GWAS meta-analysis of over 29,000 people with epilepsy identifies 26 risk loci and subtype-specific genetic architecture

Epilepsy is a highly heritable disorder affecting over 50 million people worldwide, of which about one-third are resistant to current treatments. Here we report a multi-ancestry genome-wide association study including 29,944 cases, stratified into three broad categories and seven subtypes of epilepsy, and 52,538 controls. We identify 26 genome-wide significant loci, 19 of which are specific to genetic generalized epilepsy (GGE). We implicate 29 likely causal genes underlying these 26 loci. SNP-based heritability analyses show that common variants explain between 39.6% and 90% of genetic risk for GGE and its subtypes. Subtype analysis revealed markedly different genetic architectures between focal and generalized epilepsies. Gene-set analyses of GGE signals implicate synaptic processes in both excitatory and inhibitory neurons in the brain. Prioritized candidate genes overlap with monogenic epilepsy genes and with targets of current antiseizure medications. Finally, we leverage our results to identify alternate drugs with predicted efficacy if repurposed for epilepsy treatment.

Brivaracetam in the Treatment of Patients with Epilepsy-First Clinical Experiences

Objectives

To assess first clinical experiences with brivaracetam (BRV) in the treatment of epilepsies.

Methods

Data on patients treated with BRV from February to December 2016 and with at least one clinical follow-up were collected from electronic patient records. Data on safety and efficacy were evaluated retrospectively.

Results

In total, 93 patients were analyzed; 12 (12.9%) received BRV in monotherapy. The mean duration to follow-up was 4.85 months (MD = 4 months; SD = 3.63). Fifty-seven patients had more than one seizure per month at baseline and had a follow-up of more than 4 weeks; the rate of ≥50% responders was 35.1% (n = 20) in this group, of which five (8.8%) patients were newly seizure-free. In 50.5% (47/93), patients were switched from levetiracetam (LEV) to BRV, of which 43 (46.2%) were switched immediately. Adverse events (AE) occurred in 39.8%, with 22.6% experiencing behavioral and 25.8% experiencing non-behavioral AE. LEV-related AE (LEV-AE) were significantly reduced by switching to BRV. The discontinuation of BRV was reported in 26/93 patients (28%); 10 of those were switched back to LEV with an observed reduction of AE in 70%. For clinical reasons, 12 patients received BRV in monotherapy, 75% were seizure–free, and previous LEV-AE improved in 6/9 patients. BRV-related AE occurred in 5/12 cases, and five patients discontinued BRV.

Conclusion

BRV seems to be a safe, easy, and effective option in the treatment of patients with epilepsy, especially in the treatment of patients who have psychiatric comorbidities and might not be good candidates for LEV treatment. BRV broadens the therapeutic spectrum and facilitates personalized treatment.

First clinical postmarketing experiences in the treatment of epilepsies with brivaracetam: a retrospective observational multicentre study

OBJECTIVES

Brivaracetam (BRV) is the latest approved antiepileptic drug and acts as a synaptic vesicle protein 2A ligand. The aim of the present study was to evaluate the efficacy and tolerability of BRV in the clinical setting.

DESIGN

Retrospective, observational multicentre study.

SETTING

We retrospectively collected clinical data of patients who received BRV in 10 epilepsy centres using a questionnaire that was answered by the reporting neurologist.

PARTICIPANTS

Data of 615 epilepsy patients treated with BRV were included in the study.

PRIMARY AND SECONDARY OUTCOME MEASURES

Efficacy regarding seizure frequency and tolerability of BRV were evaluated. Descriptive statistics complemented by X² contingency tests and effect sizes were performed.

RESULTS

Overall, 44% of the patients had a decreased, 38% a stable and 18% an increased seizure frequency. 17% of patients achieved seizure freedom after initiation of BRV. The seizure frequency decreased in 63% of 19 patients with BRV monotherapy. 27% reported adverse effects, but only 10% of patients with monotherapy. Brivaracetam was significantly more often associated with decreased seizure frequency in levetiracetam (LEV) naïve patients (p=0.012), but BRV also led to a decreased seizure frequency in 42% of patients who had been treated with LEV before, including 17% of patients who were completely seizure free. Adverse effects under LEV improved in 62% and deteriorated in 2% of patients after the switch to BRV. At latest follow-up (mean±SD = 26.3±6.5 months), 68% were still on BRV.

