Expanding the genotype-phenotype spectrum in SCN8A-related disorders.

BACKGROUND: SCN8A-related disorders are a group of variable conditions caused by pathogenic variations in SCN8A. Online Mendelian Inheritance in Man (OMIM) terms them as developmental and epileptic encephalopathy 13, benign familial infantile seizures 5 or cognitive impairment with or without cerebellar ataxia. METHODS: In this study, we describe clinical and genetic results on eight individuals from six families with SCN8A pathogenic variants identified via exome sequencing. RESULTS: Clinical findings ranged from normal development with well-controlled epilepsy to significant developmental delay with treatment-resistant epilepsy. Three novel and three reported variants were observed in SCN8A. Electrophysiological analysis in transfected cells revealed a loss-of-function variant in Patient 4. CONCLUSIONS: This work expands the clinical and genotypic spectrum of SCN8A-related disorders and provides electrophysiological results on a novel loss-of-function SCN8A variant.

Trajectories of parent well-being in children with drug-resistant epilepsy.

OBJECTIVE: This longitudinal cohort study aimed to identify trajectories of parent well-being over the first 2 years after their child's evaluation for candidacy for epilepsy surgery, and to identify the baseline clinical and demographic characteristics associated with these trajectories. Parent well-being was based on parent depressive and anxiety symptoms and family resources (i.e., family mastery and social support). METHODS: Parents of 259 children with drug-resistant epilepsy (105 of whom eventually had surgery) were recruited from eight epilepsy centers across Canada at the time of their evaluation for epilepsy surgery candidacy. Participants were assessed at baseline and 6-month, 1-year, and 2-year follow-up. The trajectories of parents' depressive symptoms, anxiety symptoms, and family resources were jointly estimated using multigroup latent class growth models. RESULTS: The analyses identified three trajectories: an optimal-stable group with no/minimal depressive or anxiety symptoms, and high family resources that remained stable over time; a mild-decreasing-plateau group with mild depressive and anxiety symptoms that decreased over time then plateaued, and intermediate family resources that remained stable; and a moderate-decreasing group with moderate depressive and anxiety symptoms that decreased slightly, and low family resources that remained stable over time. Parents of children with higher health-related quality of life, fathers, and parents who had higher household income were more likely to have better trajectories of well-being. Treatment type was not associated with the trajectory groups, but parents whose children were seizure-free at the time of the last follow-up were more likely to have better trajectories (optimal-stable or mild-decreasing-plateau trajectories). SIGNIFICANCE: This study documented distinct trajectories of parent well-being, from the time of the child's evaluation for epilepsy surgery. Parents who present with anxiety and depressive symptoms and low family resources do not do well over time. They should be identified and offered supportive services early in their child's epilepsy treatment history.

A longitudinal cohort study of mediators of health-related quality of life after pediatric epilepsy surgery or medical treatment.

OBJECTIVES: The purpose of this longitudinal cohort study was to examine the variables that influence health-related quality of life (HRQOL) after epilepsy surgery in children. We examined whether treatment type (surgical vs medical therapy) and seizure control are related to other variables that have been shown to influence HRQOL, namely depressive symptoms in children with epilepsy or their parents, and the availability of family resources. METHODS: In total, 265 children with drug-resistant epilepsy were recruited from eight epilepsy centers across Canada at the time of their evaluation for candidacy for epilepsy surgery and were assessed at baseline, 6-month, 1-year, and 2-year follow-up. Parents completed the Quality of Life in Childhood Epilepsy Questionnaire (QOLCE-55) and measures of family resources and depression; children completed depression inventories. Causal mediation analyses using natural effect models were used to evaluate the extent to which the relationship between treatment and HRQOL was explained by seizure control, child and parent depressive symptoms, and family resources. RESULTS: Overall, 111 children underwent surgery and 154 were treated with medical therapy only. The HRQOL scores of surgical patients were 3.4 points higher (95% confidence interval [CI]: -0.2, 7.0) relative to medical patients at the 2-year follow-up after adjusting for baseline covariates, with 66% of the effect of surgery attributed to seizure control. Child or parent depressive symptoms and family resources had negligible mediation effects between treatment and HRQOL. The effect of seizure control on HRQOL was not mediated by child or parent depressive symptoms, or by family resources. SIGNIFICANCE: The findings demonstrate that seizure control is on the causal pathway between epilepsy surgery and improved HRQOL in children with drug-resistant epilepsy. However, child and parent depressive symptoms and family resources were not significant mediators. The results highlight the importance of achieving seizure control to improve HRQOL.

