Generalized Seizure Types Research Articles

A spike is a spike: On the universality of spike features in four epilepsy models.

Frequency properties of the EEG characteristics of different seizure types including absence seizures have been described for various rodent models of epilepsy. However, little attention has been paid to the frequency properties of individual spike-wave complexes (SWCs), the constituting elements characterizing the different generalized seizure types. Knowledge of their properties is not only important for understanding the mechanisms underlying seizure generation but also for the identification of epileptiform activity in various seizure types. Here, we compared the frequency properties of SWCs in different epilepsy models. A software package was designed and used for the extraction and frequency analysis of SWCs from long-term EEG of four spontaneously seizing, chronic epilepsy models: a post-status epilepticus model of temporal lobe epilepsy, a lateral fluid percussion injury model of post-traumatic epilepsy, and two genetic models of absence epilepsy-GAERS and rats of the WAG/Rij strain. The SWCs within the generalized seizures were separated into fast (three-phasic spike) and slow (mostly containing the wave) components. Eight animals from each model were used (32 recordings, 104 510 SWCs in total). A limitation of our study is that the recordings were hardware-filtered (high-pass), which could affect the frequency composition of the EEG. We found that the three-phasic spike component was similar in all animal models both in time and frequency domains, their amplitude spectra showed a single expressed peak at 18-20 Hz. The slow component showed a much larger variability across the rat models. Despite differences in the morphology of the epileptiform activity in different models, the frequency composition of the spike component of single SWCs is identical and does not depend on the particular epilepsy model. This fact may be used for the development of universal algorithms for seizure detection applicable to different rat models of epilepsy. There is a large variety between people with epilepsy regarding the clinical manifestations and the electroencephalographic (EEG) phenomena accompanying the epileptic seizures. Here, we show that one of the EEG signs of epilepsy, an epileptic spike, is universal, since it has the same shape and frequency characteristics in different animal models of generalized epilepsies, despite differences in recording sites and location.

Effectiveness of add-on acetazolamide in children with drug-resistant CHD2-related epilepsy and in a zebrafish CHD2 model.

CHD2-related epilepsy is characterized by early-onset photosensitive myoclonic epilepsy with developmental delay and a high rate of pharmacoresistance. We sought to evaluate the efficacy of acetazolamide (ACZ) in CHD2-related epilepsy, due to ACZ's unexpected efficacy in our first patient harboring a pathogenic CHD2 variant. We collected patients from different Eastern European countries with drug-resistant CHD2-related epilepsy who were then treated with ACZ. Patients underwent video EEG before and during ACZ treatment. In a zebrafish model of CHD2-related epilepsy, ictal-like events were recorded 5 days post-fertilization after overnight ACZ exposure. Developmental delay preceded the onset of seizures in 10 of the 12 patients. Four had ataxia, and 6 exhibited autistic features. Seizures, primarily myoclonic, began at an average age of 3.4 years and were photosensitive in all 12 patients. Add-on ACZ treatment controlled photosensitive seizures in all patients: 6 became seizure-free, and in the remaining 6, seizure frequency decreased by over 75%. Four patients transitioned to ACZ monotherapy. The median follow-up was 13 months. In the zebrafish model, ACZ exposure reduced ictal-like events by 72%. ACZ, a well-tolerated and cost-effective medication, could be a good option for CHD2-related epilepsy, predominantly manifesting with myoclonic seizures and photosensitivity. PLAIN LANGUAGE SUMMARY: Epilepsy associated with CHD2 mutations is often pharmacoresistant and associated with developmental delay and eventually ataxia. There are several generalized seizure types, including generalized tonic-clonic seizures, but the most characteristic are jerks triggered by light stimulation. We collected 12 patients who received acetazolamide, a drug usually given as a diuretic and registered as a mild antiseizure medication. All jerks triggered by light disappeared while the frequency of spontaneous seizures decreased by over 75%. Further studies are needed to confirm this promising finding and identify the mechanism by which an old compound seems to have such a specific antiseizure effect.