CONCLUSIONS

The present study shows that results of the phase III studies on BRV match data from real life clinical settings. Brivaracetam seems to be a useful alternative in patients who have suffered adverse effects while taking LEV.

Gender differences in concerns about planning to have children and child-rearing among patients with epilepsy: A prospective, multicenter study with 477 patients from Germany

OBJECTIVE

To analyze the concerns and worries about planning to have children and being a parent as a person with epilepsy and investigate gender differences in these perceptions.

METHODS

The Epi2020 study was a large multicenter study focusing on different healthcare aspects of adult patients with epilepsy in Germany. In addition to basic clinical and demographic characteristics, patients were asked to answer a questionnaire regarding their plan to have children, if they had children, and concerns about their children's health. Data were analyzed to detect differences between men and women with epilepsy according to age group.

RESULTS

In total, 477 patients with epilepsy with a mean age of 40.5 years (SD = 15.5, range: 18-83 years) participated in this study; 280 (58.7%) were female and 197 (41.3%) were male. Both women and men frequently reported concerns and worries about having children: In the age group below 45 years of age, 72.5% of women and 58.2% of men described being worried to some extent that their children may also suffer from epilepsy (p = .006). Furthermore, 67.3% of women and 54.2% of men below the age of 45 years reported being worried that their children may be disabled (p = .003). Women were more likely to have family members who are reluctant to support their desire to have children (p = .048).

CONCLUSION

Women with epilepsy of childbearing age are significantly more likely to report major concerns that their children might be disabled or also have epilepsy than men with epilepsy and, therefore, express more concerns about choosing to have a child. However, men also report frequent concerns and worries, and this should be addressed not only on request but should be included in the provision of general information on epilepsy.

Spectrum of Phenotypic, Genetic, and Functional Characteristics in Patients With Epilepsy With KCNC2 Pathogenic Variants

BACKGROUND AND OBJECTIVES

KCNC2 encodes Kv3.2, a member of the Shaw-related (Kv3) voltage-gated potassium channel subfamily, which is important for sustained high-frequency firing and optimized energy efficiency of action potentials in the brain. The objective of this study was to analyze the clinical phenotype, genetic background, and biophysical function of disease-associated Kv3.2 variants.

METHODS

Individuals with KCNC2 variants detected by exome sequencing were selected for clinical, further genetic, and functional analysis. Cases were referred through clinical and research collaborations. Selected de novo variants were examined electrophysiologically in Xenopus laevis oocytes.

RESULTS

We identified novel KCNC2 variants in 18 patients with various forms of epilepsy, including genetic generalized epilepsy (GGE), developmental and epileptic encephalopathy (DEE) including early-onset absence epilepsy, focal epilepsy, and myoclonic-atonic epilepsy. Of the 18 variants, 10 were de novo and 8 were classified as modifying variants. Eight drug-responsive patients became seizure-free using valproic acid as monotherapy or in combination, including severe DEE cases. Functional analysis of 4 variants demonstrated gain of function in 3 severely affected DEE cases and loss of function in 1 case with a milder phenotype (GGE) as the underlying pathomechanisms.

DISCUSSION

These findings implicate KCNC2 as a novel causative gene for epilepsy and emphasize the critical role of KV3.2 in the regulation of brain excitability.

Exome sequencing of 20,979 individuals with epilepsy reveals shared and distinct ultra-rare genetic risk across disorder subtypes

Identifying genetic risk factors for highly heterogeneous disorders like epilepsy remains challenging. Here, we present the largest whole-exome sequencing study of epilepsy to date, with >54,000 human exomes, comprising 20,979 deeply phenotyped patients from multiple genetic ancestry groups with diverse epilepsy subtypes and 33,444 controls, to investigate rare variants that confer disease risk. These analyses implicate seven individual genes, three gene sets, and four copy number variants at exome-wide significance. Genes encoding ion channels show strong association with multiple epilepsy subtypes, including epileptic encephalopathies, generalized and focal epilepsies, while most other gene discoveries are subtype-specific, highlighting distinct genetic contributions to different epilepsies. Combining results from rare single nucleotide/short indel-, copy number-, and common variants, we offer an expanded view of the genetic architecture of epilepsy, with growing evidence of convergence among different genetic risk loci on the same genes. Top candidate genes are enriched for roles in synaptic transmission and neuronal excitability, particularly postnatally and in the neocortex. We also identify shared rare variant risk between epilepsy and other neurodevelopmental disorders. Our data can be accessed via an interactive browser, hopefully facilitating diagnostic efforts and accelerating the development of follow-up studies.