Clinician preferences for neurotechnologies in pediatric drug-resistant epilepsy: A discrete choice experiment.

OBJECTIVE: Novel and minimally invasive neurotechnologies offer the potential to reduce the burden of epilepsy while avoiding the risks of conventional resective surgery. Few neurotechnologies have been tested in randomized controlled trials with pediatric populations, leaving clinicians to face decisions about whether to recommend these treatments with insufficient evidence about the relevant risks and benefits. This study specifically explores the preferences of clinicians for treating pediatric drug-resistant epilepsy (DRE) with novel neurotechnologies. METHODS: A discrete-choice experiment (DCE) was designed to elicit the preferences of clinicians with experience in treating children with DRE using novel neurotechnological interventions. The preferences for six key attributes used when making treatment decisions (chances of clinically significant improvement in seizures, major and minor risks from intervention, availability of evidence, financial burden for the family, and access to the intervention) were estimated using a conditional logit model. The estimates from this model were then used to predict the adoption of existing novel neurotechnological interventions. RESULTS: Sixty-eight clinicians completed the survey: 33 neurosurgeons, 28 neurologists, and 7 other clinicians. Most clinicians were working in the United States (74%), and the remainder (26%) in Canada. All attributes, apart from the nearest location with access to the intervention, influenced preferences significantly. The chance of clinically significant improvement in seizures was the most positive influence on clinician preferences, but low-quality evidence and a higher risk of major complications could offset these preferences. Of the existing neurotechnological interventions, vagus nerve stimulation was predicted to have the highest likelihood of adoption; deep brain stimulation had the lowest likelihood of adoption. SIGNIFICANCE: The preferences of clinicians are drive primarily by the likelihood of achieving seizure freedom for their patients, but preferences for an intervention are largely eradicated if only low quality of evidence supporting the intervention is available. Until better evidence supporting the use of potentially effective, novel neurotechnologies becomes available, clinicians are likely to prefer more established treatments.

Seizure action plans in the pediatric population with epilepsy: Uptake, determinants, and parental interest in a mobile application.

BACKGROUND: Status epilepticus (SE) is a common pediatric neurological emergency that requires timely treatment to minimize morbidity and mortality, yet administration of rescue medications is often delayed and underdosed. Seizure action plans (SAPs) outline the steps that should be taken by parents and caregivers in case of SE in order to optimize patient outcomes. Our study determined the uptake of SAPs in a pediatric population with epilepsy and assessed parental interest in a SAP mobile application. METHODS: A survey was distributed to parents of patients with epilepsy aged 1 month to 19 years at British Columbia Children's Hospital. Following chart review, univariate and multivariate analyses were performed to identify variables that predict whether patients have SAPs. A systematic search of available mobile applications for epilepsy management was conducted. RESULTS: Of 192 participants, 62% have SAPs. On univariate analysis, history of prior SE and male gender increased likelihood of SAP. On logistic regression, Nagelkerke R2 was 0.204 and our model correctly predicted 82% of patients with SAPs. 83% of parents were interested in a SAP mobile application. There are currently 40 mobile applications available for epilepsy management, but only 15% of respondents reported using them. CONCLUSIONS: There is a need to increase the percentage of patients with epilepsy with SAPs, particularly in those at greater risk of SE. Most parents would find a SAP mobile application valuable in their child's epilepsy management. There is a gap between the high parental interest in mobile applications for epilepsy management and their current use of such applications.

Rapid Implementation of Virtual Health in a Pediatric Neurology Practice During COVID-19.

During the COVID-19 pandemic, the Division of Neurology at BC Children's Hospital rapidly transitioned to almost exclusively virtual health. In April 2020, 96% of outpatient visits were done virtually (64%) or by telephone, and only 4.2% were in-person. Total clinic visit numbers were unchanged compared to previous months. Neurologists reported high satisfaction with the virtual history and overall assessment, while the physical examination was less reliable. Additional in-person visits were rarely required. Rapid, sustained adoption of virtual health is possible in a pediatric neurology setting, providing reliable care that is comparable to in-person consultations when physical distancing is necessary.

