A Multicenter Training and Interrater Reliability Study of the BASED Score for Infantile Epileptic Spasms Syndrome.

PURPOSE: The best possible outcomes in infantile epileptic spasms syndrome require electroclinical remission; however, determining electrographic remission is not straightforward. Although the determination of hypsarrhythmia has inadequate interrater reliability (IRR), the Burden of AmplitudeS and Epileptiform Discharges (BASED) score has shown promise for the reliable interictal assessment of infantile epileptic spasms syndrome. Our aim was to develop a BASED training program and assess the IRR among learners. We hypothesized moderate or better IRR for the final BASED score and the presence or absence of epileptic encephalopathy (+/-EE). METHODS: Using a web-based application, 31 learners assessed 12 unmarked EEGs (length 1-6 hours) from children with infantile epileptic spasms syndrome. RESULTS: For all readers, the IRR was good for the final BASED score (intraclass correlation coefficient 0.86) and +/-EE (Marginal Multirater Kappa 0.63). For all readers, the IRR was fair to good for all individual BASED score elements. CONCLUSIONS: These findings support the use of our training program to quickly learn the BASED scoring method. The BASED score may be a valuable clinical and research tool. Given that the IRR for the determination of epileptic encephalopathy is not perfect, clinical acumen remains paramount. Additional experience with the BASED scoring technique among learners and advances in collaborative EEG evaluation platforms may improve IRR.

High Doses of ANA12 Improve Phenobarbital Efficacy in a Model of Neonatal Post-Ischemic Seizures.

Phenobarbital (PB) remains the first-line medication for neonatal seizures. Yet, seizures in many newborns, particularly those associated with perinatal ischemia, are resistant to PB. Previous animal studies have shown that in postnatal day P7 mice pups with ischemic stroke induced by unilateral carotid ligation, the tyrosine receptor kinase B (TrkB) antagonist ANA12 (N-[2-[[(hexahydro-2-oxo-1H-azepin-3-yl)amino]carbonyl]phenyl]-benzo[b]thiophene-2-carboxamide, 5 mg/kg) improved the efficacy of PB in reducing seizure occurrence. To meet optimal standards of effectiveness, a wider range of ANA12 doses must be tested. Here, using the unilateral carotid ligation model, we tested the effectiveness of higher doses of ANA12 (10 and 20 mg/kg) on the ability of PB to reduce seizure burden, ameliorate cell death (assessed by Fluoro-Jade staining), and affect neurodevelopment (righting reflex, negative geotaxis test, open field test). We found that a single dose of ANA12 (10 or 20 mg/kg) given 1 h after unilateral carotid ligation in P7 pups reduced seizure burden and neocortical and striatal neuron death without impairing developmental reflexes. In conclusion, ANA12 at a range of doses (10-20 mg/kg) enhanced PB effectiveness for the treatment of perinatal ischemia-related seizures, suggesting that this agent might be a clinically safe and effective adjunctive agent for the treatment of pharmacoresistant neonatal seizures.

Evaluating Injury Severity in Neonatal Encephalopathy Using Automated Quantitative Electroencephalography Analysis: A Pilot Study.

Quantitative analysis of electroencephalography (qEEG) is a potential source of biomarkers for neonatal encephalopathy (NE). However, prior studies using qEEG in NE were limited in their generalizability due to individualized techniques for calculating qEEG features or labor-intensive pre-selection of EEG data. We piloted a fully automated method using commercially available software to calculate the suppression ratio (SR), absolute delta power, and relative delta, theta, alpha, and beta power from EEG of neonates undergoing 72 h of therapeutic hypothermia (TH) for NE between April 20, 2018, and November 4, 2019. We investigated the association of qEEG with degree of encephalopathy (modified Sarnat score), severity of neuroimaging abnormalities following TH (National Institutes of Child Health and Development Neonatal Research Network [NICHD-NRN] score), and presence of seizures. Thirty out of 38 patients met inclusion criteria. A more severe modified Sarnat score was associated with higher SR during all phases of TH, lower absolute delta power during all phases except rewarming, and lower relative delta power during the last 24 h of TH. In 21 patients with neuroimaging data, a worse NICHD-NRN score was associated with higher SR, lower absolute delta power, and higher relative beta power during all phases. QEEG features were not significantly associated with the presence of seizures after correction for multiple comparisons. Our results are consistent with those of prior studies using qEEG in NE and support automated qEEG analysis as an accessible, generalizable method for generating biomarkers of NE and response to TH. Additionally, we found evidence of an immature relative frequency composition in neonates with more severe brain injury, suggesting that automated qEEG analysis may have a use in the assessment of brain maturity.