A generalized seizure type: Myoclonic-to-tonic seizure

Background and purposeTo test the hypothesis that myoclonic seizures can evolve to tonic seizures, we documented the electroclinical features of this under-recognized seizure type. MethodsWe observed a distinct seizure pattern starting with myoclonus without returning to an interictal state, which subsequently evolved into generalized tonic seizures. The detailed symptomatic and electroencephalographic characteristics of this seizure were extracted, and the clinical manifestations, drug curative responses in patients with this seizure were reviewed and analyzed. ResultsThe onset of all seizures was characterized by a preceding period of myoclonus and bursts of generalized spike or poly-spike slow wave discharges with high amplitude. This was closely followed by the occurrence of tonic seizures, which were distinguished by bursts of generalized fast activity at 10 Hz or higher frequency. This under-recognized seizure type has been designated as myoclonic-to-tonic (MT) seizure. The number of patients identified with MT seizures in this study was 34. The prevalence rate of MT seizures was found to be higher in males. While MT seizures typically included a tonic component, it should be noted that some patients experiencing this seizure type never presented with isolated tonic seizures. Generalized Epilepsy not further defined (GE) accounted for approximately one-third of the diagnosed cases, followed by Lennox-Gastaut syndrome and Epilepsy with Myoclonic-Atonic seizures. In comparison to other types of epilepsy, GE with MT seizures demonstrated a more favorable prognosis. ConclusionsThe classification of myoclonic-to-tonic seizure represents a novel approach in comprehending the ictogenesis of generalized seizures and can provide valuable assistance to clinicians in epilepsy diagnosis.

Molecular and Phenotypic Characterization of the RORB-Related Disorder.

Heterozygous variants in RAR-related orphan receptor B (RORB) have recently been associated with susceptibility to idiopathic generalized epilepsy. However, few reports have been published so far describing pathogenic variants of this gene in patients with epilepsy and intellectual disability (ID). In this study, we aimed to delineate the epilepsy phenotype associated with RORB pathogenic variants and to provide arguments in favor of the pathogenicity of variants. Through an international collaboration, we analyzed seizure characteristics, EEG data, and genotypes of a cohort of patients with heterozygous variants in RORB. To gain insight into disease mechanisms, we performed ex vivo cortical electroporation in mouse embryos of 5 selected variants, 2 truncating and 3 missense, and evaluated on expression and quantified changes in axonal morphology. We identified 35 patients (17 male, median age 10 years, range 2.5-23 years) carrying 32 different heterozygous variants in RORB, including 28 single-nucleotide variants or small insertions/deletions (12 missense, 12 frameshift or nonsense, 2 splice-site variants, and 2 in-frame deletions), and 4 microdeletions; de novo in 18 patients and inherited in 10. Seizures were reported in 31/35 (89%) patients, with a median age at onset of 3 years (range 4 months-12 years). Absence seizures occurred in 25 patients with epilepsy (81%). Nineteen patients experienced a single seizure type: absences, myoclonic absences, or absences with eyelid myoclonia and focal seizures. Nine patients had absence seizures combined with other generalized seizure types. One patient had presented with absences associated with photosensitive occipital seizures. Three other patients had generalized tonic-clonic seizures without absences. ID of variable degree was observed in 85% of the patients. Expression studies in cultured neurons showed shorter axons for the 5 tested variants, both truncating and missense variants, supporting an impaired protein function. In most patients, the phenotype of the RORB-related disorder associates absence seizures with mild-to-moderate ID. In silico and in vitro evaluation of the variants in our cohort, including axonal morphogenetic experiments in cultured neurons, supports their pathogenicity, showing a hypomorphic effect.

Anti-seizure medication prescription preferences: a Moroccan multicenter study.