De Novo Mutations in YWHAG Cause Early-Onset Epilepsy.

Massively parallel sequencing has revealed many de novo mutations in the etiology of developmental and epileptic encephalopathies (EEs), highlighting their genetic heterogeneity. Additional candidate genes have been prioritized in silico by their co-expression in the brain. Here, we evaluate rare coding variability in 20 candidates nominated with the use of a reference gene set of 51 established EE-associated genes. Variants within the 20 candidate genes were extracted from exome-sequencing data of 42 subjects with EE and no previous genetic diagnosis. We identified 7 rare non-synonymous variants in 7 of 20 genes and performed Sanger sequence validation in affected probands and parental samples. De novo variants were found only in SLC1A2 (aka EAAT2 or GLT1) (c.244G>A [p.Gly82Arg]) and YWHAG (aka 14-3-3γ) (c.394C>T [p.Arg132Cys]), highlighting the potential cause of EE in 5% (2/42) of subjects. Seven additional subjects with de novo variants in SLC1A2 (n = 1) and YWHAG (n = 6) were subsequently identified through online tools. We identified a highly significant enrichment of de novo variants in YWHAG, establishing their role in early-onset epilepsy, and we provide additional support for the prior assignment of SLC1A2. Hence, in silico modeling of brain co-expression is an efficient method for nominating EE-associated genes to further elucidate the disorder's etiology and genotype-phenotype correlations.

Loss-of-Function and Gain-of-Function Mutations in KCNQ5 Cause Intellectual Disability or Epileptic Encephalopathy.

KCNQ5 is a highly conserved gene encoding an important channel for neuronal function; it is widely expressed in the brain and generates M-type current. Exome sequencing identified de novo heterozygous missense mutations in four probands with intellectual disability, abnormal neurological findings, and treatment-resistant epilepsy (in two of four). Comprehensive analysis of this potassium channel for the four variants expressed in frog oocytes revealed shifts in the voltage dependence of activation, including altered activation and deactivation kinetics. Specifically, both loss-of-function and gain-of-function KCNQ5 mutations, associated with increased excitability and decreased repolarization reserve, lead to pathophysiology.

Exome Sequencing and the Management of Neurometabolic Disorders.

BACKGROUND: Whole-exome sequencing has transformed gene discovery and diagnosis in rare diseases. Translation into disease-modifying treatments is challenging, particularly for intellectual developmental disorder. However, the exception is inborn errors of metabolism, since many of these disorders are responsive to therapy that targets pathophysiological features at the molecular or cellular level. METHODS: To uncover the genetic basis of potentially treatable inborn errors of metabolism, we combined deep clinical phenotyping (the comprehensive characterization of the discrete components of a patient's clinical and biochemical phenotype) with whole-exome sequencing analysis through a semiautomated bioinformatics pipeline in consecutively enrolled patients with intellectual developmental disorder and unexplained metabolic phenotypes. RESULTS: We performed whole-exome sequencing on samples obtained from 47 probands. Of these patients, 6 were excluded, including 1 who withdrew from the study. The remaining 41 probands had been born to predominantly nonconsanguineous parents of European descent. In 37 probands, we identified variants in 2 genes newly implicated in disease, 9 candidate genes, 22 known genes with newly identified phenotypes, and 9 genes with expected phenotypes; in most of the genes, the variants were classified as either pathogenic or probably pathogenic. Complex phenotypes of patients in five families were explained by coexisting monogenic conditions. We obtained a diagnosis in 28 of 41 probands (68%) who were evaluated. A test of a targeted intervention was performed in 18 patients (44%). CONCLUSIONS: Deep phenotyping and whole-exome sequencing in 41 probands with intellectual developmental disorder and unexplained metabolic abnormalities led to a diagnosis in 68%, the identification of 11 candidate genes newly implicated in neurometabolic disease, and a change in treatment beyond genetic counseling in 44%. (Funded by BC Children's Hospital Foundation and others.).

Position Statement on the Use of Medical Cannabis for the Treatment of Epilepsy in Canada.