Effect of the revised definition of epilepsy on treatment decisions and seizure recurrence after a first epileptic seizure

BACKGROUND

Studies on risk factors for epilepsy and seizure recurrence after a first seizure are usually based on the old definition of epilepsy with the need for two unprovoked seizures. The current definition of epilepsy allows diagnosis and treatment of epilepsy after a first seizure if the recurrence risk is >60%. We evaluate treatment decisions, seizure recurrence and risk factors for epilepsy related to the application of the new definition of epilepsy.

METHODS

Data of 629 patients with a first seizure were analyzed to investigate changes of treatment decisions and seizure recurrence after the revised definition of epilepsy. We used binary logistic regression to investigate the impact of multiple factors influencing seizure recurrence like EEG and MRI results and administration of ASM.

RESULTS

The proportion of patients receiving ASM significantly increased from 70.4% to 80.5% (p = .015) following the new epilepsy definition, without any significant changes in the recurrence rate (40.8% vs. 45.5% after two years, p > 0.05). The presence of interictal epileptiform discharges (IED) in the EEG increased (OR = 1.98) and administration of ASM decreased (OR = 0.43) recurrence rates significantly.

CONCLUSIONS

The new definition of epilepsy was associated with increased application of ASM, but not with reduced recurrence rates. The study confirms the presence of IED as a strong risk factor for seizure recurrence and the protective effect of ASM. The influence of imaging findings, which have a strong impact on the new definition of epilepsy, could not be confirmed.

Stiripentol in the treatment of adults with focal epilepsy- a retrospective analysis

OBJECTIVES

The aim of the present study was to evaluate the safety and efficacy of the add-on treatment of stiripentol (STP) in adult patients with severely pharmacoresistant focal or multifocal epilepsy.

METHODS

Data on adult patients treated with STP from March 2007 to July 2020 and with at least one clinical follow-up (FU) were retrospectively reviewed. Data on tolerability, efficacy and concomitant medication were evaluated at baseline, 6 months (5.5 ± 1.6 months (mean ± SD)) and 12 months (13.1 ± 3.9 months (mean ± SD)).

RESULTS

Data of 22 patients (54.5% male, mean age 34.4 ± 17.79 years (mean ± SD), including mean duration of epilepsy 17.6 ± 25.5 years (mean ± SD), median seizure frequency 30 ± 20 (median ± MAD) per month, and 63.6% being severely intellectually disabled, with 3 to 18 previous anti-seizure-drugs (ASD), were collected. After 6 months, 72.7% of the patients were still taking STP, and 31% of the patients were responders, including 13% who were seizure-free. The 12-month retention rate was 54.4 %, the response rate was 36.4% and 13.6% of patients were seizure-free at the 12-month FU. Reasons for discontinuation were increased seizure frequency, hyperammonaemia and encephalopathy.

CONCLUSION

STP seems to be a useful option in the treatment of patients with severely pharmacoresistant epilepsy. Prospective trials are necessary to examine the efficacy of STP in adult patients with pharmacoresistant focal epilepsy.

The phenotypic and genotypic spectrum of epilepsy and intellectual disability in adults: Implications for genetic testing

OBJECTIVE

The phenotypic and genotypic spectrum of adult patients with epilepsy and intellectual disability (ID) is less clear than in children. We investigated an adult patient cohort to further elucidate this and inform the genetic testing approach.

METHODS

Fifty-two adult patients (30 male, 22 female) with epilepsy, at least mild ID and no known genetic or acquired cause were included and phenotyped. Variants identified through exome sequencing were evaluated using ACMG criteria. Identified variants were compared with commercially available gene panels. Cluster analysis of two features, age at seizure onset and age at ascertainment of cognitive deficits, was performed.