The management of epilepsy is mainly based on antiseizure medications (ASMs). More than 20 ASMs have been introduced in clinical practice, providing a multitude of prescription choices. To date, there are no published data on the trends in ASMs prescriptions in Morocco. Therefore, we conducted a survey among practicing neurologists in seven tertiary referral hospitals in Morocco to study the current ASMs prescription preferences and their modifying factors. Our descriptive and analytical cross-sectional study was based on a survey sent between January and April 2022 to neurologists practicing in seven tertiary referral hospitals in Morocco. Information regarding the prescription of ASMs was collected using an exploitation form and analyzed using the SPSS version 13 software. Based on questionnaire responses, our results showed that Valproic acid (96.3%) and Lamotrigine (59.8%) were the two most prescribed ASMs for generalized seizure types. For focal seizure types, Carbamazepine (98.8%) and Levetiracetam (34.1%) were the most commonly prescribed drugs, whereas for combined focal and generalized seizure types, the combination of Valproic acid and Carbamazepine (38.55%) was the most prescribed. Phenobarbital was the most commonly prescribed ASM for status epilepticus (40.2%). These prescription preferences were mainly due to seizure types, cost, health insurance coverage, years of experience, and additional epileptology training (p < 0.05). Our results show a shift in the prescription of ASMs in Morocco. Similar to many other countries, valproic acid and carbamazepine are considered the first-line treatments for generalized and focal seizure types. Some factors remain as major challenges in enhancing epilepsy management in Morocco.

Epilepsy and EEG features in Angelman syndrome

Аngelman syndrome (AS) is an orphan disease caused by loss of function of the maternal allele of the UBE3A gene on chromosome 15 (region 15q11.2-q13), characterized by severe mental and speech retardation, movement disorders, unique behavior in the form of frequent laughter, and epileptic seizures with characteristic anomalies in EEG. Epilepsy is often drug-resistant, generalized seizure types dominate, among which myoclonic seizures and atypical absences are the most common. Infantile spasms are rare in AS children, but the EEG pattern, especially in infancy, in the form of diffuse slow-wave activity with multiregional and generalized epileptiform activity, may resemble a hypsarrhythmia pattern. We present own observation of a child in whom the EEG was incorrectly described as a hypsarrhythmia pattern, and hormonal therapy was prescribed with suspicion of epileptic spasms. In this article, we made a brief review of the literature on the treatment of epilepsy in AS patients with a recommended algorithm for choosing an antiepileptic drug (AED). In young children with developmental delay, a routine EEG pattern similar to hypsarrhythmia, but with out of clinical and EEG patterns of spasms, it is necessary to conduct video-EEG monitoring with recording of sleep, to exclude the “pseudo-hypsarrhythmia” pattern, which is especially important when Angelman syndrome is suspected. In the treatment of epilepsy in Angelman syndrome, it is necessary to adhere to the recommended, according to the literature, algorithm for choosing AEDs

Generalized onset seizures with focal evolution (GOFE) – a largely unknown ictal variation in genetic generalized epilepsies

PurposeAt onset of generalized seizures, focal electroclinical features are commonly seen, while generalized onset seizures with focal evolution (GOFE) are largely unknown bearing the risk of misclassification. MethodsIn two German epilepsy-centers, patients with GOFE documented by video-EEG monitoring (VEM) between 2017 and 2022 were identified retrospectively. In addition to analysis of ictal electroclinical features, detailed epilepsy and family history, response to antiseizure medication (ASM), and findings from neuroimaging were considered. ResultsWe identified five patients with GOFE, three females, age 14 to 22 years. All patients developed genetic generalized epilepsy in childhood or adolescence, each presenting with two or three generalized seizure types. In each of the five patients, one GOFE was recorded by VEM. At onset, EEG seizure patterns were characterized by generalized spike-wave discharges at 2.5 to 3.5/sec for 9 to 16 sec followed by focal evolution of the discharges. Interictally, all patients presented with generalized spike-wave discharges without focal abnormalities. Semiology at onset was behavioral arrest in two patients and generalized increase in tone in one, while two onsets were clinically inapparent. Semiological signs during focal evolution were variable, comprising head and body version, figure 4 sign, unilateral arm clonic activity, and staring with oral automatisms. In one case, focality involved both hemispheres successively. ConclusionProminent focal semiological features in GOFE carry a high risk of misclassification as focal seizures and epilepsy and thus wrong choice of ASM. This calls for low-threshold VEM if any doubts of focal genesis of seizures exist.

