Showing papers in "Epilepsia in 2014"

ILAE Official Report: A practical clinical definition of epilepsy

Abstract: Epilepsy was defined conceptually in 2005 as a disorder of the brain characterized by an enduring predisposition to generate epileptic seizures. This definition is usually practically applied as having two unprovoked seizures >24 h apart. The International League Against Epilepsy (ILAE) accepted recommendations of a task force altering the practical definition for special circumstances that do not meet the two unprovoked seizures criteria. The task force proposed that epilepsy be considered to be a disease of the brain defined by any of the following conditions: (1) At least two unprovoked (or reflex) seizures occurring >24 h apart; (2) one unprovoked (or reflex) seizure and a probability of further seizures similar to the general recurrence risk (at least 60%) after two unprovoked seizures, occurring over the next 10 years; (3) diagnosis of an epilepsy syndrome. Epilepsy is considered to be resolved for individuals who either had an age-dependent epilepsy syndrome but are now past the applicable age or who have remained seizure-free for the last 10 years and off antiseizure medicines for at least the last 5 years. "Resolved" is not necessarily identical to the conventional view of "remission or "cure." Different practical definitions may be formed and used for various specific purposes. This revised definition of epilepsy brings the term in concordance with common use. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here.

Cannabidiol: pharmacology and potential therapeutic role in epilepsy and other neuropsychiatric disorders.

Abstract: To present a summary of current scientific evidence about the cannabinoid, cannabidiol (CBD) with regard to its relevance to epilepsy and other selected neuropsychiatric disorders. We summarize the presentations from a conference in which invited participants reviewed relevant aspects of the physiology, mechanisms of action, pharmacology, and data from studies with animal models and human subjects. Cannabis has been used to treat disease since ancient times. Δ(9) -Tetrahydrocannabinol (Δ(9) -THC) is the major psychoactive ingredient and CBD is the major nonpsychoactive ingredient in cannabis. Cannabis and Δ(9) -THC are anticonvulsant in most animal models but can be proconvulsant in some healthy animals. The psychotropic effects of Δ(9) -THC limit tolerability. CBD is anticonvulsant in many acute animal models, but there are limited data in chronic models. The antiepileptic mechanisms of CBD are not known, but may include effects on the equilibrative nucleoside transporter; the orphan G-protein-coupled receptor GPR55; the transient receptor potential of vanilloid type-1 channel; the 5-HT1a receptor; and the α3 and α1 glycine receptors. CBD has neuroprotective and antiinflammatory effects, and it appears to be well tolerated in humans, but small and methodologically limited studies of CBD in human epilepsy have been inconclusive. More recent anecdotal reports of high-ratio CBD:Δ(9) -THC medical marijuana have claimed efficacy, but studies were not controlled. CBD bears investigation in epilepsy and other neuropsychiatric disorders, including anxiety, schizophrenia, addiction, and neonatal hypoxic-ischemic encephalopathy. However, we lack data from well-powered double-blind randomized, controlled studies on the efficacy of pure CBD for any disorder. Initial dose-tolerability and double-blind randomized, controlled studies focusing on target intractable epilepsy populations such as patients with Dravet and Lennox-Gastaut syndromes are being planned. Trials in other treatment-resistant epilepsies may also be warranted. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here.

Two‐year seizure reduction in adults with medically intractable partial onset epilepsy treated with responsive neurostimulation: Final results of the RNS System Pivotal trial

Abstract: SummaryObjective To demonstrate the safety and effectiveness of responsive stimulation at the seizure focus as an adjunctive therapy to reduce the frequency of seizures in adults with medically intractable partial onset seizures arising from one or two seizure foci. Methods Randomized multicenter double-blinded controlled trial of responsive focal cortical stimulation (RNS System). Subjects with medically intractable partial onset seizures from one or two foci were implanted, and 1 month postimplant were randomized 1:1 to active or sham stimulation. After the fifth postimplant month, all subjects received responsive stimulation in an open label period (OLP) to complete 2 years of postimplant follow-up. Results All 191 subjects were randomized. The percent change in seizures at the end of the blinded period was −37.9% in the active and −17.3% in the sham stimulation group (p = 0.012, Generalized Estimating Equations). The median percent reduction in seizures in the OLP was 44% at 1 year and 53% at 2 years, which represents a progressive and significant improvement with time (p < 0.0001). The serious adverse event rate was not different between subjects receiving active and sham stimulation. Adverse events were consistent with the known risks of an implanted medical device, seizures, and of other epilepsy treatments. There were no adverse effects on neuropsychological function or mood. Significance Responsive stimulation to the seizure focus reduced the frequency of partial-onset seizures acutely, showed improving seizure reduction over time, was well tolerated, and was acceptably safe. The RNS System provides an additional treatment option for patients with medically intractable partial-onset seizures.

Sudden unexpected death in epilepsy: assessing the public health burden.

Abstract: SummaryObjective There is not yet a clear consensus on the incidence of sudden unexpected death in epilepsy (SUDEP) or the extent of its burden on public health. In this systematic review, we seek to summarize the incidence of SUDEP and its age distribution, as well as the years of potential life lost and cumulative risks of SUDEP for persons with epilepsy. Methods We conducted a systematic search for epidemiologic studies of sudden death in epilepsy and rated their quality of evidence. We pooled data from comparable higher quality population-based studies of SUDEP incidence across all age groups, calculating the overall incidence of SUDEP per 100,000 population, and per 1,000 people with epilepsy. Using standard formulas, we also calculated the years of potential life lost and cumulative risks associated with SUDEP. Results SUDEP has an estimated overall crude annual incidence rate of 0.81 cases per 100,000 population, or 1.16 cases per 1,000 patients with epilepsy. Comparing years of potential life lost from SUDEP with selected other neurologic diseases, SUDEP ranks second only to stroke. Significance Despite limitations to the data on which our analysis is based, we conclude that the public health burden of SUDEP, which has previously been underappreciated, is substantial and deserves much more attention from clinicians, researchers, and the public health community. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here.