RESULTS

Median age was 27 years (range 20-57 years) with median seizure onset at 3 years and median ascertainment of cognitive deficits at 1 year. Likely pathogenic/pathogenic variants were identified in 16/52 patients (31%) including 14 (27%) single nucleotide variants and 2 (4%) copy number variants. Simulated yield of commercial gene panels varied between 13% in small (≤144 genes) and 27% in large panels (≥1478 genes). Cluster analysis (optimal number 3 clusters) identified a cluster with early seizure onset and early developmental delay (developmental and epileptic encephalopathy, n = 26), a cluster with early developmental delay but late seizure onset (ID with epilepsy, n = 16) and a third cluster with late ascertainment of cognitive deficits and variable seizure onset (n = 7). The smaller gene panels particularly missed the genes identified in the cluster with early ascertainment of cognitive deficits and later onset of epilepsy (0/4) as opposed to the cluster with developmental and epileptic encephalopathy (7/10).

SIGNIFICANCE

Our data indicates that adult patients with epilepsy and ID represent a heterogeneous cohort that includes grown-up patients with DEE but also patients with primary ID and later onset of epilepsy. To maximize diagnostic yield in this cohort either large gene panels or exome sequencing should be used.

Relationship of left piriform cortex network centrality with temporal lobe epilepsy duration and drug resistance

BACKGROUND

We investigated the relationship of piriform cortex (PC) structural network centrality with drug resistance and epilepsy duration as markers of sustained epileptic activity.

METHODS

PCs were manually delineated on retrospectively collected 3D-T1-MRI images of patients with temporal lobe epilepsy (TLE). Connectomes were computed from diffusion MRI scans, including the PC as network nodes. Betweenness centrality (BC) and node degree were computed and compared across drug-resistant versus drug-sensitive patients. Correlations of centrality metrics with the duration of epilepsy were calculated.

RESULTS

Sixty-two patients (36 females, 43/62 drug-resistant) were included in the main analysis. Greater centrality of the left PC was associated with drug resistance (degree: p = 0.00696, d = 0.85; BC: p = 0.00859, d = 0.59; alpha = 0.0125). Furthermore, left PC centrality was correlated with epilepsy duration (degree: rho = 0.39, p = 0.00181; BC: rho = 0.35, p = 0.0047; alpha = 0.0125). Results were robust to analysis of different parcellation schemes. Exploratory whole-network analysis yielded the largest effects in the left PC. Finer parcellations showed stronger effects for both analyses in the left olfactory cortex rostral to PC. In 28 subjects who had received epilepsy surgery, a trend of smaller centrality in patients with ILAE I outcome was observed in this area.

CONCLUSIONS

We demonstrated an increased centrality of the left PC in patients with drug-resistant TLE, which was also associated with the epilepsy duration. Recurring seizures over long periods may lead to changes of network properties of the PC. Large effects immediately rostral to our delineated PC region suggest a role of olfactory cortex anterior to the limen insulae in epileptogenic networks.

Diffusion magnetic resonance imaging connectome features are predictive of functional lateralization of semantic processing in the anterior temporal lobes

Assessment of regional language lateralization is crucial in many scenarios, but not all populations are suited for its evaluation via task-functional magnetic resonance imaging (fMRI). In this study, the utility of structural connectome features for the classification of language lateralization in the anterior temporal lobes (ATLs) was investigated. Laterality indices for semantic processing in the ATL were computed from task-fMRI in 1038 subjects from the Human Connectome Project who were labeled as stronger rightward lateralized (RL) or stronger leftward to bilaterally lateralized (LL) in a data-driven approach. Data of unrelated subjects (n = 432) were used for further analyses. Structural connectomes were generated from diffusion-MRI tractography, and graph theoretical metrics (node degree, betweenness centrality) were computed. A neural network (NN) and a random forest (RF) classifier were trained on these metrics to classify subjects as RL or LL. After classification, comparisons of network measures were conducted via permutation testing. Degree-based classifiers produced significant above-chance predictions both during cross-validation (NN: AUC-ROC[CI] = 0.68[0.64-0.73], accuracy[CI] = 68.34%[63-73.2%]; RF: AUC-ROC[CI] = 0.7[0.66-0.73], accuracy[CI] = 64.81%[60.9-68.5]) and testing (NN: AUC-ROC[CI] = 0.69[0.53-0.84], accuracy[CI] = 68.09[53.2-80.9]; RF: AUC-ROC[CI] = 0.68[0.53-0.84], accuracy[CI] = 68.09[55.3-80.9]). Comparison of network metrics revealed small effects of increased node degree within the right posterior middle temporal gyrus (pMTG) in subjects with RL, while degree was decreased in the right posterior cingulate cortex (PCC). Above-chance predictions of functional language lateralization in the ATL are possible based on diffusion-MRI connectomes alone. Increased degree within the right pMTG as a right-sided homologue of a known semantic hub, and decreased hubness of the right PCC may form a structural basis for rightward-lateralized semantic processing.