Neighborhood disadvantage and intellectual development in youth with epilepsy.

RATIONALE: Recent cross-sectional investigations have demonstrated an adverse impact of socioeconomic disadvantage on cognition and behavior in youth and adults with epilepsy. The goal of this study is to investigate the impact of disadvantage on prospective intellectual development in youth with epilepsy. METHOD: Participants were youth, aged 8-18 years, with recent onset epilepsy (n = 182) and healthy first-degree cousin controls (n = 106). The Wechsler Abbreviated Scale of Intelligence (WASI) was administered at baseline and 2 years later. The Neighborhood Atlas identified each family's Area Deprivation Index via state deciles and national percentiles. WASI data were analyzed by mixed group by time ANOVAs followed by regression analysis to identify other baseline predictors of time 2 outcomes. RESULTS: Youth with epilepsy demonstrated significant interactions between group and time for both verbal (F = 4.02, df = 1,215, p =.05) and nonverbal (F = 4.57, df = 1,215, p =.04) reasoning, demonstrating that disadvantage was associated with slower cognitive development compared to advantaged youth with epilepsy. Similar interactions were not observed for controls. CONCLUSIONS: In youth with new and recent onset epilepsies, neighborhood-level disadvantage is associated with a negative impact on the development of verbal and nonverbal reasoning skills.

Pearls & Oy-sters: Epilepsy Is a Key Feature of Pediatric-Onset Huntington Disease.

Pediatric-onset Huntington disease (PoHD) presents differently from adult-onset disease. Children typically exhibit regression in school performance, psychiatric features such as inattention, and oral motor dysfunction. Unlike adult-onset HD, in which seizures occur at approximately the rate of the general public, at least half of children with HD develop epilepsy, and seizures can be a presenting feature of PoHD. Here we present the case of a 10-year-old boy with a history of language delay, motor regression, oral motor dysfunction, and tremor who presented with a first lifetime seizure. Given a family history of Huntington disease in his father, PoHD was considered, and a pathogenic allele with 88 repeats was confirmed in the child. As symptoms progressed, history alone could not differentiate abnormal movements from seizures. Continuous video electroencephalography helped to demonstrate epileptic myoclonic jerks and guide treatment.

Interaction of hydrocortisone and illness severity on head growth in cohort of ELBW infants.

BACKGROUND: Extremely low birth weight (ELBW) infants comprise a fragile population at risk for neurodevelopmental disabilities (NDD). Systemic steroids were previously associated with NDD, but more recent studies suggest hydrocortisone (HCT) may improve survival without increasing NDD. However, the effects of HCT on head growth adjusted for illness severity during NICU hospitalization are unknown. Thus, we hypothesize that HCT will protect head growth, accounting for illness severity using a modified neonatal Sequential Organ Failure Assessment (M-nSOFA) score. METHODS: We conducted a retrospective study that included infants born at 23-29 weeks gestational age (GA) and < 1000 g. Our study included 73 infants, 41% of whom received HCT. RESULTS: We found negative correlations between growth parameters and age, similar between HCT and control patients. HCT-exposed infants had lower GA but similar normalized birth weights; HCT-exposed infants also had higher illness severity and longer lengths of hospital stay. We found an interaction between HCT exposure and illness severity on head growth, such that infants exposed to HCT had better head growth compared to those not exposed to HCT when adjusted for illness severity. CONCLUSION: These findings emphasize the importance of considering patient illness severity and suggest that HCT use may offer additional benefits not previously considered. IMPACT: This is the first study to assess the relationship between head growth and illness severity in extremely preterm infants with extremely low birth weights during their initial NICU hospitalization. Infants exposed to hydrocortisone (HCT) were overall more ill than those not exposed, yet HCT exposed infants had better preserved head growth relative to illness severity. Better understanding of the effects of HCT exposure on this vulnerable population will help guide more informed decisions on the relative risks and benefits for HCT use.

