently, extrapolation of adult data has become possible as a path to speed up drug development for younger children but this is not necessarily possible for infants and neonates. With the advances in understanding the molecular basis of many epilepsies, targeted therapies become available, for example for KCNQ2 mutation related epilepsies, Dravet syndrome or tuberous sclerosis complex. Drug trials in neonates are particularly challenging because of their inconspicuous clinical presentation, the need for continuous EEG monitoring, high co-morbidity, and poor response to antiepileptic drugs. There is an urgent need for development of new drugs, evaluation of safety and efficacy of current antiseizure drugs, as well as for national policies and guidelines for the management of seizures and epilepsy in neonates and infants. This article is part of the special issue entitled 'New Epilepsy Therapies for the 21st Century - From Antiseizure Drugs to Prevention, Modification and Cure of Epilepsy'.

Enhancing effect of aerobic training on learning and memory performance in rats after long-term treatment with Lacosamide via BDNF-TrkB signaling pathway

Aerobic training has a neuroprotective effect, reduces the risk of developing neurodegenerative diseases and facilitates functional recovery. The present study assesses the effect of aerobic training on cognitive functions, hippocampal BDNF/TrkB ligand receptor system expression and serum levels of BDNF and corticosterone in intact rats after chronic treatment with Lacosamide (LCM). Male Wistar rats were randomly divided into two groups. One group was exercised on a treadmill (Ex) and the other one was sedentary (Sed). Half of the rats from each group received saline (veh) while the other half - LCM. The rats underwent a month-long training and LCM treatment before being subjected to one active and two passive avoidance tests. Both trained groups increased significantly the number of avoidances compared with the sedentary animals during the learning session and on memory retention tests, while the number of avoidances of the LCM-treated rats was significantly lower in comparison with the saline-treated animals. Both passive avoidance tests revealed that trained animals spent more time in the lighted compartment or caused longer stay on the platform than did the sedentary rats during acquisition and short- and long-term memory retention tests. Aerobic training increased BDNF and TrkB hippocampal immunoreactivity. We found no significant difference between BDNF serum levels but corticosterone levels of the Sed-LCM rats were lower than those of the Sed-veh animals. Our results show that aerobic training increases the hippocampal BDNF/TrkB expression suggesting a role in preventing the negative effect of Lacosamide on cognitive functions in rats.

Why do some women with epilepsy use valproic acid despite current guidelines? A single-center cohort study

OBJECTIVE

Current guidelines and regulations strongly discourage the use of valproic acid (VPA) in women of childbearing age because of the risk of congenital malformations and neurodevelopmental disability in children exposed to VPA in utero. Our goal was to establish the reasons for continued use of VPA in a cohort of women with epilepsy (WWE) and to characterize the subgroup of WWE who do not consent to withdraw VPA despite potential risks.

MATERIAL AND METHODS

The study included consecutive adult premenopausal WWE who visited an outpatient epilepsy clinic between April 2017 and March 2018. Data on demographics (age, age at onset of epilepsy), characteristics of epilepsy (types and frequency of seizures), and its treatment were collected from medical records and seizure diaries. All WWE taking VPA were regularly informed about VPA-related risks and had the opportunity to discuss the withdrawal of VPA.

RESULTS

The study involved 353 WWE (mean age: 31.7 years). Focal epilepsy was diagnosed in 244 (69.1%) patients; 180 (51.0%) women had no seizures during last 12 months before the study visit, and 228 patients (64.6%) were on monotherapy. A total of 146 (41.3%) patients used VPA in the past, and 98 (27.8%) never used VPA. Of women who were currently on VPA (n = 109, 30.9%), 30 had concurrent severe disabilities that would make future pregnancy extremely unlikely, in further 15 patients, VPA was recommenced because of failure of alternative treatment and 64 women did not accept the plan of VPA withdrawal. Women currently on VPA were more likely to have genetic generalized epilepsy and to be on monotherapy (both p ≪ 0.001). Among 64 WWE who decided to continue therapy with VPA, 35 (55.5%) had generalized epilepsy and 35 (55.5%) were in remission, 27 (42.2%) had at least one child, 9 (14.1%) planned to have a child in the near future but only 15 (23.4%) used effective contraception.