The case for medical marijuana in epilepsy.

Abstract: Charlotte, a little girl with SCN1A-confirmed Dravet syndrome, was recently featured in a special that aired on CNN. Through exhaustive personal research and assistance from a Colorado-based medical marijuana group (Realm of Caring), Charlotte's mother started adjunctive therapy with a high concentration cannabidiol/Δ(9) -tetrahydrocannabinol (CBD:THC) strain of cannabis, now known as Charlotte's Web. This extract, slowly titrated over weeks and given in conjunction with her existing antiepileptic drug regimen, reduced Charlotte's seizure frequency from nearly 50 convulsive seizures per day to now 2-3 nocturnal convulsions per month. This effect has persisted for the last 20 months, and Charlotte has been successfully weaned from her other antiepileptic drugs. We briefly review some of the history, preclinical and clinical data, and controversies surrounding the use of medical marijuana for the treatment of epilepsy, and make a case that the desire to isolate and treat with pharmaceutical grade compounds from cannabis (specifically CBD) may be inferior to therapy with whole plant extracts. Much more needs to be learned about the mechanisms of antiepileptic activity of the phytocannabinoids and other constituents of Cannabis sativa.

Brivaracetam as adjunctive treatment for uncontrolled partial epilepsy in adults: a phase III randomized, double-blind, placebo-controlled trial.

Abstract: SummaryPurpose Brivaracetam (BRV) is a novel high-affinity synaptic vesicle protein 2A ligand currently being investigated for the treatment of epilepsy. The purpose of this phase III study was to evaluate the efficacy and safety/tolerability of adjunctive BRV in adults with uncontrolled partial-onset (focal) seizures. Methods This was a prospective, multicenter, randomized, double-blind, placebo-controlled, parallel-group, fixed-dose trial (N01253; NCT00464269). Adults aged 16–70 years with well-characterized partial epilepsy not fully controlled despite treatment with one or two antiepileptic drugs (AEDs) were enrolled. Patients who experienced eight or more partial-onset seizures, whether or not secondarily generalized, during the 8-week prospective baseline period were randomized (1:1:1:1) to receive twice-daily placebo (PBO) or BRV (5, 20, or 50 mg/day) without titration. The primary efficacy endpoint was percent reduction over PBO in baseline-adjusted partial-onset seizure frequency/week during the 12-week treatment period. Comparison of BRV with PBO was sequential (50, 20 mg/day, then 5 mg/day). Secondary endpoints included ≥50% responder rate and median percent reduction from baseline in partial-onset seizure frequency/week. Post hoc analyses included the primary efficacy endpoint evaluated over 28 days and exploratory subanalyses of efficacy by seizure subtype. Safety and tolerability assessments included treatment-emergent adverse events (TEAEs), laboratory tests, electrocardiography, vital signs, and physical and neurologic examinations. Key Findings Of 400 patients randomized, 396 were included in the intent-to-treat (ITT) population (PBO n = 98, BRV 5 mg/day n = 97, BRV 20 mg/day n = 100, BRV 50 mg/day n = 101) and 392 comprised the modified ITT (mITT) population. A total of 361 (91.2%) of 396 patients completed the study. Most patients (78.3%) were receiving two concomitant AEDs. Percent reduction in partial-onset seizure frequency/week over PBO was −0.9% (p = 0.885) for BRV 5 mg/day, 4.1% (p = 0.492) for BRV 20 mg/day, and 12.8% (p = 0.025) for BRV 50 mg/day (mITT population). Statistical significance was also achieved for the percent reduction over PBO in baseline-adjusted partial-onset seizure frequency/28 days for BRV 50 mg/day (22.0%; p = 0.004) but not for the other BRV dose groups. In the BRV 50 mg/day group, statistical significance was also seen for the ≥50% responder rate (BRV 32.7% vs. PBO 16.7%; p = 0.008) and median percent reduction from baseline in partial-onset seizure frequency/week (BRV 30.5% vs. PBO 17.8%; p = 0.003). In the exploratory subanalysis by seizure subtype, median percent reduction from baseline in seizure frequency/week and ≥50% responder rate were numerically greater than PBO in the BRV 20 and 50 mg/day groups for simple partial, complex partial, and secondarily generalized seizures. BRV was generally well tolerated, with the majority of TEAEs being mild-to-moderate in intensity. Of the TEAEs reported by ≥5% patients, those with a frequency >3% higher than PBO for any dose of BRV compared with PBO were somnolence, dizziness, fatigue, influenza, insomnia, nasopharyngitis, vomiting, diarrhea, urinary tract infection, and nausea. Significance Adjunctive BRV at a daily dose of 50 mg was associated with statistically significant reductions in seizure frequency compared with PBO. All doses of BRV showed good tolerability throughout the study.

Functional connectivity of hippocampal networks in temporal lobe epilepsy

Abstract: Objective Temporal Lobe Epilepsy (TLE) affects brain areas beyond the temporal lobes due to connections of the hippocampi and other temporal lobe structures. Using functional connectivity MRI, we determined the changes of hippocampal networks in TLE to assess for a more complete distribution of abnormality.

Adjunctive brivaracetam in adults with uncontrolled focal epilepsy: results from a double-blind, randomized, placebo-controlled trial.