Increased propensity for infantile spasms and altered neocortical excitation-inhibition balance in a mouse model of down syndrome carrying human chromosome 21.

Children with Down syndrome (DS, trisomy of chromosome 21) have an increased risk of infantile spasms (IS). As an epileptic encephalopathy, IS may further impair cognitive function and exacerbate neurodevelopmental delays already present in children with DS. To investigate the pathophysiology of IS in DS, we induced IS-like epileptic spasms in a genetic mouse model of DS that carries human chromosome 21q, TcMAC21, the animal model most closely representing gene dosage imbalance in DS. Repetitive extensor/flexor spasms were induced by the GABAB receptor agonist γ-butyrolactone (GBL) and occurred predominantly in young TcMAC21 mice (85%) but also in some euploid mice (25%). During GBL application, background electroencephalographic (EEG) amplitude was reduced, and rhythmic, sharp-and-slow wave activity or high-amplitude burst (epileptiform) events emerged in both TcMAC21 and euploid mice. Spasms occurred only during EEG bursts, but not every burst was accompanied by a spasm. Electrophysiological experiments revealed that basic membrane properties (resting membrane potential, input resistance, action-potential threshold and amplitude, rheobase, input-output relationship) of layer V pyramidal neurons were not different between TcMAC21 mice and euploid controls. However, excitatory postsynaptic currents (EPSCs) evoked at various intensities were significantly larger in TcMAC21 mice than euploid controls, while inhibitory postsynaptic currents (IPSCs) were similar between the two groups, resulting in an increased excitation-inhibition (E-I) ratio. These data show that behavioral spasms with epileptic EEG activity can be induced in young TcMAC21 DS mice, providing proof-of-concept evidence for increased IS susceptibility in these DS mice. Our findings also show that basic membrane properties are similar in TcMAC21 and euploid mice, while the neocortical E-I balance is altered to favor increased excitation in TcMAC21 mice, which may predispose to IS generation.

Early Clinical Variables Associated With Refractory Convulsive Status Epilepticus in Children.

BACKGROUND AND OBJECTIVES: The objective of this study was to determine patient-specific factors known proximate to the presentation to emergency care associated with the development of refractory convulsive status epilepticus (RSE) in children. METHODS: An observational case-control study was conducted comparing pediatric patients (1 month-21 years) with convulsive SE whose seizures stopped after benzodiazepine (BZD) and a single second-line antiseizure medication (ASM) (responsive established status epilepticus [rESE]) with patients requiring more than a BZD and a single second-line ASM to stop their seizures (RSE). These subpopulations were obtained from the pediatric Status Epilepticus Research Group study cohort. We explored clinical variables that could be acquired early after presentation to emergency medical services with univariate analysis of the raw data. Variables with p < 0.1 were retained for univariable and multivariable regression analyses. Multivariable logistic regression models were fit to age-matched and sex-matched data to obtain variables associated with RSE. RESULTS: We compared data from a total of 595 episodes of pediatric SE. Univariate analysis demonstrated no differences in time to the first BZD (RSE 16 minutes [IQR 5-45]; rESE 18 minutes [IQR 6-44], p = 0.068). Time to second-line ASM was shorter in patients with RSE (RSE 65 minutes; rESE 70 minutes; p = 0.021). Both univariable and multivariable regression analyses revealed a family history of seizures (OR 0.37; 95% CI 0.20-0.70, p = 0.0022) or a prescription for rectal diazepam (OR 0.21; 95% CI 0.078-0.53, p = 0.0012) was associated with decreased odds of RSE. DISCUSSION: Time to initial BZD or second-line ASM was not associated with progression to RSE in our cohort of patients with rESE. A family history of seizures and a prescription for rectal diazepam were associated with a decreased likelihood of progression to RSE. Early attainment of these variables may help care for pediatric rESE in a more patient-tailored manner. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that patient and clinical factors may predict RSE in children with convulsive seizures.