In Canada, recreational use of cannabis was legalized in October 2018. This policy change along with recent publications evaluating the efficacy of cannabis for the medical treatment of epilepsy and media awareness about its use have increased the public interest about this agent. The Canadian League Against Epilepsy Medical Therapeutics Committee, along with a multidisciplinary group of experts and Canadian Epilepsy Alliance representatives, has developed a position statement about the use of medical cannabis for epilepsy. This article addresses the current Canadian legal framework, recent publications about its efficacy and safety profile, and our understanding of the clinical issues that should be considered when contemplating cannabis use for medical purposes.

Énoncé de position quant à l'utilisation du cannabis médical dans le traitement de l'épilepsie. L'utilisation du cannabis à des fins récréatives a été légalisée au Canada en octobre 2018. Parallèlement à ce changement de politique, de récentes publication visant à évaluer l'efficacité du cannabis dans le traitement de l'épilepsie, de même qu'une sensibilisation médiatique accrue en ce qui concerne son utilisation, ont eu pour effet d'augmenter l'intérêt du grand public à son égard. Le Comité médical thérapeutique de la Ligue canadienne contre l'épilepsie (LCCE), de concert avec un groupe multidisciplinaire d'experts et des représentants de l'Alliance canadienne de l'épilepsie, a ainsi élaboré un énoncé de position en ce qui regarde l'utilisation du cannabis médical dans le traitement de l'épilepsie. Cet article entend donc aborder le cadre légal qui prévaut actuellement au Canada et examiner de récentes publications s'étant penchées sur le profil sécuritaire et sur l'efficacité du cannabis. De plus, nous voulons apporter un éclairage au sujet des aspects cliniques dont il faudrait tenir compte au moment d'envisager l'utilisation du cannabis à des fins médicales.

Secondary Abnormal CSF Neurotransmitter Metabolite Profiles in a Pediatric Tertiary Care Centre.

BACKGROUND: Secondary neurotransmitter deficiencies have been reported in several reviews. Our primary aim was to assess the relationship among epilepsy, antiseizure medications, and specific neurotransmitter abnormalities. We also evaluated movement disorders and brain abnormalities via magnetic resonance imaging scans in patients with secondary neurotransmitter defects. METHODS: This is a retrospective case series of 376 patients who underwent neurotransmitter analysis at BC Children's Hospital between 2009 and 2013, for a variety of neurological presentations. The biochemical genetics laboratory database was interrogated for results of cerebrospinal fluid neurotransmitter analyses. Clinical data for patients with abnormal results were collected from the hospital charts. Statistical analysis included one-way analysis of variance, chi-square, and a two-way contingency table. RESULTS: Abnormal neurotransmitter values were identified in 67 (17.8%) patients, two (0.53%) of which were attributable to a congenital neurotransmitter disorder and 11 (16.9%) secondary to other genetic diagnoses. Of 64 patients with secondary abnormal neurotransmitter values, 38 (59%) presented with epilepsy and 20 (31%) with movement disorders. A combination of epilepsy and movement disorder was less frequent. DISCUSSION: Acknowledging the limitations of this retrospective chart review, we conclude that, in our cohort, in addition to patients with movement disorders, a considerable number of patients with epilepsy and epileptic encephalopathy also showed secondary neurotransmitter mono-amine abnormalities. There is no clear relation, however, between clinical phenotype and type of neurotransmitter affected. In addition, no association was identified between the type of antiseizure medications and affected neurotransmitter type. We outline the need for prospective studies to further enrich our understanding of the relation between epilepsy and neurotransmitters with a focus on improving treatments and patient outcomes.

Assessing an Interactive Online Tool to Support Parents' Genomic Testing Decisions.

Clinical use of genome-wide sequencing (GWS) requires pre-test genetic counseling, but the availability of genetic counseling is limited. We developed an interactive online decision-support tool, DECIDE, to make genetic counseling, patient education, and decision support more readily available. We performed a non-inferiority trial comparing DECIDE to standard genetic counseling to assess the clinical value of DECIDE for pre-GWS counseling. One hundred and six parents considering GWS for their children with epilepsy were randomized to conventional genetic counseling or DECIDE. Following the intervention, we measured parents' knowledge and empowerment and asked their opinions about using DECIDE. Both DECIDE and conventional genetic counseling significantly increased parents' knowledge, with no difference between groups. Empowerment also increased but by less than 2% in each group. Parents liked using DECIDE and found it useful; 81% would recommend it to others; 49% wished to use it along with a genetic counselor; 26% of parents preferred to see a genetic counselor; 7% preferred DECIDE alone; and 18% had no preference. DECIDE appears equivalent to genetic counseling at conveying information. In addition, it was highly acceptable to the majority of study participants, many of whom indicated that it was useful to their decision-making. Use of DECIDE as a pre-test tool may extend genetic counseling resources.

