Rare and Complex Epilepsies from Childhood to Adulthood: Requirements for Separate Management or Scope for a Lifespan Holistic Approach?

Exploring potential key genes and disease mechanisms in early-onset genetic epilepsy via integrated bioinformatics analysis

Epilepsy is a severe common neurological disease affecting all ages. Epilepsy with onset before the age of 5 years, designated early-onset epilepsy (EOE), is of special importance. According to previous studies, genetic factors contribute significantly to the pathogenesis of EOE that remains unclear and must be explored. So, a list of 229 well-selected EOE-associated genes expressed in the brain was created for the investigation of genetic factors and molecular mechanisms involved in its pathogenesis. Enrichment analysis showed that among significant pathways were nicotine addiction, GABAergic synapse, synaptic vesicle cycle, regulation of membrane potential, cholinergic synapse, dopaminergic synapse, and morphine addiction. Performing an integrated analysis as well as protein-protein interaction network-based approaches with the use of GO, KEGG, ClueGO, cytoHubba and 3 network metrics, 12 hub genes were identified, seven of which, CDKL5, GABRA1, KCNQ2, KCNQ3, SCN1A, SCN8A and STXBP1, were identified as key genes (via Venn diagram analysis). These key genes are mostly enriched in SNARE interactions in vesicular transport, regulation of membrane potential and synaptic vesicle exocytosis. Clustering analysis of the PPI network via MCODE showed significant functional modules, indicating also other pathways such as N-Glycan biosynthesis and protein N-linked glycosylation, retrograde endocannabinoid signaling, mTOR signaling and aminoacyl-tRNA biosynthesis. Drug-gene interaction analysis identified a number of drugs as potential medications for EOE, among which the non-FDA approved drugs azetukalner (under clinical development), indiplon and ICA-105665 and the FDA approved drugs retigabine, ganaxolone and methohexital.

Adult phenotypes of genetic developmental and epileptic encephalopathies

Developmental and epileptic encephalopathies constitute a group of severe epilepsies, with seizure onset typically occurring in infancy or childhood, and diverse clinical manifestations, including neurodevelopmental deficits and multimorbidities. Many have genetic aetiologies, identified in up to 50% of individuals. Whilst classically considered paediatric disorders, most are compatible with survival into adulthood, but their adult phenotypes remain inadequately understood. This cross-sectional study presents detailed phenotypes of 129 adults (age range 17-71 years), with genetic developmental and epileptic encephalopathies involving causal variants in 42 genes. We describe diverse disease aspects, and we sought genetic insights from the age-related trends of expression of the genes involved. Most developmental and epileptic encephalopathies (69.7%) are epileptic encephalopathies in adulthood, with the presence of epileptic encephalopathy correlating with worse cognitive phenotypes (P = 0.0007). However, phenotypic variability was observed, ranging from those with epileptic encephalopathy to seizure-free individuals with normal EEG or intermediate clinical and EEG phenotypes. This variability was found across individual genes and age-related gene expression trends, suggesting that other influential factors are likely at play. Mobility, feeding and communication impairments were common, with significant dependence on others for activities of daily living. Neurological and psychiatric comorbidities were most prevalent, along with additional systemic comorbidities observed, particularly musculoskeletal, cardiac and gastrointestinal conditions, highlighting the need for comprehensive and multisystemic monitoring. Despite an average diagnostic delay of 25.2 years, aetiology-based therapeutic interventions were feasible for 54.8% of the cohort, underscoring the critical need for genome-wide genetic testing for adults with these phenotypes. Optimizing seizure control remains necessary, but it may not be sufficient to ensure good outcomes, which may differ significantly from childhood metrics, like cognitive function and independence in daily living. Therapies addressing additional aspects beyond seizures are necessary for improving overall outcomes. Understanding the intricate relationship between molecular pathways and the age-related trends of gene expression is crucial for development of appropriate gene-specific therapies and timely intervention. Whilst prospective data are also needed to define these complexities, such studies of necessity take years to acquire: insights from adults can inform care strategies for both paediatric and adult populations now.

Dravet syndrome: A systematic literature review of the illness burden

We performed a systematic literature review and narrative synthesis according to a pre-registered protocol (Prospero: CRD42022376561) to identify the evidence associated with the burden of illness in Dravet syndrome (DS), a developmental and epileptic encephalopathy characterized by drug-resistant epilepsy with neurocognitive and neurobehavioral impairment. We searched MEDLINE, Embase, and APA PsychInfo, Cochrane's database of systematic reviews, and Epistemonikos from inception to June 2022. Non-interventional studies reporting on epidemiology (incidence, prevalence, and mortality), patient and caregiver health-related quality of life (HRQoL), direct and indirect costs and healthcare resource utilization were eligible. Two reviewers independently carried out the screening. Pre-specified data were extracted and a narrative synthesis was conducted. Overall, 49 studies met the inclusion criteria. The incidence varied from 1:15 400-1:40 900, and the prevalence varied from 1.5 per 100 000 to 6.5 per 100 000. Mortality was reported in 3.7%-20.8% of DS patients, most commonly due to sudden unexpected death in epilepsy and status epilepticus. Patient HRQoL, assessed by caregivers, was lower than in non-DS epilepsy patients; mean scores (0 [worst] to 100/1 [best]) were 62.1 for the Kiddy KINDL/Kid-KINDL, 46.5-54.7 for the PedsQL and 0.42 for the EQ-5D-5L. Caregivers, especially mothers, were severely affected, with impacts on their time, energy, sleep, career, and finances, while siblings were also affected. Symptoms of depression were reported in 47%-70% of caregivers. Mean total direct costs were high across all studies, ranging from $11 048 to $77 914 per patient per year (PPPY), with inpatient admissions being a key cost driver across most studies. Mean costs related to lost productivity were only reported in three publications, ranging from approximately $19 000 to $20 000 PPPY ($17 596 for mothers vs $1564 for fathers). High seizure burden was associated with higher resource utilization, costs and poorer HRQoL. The burden of DS on patients, caregivers, the healthcare system, and society is profound, reflecting the severe nature of the syndrome. Future studies will be able to assess the impact that newly approved therapies have on reducing the burden of DS.

Transition to adult care in epilepsy: A systematic review

The transfer from paediatric to adult care can be a complex process in children with epilepsy. Inadequate care during this phase can affect long-term medical and psychosocial outcomes. The aim of this study was to review studies on transitional care from paediatric to adult healthcare for young persons with epilepsy in order to synthesize evidence for best practice. We undertook a systematic review following PRISMA guidelines and employed narrative synthesis. A total of 36 articles were included, of which 11 were interventional studies and 25 observational studies. Study quality was rated as 'good' for only four studies. Interventions included joint or multidisciplinary clinics, education (patient and health professional education) and extended service provision (Saturday clinics, peer-groups). All studies observed a positive effect experienced by the participants, regardless of intervention type. Observational studies showed that transition plans/programmes are asked for but frequently not existing or not adapted to subgroups with intellectual disability or other neurodevelopmental conditions. The results of this systematic review on transitional care in epilepsy suggest that a planned transition process likely enhances medical and psychosocial outcomes for young people with epilepsy, but the body of evidence is limited and there are significant gaps in knowledge of what efficacious transition constitutes. More studies are needed employing qualitative and quantitative methods to further explore the needs of young people with epilepsy and their families but also robust study designs to investigate the impact of interventions on medical and psychosocial outcomes.