Evaluation of quantitative EEG markers for predicting outcome after the initial treatment with levetiracetam monotherapy in newly diagnosed epilepsy

OBJECTIVE

To develop a predictive model for the classification of seizure freedom under first-line monotherapy with levetiracetam in patients with newly diagnosed epilepsy.

METHODS

Clinical data and routine EEG recordings of patients with newly diagnosed epilepsy who were started on a first-line monotherapy with levetiracetam were analyzed retrospectively. EEG had been acquired prior to the initiation of treatment in all patients. Patients who had experienced no further seizures until the last follow-up were labeled as seizure-free. Spectral EEG features (band power, peak power, and peak frequency) and functional connectivity were computed in each patient and, together with clinical data, formed the input features for the classification procedure. The BiMM-forest algorithm was used for classification and 5-fold cross-validation was conducted to evaluate the model performance.

RESULTS

Seventy-four patients were analyzed (43 (58.1 %) female, 43/74 seizure-free. The mean classification accuracy was 75.5 % (95 %-CI = 46.1-92.4 %). The most predictive features for seizure-freedom were increased right frontal delta energy and delta peak energy as well as decreased central delta energy in the first routine EEG.

SIGNIFICANCE

While significant above-chance predictions were not achieved in this study, a promising framework for the classification of treatment response on first-line monotherapy with levetiracetam based on pre-treatment EEG data alone was provided. Although negative, our results show trends that should encourage future, larger studies to develop EEG-based frameworks for the prediction of treatment response under specific anti-seizure medications.

Increased body mass index (BMI) associated with late epilepsy onset in patients with temporal encephaloceles: a systematic review and analysis of individual patient data

OBJECTIVE

This study investigates the association of Body Mass Index (BMI) and age of epilepsy onset, in patients with epilepsy associated with temporal encephaloceles (TEs).

METHODS

A comprehensive PubMed literature review was conducted using the keywords "temporal encephaloceles" and "epilepsy" for identifying articles for the analysis. Inclusion criteria encompassed all evidence levels reporting patients with TE-related epilepsy and documented BMI. Logistic regression analyses were performed to examine the effect of BMI on predicting epilepsy onset after the 25th year of age. Spearman's correlation assessed the relationship between BMI with epilepsy onset. Finally, the association between BMI and postsurgical outcomes, distinguishing between more favourable outcomes (Engel Class I and II) and less favourable outcomes (Engell Class III and IV) was explored.

RESULTS

Of the initially identified 88 articles, nine were included in the analysis, involving 127 patients with TE-related epilepsy and reported BMI. The mean age of epilepsy onset was 24.9 years (SD = 14.8 years), with a mean BMI of 28.0 kg/m2 (SD = 7.4 kg/m2). A significant positive correlation was observed between BMI and age of epilepsy onset (rho = 0.448, p < 0.001). Female patients had higher BMI compared to male patients (30.1 kg/m2, SD = 8.7 kg/m2 and 26.5 kg/m2, SD = 5.3 kg/m2 respectively, p = 0.008). However, the epilepsy onset did not differ significantly between male and female patients (p = 0.26). The bivariate logistic regression showed that patients with increased BMI were more likely to have an epilepsy onset after the 25th year of age, adjusted for the confounder sex (OR = 1.133, 95%-CI [1.060, 1.211], p < 0.001). Finally, a potential trend indicated a higher average BMI among patients with more favourable postsurgical outcomes than less favourable postsurgical outcomes (27.3 kg/m2, SD = 7.7 kg/m2 and 24.8 kg/m2, SD = 2.2 kg/m2 respectively, p = 0.076).

Verbal memory depends on structural hippocampal subfield volume

Objective

To investigate correlates in hippocampal subfield volume and verbal and visual memory function in patients with temporal lobe epilepsy (TLE), mild amnestic cognitive impairment (MCI) and heathy participants (HP).