ILAE classification of the epilepsies: Position paper of the ILAE Commission for Classification and Terminology.

The International League Against Epilepsy (ILAE) Classification of the Epilepsies has been updated to reflect our gain in understanding of the epilepsies and their underlying mechanisms following the major scientific advances that have taken place since the last ratified classification in 1989. As a critical tool for the practicing clinician, epilepsy classification must be relevant and dynamic to changes in thinking, yet robust and translatable to all areas of the globe. Its primary purpose is for diagnosis of patients, but it is also critical for epilepsy research, development of antiepileptic therapies, and communication around the world. The new classification originates from a draft document submitted for public comments in 2013, which was revised to incorporate extensive feedback from the international epilepsy community over several rounds of consultation. It presents three levels, starting with seizure type, where it assumes that the patient is having epileptic seizures as defined by the new 2017 ILAE Seizure Classification. After diagnosis of the seizure type, the next step is diagnosis of epilepsy type, including focal epilepsy, generalized epilepsy, combined generalized, and focal epilepsy, and also an unknown epilepsy group. The third level is that of epilepsy syndrome, where a specific syndromic diagnosis can be made. The new classification incorporates etiology along each stage, emphasizing the need to consider etiology at each step of diagnosis, as it often carries significant treatment implications. Etiology is broken into six subgroups, selected because of their potential therapeutic consequences. New terminology is introduced such as developmental and epileptic encephalopathy. The term benign is replaced by the terms self-limited and pharmacoresponsive, to be used where appropriate. It is hoped that this new framework will assist in improving epilepsy care and research in the 21st century.

Manifestations of Tuberous Sclerosis Complex: The Experience of a Provincial Clinic.

BACKGROUND: Tuberous sclerosis complex (TSC) is a neurocutaneous disorder with a wide spectrum of manifestations. Recent consensus recommendations stress the importance of multidisciplinary management of children with TSC. The objective of this study was to examine the manifestations of TSC at a large referral centre to determine the care needs of this population. METHODS: A retrospective, systematic chart review was performed of children with TSC managed at British Columbia Children's Hospital. Patients were identified through epilepsy and clinical neurophysiology databases. RESULTS: The study population comprised 81 patients, born between 1987 and 2014, who were a median of 10 years (range, 0.2-23.2) at most recent follow-up. Epilepsy occurred in 91% of patients, including 32% with a history of infantile spasms. Nineteen patients underwent epilepsy surgery, nine (47%) of whom were seizure-free at most recent follow-up. Overall, 61% of epilepsy patients had been seizure-free for at least 1 year at the time of last follow-up. Neuropsychiatric disorders were diagnosed in 49% of children, with autism (25%), attention deficit hyperactivity order (19%) and anxiety (16%) being the most common. Cardiac rhabdomyomata occurred in 35% of children and renal angiomyolipomas were seen in 43%. A total of 91% had skin manifestations. CONCLUSION: This study outlines the multisystem manifestations of TSC, observed through a large pediatric referral center. Epilepsy and neuropsychiatric disorders are the major source of morbidity in this age group and provide many challenges to the treating clinician. Because a subset of the study population is still quite young, the prevalence of neuropsychiatric disorders is likely underestimated.

Dravet Syndrome: Diagnosis and Long-Term Course.