Comment: Amenable Treatable Severe Pediatric Epilepsies

Phillip L. Pearl Seminars in Pediatric Neurology Volume 23, Issue 2, May 2016, Pages 158-166 Vitamin-dependent epilepsies and multiple metabolic epilepsies are amenable to treatment that markedly improves the disease course. Knowledge of these amenably treatable severe pediatric epilepsies allows for early identification, testing, and treatment. These disorders present with various phenotypes, including early onset epileptic encephalopathy (refractory neonatal seizures, early myoclonic encephalopathy, and early infantile epileptic encephalop athy), infantile spasms, or mixed generalized seizure types in infancy, childhood, or even adolescence and adulthood. The disorders are presented as vitamin responsive epilepsies such as pyridoxine, pyridoxal-5-phosphate, folinic acid, and biotin; transportopathies like GLUT-1, cerebral folate deficiency, and biotin thiamine responsive disorder; amino and organic acidopathies including serine synthesis defects, creatine synthesis disorders, molybdenum cofactor deficiency, and cobalamin deficiencies; mitochondrial disorders; urea cycle disorders; neurotransmitter defects; and disorders of glucose homeostasis. In each case, targeted intervention directed toward the underlying metabolic pathophysiology affords for the opportunity to significantly effect the outcome and prognosis of an otherwise severe pediatric epilepsy.

Effectivity of Pyridoxine as Adjuvant Therapy of Phenytoin in Patients with Epilepsy at Soebandi Regional Hospital Jember

Phenytoin is an antiepileptic drug used as monotherapy for partial and generalized tonic-clonic seizures for more than 50 years. Pyridoxine is a water-soluble vitamin widely used for seizure patients unresponsive to standard treatment regimens. This study was conducted to determine the effect of pyridoxine as adjuvant therapy in epilepsy patients receiving phenytoin and to determine the relationship between age, gender, type of epilepsy, and duration of therapy on the incidence of seizures in epilepsy patients at Soebandi Regional Hospital Jember. This research is an observational analytic study with a cross sectional design. The data was taken from the patient's medical record at Soebandi Hospital Jember. The number of samples in each treatment group was 18 samples so the total number of samples in this study was 36 samples. Samples were taken using total sampling technique. Data analysis was performed using Chi-Square test on bivariate analysis and The Logistic test on multivariate analysis. The sample in this study was dominated by male patients (52.8%), aged 19-59 years (52.8%), had epilepsy with generalized seizure type (86.1%), and received therapy for &lt; 3 years (77.8%). The results of bivariate and multivariate analysis showed correlation between the administration of pyridoxine and the incidence of seizures, indicating that phenytoin therapy with pyridoxine adjuvants was more effective than monotherapy phenytoin. Other factors such as gender, age, type of epilepsy, and duration of therapy were not proven to have a correlation with the incidence of seizures in epilepsy patients at Soebandi Hospital Jember.

Determination of Parental Concerns about Seizures among Children with Epilepsy

Epilepsy is often misunderstood and not taken seriously as compared to other diseases the reason behind it is a lack of health-related knowledge, poor economic condition, and shortness of health facilities in remote areas. Objective: To determine the parental concerns about seizures among children with epilepsy. Methods: A cross-sectional study was carried out in the Neurology division of a public hospital. After receiving informed consent, the current study involved 36 parents of epileptic patients. The parents of children with epilepsy who visited the neurology clinic (OPD) were included. The parent's concerns about seizures scale was used to measure parental worry about seizures in children with epilepsy. Results: 36 parents of epileptic patients were enrolled in the current study. There were 33.3% male and 66.7% female participants. The majority of the participants dealt with children having generalized seizure types. Parents were more concerned about seizures can lead to underlying disease 23(63.9), they are often concerned that their child’s epilepsy has unknown cause 14(38.9), brain damage 13(36.1), loss of intelligence 17(47.2), and child developing emotional problems 13(36.1). They also show concern sometimes when a seizure may be triggered due to if they do or don’t do something 22(61.1) and they also think that their child may have learning issues 11(30.6). Conclusions: The current study shows that parents play a vital role in improving the family functioning of epileptic families. Parents played an important role in helping children with epilepsy cope with their differences from other children.