Abstract: Summary Purpose Brivaracetam (BRV) is a novel high-affinity synaptic vesicle protein 2A ligand in clinical development for the treatment of epilepsy. This phase III study (N01252; NCT00490035) evaluated the efficacy and safety/tolerability of BRV (20, 50, and 100 mg/day) compared with placebo (PBO) in patients aged 16–70 years with uncontrolled focal seizures with/without secondary generalization, despite treatment with one to two concomitant antiepileptic drugs at a stable and optimal dosage. Methods This was a double-blind, randomized, placebo-controlled trial conducted across Europe and India. Eligible patients had two or more focal seizures/month for 3 months prior to screening and eight or more focal seizures during the 8-week prospective baseline. Concomitant use of levetiracetam was limited to 20% of randomized patients. Patients were randomized (1:1:1:1) to BRV 20, 50, 100 mg/day or PBO with no up-titration for 12 weeks, followed by down-titration or entry into a long-term follow-up study. The primary efficacy end point was percent reduction over PBO in baseline-adjusted focal seizure frequency/week over the 12-week treatment period. Comparison of BRV with PBO was sequential to control for multiplicity (50, 100, 20 mg/day), and thus required BRV to demonstrate superiority over PBO at 50 mg/day to meet the primary efficacy end point. Secondary efficacy variables were median percent reduction from baseline in focal seizure frequency/week, ≥50% responder rate, and seizure freedom (all seizure types). Safety assessments included treatment-emergent adverse events (TEAEs). Key Findings Of 399 randomized patients, 398 were included in the intent-to-treat (ITT) and safety populations. Overall, 367 (92.2%) of 398 patients completed the study (BRV: 93.9%, 88.9%, and 94.0% for 20, 50, and 100 mg/day, respectively; PBO: 92.0%) and 345 (86.7%) of 398 patients continued into long-term follow-up studies (BRV: 87.9%, 82.8%, and 88.0% for 20, 50, and 100 mg/day, respectively; PBO: 88.0%). The study did not meet its primary efficacy end point based on the predefined sequential testing strategy. Indeed, percent reduction over PBO in baseline-adjusted focal seizure frequency/week (primary efficacy analysis) was 6.8% (p = 0.239), 6.5% (p = 0.261), and 11.7% (p = 0.037) for BRV 20, 50, and 100 mg/day, respectively. Median percent reduction from baseline in focal seizure frequency/week was 30.0% (p = 0.019), 26.8% (p = 0.092), and 32.5% (p = 0.004) for BRV 20, 50, and 100 mg/day, respectively, compared with 17.0% for PBO. Responder rates (≥50%) were 27.3% (p = 0.339), 27.3% (p = 0.372), and 36.0% (p = 0.023) for BRV 20, 50, and 100 mg/day, respectively, compared with 20.0% for PBO. Complete seizure freedom was reported by 2/99, 0/99, and 4/100 patients on BRV 20, 50, and 100 mg/day, respectively, compared with 0/100 on PBO. The incidence of TEAEs was higher for BRV 20 (56/99, 56.6%), 50 (62/99, 62.6%), and 100 mg/day (63/100, 63.0%) than PBO (53/100, 53.0%); most TEAEs were mild or moderate in severity. The most frequently reported TEAEs in the BRV groups were headache, somnolence, dizziness, and fatigue. Significance In this study of adjunctive BRV (20–100 mg/day) in adults with uncontrolled focal seizures, the primary efficacy analysis based on the 50 mg/day dose was not statistically significant. However, BRV 100 mg/day reduced baseline-adjusted focal seizure frequency/week by 11.7% over PBO, achieving statistical significance (p = 0.037). Secondary efficacy analyses (percent reduction from baseline in focal seizure frequency/week, ≥50% responder rate) provided supportive evidence for the efficacy of BRV 100 mg/day. BRV 20–100 mg/day was well tolerated without up-titration, with a high completion rate.

Vagus nerve stimulation for drug‐resistant epilepsy: A European long‐term study up to 24 months in 347 children

Abstract: SummaryObjective To gain insight into the long-term impact of vagus nerve stimulation (with VNS Therapy) in children with drug-resistant epilepsy, we conducted the largest retrospective multicenter study to date over an extended follow-up period of up to 24 months. Methods The primary objective was to assess change in seizure frequency of the predominant seizure type (defined as the most disabling seizure) following VNS device implantation. Treating physicians collected data from patient records from baseline to 6, 12, and 24 months of follow-up. Results The analysis population included 347 children (aged 6 months to 17.9 years at the time of implant). At 6, 12, and 24 months after implantation, 32.5%, 37.6%, and 43.8%, respectively, of patients had ≥50% reduction in baseline seizure frequency of the predominant seizure type. The responder rate was higher in a subgroup of patients who had no change in antiepileptic drugs (AEDs) during the study. Favorable results were also evident for all secondary outcome measures including changes in seizure duration, ictal severity, postictal severity, quality of life, clinical global impression of improvement, and safety. Post hoc analyses demonstrated a statistically significant correlation between VNS total charge delivered per day and an increase in response rate. VNS Therapy is indicated as adjunctive therapy in children with focal, structural epilepsies, who for any reason are not good candidates for surgical treatment following the trial of two or more AEDs. Children with predominantly generalized seizures from genetic, structural epilepsies, like Dravet syndrome or Lennox-Gastaut syndrome, could also benefit from VNS Therapy. Significance The results demonstrate that adjunctive VNS Therapy in children with drug-resistant epilepsy reduces seizure frequency and is well tolerated over a 2-year follow-up period. No new safety issues were identified. A post hoc analysis revealed a dose–response correlation for VNS in patients with epilepsy.

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

Abstract: 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.