CONCLUSION

Treatment with VPA is unavoidable in many WWE of childbearing age despite recent regulations. About 60% of WWE currently treated with VPA do not consent to withdraw VPA treatment after thorough consideration of potential risks and other 40% use VPA because pregnancy is highly unlikely and/or other treatments failed.

Perinatal outcome and healthcare resource utilization in the first year of life after antiepileptic exposure during pregnancy

Healthcare administrative databases of Italy's Lombardy Region were analyzed with the aim to assess perinatal outcomes and healthcare resource utilization during the first year of life in infants exposed to antiepileptic drugs (AEDs) during pregnancy. Drug prescriptions dispensed in the 12 months before delivery to women, who delivered between 2005 and 2011, were analyzed. Neonates were classified as cases if exposed to AEDs, and each case was randomly matched to seven controls. No significant differences were observed in the risk of congenital malformations between 526 cases and 3682 controls except for valproic acid (odds ratio (OR): 2.29; 95% confidence interval (CI): 1.24-4.22) where cases were more likely to be small for gestational age (χ² = 7.66; p = 0.006). Cases also had a higher probability than controls of needing at least one specialist visit in a child neuropsychiatry outpatient service (OR: 1.74; 95% CI: 1.22-2.49).

In utero exposure to antiepileptic drugs is associated with learning disabilities among offspring

OBJECTIVES

In utero exposure to antiepileptic drugs has previously been associated with adverse outcome among offspring, but evidence on longer term milestone development remains limited. We investigated the association between in utero exposure to antiepileptic drugs and learning disabilities in the first year of compulsory education among offspring and assessed which antiepileptic drugs carried the highest risk.

METHODS

This population-based case-cohort study used Danish nationwide register data from 2005 to 2008. Cases were offspring exposed to antiepileptic drugs in utero, and controls were unexposed offspring of mothers previously redeeming antiepileptic drug prescriptions. Offspring were followed from birth until the first year of compulsory education from 2011 to 2015. Learning disabilities were defined as mental retardation, specific developmental disorders, autism spectrum disorders, emotional/behavioural disorders or having special educational needs. Logistic regression was used to compute ORs with 95% CIs adjusted for potential confounding.

RESULTS

Of 117 475 incident singleton births, 636 cases and 434 controls were included (median age: 6.1 years, males: 55.7%). Learning disabilities were identified among 7.1% cases compared with 3.7% for controls. During any trimester, the adjusted OR of the association between in utero exposure to antiepileptic drugs and learning disabilities was 2.20 (95% CI 1.16 to 4.17). Among cases not exposed to polytherapy (n=556), in utero exposure to lamotrigine compared with another antiepileptic drug was associated with the lowest adjusted risk (OR 0.42, 95% CI 0.19 to 0.92), and valproate carried a higher risk (OR 4.67, 95% CI 1.73 to 12.59).

CONCLUSION

In utero exposure to antiepileptic drugs was significantly associated with learning disabilities among offspring. Lamotrigine should preferentially be considered over, for example, valproate if clinically feasible.

Effect of Ketogenic Diet on Motor Functions and Daily Living Activities of Children With Multidrug-Resistant Epilepsy: A Prospective Study

AIMS

To investigate the effect of ketogenic diet on motor function and daily living activities in children with epilepsy.

METHODS

A total of 62 children (median age 5.0 years) were enrolled. Motor function was assessed using the Gross Motor Function Measure (GMFM), and daily living activities and cognitive functions were assessed using the Functional Independence Measure (WeeFIM) before treatment and 3, 6, and 12 months after ketogenic diet treatment.

RESULTS

Significant improvement in total GMFM and WeeFIM scores ( P < .001) were found during the 12 months of ketogenic diet treatment. There was a positive correlation between total GMFM scores and WeeFIM scores at baseline (r= 0.792, P = .0001), and at 3 (r= 0.780, P = .0001), 6 (r= 0.744, P = .0001), and 12 months (r= 0.692, P = .0001) of treatment. Both the responder (50 patients, 80.7%) and nonresponder (12 patients, 19.3%) patient groups showed significantly higher GMFM and WeeFIM scores at 12 months of treatment compared to baseline values. A ≥50% reduction in seizure frequency was observed in 77.4%, 72.6%, and 80.7% of the patients after 3, 6, and 12 months of treatment, respectively.