ILAE definition of the Idiopathic Generalized Epilepsy Syndromes: Position statement by the ILAE Task Force on Nosology and Definitions.

In 2017, the International League Against Epilepsy (ILAE) Classification of Epilepsies described the "genetic generalized epilepsies" (GGEs), which contained the "idiopathic generalized epilepsies" (IGEs). The goal of this paper is to delineate the four syndromes comprising the IGEs, namely childhood absence epilepsy, juvenile absence epilepsy, juvenile myoclonic epilepsy, and epilepsy with generalized tonic-clonic seizures alone. We provide updated diagnostic criteria for these IGE syndromes determined by the expert consensus opinion of the ILAE's Task Force on Nosology and Definitions (2017-2021) and international external experts outside our Task Force. We incorporate current knowledge from recent advances in genetic, imaging, and electroencephalographic studies, together with current terminology and classification of seizures and epilepsies. Patients that do not fulfill criteria for one of these syndromes, but that have one, or a combination, of the following generalized seizure types: absence, myoclonic, tonic-clonic and myoclonic-tonic-clonic seizures, with 2.5-5.5 Hz generalized spike-wave should be classified as having GGE. Recognizing these four IGE syndromes as a special grouping among the GGEs is helpful, as they carry prognostic and therapeutic implications.

Antiepileptic drug monotherapy for epilepsy: a network meta-analysis of individual participant data.

Antiepileptic drug monotherapy for epilepsy: a network meta-analysis of individual participant data.

Generalized absence seizures: Where do we stand today?

AbstractGeneralized absence seizures are discussed here with respect to changing scientific concepts and newer findings, challenging the strict dichotomy of “generalized” vs. “focal” which may be counterproductive to the development of new ideas and treatments. Data from semiology, structural, and functional studies using quantitative electroencephalography (EEG), video-EEG monitoring, magnetoencephalography, magnetic resonance imaging, and positron emission tomography as well as neuropathology suggest a nosological spectrum from focal to generalized seizure-generating mechanisms. The terms “focal” and “generalized” as used to describe seizures represent abstractions and idealizations rather than ontological entities. The new terminology and classification of the ILAE (2017), despite its enormous merits, unfortunately also facilitates and fosters reductionist thinking, which may be pragmatic from a utilitarian perspective, but risks hindering scientific developments for the future. For instance, the seizure semiology of absences as a paradigmatic generalized seizure type is now classified as “non-motor seizure.” A detailed phenomenological analysis reveals that motor activity is an integral part of this seizure type. Many motor and so-called automatic absence symptoms can be understood as correlated elements of a general organization plan of the cortex. Corresponding functional and structural changes seen in imaging and high-resolution electrophysiology studies indicate focal contributions to seizure generation and a combination of focal and generalized features. Functional findings indicate that the frontal lobe with its projections to other brain areas may play an important role in generalized absence seizures. In this critical review we assess the evolution of pathophysiological concepts through the ages and present new research approaches for diagnosis and treatment.