2-Deoxy-D-glucose administration after seizures has disease-modifying effects on kindling progression.

2-deoxy-D-glucose (2DG) is a glucose analog and reversible inhibitor of glycolysis with anticonvulsant and antiepileptic effects in multiple seizure models. 2DG at a dose of 250 mg/kg intraperitoneally (IP) delays progression of repeated seizures evoked by kindling in rats when administered 30 min prior to twice daily kindling stimulation. As toxicological studies have demonstrated that repeated daily oral administration of 2DG at doses of 60-375 mg/kg/day in rats induces dose-dependent, reversible cardiac myocyte vacuolation, it was of interest to determine if 2DG also slowed kindling progression when administered at or below doses causing cardiac toxicity and at various time points after evoked seizures. We found that: (1) 2DG slowed kindling progression nearly 2-fold when administered at a dose of 37.5 mg/kg given IP 30 min prior to kindling stimulation, and (2) 2DG 37.5 mg/kg IP also slowed kindling progression when given immediately after, and for as long as 10 min after evoked (kindled) seizures. These observations suggest potential clinical usefulness of post-seizure administration of 2DG to reduce seizure clusters and long-term consequences of repeated seizures at human equivalent doses that are likely to be safe and well tolerated in patients.

Antiseizure effect of 2-deoxyglucose is not dependent on the presynaptic vacuole ATP pump or the somatic ATP-sensitive K+ channel.

Inhibition of glycolysis with 2-deoxyglucose (2-DG) produces antiseizure effects in brain slices and animal models, yet the mechanisms remain elusive. Here, we examined two glycolysis-derived ATP-associated mechanisms: vacuole ATP pump (V-ATPase) and ATP-sensitive K+ channel (KATP). Epileptiform bursts were generated in the CA3 area of hippocampal slices by 0 Mg2+ and 4-aminopyridine. 2-DG consistently abolished epileptiform bursts in the presence of pyruvate (to sustain tricarboxylic acid cycle for oxidative ATP production) at 30-33°C but not at room temperature (22°C). Under physiological conditions, 2-DG did not reduce the amplitude of evoked excitatory postsynaptic currents (EPSCs) or the paired-pulse ratio in CA3 neurons. During repetitive high-frequency (20 Hz, 20-50 pulses) stimulation, 2-DG did not accelerate the decline of EPSCs (i.e., depletion of transmitter release), even when preincubated with 8 mM K+ to enhance activity-dependent uptake of 2-DG. In addition, in 2-DG tetanic stimulation (200 Hz, 1 s) dramatically increased rather than diminished the occurrence of spontaneous EPSCs immediately after stimulation (i.e., no transmitter depletion). Moreover, a V-ATPase blocker (concanamycin) failed to block epileptiform bursts that were subsequently abolished by 2-DG. Furthermore, 2-DG did not induce detectable KATP current in hippocampal neurons. Finally, epileptiform bursts were not affected by either a KATP opener (diazoxide) or a KATP blocker (glibenclamide) but were blocked by 2-DG in the same slices. Altogether, these data suggest that 2-DG's antiseizure action is temperature dependent and achieved exclusively by inhibition of glycolysis and is not likely to be mediated by the two membrane-bound ATP-associated machinery mechanisms, V-ATPase and KATP.NEW & NOTEWORTHY Inhibition of glycolysis with 2-deoxyglucose (2-DG) represents a novel metabolic antiseizure approach, yet the mechanisms remain elusive. Here, we show that 2-DG's antiseizure action is both glycolysis and temperature dependent but not mediated by the vacuole ATP pump (V-ATPase) or ATP-sensitive K+ channel (KATP). Our data provide new insights to understand 2-DG's cellular mechanisms of action and, more broadly, neuronal metabolism and excitability.