CONCLUSION

Ketogenic diet treatment improves motor functions and daily living activities in children with epilepsy during the 12 months of treatment.

Latest clinical recommendations on valproate use for migraine prophylaxis in women of childbearing age: overview from European Medicines Agency and European Headache Federation

Migraine is a common and burdensome neurological condition which affects mainly female patients during their childbearing years. Valproate has been widely used for the prophylaxis of migraine attacks and is also included in the main European Guidelines. Previous (2014) European recommendations on limiting the use of valproate in women of childbearing age did not achieve their objective in terms of limiting the use of valproate in women of childbearing age and raising awareness regarding the hazardous effect of valproate to children exposed in utero. The teratogenic and foetotoxic effects of valproate are well documented, and more recent studies show that there is an even greater neurodevelopmental risk to children exposed to valproate in the womb. The latest 2018 European review from the European Medicines Agency, with the active participation of the European Headache Federation, concluded that not enough has been done to mitigate the risks associated with in utero exposure to valproate. The review called for more extensive restrictions to the conditions for prescribing, better public awareness, and a more effective education campaign in migrainous women.

Declining trend in valproate use in Finland among females of childbearing age in 2012-2016 - a nationwide registry-based outpatient study

BACKGROUND AND PURPOSE

Documented teratogenic effects of valproate (VPA) prompted restrictions of its use in females of childbearing age in 2014. We investigated possible annual changes in the outpatient use of VPA in Finland during 2008-2016 with a special focus on women.

METHODS

We identified all outpatients with VPA purchases between 2008 and 2016 categorizing users due to epilepsy, bipolar disorder or miscellaneous indications. Temporal trends in the annual prevalence rates of VPA use were estimated using Poisson regression analyses.

RESULTS

Between 2012 and 2016, the prevalence of VPA use among women aged 15-44 years decreased by 19%, from 50/10 000 to 40/10 000 (prevalence rate ratio, 0.81; 95% confidence intervals, 0.77-0.91; P < 0.001). The use of VPA due to epilepsy decreased significantly in females aged 15-24 and 25-34 years and that due to bipolar disorders decreased significantly in females aged 25-34 and 35-44 years. The use of VPA in the miscellaneous indication group decreased by 32% after 2014 in females aged 15-44 years and, most strikingly, by 56% among those aged 15-25 years. In women with epilepsy, the use of VPA increased among those over the age of 44 years.

CONCLUSIONS

The rates of female VPA users with childbearing potential have decreased in all three major indication groups in Finland during recent years, especially after the European Medicines Agency restrictions were published in 2014. However, it still remains open to question as to whether the practice of VPA use follows current guidelines. A special concern is the relatively high prevalence of off-label use of VPA in fertile-aged females.

Psychoactive drug exposure during breastfeeding: a critical need for preclinical behavioral testing

Breastfeeding women are excluded from clinical trials of psychoactive drugs because of ethical concerns. Animal testing, which often is predictive of adverse effects in humans, represents the only avenue available for assessing drug safety for human offspring exposed to drugs during lactation. I determined whether behavioral outcomes for children exposed during breastfeeding to antidepressants, anxiolytics, antipsychotics, anti-seizure medications, analgesics, sedatives, and marijuana can be predicted by rodent studies of offspring exposed to drugs during lactation. Animal data were available for only 10 of 80 CNS-active drugs canvassed. Behavioral deficits in adolescence or adulthood in rats and mice after various drug exposures during lactation included reductions in sexual behavior, increased anxiety, hyperactivity, and impaired learning and memory. Whether similar adverse effects will emerge in adulthood in children exposed to drugs during breastfeeding is unknown. Rodent research has the potential to forecast impairments in breastfed children long before information emerges from post-marketing reports and should be prioritized during preclinical drug evaluation by the FDA for new drugs and for drugs currently prescribed off-label for lactating women.