Methods

50 right-handed participants were included in this study; 11 patients with temporal lobe epilepsy (TLE), 18 patients with mild amnestic cognitive impairment (MCI) and 21 healthy participants (HP). Verbal memory performance was evaluated via the verbal memory test (VLMT) and visual memory performance via the diagnosticum for cerebral damage (DCM). Hippocampal subfield volumes of T1-weighted Magnetic Resonance Imaging (MRI) scans were computed with FreeSurfer version 7.1. Stepwise correlation analyses were performed between the left hippocampal subfield volumes and learning, free recall, consolidation and recognition performance scores of the VLMT as well as between right hippocampal subfield volumes and visual memory performance.

Results

The volume of the left subicular complex was highly correlated to learning performance (β = 0.284; p = 0.042) and free recall performance in the VLMT (β = 0.434; p = 0.001). The volume of the left CA3 subfield showed a significant correlation to the consolidation performance in the VLMT (β = 0.378; p = 0.006) and recognition performance in the VLMT (β = 0.290; p = 0.037). There was no significant correlation identified between the right hippocampal subfields and the visual memory performance.

Conclusion

The results of this study show verbal memory correlates with hippocampal subfields and support the role of left subiculum and left CA2/CA3 in verbal memory performance.

Psychophysiological interaction analysis for the detection of stimulus-specific networks in reflex epilepsy

We report detailed functional MRI (fMRI) analyses in a patient with reflex seizures elicited by driving along a specific rural crossroad or by watching a video thereof. Semiology consisted of epigastric aura, followed by a sensory seizure of the left hand and sporadic automotor seizures. The right amygdala-region (rh-amygdala) was surgically and electroclinically confirmed as the epileptogenic zone. Presurgical task-fMRI was performed, during which videos of the driving along that specific crossroad (IC), of another crossroad (NC) or noise were presented. Independent component analysis was conducted, and one component was used to aid in selection of a seed region within the rh-amygdala for subsequent psychophysiological interaction analysis (PPI). Here, the following regions showed stronger connectivity with the rh-amygdala seed during the IC condition compared to NC: right > left visual cortex, bilateral insulae, and right secondary somatosensory cortex (S2), potentially explaining epigastric aura and left somatosensory seizure semiology. Contralateral analyses did not reproduce these results. Overall, the ictogenic stimulus elicited enhanced connectivity of the epileptogenic rh-amygdala with visual cortex and further regions of potential seizure spread (S2, insula) as a putative mechanism of ictogenesis. Our results highlight the potential of PPI in the analysis of stimulus-dependent networks in patients with reflex epilepsies to gain insight into seizure generation.

Adult-onset status epilepticus in patients with COQ8A coenzyme Q10 deficiency: A case series

This case series describes the clinical features, diagnostic challenges, treatment approaches, and outcomes of three adult patients with COQ8A-related CoQ10 deficiency presenting with focal status epilepticus, who were effectively treated at the Department of Neurology, Philipps University Marburg, Marburg, Germany. The patients, all from consanguineous families with the first two being siblings, presented with a late onset of the disease, characterized by progressive cerebellar ataxia and epilepsy, with clinical deterioration and focal status epilepticus occurring in adulthood. The first patient exhibited myoclonic status, while the second and third patients presented with bilateral tonic-clonic seizures followed by focal status epilepticus manifesting with cortical blindness. Despite differing semiologies, all patients displayed similar EEG findings with continuous or nearly continuous occipital sharp waves and spikes. MRI findings revealed focal changes in the Diffusion-Weighted Imaging (DWI) and Fluid Attenuated Inversion Recovery (FLAIR) sequences. Significant clinical improvement was observed following treatment with high doses of CoQ10, with the diffusion restriction abnormalities being reversible after therapy. In conclusion, consistent with existing literature, we observed a characteristic EEG pattern that can help identify the disease and facilitate early diagnosis and treatment. The diffusion restriction abnormalities on MRI were reversible after therapy, and high doses of CoQ10 proved beneficial even in cases of status epilepticus.

The impact of the new definition of epilepsy on diagnosis, treatment, and short-term outcomes-A prospective study

Background

In 2014, the ILAE introduced a new definition of epilepsy that allows some patients to be diagnosed earlier than under the previously used definition. According to the old classification, the diagnosis was made after a second unprovoked seizure. The risk of this was 36% after the first seizure. The aim of this study is to investigate the clinical impact of the new definition on diagnosis, treatment, and short-term outcome.