Frontal lobe seizures: From clinical semiology to localization

Abstract: SummaryObjective Frontal lobe seizures are difficult to characterize according to semiologic and electrical features. We wished to establish whether different semiologic subgroups can be identified and whether these relate to anatomic organization. Methods We assessed all seizures from 54 patients with frontal lobe epilepsy that were explored with stereoelectroencephalography (SEEG) during presurgical evaluation. Semiologic features and concomitant intracerebral EEG changes were documented and quantified. These variables were examined using Principal Component Analysis and Cluster Analysis, and semiologic features correlated with anatomic localization. Results Four main groups of patients were identified according to semiologic features, and correlated with specific patterns of anatomic seizure localization. Group 1 was characterized clinically by elementary motor signs and involved precentral and premotor regions. Group 2 was characterized by a combination of elementary motor signs and nonintegrated gestural motor behavior, and involved both premotor and prefrontal regions. Group 3 was characterized by integrated gestural motor behavior with distal stereotypies and involved anterior lateral and medial prefrontal regions. Group 4 was characterized by seizures with fearful behavior and involved the paralimbic system (ventromedial prefrontal cortex ± anterior temporal structures). The groups were organized along a rostrocaudal axis, representing bands within a spectrum rather than rigid categories. The more anterior the seizure organization, the more likely was the occurrence of integrated behavior during seizures. Distal stereotypies were associated with the most anterior prefrontal localizations, whereas proximal stereotypies occurred in more posterior prefrontal regions. Significance Meaningful categorization of frontal seizures in terms of semiology is possible and correlates with anatomic organization along a rostrocaudal axis, in keeping with current hypotheses of frontal lobe hierarchical organization. The proposed electroclinical categorization offers pointers as to the likely zone of organization of networks underlying semiologic production, thus aiding presurgical localization. Furthermore, analysis of ictal motor behavior in prefrontal seizures, including stereotypies, leads to deciphering the cortico-subcortical networks that produce such behaviors.

Effects of epilepsy treatments on sleep architecture and daytime sleepiness: An evidence‐based review of objective sleep metrics

Abstract: SummaryObjective Sleep is considered restorative, and good quantity and quality sleep is required for memory consolidation and synaptic plasticity. Sleep disorders are common in patients with epilepsy. Poor sleep quality or quantity may worsen seizure control. On the other end, seizures and epilepsy may worsen the sleep quality and set a vicious cycle. In addition, antiepileptic drugs have an effect on sleep architecture. We performed a systemic literature review with a goal to evaluate the effect of antiepileptic drugs and nondrug treatments for epilepsy on sleep architecture to help better understand treatment effects, especially in patients with epilepsy and sleep problems. Methods We searched PubMed and identified studies that evaluated objective sleep outcomes for an antiepileptic drug. We also searched for studies with objective sleep outcomes that evaluated other epilepsy treatments such as epilepsy surgery, vagus nerve stimulation, and ketogenic diet. Results The studies were categorized based on evidence class and study population for an individual antiepileptic drug or treatment. We identified that most antiepileptic drugs and nondrug treatments for epilepsy affect sleep architecture. Significance We identified that gabapentin, tiagabine, pregabalin, clobazam, and carbamazepine reduce sleep latency and/or improve sleep efficiency. Phenobarbital, valproic acid, and higher-dose levetiracetam aggravate daytime sleepiness, whereas topiramate and zonisamide do not. Vagus nerve stimulation reduces daytime sleepiness, and ketogenic diet improves slow-wave sleep. Epilepsy surgery may improve nocturnal sleep only in a subgroup of patients with improved seizure frequency. Further studies are needed to evaluate the dose-dependent sleep effects of antiepileptic drugs and nondrug treatments independent of the improvement of epilepsy, and to identify if these changes are clinically significant.

Diagnostic test utilization in evaluation for resective epilepsy surgery in children

Abstract: Epilepsy surgery is highly successful in achieving seizure freedom in carefully selected children with drug-resistant focal epilepsy. Advances in technology have aided presurgical evaluation and increased the number of possible candidates. Many of the tests employed are resource intense, and in specific cases they may be unhelpful or have adverse effects. Some standardization of the evaluation process is thus considered timely. Given the lack of class 1 or 2 evidence defining the relative utility of each test in specific clinicopathologic cohorts, a set of expert recommendations was attempted using consensus among members of the Pediatric Epilepsy Surgery Task Force of the International League Against Epilepsy (ILAE) Commissions of Pediatrics and Diagnostics These recommendations aim to limit fringe over or underutilization of use while retaining substantial flexibility in the use of various tests, in keeping with most standard practices at established pediatric epilepsy centers. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here.

IL‐1β associations with posttraumatic epilepsy development: A genetics and biomarker cohort study

Abstract: Summary Objective Posttraumatic epilepsy (PTE) is a significant complication following traumatic brain injury (TBI), yet the role of genetic variation in modulating PTE onset is unclear. We hypothesized that TBI-induced inflammation likely contributes to seizure development. We assessed whether genetic variation in the interleukin-1beta (IL-1β) gene, IL-1β levels in cerebrospinal fluid (CSF) and serum, and CSF/serum IL-1β ratios would predict PTE development post-TBI. Methods We investigated PTE development in 256 Caucasian adults with moderate-to-severe TBI. IL-1β tagging and functional single nucleotide polymorphisms (SNPs) were genotyped. Genetic variance and PTE development were assessed. Serum and CSF IL-1β levels were collected from a subset of subjects (n = 59) during the first week postinjury and evaluated for their associations with IL-1β gene variants, and also PTE. Temporally matched CSF/serum IL-1β ratios were also generated to reflect the relative contribution of serum IL-1β to CSF IL-1β. Results Multivariate analysis showed that higher CSF/serum IL-1β ratios were associated with increased risk for PTE over time (p = 0.008). Multivariate analysis for rs1143634 revealed an association between the CT genotype and increased PTE risk over time (p = 0.005). The CT genotype group also had lower serum IL-1β levels (p = 0.014) and higher IL-1β CSF/serum ratios (p = 0.093). Significance This is the first report implicating IL-1β gene variability in PTE risk and linking (1) IL-1β gene variation with serum IL-1β levels observed after TBI and (2) IL-1β ratios with PTE risk. Given these findings, we propose that genetic and IL-1β ratio associations with PTE may be attributable to biologic variability with blood–brain barrier integrity during TBI recovery. These results provide a rationale for further studies (1) validating the impact of genetic variability on IL-1β production after TBI, (2) assessing genetically mediated signaling mechanisms that contribute to IL-1β CSF/serum associations with PTE, and (3) evaluating targeted IL-1β therapies that reduce PTE. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here.

