OBJECTIVE
The polygenic risk score (PRS) for individuals with genetic generalized epilepsy (GGE) quantifies the common risk variants in genes identified in genome-wide association studies. We hypothesized that the phenotype of GGE patients differs based on their GGE PRS.
METHODS
We identified participants with highest (n = 59) versus lowest (n = 48) PRS from the GGE patients (n = 2256) recruited through the Epi25 Collaborative for comparison. Detailed clinical data were acquired retrospectively for the 59 high PRS and 48 low PRS individuals with GGE from the Epi25 database and from the contributing centers. For validation, we accessed a larger cohort (n = 1175) of patients with GGE included in the Epi25 Collaborative.
RESULTS
This study found no difference in phenotypic features of patients between the high-PRS GGE and low-PRS GGE subgroups, including age at onset, family history, and specific GGE syndrome. However, more patients from the lowest compared to the highest PRS subgroup were pharmacoresistant (31.7% vs. 8.9%, p = .01). On validation in a larger cohort, the PRS did not differ in the group of pharmacoresistant compared to nonpharmacoresistant patients.
SIGNIFICANCE
No meaningful association between PRS and age at onset, history of febrile seizures, pre-/perinatal complications, epilepsy syndromes, seizure types, co-occurrence of functional/dissociative (nonepileptic) seizures, psychiatric comorbidities, electroencephalographic/magnetic resonance imaging findings, or drug response could be demonstrated in this study of people with GGE.
Sophie von Brauchitsch, Nils Hartung, R. Karge et al.· Epilepsia· 0 citations
Pathogenic KCNQ2 variants are the most common genetic cause of neonatal-onset epilepsies, with phenotypes ranging from self-limited (familial) neonatal epilepsy (SeL(F)NE) to severe developmental and epileptic encephalopathy (KCNQ2-DEE). Sodium channel blockers (SCBs) have shown promise for seizure control in these disorders, but their impact on neurodevelopmental outcomes and possible relationship with timing of initiation remain incompletely understood. We leveraged a large, multicentre international cohort comprising 282 individuals with pathogenic KCNQ2 variants to retrospectively assess the effectiveness of antiseizure medications (ASMs), particularly SCBs, on seizure control and neurodevelopment. Individuals were grouped according to the predicted variant-specific functional effects: loss-of-function (LOF) variants known to be associated with SeL(F)NE or DEE respectively, and gain-of-function (GOF) variants. Epilepsy course, ASM effectiveness, and neurodevelopmental milestones were systematically collected and analysed, including time-to-event and adjusted outcome analyses. SCBs, especially carbamazepine (CBZ) and oxcarbazepine (OXC), emerged as the most effective ASMs in both LOF groups. In LOF KCNQ2-DEE, time-to-event analyses showed that early SCB initiation (≤1 month) was associated with earlier seizure offset. Early SCB initiation was also associated with significantly more favourable neurodevelopmental outcomes, including higher rates of attaining major motor milestones. This association remained significant after adjustment for seizure control by 1 month and total ASM burden. Considerable phenotypic variability persisted, with some individuals experiencing severe impairment despite early seizure control and SCB initiation, suggesting that variant severity and additional genetic or biological modifiers contribute to outcome heterogeneity.Our results support the use of SCBs, particularly CBZ and OXC, as first-line therapy in (LOF) KCNQ2-DEE and SeL(F)NE. Earlier SCB initiation was associated with earlier seizure offset and more favourable developmental outcomes, underscoring the importance of early genetic diagnosis and timely SCB therapy. We however emphasise that early treatment is not universally transformative and further prospective work, including exploration of targeted therapies and standardised neurodevelopmental assessments, is needed to optimise long-term outcomes in this heterogeneous population.
C. Millevert, M. Hairabedian, Samuel Dahan et al.· Brain : a journal of neurolo...· 0 citations
The role of CNVs in the etiology of DEE in an adult cohort is investigated, to define the most appropriate diagnostic approach in this population and support the clinical utility of CNV analysis inclusion in the diagnostic workflow for adult patients with DEE.
L. Licchetta, G. Bruschi, T. Giangregorio et al.· Epilepsia· 1 citation
The electroclinical and developmental features of three patients carrying truncating TANC2 variants identified through trio‐exome sequencing within the European collaborative platform NETRE are described, expanding the known clinical spectrum of TANC2‐related disorders and suggesting that selected patients may have a more favorable seizure course than expected.
L. Perilli, Carlotta Stipa, Gianmichele Villano et al.· Epilepsia Open· 0 citations