Dravet syndrome is one of the most severe epilepsy syndromes of early childhood, and it comes with very high morbidity and mortality. The typical presentation is characterized by hemiclonic or generalized clonic seizures triggered by fever during the first year of life, followed by myoclonic, absence, focal and generalized tonic-clonic seizures. Non-convulsive status epilepticus and epileptic encephalopathy are common. Development is normal in the first year of life, but most individuals eventually suffer from intellectual impairment. Dravet syndrome is associated with mutations in the sodium channel alpha1 subunit gene (SCN1A) in 70-80% of individuals. SCN1A mutation results in inhibition of the GABAergic inhibitory interneurons, leading to excessive neuronal excitation. The "interneuron hypothesis" is the current most accepted pathophysiological mechanism of Dravet syndrome. The mortality rate is increased significantly in Dravet syndrome. Ataxia, a characteristic crouched gait and Parkinson's symptoms may develop in some individuals. It is likely that Dravet syndrome is underdiagnosed in adults with treatment-resistant epilepsy. Early diagnosis is important to avoid anti-seizure medications that exacerbate seizures.

Recommendations for HLA-B*15:02 and HLA-A*31:01 genetic testing to reduce the risk of carbamazepine-induced hypersensitivity reactions.

OBJECTIVE: To systematically review evidence on genetic risk factors for carbamazepine (CBZ)-induced hypersensitivity reactions (HSRs) and provide practice recommendations addressing the key questions: (1) Should genetic testing for HLA-B*15:02 and HLA-A*31:01 be performed in patients with an indication for CBZ therapy to reduce the occurrence of CBZ-induced HSRs? (2) Are there subgroups of patients who may benefit more from genetic testing for HLA-B*15:02 or HLA-A*31:01 compared to others? (3) How should patients with an indication for CBZ therapy be managed based on their genetic test results? METHODS: A systematic literature search was performed for HLA-B*15:02 and HLA-A*31:01 and their association with CBZ-induced HSRs. Evidence was critically appraised and clinical practice recommendations were developed based on expert group consensus. RESULTS: Patients carrying HLA-B*15:02 are at strongly increased risk for CBZ-induced Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) in populations where HLA-B*15:02 is common, but not CBZ-induced hypersensitivity syndrome (HSS) or maculopapular exanthema (MPE). HLA-B*15:02-positive patients with CBZ-SJS/TEN have been reported from Asian countries only, including China, Thailand, Malaysia, and India. HLA-B*15:02 is rare among Caucasians or Japanese; no HLA-B*15:02-positive patients with CBZ-SJS/TEN have been reported so far in these groups. HLA-A*31:01-positive patients are at increased risk for CBZ-induced HSS and MPE, and possibly SJS/TEN and acute generalized exanthematous pustulosis (AGEP). This association has been shown in Caucasian, Japanese, Korean, Chinese, and patients of mixed origin; however, HLA-A*31:01 is common in most ethnic groups. Not all patients carrying either risk variant develop an HSR, resulting in a relatively low positive predictive value of the genetic tests. SIGNIFICANCE: This review provides the latest update on genetic markers for CBZ HSRs, clinical practice recommendations as a basis for informed decision making regarding the use of HLA-B*15:02 and HLA-A*31:01 genetic testing in patients with an indication for CBZ therapy, and identifies knowledge gaps to guide future research. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here.

Trajectory of Health-Related Quality of Life After Pediatric Epilepsy Surgery.

Importance: Health-related quality of life (HRQOL) is regarded as a key outcome for evaluating treatment efficacy. However, it is uncertain how HRQOL evolves after epilepsy surgery compared with medical therapy, such as whether it continues to improve over time, improves and then remains stable, or deteriorates after a period of time. Objective: To assess trajectory of HRQOL over 2 years in children with drug-resistant epilepsy (DRE) treated with surgery compared with medical therapy. Design, Setting, and Participants: Prospective cohort study assessing HRQOL longitudinally over 2 years. Participants were children recruited from 8 epilepsy centers in Canada from 2014 to 2019 with suspected DRE aged 4 to 18 years who were evaluated for surgery. Data were analyzed from May 2014 to December 2021. Exposures: Epilepsy surgery or medical therapy. Main Outcomes and Measures: HRQOL was measured using the Quality of Life in Childhood Epilepsy Questionnaire (QOLCE)-55. HRQOL and seizure frequency were assessed at baseline, 6-month, 1-year, and 2-year follow-ups. Clinical, parent, and family characteristics were assessed at baseline. A linear mixed model was used to evaluate HRQOL over time, adjusting for baseline clinical, parent, and family characteristics. Results: There were 111 surgical and 154 medical patients (mean [SD] age at baseline was 11.0 [4.1] years; 118 [45%] were female). At baseline, HRQOL was similar among surgical and medical patients. HRQOL of surgical patients was 3.0 (95% CI, -0.7 to 6.8) points higher at 6-month, 4.9 (95% CI, 0.7 to 9.1) points higher at 1-year, and 5.1 (95% CI, 0.7 to 9.5) points higher at 2-year follow-ups compared with medical patients. Surgical patients experienced greater improvements in social functioning relative to medical patients, but not for cognitive, emotional, and physical functioning. At 2-year follow-up, 72% of surgical patients were seizure-free, compared with 33% of medical patients. Seizure-free patients reported higher HRQOL than those who were not. Conclusions and Relevance: This study provided evidence on the association between epilepsy surgery and children's HRQOL, with improvement in HRQOL occurring within the first year and remaining stable 2 years after surgery. By demonstrating that surgery improved seizure freedom and HRQOL, which has downstream effects such as better educational attainment, reduced health care resource utilization, and health care cost, these findings suggest that the high costs of surgery are justified, and that improved access to epilepsy surgery is necessary.