Disadvantage and neurocognitive comorbidities in childhood idiopathic epilepsies.

OBJECTIVE: This study was undertaken to characterize the relationship between neighborhood disadvantage and cognitive function as well as clinical, sociodemographic, and family factors in children with new onset idiopathic epilepsy and healthy controls. METHODS: Research participants were 288 children aged 8-18 years with recent onset epilepsy (CWE; n = 182; mean age = 12.2 ± 3.2 years), healthy first-degree cousin controls (HC; n = 106; mean age = 12.5 ± 3.0), and one biological or adopted parent per child (n = 279). All participants were administered a comprehensive neuropsychological battery (reasoning, language, memory, executive function, motor function, and academic achievement). Family residential addresses were entered into the Neighborhood Atlas to determine each family's Area Deprivation Index (ADI), a metric used to quantify income, education, employment, and housing quality. A combination of parametric and nonparametric (χ2 ) tests examined the effect of ADI by group (epilepsy and controls) across cognitive, academic, clinical, and family factors. RESULTS: Disadvantage (ADI) was equally distributed between groups (p = .63). For CWE, high disadvantage was associated with lower overall intellectual quotient (IQ; p = .04), visual naming/expressive language (p = .03), phonemic (letter) fluency (p < .01), passive inattention (omission errors; p = .03), delayed verbal recall (p = .04), and dominant fine motor dexterity and speed (p < .01). Cognitive status of the HC group did not differ by level of disadvantage (p = .40). CWE exhibited greater academic difficulties in comparison to HC (p < .001), which were exacerbated by disadvantage in CWE (p = .02) but not HC (p < .05). High disadvantage was associated with a threefold risk for academic challenges prior to epilepsy onset (odds ratio = 3.31, p = .024). SIGNIFICANCE: Socioeconomic hardship (increased neighborhood disadvantage) exerts a significant adverse impact on the cognitive and academic status of youth with new and recent onset epilepsies, an impact that needs to be incorporated into etiological models of the neurobehavioral comorbidities of epilepsy.

Epilepsy and its neurobehavioral comorbidities: Insights gained from animal models.

It is well established that epilepsy is associated with numerous neurobehavioral comorbidities, with a bidirectional relationship; people with epilepsy have an increased incidence of depression, anxiety, learning and memory difficulties, and numerous other psychosocial challenges, and the occurrence of epilepsy is higher in individuals with those comorbidities. Although the cause-and-effect relationship is uncertain, a fuller understanding of the mechanisms of comorbidities within the epilepsies could lead to improved therapeutics. Here, we review recent data on epilepsy and its neurobehavioral comorbidities, discussing mainly rodent models, which have been studied most extensively, and emphasize that clinically relevant information can be gained from preclinical models. Furthermore, we explore the numerous potential factors that may confound the interpretation of emerging data from animal models, such as the specific seizure induction method (e.g., chemical, electrical, traumatic, genetic), the role of species and strain, environmental factors (e.g., laboratory environment, handling, epigenetics), and the behavioral assays that are chosen to evaluate the various aspects of neural behavior and cognition. Overall, the interplay between epilepsy and its neurobehavioral comorbidities is undoubtedly multifactorial, involving brain structural changes, network-level differences, molecular signaling abnormalities, and other factors. Animal models are well poised to help dissect the shared pathophysiological mechanisms, neurological sequelae, and biomarkers of epilepsy and its comorbidities.