Cyclooxygenase-2 in epilepsy.

Abstract: Epilepsy is one of the more prevalent neurologic disorders in the world, affecting approximately 50 million people of different ages and backgrounds. Epileptic seizures propagating through both lobes of the forebrain can have permanent debilitating effects on a patient's cognitive and somatosensory brain functions. Epilepsy, defined by the sporadic occurrence of spontaneous recurrent seizures (SRS), is often accompanied by inflammation of the brain. Pronounced increases in the expression of key inflammatory mediators (e.g., interleukin -1β [IL-1β], tumor necrosis factor alpha [TNFα], cyclooxygenase-2 [COX-2], and C-X-C motif chemokine 10 [CXCL10]) after seizures may cause secondary damage in the brain and increase the likelihood of repetitive seizures. The COX-2 enzyme is induced rapidly during seizures. The increased level of COX-2 in specific areas of the epileptic brain can help to identify regions of seizure-induced brain inflammation. A good deal of effort has been expended to determine whether COX-2 inhibition might be neuroprotective and represent an adjunct therapeutic strategy along with antiepileptic drugs used to treat epilepsy. However, the effectiveness of COX-2 inhibitors on epilepsy animal models appears to depend on the timing of administration. With all of the effort placed on making use of COX-2 inhibitors as therapeutic agents for the treatment of epilepsy, inflammation, and neurodegenerative diseases there has yet to be a selective and potent COX-2 inhibitor that has shown a clear therapeutic outcome with acceptable side effects.

Early onset epileptic encephalopathy caused by de novo SCN8A mutations.

Abstract: SummaryObjective De novo SCN8A mutations have been reported in patients with epileptic encephalopathy. Herein we report seven patients with de novo heterozygous SCN8A mutations, which were found in our comprehensive genetic analysis (target capture or whole-exome sequencing) for early onset epileptic encephalopathies (EOEEs). Methods A total of 163 patients with EOEEs without mutations in known genes, including 6 with malignant migrating partial seizures in infancy (MMPSI), and 60 with unclassified EOEEs, were analyzed by target capture (28 samples) or whole-exome sequencing (135 samples). Results We identified de novo SCN8A mutations in 7 patients: 6 of 60 unclassified EOEEs (10.0%), and one of 6 MMPSI cases (16.7%). The mutations were scattered through the entire gene: four mutations were located in linker regions, two in the fourth transmembrane segments, and one in the C-terminal domain. The type of the initial seizures was variable including generalized tonic–clonic, atypical absence, partial, apneic attack, febrile convulsion, and loss of tone and consciousness. Onset of seizures was during the neonatal period in two patients, and between 3 and 7 months of age in five patients. Brain magnetic resonance imaging (MRI) showed cerebellar and cerebral atrophy in one and six patients, respectively. All patients with SCN8A missense mutations showed initially uncontrollable seizures by any drugs, but eventually one was seizure-free and three were controlled at the last examination. All patients showed developmental delay or regression in infancy, resulting in severe intellectual disability. Significance Our data reveal that SCN8A mutations can cause variable phenotypes, most of which can be diagnosed as unclassified EOEEs, and rarely as MMPSI. Together with previous reports, our study further indicates that genetic testing of SCN8A should be considered in children with unclassified severe epilepsy. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here.

Interrater agreement for Critical Care EEG Terminology.

Abstract: Objective The interpretation of critical care electroencephalography (EEG) studies is challenging because of the presence of many periodic and rhythmic patterns of uncertain clinical significance. Defining the clinical significance of these patterns requires standardized terminology with high interrater agreement (IRA). We sought to evaluate IRA for the final, published American Clinical Neurophysiology Society (ACNS)–approved version of the critical care EEG terminology (2012 version). Our evaluation included terms not assessed previously and incorporated raters with a broad range of EEG reading experience.

SUDEP and epilepsy-related mortality in pregnancy.

Abstract: Although data are limited, research in 2004 estimated a 10-fold increase in mortality in pregnancy in the United Kingdom in women with epilepsy (WWE) compared to women without epilepsy. We highlight epilepsy mortality in pregnancy based on the 2011 report of the United Kingdom Confidential Enquiries into Maternal Deaths, relating its findings to previous reports and epilepsy-rates in pregnancy. Among 2,291,493 maternities (2006-2008), we estimated 0.6% or 13,978 were in WWE. Fourteen deaths were epilepsy-related, of which 11 (79%) were sudden and unexpected (SUDEP). Nine occurred during pregnancy and five were postpartum. Nine (64%) were in women taking lamotrigine, seven as monotherapy. We estimated that 1:1,000 women died from epilepsy (mostly SUDEP) during or shortly after pregnancy. Epilepsy-related mortality is a significant risk in pregnancy. Antiepileptic drug-related factors may be relevant. The high proportion of women taking lamotrigine may reflect United Kingdom prescribing practice. Recent observations from the European and International Registry of Antiepileptic Drugs and Pregnancy (EURAP), whereby women on lamotrigine, the levels of which significantly decrease in pregnancy, had more difficulties with epilepsy control, argue against this being the sole explanation. Given the potential risks, every attempt should be made to prevent seizures, particularly convulsive, during pregnancy and postpartum. This, we believe, includes being proactive in maintaining lamotrigine levels during pregnancy.

Adjunctive brivaracetam for uncontrolled focal and generalized epilepsies: results of a phase III, double-blind, randomized, placebo-controlled, flexible-dose trial.