Expanding the genotype-phenotype spectrum in SCN8A-related disorders.

Background: SCN8A-related disorders are a group of variable conditions caused by pathogenic variations in SCN8A. Online Mendelian Inheritance in Man (OMIM) terms them as developmental and epileptic encephalopathy 13, benign familial infantile seizures 5 or cognitive impairment with or without cerebellar ataxia. Methods: In this study, we describe clinical and genetic results on eight individuals from six families with SCN8A pathogenic variants identified via exome sequencing. Results: Clinical findings ranged from normal development with well-controlled epilepsy to significant developmental delay with treatment-resistant epilepsy. Three novel and three reported variants were observed in SCN8A. Electrophysiological analysis in transfected cells revealed a loss-of-function variant in Patient 4. Conclusions: This work expands the clinical and genotypic spectrum of SCN8A-related disorders and provides electrophysiological results on a novel loss-of-function SCN8A variant.

Pre-Operative Predictors of Health-Related Quality of Life Two Years After Pediatric Epilepsy Surgery: A Prospective Cohort Study.

PURPOSE: Seizure freedom is an important predictor of health-related quality of life (HRQOL) after pediatric epilepsy surgery. This study aimed to identify the pre-operative predictors of HRQOL 2 years after epilepsy surgery in children with drug-resistant epilepsy. METHODS: This multicenter prospective cohort study assessed pre-operative predictors including child (demographics and clinical variables), caregiver (including caregiver depressive and anxiety symptoms) and family characteristics. HRQOL was assessed using the Quality of Life in Childhood Epilepsy Questionnaire (QOLCE)-55 pre-operatively and 2-years after surgery. Univariable linear regression analyses were done to identify significant preoperative predictors of HRQOL 2-years after surgery, followed by multivariable regression. RESULTS: Ninety-five children underwent surgery, mean age was 11.4 (SD=4.2) years, and 59 (62%) were male. Mean QOLCE scores were 57.4 (95%CI: 53.8, 61.0) pre-operatively and 65.6 (95%CI: 62.0, 69.1) after surgery. Univariable regression showed fewer anti-seizure medications (ß=-6.1 [95%CI: -11.2, -1.0], p = 0.019), older age at seizure onset (ß=1.6 [95%CI: 0.8, 2.4], p<0.001), higher pre-operative HRQOL (ß=0.7 [95%CI: 0.5, 0.8], p<0.001), higher family resources (ß=0.6 [95%CI: 0.3, 0.9], p<0.001), better family relationships (ß=1.7 [95%CI: 0.3, 3.1], p = 0.017) and lower family demands (ß=-0.9 [95%CI: -1.5, -0.4], p<0.001) were associated with higher HRQOL after surgery. Caregiver characteristics did not predict HRQOL after surgery (p>0.05). Multivariable regression showed older age at seizure onset (ß=4.6 [95%CI: 1.6, 7.6], p = 0.003) and higher pre-operative HRQOL (ß=10.2 [95%CI: 6.8, 13.6], p<0.001) were associated with higher HRQOL after surgery. CONCLUSION: This study underscores the importance of optimizing pre-operative HRQOL to maximize HRQOL outcome after pediatric epilepsy surgery.