Evaluation of Family functioning among parents of epileptic patients

Epilepsy has aggregate of risk characteristic’s as, age of onset, triggering factors, genetics, natural history, prognosis, and it is not a condition based on single aspect or cause. Due to social problems, family functioning of epileptic patients suffers badly. The basic purpose of the study is to investigate the role of family functioning of the parents who has epileptic patients. Methods: Across-sectional study was conducted at Muzaffargarh Hospital Neurology OPD department. Total 36 parents were enrolled. All parents of children, who have 8 to18 years of age, which are diagnosis of epilepsy, were included in current study Data was collected on a predesign questionnaire and for family functioning the Family Assessment Device (FAD) was used. Statistical analysis was performed by using the Statistical Package for Social Sciences (spss) version 26. The frequencies, proportions were calculated for Qualitative variables and Mean + SD were calculated for quantitative variables. Results: The mean age of parents was 38.58+7.55 and children were 12.31+3.34. Out of 36 participants 12(33.3%) were males whereas 24(66.7%) were females. Majority of parents were holding secondary degree 13(36.1%), were unemployed 24(66.7%), 21(58.3%) were from rural area and dealing with generalized seizure type children 24(66.7%). The average seizures frequency per month was 2.64+1.15. The families of epileptic patients were more dysfunctional, especially in terms of problem solving (2.66+0.43), behavior control (2.68+0.49), affective involvement (2.62+0.64) and also family’s faces difficulties in finding their role (2.48+0.56). Conclusion: The families of epileptic patients have more dysfunctional, especially in terms of problem solving, behavior control, affective involvement and also families faces difficulties in finding their role. Therefore educational programme focusing on the importance of family functioning should be provided so that the aspect of treatments and social life of patients get improved. Keywords: Epilepsy, Family functioning, Social Support, Family support

Cortical responsive neurostimulation in a baboon with genetic generalized epilepsy

ObjectiveTo evaluate the efficacy of cortical responsive neurostimulation (CRN) in a male baboon with epilepsy and with genetic generalized epilepsy (GGE), as well as the alteration of seizure patterns and their circadian rhythms due to treatment. MethodsThe baboon was implanted with two subdural frontoparietal strips, bridging the medial central sulci bilaterally. Electrocorticography (ECoG) data were downloaded daily during a three-month baseline, then every 2–3 days over a five-month treatment period. Long episodes, reflecting ictal or interictal epileptic discharges, were also quantified. ResultsTwenty-three generalized tonic-clonic seizures (GTCS) and 2 episodes of nonconvulsive status epilepticus (NCSE) were recorded at baseline (median 8 events/month), whereas 26 GTCS were recorded under treatment (median 5/month). Similarly, daily indices of long episodes decreased from 0.46 at baseline to 0.29 with treatment. Ictal ECoG patterns and the circadian distribution of GTCS were also altered by RNS therapy. SignificanceThis case study provides the proof-of-concept for RNS therapy in the baboon model of GGE. Cortical responsive neurostimulation (CRN) demonstrated a 38% median reduction in GTCS. Distinct ictal patterns were identified, which changed over the treatment period; the circadian pattern of his GTCS also shifted gradually from night to daytime with treatment. Future studies targeting the thalamic nuclei, or combining cortical and subcortical sites, may further improve detection and control of GTCS as well as other generalized seizure types. More broadly, this study demonstrates opportunities for evaluating seizure detection as well as chronic therapeutic interventions over long term in the baboon.

Absence-to-bilateral-tonic-clonic seizure: A generalized seizure type.

ObjectiveTo test the hypothesis that absence seizures can evolve to generalized tonic-clonic seizures, we documented electroclinical features of this novel seizure type.MethodsIn 4 large video-EEG databases, we identified recordings of seizures starting with impaired awareness that, without returning to baseline interictal state, evolved to generalized tonic-clonic seizures. We extracted the detailed semiologic and electrographic characteristics of these seizures, and we documented the clinical background, diagnoses, and therapeutic responses in these patients.ResultsWe identified 12 seizures from 12 patients. All seizures started with a period of impaired awareness and bursts of generalized spike or polyspike and slow-wave discharges, the hallmark of absence seizures. Without returning to baseline, the nonmotor (absence) phase was followed by tonic-clonic convulsions. We called this novel generalized seizure type absence-to-bilateral-tonic-clonic seizure. Most patients had idiopathic generalized epilepsies, although with a high incidence of unusual features and poor therapeutic response.ConclusionsAbsence-to-bilateral-tonic-clonic seizures are a novel generalized seizure type. Clinicians should be aware of this seizure for correctly diagnosing patients. This novel seizure type may further elucidate generalized ictogenesis.