Abstract: PurposeTo evaluate the safety and tolerability of adjunctive brivaracetam (BRV), a high-affinity synaptic vesicle protein 2A (SV2A) ligand, in adults with uncontrolled epilepsy. Efficacy was also assessed in patients with focal seizures as a secondary objective, and explored by descriptive analysis in patients with generalized seizures. MethodsThis was a phase III, randomized, double-blind, placebo (PBO)-controlled flexible dose trial (N01254/NCT00504881) in adults (16-70years) with uncontrolled epilepsy (up to 20% could be patients with generalized epilepsy). After a prospective 4-week baseline, patients were randomized (3:1) to b.i.d. BRV or PBO, initiated at 20mg/day and increased, as needed, to 150mg/day during an 8-week dose-finding period. This was followed by an 8-week stable-dose maintenance period. The treatment period comprised the dose-finding period plus the maintenance period (16weeks). Key FindingsA total of 480 patients were randomized (BRV 359, PBO 121); of these, 431 had focal epilepsy and 49 had generalized epilepsy. Ninety percent BRV- and 91.7% PBO-treated patients completed the study. Similar proportions of patients (BRV 66.0%, PBO 65.3%) reported adverse events (AEs) during the treatment period. AEs led to treatment discontinuation in 6.1% and 5.0% of BRV- and PBO-treated patients, respectively. The incidence of AEs declined from the dose-finding (BRV 56.0%, PBO 55.4%) to the maintenance (BRV 36.8%, PBO 40.9%) period. The most frequent AEs during the treatment period were headache (BRV 14.2% vs. PBO 19.8%), somnolence (BRV 11.1% vs. PBO 4.1%), and dizziness (BRV 8.6% vs. PBO 5.8%). The incidence of psychiatric AEs was similar for BRV and PBO (BRV 12.3%, PBO 11.6%). In patients with focal seizures, the baseline-adjusted percent reduction in seizure frequency/week in the BRV group (n=323) over PBO (n=108) was 7.3% (p=0.125) during the treatment period. The median percent reduction in baseline-adjusted seizure frequency/week was 26.9% BRV versus 18.9% PBO (p=0.070), and the 50% responder rate was 30.3% BRV versus 16.7% PBO (p=0.006). In patients with generalized seizures only, the number of seizure days/week decreased from 1.42 at baseline to 0.63 during the treatment period in BRV-treated patients (n=36), and from 1.47 at baseline to 1.26 during the treatment period in PBO-treated patients (n=13). The median percent reduction from baseline in generalized seizure days/week was 42.6% versus 20.7%, and the 50% responder rate was 44.4% versus 15.4% in BRV-treated and PBO-treated patients, respectively. SignificanceAdjunctive BRV given at individualized tailored doses (20-150mg/day) was well tolerated in adults with uncontrolled epilepsy, and our results provided support for further evaluation of efficacy in reducing focal and generalized seizures.

An unknown quantity—The worldwide prevalence of epilepsy

Abstract: The reported incidence (rate of new cases in a population) of epilepsy is consistently lower in high-income than in lower-income economies, whereas opinions vary regarding comparative prevalence rates (proportion of the population with epilepsy). For any condition that does not influence mortality, lifetime prevalence should approximate to the cumulative incidence. We suspected that epilepsy prevalence might be uniform throughout the world, whereas incidence is higher in resource-poor countries. To test whether our suspicion was reasonable, we conducted a Medline search to estimate the prevalence of active and lifetime epilepsy in different economic areas throughout the world. We found that the range of estimated prevalence of epilepsy may be broadly similar throughout the world, but comparison is limited by lack of door-to-door studies in high-income economies and by variations in the definitions of active epilepsy. We contend that any inconsistencies between incidence and prevalence are due largely to the excess premature death rate in people with epilepsy in lower-income economies. Much of the variability in epidemiologic indices arises from differences in study methodology, definitions, and risk factors. The epidemiology of epilepsy, and particularly its mortality, needs thorough investigation using uniform definitions that do not include antiepileptic drug use; causes of death should be identified and actions, including treatment and education, should be taken to avoid preventable deaths.

The long-term effect of vagus nerve stimulation on quality of life in patients with pharmacoresistant focal epilepsy: the PuLsE (Open Prospective Randomized Long-term Effectiveness) trial.

Abstract: Objective To evaluate whether vagus nerve stimulation (VNS) as adjunct to best medical practice (VNS + BMP) is superior to BMP alone in improving long-term health-related quality of life (HRQoL). Methods PuLsE (Open Prospective Randomized Long-term Effectiveness) was a prospective, randomized, parallel-group, open-label, and long-term effectiveness study (conducted at 28 sites in Europe and Canada). Adults with pharmacoresistant focal seizures (n = 112) received VNS + BMP or BMP (1:1 ratio). Medications and VNS parameters could be adjusted as clinically indicated for optimal seizure control while minimizing adverse effects. Primary endpoint was mean change from baseline HRQoL (using Quality of Life in Epilepsy Inventory-89 total score; QOLIE-89). Secondary endpoints included changes in seizure frequency, responder rate (≥50% decrease in seizure frequency), Centre for Epidemiologic Studies Depression scale (CES-D), Neurological Disorders Depression Inventory-Epilepsy scale (NDDI-E), Clinical Global Impression-Improvement scale (CGI-I), Adverse Event Profile (AEP), and antiepileptic drug (AED) load. The study was prematurely terminated due to recruitment difficulties prior to completing the planned enrollment of n = 362. Results for n = 96 who had baseline and at least one follow-up QOLIE-89 assessment (from months 3-12) were included in this analysis. Mixed model repeated measures (MMRM) analysis of variance was performed on change from baseline for the primary and secondary endpoints.