Methods

From 2018 to 2021, adult patients admitted with a first epileptic seizure were prospectively included. Demographic and clinical data were collected at baseline, at 6 and 12 months follow-up (FU). Factors affecting seizure recurrence, especially age, use of anti-seizure medication (ASM), interictal epileptiform discharges (IED) in the EEG, and the presence of structural lesions on imaging were investigated.

Results

Data from 235 patients were collected (41.7% female). Of these, 146 patients (62.1%) were diagnosed with epilepsy (PWE), following the new ILAE-criteria. Potential epileptogenic lesions on imaging were found in 49.3% of PWE. At the first FU (6.08 months ± 1.35), 143 patients (77.3%) were seizure-free, including 89 of the 146 patients diagnosed as PWE were seizure-free (70.6%). At the second FU (12.45 months ± 1.83), 129 patients (80.6%) were seizure-free. Seventy-seven of the PWE were seizure-free (72%). The use of ASM decreased (odds ratio = 0.46, p = 0.004) the recurrence rate significantly.

Conclusion

Our results suggest that the new definition of epilepsy results in a higher frequency of epilepsy diagnosis and treatment. Short-term outcomes improved (1-year-recurrence rate of 19.4%).

First epileptic seizure and quality of life - A prospective study

OBJECTIVE

Impaired QoL and depression are common in patients with chronic epilepsies; however, data on the impact of a first seizure on QoL are sparse. According to the current ILAE-definition of epilepsy, patients may be diagnosed with epilepsy immediately after the first seizure, if EEG and/or imaging findings are abnormal. Patients with normal findings in imaging and EEG are not diagnosed as having epilepsy. We investigated QoL in patients after a first seizure with and without a consecutive diagnosis of epilepsy to detect differences between groups within the first year after seizure.

METHODS

We examined patients (n = 152) after a first epileptic seizure and six and 12 months thereafter using demographic, clinical and QoL-related questionnaire data (Short Form-36 Health Survey (SF-36), Quality of Life in Epilepsy Inventory-31 (QOLIE-31), Beck's depression inventory II (BDI-II)).

RESULTS

Patients diagnosed with epilepsy after the first seizure showed a tendency of reduced mental health-related QoL six (p =.098) and 12 months (p =.092) after the first seizure compared to patients who were not diagnosed with epilepsy, but were diagnosed as having had a single first seizure. There were no significant differences between the two groups in physical health-related QoL. Multiple regression analyses showed that especially depressive symptoms explained 22.0 - 48.7 % of the variance in mental health-related QoL six (p <.001) and 12 months (p <.001) after the first seizure. Physical health-related QoL was especially predicted by age (p <.001), group (p =.002) and recurrent seizures (p = < 0.001). In PWE, there was a statistical trend with improving QOLIE-31 overall scores from six to 12 months (p =.086).

CONCLUSION

Our results suggest that QoL may be impaired in patients diagnosed with epilepsy early, immediately after the onset of disease. Early follow-up monitoring from the beginning of patient career is important for possible interventions and to improve patients' daily life in the long term.

The connectivity-based architecture of the human piriform cortex

The anatomy of the human piriform cortex (PC) is poorly understood. We used a bimodal connectivity-based-parcellation approach to investigate subregions of the PC and its connectional differentiation from the amygdala. One hundred (55 % female) genetically unrelated subjects from the Human Connectome Project were included. A region of interest (ROI) was delineated bilaterally covering PC and amygdala, and functional and structural connectivity of this ROI with the whole gray matter was computed. Spectral clustering was performed to obtain bilateral parcellations at granularities of k = 2-10 clusters and combined bimodal parcellations were computed. Validity of parcellations was assessed via their mean individual-to-group similarity per adjusted rand index (ARI). Individual-to-group similarity was higher than chance in both modalities and in all clustering solutions. The amygdala was clearly distinguished from PC in structural parcellations, and olfactory amygdala was connectionally more similar to amygdala than to PC. At higher granularities, an anterior and ventrotemporal and a posterior frontal cluster emerged within PC, as well as an additional temporal cluster at their boundary. Functional parcellations also showed a frontal piriform cluster, and similar temporal clusters were observed with less consistency. Results from bimodal parcellations were similar to the structural parcellations. Consistent results were obtained in a validation cohort. Distinction of the human PC from the amygdala, including its olfactory subregions, is possible based on its structural connectivity alone. The canonical fronto-temporal boundary within PC was reproduced in both modalities and with consistency. All obtained parcellations are freely available.