Karakteristik Penderita Epilepsi di Bangsal Anak RSUP Dr. M. Djamil Padang Tahun 2018

Background: Epilepsy is a condition characterized by recurrent seizures that occur due to the disruption of brain function caused by an abnormal electrical charge on brain neurons. Epilepsy has two categories of seizures, they are focal seizures and generalized seizures. The incidence of epilepsy is estimated to be more prevalent in developing countries than developed countries. In 2017, the number of cases of children with epilepsy in West Sumatra, especially at RSUP Dr. M. Djamil Padang, there are 1081 cases in the outpatient and inpatient cases and will be expected to increase every year.Purpose: To find out the characteristics of epilepsy disease in the children's ward RSUP Dr. M. Djamil Padang in 2018.Method: This research was conducted at RSUP Dr. M. Djamil Padang. This research is descriptive with cross sectional design. Data sources from secondary data derived from medical records. Samples were selected using inclusion and exclusion criteria. Data analysis uses univariate analysis.Results: The results of the study were obtained from 65 samples suffering from epilepsy, there are age 0-5 years as many as 37 people (56.9%), male gender as many as 39 people (60%), do not have a family history of epilepsy as much as 62 people (95.4%), picture of sharp wave and spikes EEG as many as 30 people (46.2%), generalized seizure type as many as 57 people (87.7%) and valproic acid as one of the management of epilepsy as many as 32 people (49, 2%).Conclusion: From the results of this study, it can be concluded that most people with epilepsy are aged 0-5 years with male sex and do not have a family history of epilepsy. The types of EEG images are sharp waves and spikes, the type of generalized seizures with the most management of valproic acid.

Accuracy of ICD-10-CM claims-based definitions for epilepsy and seizure type

ObjectiveTo evaluate the accuracy of ICD-10-CM claims-based definitions for epilepsy and classifying seizure types in the outpatient setting. MethodsWe reviewed electronic health records (EHR) for a cohort of adults aged 18+ years seen by six neurologists who had an outpatient visit at a level 4 epilepsy center between 01/2019−09/2019. The neurologists used a standardized documentation template to capture the diagnosis of epilepsy (yes/no/unsure), seizure type (focal/generalized/unknown), and seizure frequency in the EHR. Using linked ICD-10-CM codes assigned by the provider, we assessed the accuracy of claims-based definitions for epilepsy, focal seizure type, and generalized seizure type against the reference-standard EHR documentation by estimating sensitivity (Sn), specificity (Sp), positive predictive value (PPV), and negative predictive value (NPV). ResultsThere were 673 eligible outpatient encounters. After review of EHRs for standardized documentation, an analytic sample consisted of 520 encounters representing 402 unique patients. In the EHR documentation, 93.5 % (n = 486/520) of encounters were with patients with a diagnosis of epilepsy. Of those, 66.0 % (n = 321/486) had ≥1 focal seizure, 41.6 % (n = 202/486) had ≥1 generalized seizure, and 7% (n = 34/486) had ≥1 unknown seizure. An ICD-10-CM definition for epilepsy (i.e., ICD-10 G40.X) achieved Sn = 84.4 % (95 % CI 80.8−87.5%), Sp = 79.4 % (95 % CI 62.1−91.3%), PPV = 98.3 % (95 % CI 96.6−99.3%), and NPV = 26.2 % (95 % CI 18.0−35.8%). The classification of focal vs generalized/unknown seizures achieved Sn = 69.8 % (95 % CI 64.4−74.8%), Sp = 79.4 % (95 % CI 72.4−85.3%), PPV = 86.8 % (95 % CI 82.1−90.7%), and NPV = 57.5 % (95 % CI 50.8−64.0%). ConclusionsClaims-based definitions using groups of ICD-10-CM codes assigned by neurologists in routine outpatient clinic visits at a level 4 epilepsy center performed well in discriminating between patients with and without a diagnosis of epilepsy and between seizure types.

Phenobarbitone versus phenytoin monotherapy for epilepsy: an individual participant data review.

Phenobarbitone versus phenytoin monotherapy for epilepsy: an individual participant data review.

Carbamazepine versus phenytoin monotherapy for epilepsy: an individual participant data review.

Carbamazepine versus phenytoin monotherapy for epilepsy: an individual participant data review.