Pharmacotherapeutic targeting of cation-chloride cotransporters in neonatal seizures

Abstract: SUMMARY Seizures are a common manifestation of acute neurologic insults in neonates and are often resistant to the standard antiepileptic drugs that are efficacious in children and adults. The paucity of evidence-based treatment guidelines, coupled with a rudimentary understanding of disease pathogenesis, has made the current treatment of neonatal seizures empiric and often ineffective, highlighting the need for novel therapies. Key developmental differences in c-aminobutyric acid (GABA)ergic neurotransmission between the immature and mature brain, and trauma-induced alterations in the function of the cation-chloride cotransporters (CCCs) NKCC1 and KCC2, probably contribute to the poor efficacy of standard antiepileptic drugs used in the treatment of neonatal seizures. Although CCCs are attractive drug targets, bumetanide and other existing CCC inhibitors are suboptimal because of pharmacokinetic constraints and lack of target specificity. Newer approaches including isoform-specific NKCC1 inhibitors with increased central nervous system penetration, and direct and indirect strategies to enhance KCC2-mediated neuronal chloride extrusion, might allow therapeutic modulation of the GABAergic system for neonatal seizure treatment.

Dravet syndrome--from epileptic encephalopathy to channelopathy.

Abstract: Mutations in the gene encoding the α1 subunit of the voltage gated sodium channel (SCN1A) are associated with several epilepsy syndromes, ranging from relatively mild phenotypes found in families with genetic epilepsy with febrile seizures plus (GEFS+) to the severe infant-onset epilepsy Dravet syndrome. Evidence has emerged of the consequences of SCN1α dysfunction in different neuronal networks across the brain pointing toward a channelopathy model causing the neurologic features of Dravet syndrome that is beyond purely seizure related damage. A genetic change will present according to its severity, the genetic background of the individual, and environmental factors, and will affect a variety of neuronal networks according to channel distribution. This already-vulnerable system may be susceptible to secondary aggravating events such as status epilepticus. The channelopathy model implies that pharmacologic treatment and the restoration of impaired γ-aminobutyric acid (GABA)ergic neurotransmission might not only help prevent seizures but might affect the comorbidities of the syndrome. This critical review explores recent evidence relating to the pathogenicity of SCN1A mutations in Dravet syndrome and the effect these have on the wider disease phenotype and discusses whether knowledge of specific genotypes can influence clinical practice. Genetic technology is currently advancing at unprecedented speed and will increase our knowledge of new genes and interacting genetic networks. Clinicians and geneticists will have to work in close collaboration to guarantee good delivery and counseling of genetic testing results.

Medicinal compounds with antiepileptic/anticonvulsant activities.

Abstract: Summary Objective Epilepsy is a serious neural disease that affects around 50 million people all over the world. Although for the majority patients with epilepsy, seizures are well controlled by currently available antiepileptic drugs (AEDs), there are still >30% of patients suffered from medically refractory epilepsy and approximately 30–40% of all epileptic patients affected by numerous side effects and seizure resistance to the current AEDs. Therefore, many researchers try to develop novel approaches to treat epilepsy, for example, to discover new antiepileptic constituents from herbal medicines. Although there are already several reviews on phytotherapy in epilepsy, most of them placed emphasis on the plant crude extracts or their isolated fractions, not pure active compounds derived from herbal medicines. This article aims to review components in herbal medicines that have shown antiepileptic or anticonvulsant properties. Methods We searched online databases and identified articles using the preset searching syntax and inclusion criteria. The active medicinal compounds that have shown anticonvulsant or antiepileptic activity were included and classified according to structural types. Results We have reviewed herein the active constituents including alkaloids, flavonoids, terpenoids, saponins, and coumarins. The screening models, the seizures-inducing factors and response, the effective dose, the potential mechanisms, as well as the structure-activity relationships in some of these active components have also been discussed. Significance The in vitro and in vivo experimental data reviewed in this paper would supply the basic science evidence for research and development of novel AEDs from medicinal plants.

A validation of the new definition of drug-resistant epilepsy by the International League Against Epilepsy.

Abstract: Summary Objective To establish applicability, the recently proposed International League Against Epilepsy (ILAE) consensus on drug-resistant epilepsy (DRE) requires testing in clinical and research settings. This study evaluates the reliability and validity of these criteria in a clinical population. Methods In phase I, two independent evaluators reviewed 97 randomly selected medical records of patients with epilepsy at two separate intervals. Both ILEA consensus and standard diagnostic criteria were employed. Kappa, weighted kappa, and intraclass correlation coefficient (ICC) were used to determine interobserver and intraobserver variability. In phase II, ILAE consensus criteria were applied to 250 patients with epilepsy to determine risk factors associated with development of DRE and to calculate point prevalence. Results The interobserver agreement of the four definitions was as follows: Berg (0.56), Kwan and Brodie (0.58), Camfield and Camfield (0.69), and ILAE (0.77). The intraobserver agreement of the four definition was as follows: Berg (0.81), Kwan and Brodie (0.82), Camfield and Camfield (0.72), and ILAE (0.82). The prevalence of DRE was the following: with the Berg's definition was 28.4%, Kwan and Brodie 34%, Camfield and Camfield 37%, and with ILAE was 33%. Significance This is first study to establish reliability and validity of ILAE criteria for the diagnosis of DRE. This new definition compares favorably with previously established constructs, which continue to retain clinical significance.

Continuous EEG monitoring: a survey of neurophysiologists and neurointensivists.

Abstract: Summary Objective Continuous EEG monitoring (cEEG) of critically ill adults is being used with increasing frequency, and practice guidelines on indications for cEEG monitoring have recently been published. However, data describing the current practice of cEEG in critically ill adults is limited. We aimed to describe the current practice of cEEG monitoring in adults in the United States. Methods A survey assessing cEEG indications and procedures was sent to one intensivist and one neurophysiologist responsible for intensive care unit (ICU) cEEG at 151 institutions in the United States. At some institutions only one physician could be identified. Results One hundred thirty-seven physicians from 97 institutions completed the survey. Continuous EEG is utilized by nearly all respondents to detect nonconvulsive seizures (NCS) in patients with altered mental status following clinical seizures, intra cerebral hemorrhage (ICH), traumatic brain injury, and cardiac arrest, as well as to characterize abnormal movements suspected to be seizures. The majority of physicians monitor comatose patients for 24–48 h. In an ideal situation with unlimited resources, 18% of respondents would increase cEEG duration. Eighty-six percent of institutions have an on-call EEG technologist available 24/7 for new patient hookups, but only 26% have technologists available 24/7 in-house. There is substantial variability in who reviews EEG and how frequently it is reviewed as well as use of quantitative EEG. Significance Although there is general agreement regarding the indications for ICU cEEG, there is substantial interinstitutional variability in how the procedure is performed.

The variable phenotypes of KCNQ-related epilepsy.

Abstract: Summary Mutations in KCNQ2 and KCNQ3 were originally described in infants with benign familial neonatal seizures (BFNS). Recently, KCNQ2 mutations have also been shown to cause epileptic encephalopathy. This report describes three infants carrying abnormalities of KCNQ2 and one infant with a KCNQ3 mutation. The different KCNQ2 abnormalities led to different phenotypes and included a novel intragenic duplication, c.419_430dup, in an infant with BFNS, a 0.761Mb 20q13.3 contiguous gene deletion in an infant with seizures at 3 months, and a recurrent de novo missense mutation c.881C>T in a neonate with “KCNQ2-encephalopathy.” The mutation in KCNQ3, c.989G>A, was novel and occurred in an infant with BFNS. KCNQ-related seizures often present with tonic/clonic manifestations, cyanosis, or apnea. Certain genotype–phenotype correlations help predict outcome. Similarly affected family members suggests benign familial “KCNQ-related” epilepsy, whereas neonatal seizures with unexplained multifocal epileptiform discharges or burst suppression on electroencephalography, and acute abnormalities of the basal ganglia/thalami are suggestive of KCNQ2-encephalopathy, which is often sporadic. 20q13.33 contiguous gene deletion encompassing KCNQ2 may harbor atypical features depending on deletion size. Although the phenotype often guides direct targeted gene testing in these conditions, array CGH should also be considered in suspected sporadic or atypical familial cases to diagnose 20q13.33 deletion.

The spatial and signal characteristics of physiologic high frequency oscillations.

Abstract: Summary Objectives To study the incidence, spatial distribution, and signal characteristics of high frequency oscillations (HFOs) outside the epileptic network. Methods We included patients who underwent invasive evaluations at Yale Comprehensive Epilepsy Center from 2012 to 2013, had all major lobes sampled, and had localizable seizure onsets. Segments of non–rapid eye movement (NREM) sleep prior to the first seizure were analyzed. We implemented a semiautomated process to analyze oscillations with peak frequencies >80 Hz (ripples 80–250 Hz; fast ripples 250–500 Hz). A contact location was considered epileptic if it exhibited epileptiform discharges during the intracranial evaluation or was involved ictally within 5 s of seizure onset; otherwise it was considered nonepileptic. Results We analyzed recordings from 1,209 electrode contacts in seven patients. The nonepileptic contacts constituted 79.1% of the total number of contacts. Ripples constituted 99% of total detections. Eighty-two percent of all HFOs were seen in 45.2% of the nonepileptic contacts (82.1%, 47%, 34.6%, and 34% of the occipital, parietal, frontal, and temporal nonepileptic contacts, respectively). The following sublobes exhibited physiologic HFOs in all patients: Perirolandic, basal temporal, and occipital subregions. The ripples from nonepileptic sites had longer duration, higher amplitude, and lower peak frequency than ripples from epileptic sites. A high HFO rate (>1/min) was seen in 110 nonepileptic contacts, of which 68.2% were occipital. Fast ripples were less common, seen in nonepileptic parietooccipital regions only in two patients and in the epileptic mesial temporal structures. Conclusions There is consistent occurrence of physiologic HFOs over vast areas of the neocortex outside the epileptic network. HFOs from nonepileptic regions were seen in the occipital lobes and in the perirolandic region in all patients. Although duration of ripples and peak frequency of HFOs are the most effective measures in distinguishing pathologic from physiologic events, there was significant overlap between the two groups.

Adverse effects and safety profile of perampanel: a review of pooled data.

Abstract: Quality of life is directly related to the number and severity of adverse effects, and a successful antiepileptic medication must demonstrate a good balance between efficacy and tolerability. Perampanel is a newly licensed antiepileptic medication for the adjunctive treatment of patients (age 12 and older) with partial epilepsy with or without secondary generalization. Safety endpoints in the three phase III trials (304, 305, and 306) included treatment-emergent adverse events (TEAEs), vital signs, clinical laboratory parameters, and electrocardiography studies (ECGs). The most common adverse drug reactions in patients receiving perampanel were dizziness, somnolence, fatigue, irritability, nausea, and falls. Of particular concern to patients are cognitive and psychiatric side effects. Overall, depression and aggression were reported more frequently in patients taking perampanel, particularly at higher doses, than in patients taking placebo. TEAEs necessitated the withdrawal of perampanel in 99 patients (9.5%) and placebo in 21 patients (4.8%). Typically this was due to dizziness, convulsion, and somnolence. There were no clinically important changes or treatment group differences in vital signs, ECG measures, or biochemical or hematologic parameters. Weight increase of greater than 7% was seen in 14.6% of perampanel-treated patients versus 7.1% of placebo-treated patients. Overall, perampanel appears to be associated with a relatively low incidence of serious adverse effects, particularly at low doses, and the majority of TEAEs were mild or moderate in intensity. The incidence of predictable side effects, such as somnolence and dizziness, is seen more frequently at higher doses. Of importance is the greater rate of psychiatric side effects in patients treated with perampanel, principally, irritability and aggression, than with placebo. However, the rate of serious psychiatric TEAEs was low.